General Principles of the available ICC Standard Methods

2. Scope
This Standard specifies general conditions relating to the sampling for assessment of quality of cereal grains. It does not apply to seed grain.

3. Definitions
For the purpose of this Standard, the following definitions apply.

3.1. Consignment
The quantity of grain dispatched or received at one time and covered by a particular contract or shipping document. It may be composed of one or more lots.

3.2. Lot
A stated quantity, presumed to be of uniform characteristics, taken from the consignment, and allowing the quality to be assessed.

3.3. Increment
A small quantity of grain taken from a single position in the lot. A series of increments should be taken from different positions in the lot.

3.4. Bulk sample
The quantity of grain removed from the bulk sample and intended for analysis or other examination.

4. Principle
The principle of the method is to obtain an average sample corresponding in every respect of the average characteristics and composition of the parcel from which it has been drawn.

ICC STANDARD No. 102/1

2. Scope
This method is applicable to the determination of the different components of Besatz in wheat used for the milling of flour and of semolina. It is not applicable to seed wheat or to wheat for feeding purposes.

3. Definition
The term "Besatz" of wheat applies to all components of a wheat sample which differ from the normal basic variety.

3.1. Classification of Besatz

3.1.1. Grain dockage
Broken grains
Shrivelled grains
Other grains or grains of contrasting varieties
Sprouted grains
Insect-damaged grains
Frost-damaged grains
Grains with discoloured germs

3.1.2. Black dockage
Weed seeds (toxic; non-toxic)
Ergot
Unsound grains
Smutty grains
Impurities and chaff

3.1.3. Total Besatz
Total Besatz is the sum of grain dockage and black dockage.

3.1.4. Animal impurities or impurities of animal origin
Insect fragments

3.2. Definition of the different groups of Besatz

3.2.1. Broken grains
The term "broken grains" applies to all grains belonging to the basic variety, which have not been attacked but in which part of the endosperm is exposed. These include bruised grains and grains with the germ knocked out.

3.2.2. Shrivelled grains
The term "shrivelled grains" applies to all grains which, after removal of all other groups of Besatz from the wheat sample, pass through a sieve with 2 mm slot-width. Further, all the green, immature grains are included in this group.

3.2.3. Other grains, grains of contrasting varieties
This term applies to all cereal grains differing from the normal basic variety and to their Besatz components. In a durum wheat sample all vulgare wheat grains and their Besatz components are to be classified as other grains, and vice versa.

3.2.4. Sprouted grains
The term "sprouted grains" applies to all grains in which the radicle or plumule is clearly visible to the naked eye. The general habit of the wheat should, however, be considered in the assessment of the proportion of sprouted grains. In many wheat samples, e.g., in durum, it is a characteristic of the variety that the germ emerges to a considerable extent, so that movement breaks the bran overlaying the germ, giving a false impression of sprouting. Such grains should not be classified as sprouted grains. Sprouted grains are only those in which distinctly visible changes, easily distinguishable from the normal state, have occurred in the germ.

3.2.5. Insect-damaged grains
This term applies to all grains showing signs of insect bites or punctures (wheat blossom midges), as well as all grains attacked by wheat bug.

3.2.6. Frost-damaged grains
No definition of frost-damaged grains is necessary.

3.2.7. Grains with discoloured germ
This term applies to grains with a brown to brown-black colour of the bran (overlying the germ), the germ being intact and showing no signs of sprouting.

3.2.8. Weed seeds
No definition of weed seeds is necessary.

3.2.9. Ergot
No definition of ergot is necessary.

3.2.10. Unsound grains
This term applies to all grains that have become unsuitable for human consumption because of rot, mould, bacterial attack, or other influences, and includes heat-damaged grains. Heat-damaged grains are fully developed grains the bran of which is greybrown to black and the endosperm of which is yellowish grey to brownish black in colour on dissection. Grains attacked by Wheat Blossom Midge (Contarinia tritic Kirby) are to be classified as unsound grains only if secondary mould attack has discoloured more than half of the surface of the grain to a grey to black colour. If the discolouration has affected less than half of the surface of the grain, the grain is to be classified as insect-damaged.

3.2.11. Smutty grains
No definition of smutty grains is necessary.

3.2.12. Impurities and chaff
These terms apply to all components of a wheat sample which will pass through a sieve with 1 mm slot-width. Stones, mud balls and straws, chaff and similar impurities which are found on the sieve also belong to this group.

3.2.13. Insect fragments
No definition of insect fragments is necessary.

3.2.14. Weevils
Weevils are grain weevils, as well as other insects which damage grain.

4. Principle
The principle of this method is to separate all the groups of Besatz, defined under 3.2., from the normal basic grains, either by sieving or by manual selection.

ICC STANDARD No. 103/1

2. Scope
This method is applicable to the determination of the different components of Besatz in rye used for the milling of bread flour. It is not applicable to seed rye or to rye for feeding purposes.

3. Definition
The term "Besatz" applies to all components of a rye sample which differ from the normal basic variety.

3.1. Classification of Besatz

3.1.1. Grain dockage
Broken grains
Shrivelled grains
Other grains
Sprouted grains
Insect-damaged grains
Frost damaged grains

3.1.2. Black dockage
Weed seeds (toxic; non-toxic)
Ergot
Unsound grains
Impurities and chaff

3.1.3. Total Besatz
Total Besatz is the sum of grain dockage and black dockage.

3.1.4. Animal impurities or impurities of animal origin
Insect fragments
Weevils

3.2. Definition of the different groups of Besatz

3.2.1. Broken grains
The term "broken grains" applies to all grains belonging to the basic variety, which have not been attacked, but which part of the endosperm is exposed. These include bruised grains and grains with the germ knocked out.

3.2.2. Shrivelled grains
The term "shrivelled grains" applies to all grains which, after removal of all other groups of Besatz from the rye sample, pass through a sieve with 1.8 mm slot-width in the case of European rye, or through a sieve with 1.7 mm slot-width for rye of other origin.
Further, all the green immature grains are included in this group.

3.2.3. Other grains
The term "sprouted grains" applies to all grains in which the radical or plume is clearly visible to the naked eye. The general habit of the cereal sample should, however, be considered in the assessment of the proportion of sprouted grains. In many rye samples it is a characteristic of the variety that the germ emerges to a considerable extent, so that movement breaks the bran overlying the germ, giving an erroneous impression of sprouting. Such grains should not be classified as sprouted grains. Sprouted grains are only those in which distinctly visible changes, easily distinguishable from the normal state, have occurred in the germ.

3.2.4. Insect-damaged grains
This term covers all grains showing signs of insect attack (including those attacked by wheat blossom midges).

3.2.5. Frost-damaged grains
No definition of frost-damaged grains is necessary.

3.2.6. Weed seeds
No definition of weed seeds is necessary.

3.2.7. Ergot
No definition of ergot is necessary.

3.2.8. Unsound grains
This term covers all grains that have become unsuitable for human consumption because of rot, mould, bacterial attack, or other influences, and includes heat-damaged grains. Heat-damaged grains are fully developed grains the endosperm of which is yellowish brown to brownish black in colour on dissection.

3.2.9. Impurities and chaff
These terms cover all components of a rye sample which will pass through a sieve with 1 mm slot-width. Stones, mud balls, straws, chaff and similar impurities, which are found on the sieve, also belong to the impurities.

3.2.10. Weevils
Weevils are grain weevils, as well as other insects which damage grain.

4. Principle
The principle of this method is to separate all the groups of Besatz defined under 3.2. from the normal basic grains, either by sieving or by manual selection.

ICC STANDARD No. 104/1

2. Scope
This method is applicable to the determination of ash in cereals, and in cereal products for human consumption.

3. Definition
Ash is defined as the quantity of mineral matter which, after application of the described working methods, remains as incombustible residue of the tested substance.

4. Principle
Weigh the test substance, which may have to be preground, into crucibles, and place them into a muffle furnace. The ashing is carried out at 900 °C, and is completed when the cool residue is white or nearly white. As the ash quantity has to be related to dry matter, the moisture content of the test substance has to be determined separately.

ICC STANDARD No. 105/2

2. Scope
This method is envisaged for the determination of crude protein content in cereals and cereal products.

3. Definition
Crude protein is a conventional expression for the total content of nitrogenous compounds of the analysed product, calculated by multiplying the corresponding total nitrogen content by an conventional factor.

4. Principle
The organic matter of the sample is oxidized with concentrated sulfuric acid in the presence of a catalyst: the product of the reaction (NH₄)₂SO₄ is treated by alkali; free ammonia is distilled and titrated.

ICC STANDARD No. 106/2

2. Scope and field of application

2.1.
This International Standard specifies a method for the determination of wet gluten in wheat flour.

2.2.
This method is applicable to different wheat flours (commercial and experimental flours) but not to the coarse whole meal of wheats.

3. Definition
Wet gluten in wheat flour: A plastic-elastic substance, consisting of gliadin and glutenin, obtained by the method specified in this International Standard.

4. Principle
Preparation of dough from a sample of flour and a buffered solution of sodium chloride. Isolation of the wet gluten by washing this dough with a solution of sodium chloride, drying and weighing of the residue.

ICC STANDARD No. 107/1

Determination of the "Falling Number" according to Hagberg - 
as a Measure of the Degree of Alpha-Amylase Activity in Grain and Flour

2. Scope

2.1. The method is applicable to meal and flour of wheat, rye, barley, as well as to other grains and to starch containing and malted products. In this standard the word "flour" also means meals and ground grains (wholemeal).

2.2. By converting the Falling Number into the Liquefaction Number it is possible to calculate the composition of flour mixtures of desired Falling Number.

3. References

ICC-Standard No. 101/1, Sampling of Grains

ICC-Standard No. 130/1, Sampling of Milling Products (semolina, flours, agglomerated flours and by-products

ICC-Standard No. 110/1, Determination of the Moisture, Content of Cereals and Cereal Products (Practical Method)

ICC Recommendation No. 203, Statistical Analysis of the Results of Collaborative Studies

ISO 3696, Water for analytical laboratory use - Specification and test methods

4. Definition
The Falling Number is defined as the time in seconds required to stir and to allow a viscometer stirrer to fall a measured distance through a hot aqueous meal, flour or starch gel undergoing liquefaction due to alpha-amylase activity.

ICC STANDARD No. 108

2. Scope
The method is applicable to cereals or cereal products ranging from very low to very high in alpha-amylase activity. It can also be used for estimating the alpha-amylase activity of additives of fungal and bacterial origin.

3. Definition
Alpha-amylase activity is expressed as a function of alpha-amylase concentration and of the velocity constant for the hydrolytic degradation of limit dextrin.

4. Principle
The decrease with time of the intensity of colour obtained with the diluted iodine solution is used as an index of starch degradation.

ICC STANDARD No. 109/1

1.1. In the case of maize (and whole maize meal) the method for the determination of moisture content differs in some respects from the method for other cereals (and cereal products). In the Standard the variations are indicated by two columns in the description of the method; the right-hand column applies to maize and the left-hand column to other cereals and cereal products. Cereals and Cereal products (+) Maize and whole maize meal
(+) For the sake of simplicity, in following paragraphs the word "product" is used to mean a cereal as well as a cereal product

2. Scope
This method can be taken as the standard for the development of methods which are specifically suited to the practical determination of the moisture content of wheat, rice (hulled paddy), barley, maize or whole maize meal, millet, rye and oats, as grains, ground grains, semolina and flour. It is not to be used for the settlement of commercial disputes.

3. Definition
The moisture content of a product is defined as the loss in weight sustained by the material under the conditions specified in this Standard, expressed as a percentage of the weight of the original sample.

4. Principle
Measurement of moisture loss when the material, ground if necessary without change of moisture content, is equilibrated in an anhydrous atmosphere at a temperature between 45 and 50 °C and at a pressure of 1.3 ... 2.7 KPa (10 ... 20 mm Hg).

ICC STANDARD No. 110/1

1.1. In the case of maize (and whole maize meal) the method of determining moisture content differs in some points from the method for other cereals (and cereal products). In the description of the method in the Standard, the variations are given side by side in two columns: the right-hand column applies to maize and the left-hand to other cereals and cereal products.

2. Scope
This method is applicable specifically to: wheat, rice (hulled paddy), maize grains or flour from barley, millet, rye and oats, whole grain, ground grains, semolina and flour.
This method gives unsatisfactory results for brewing barley.
Because of the very high moisture content which can be found in maize sample (Sometimes more than 40 %)and because of the size and structure of the grains, problems arise in the pre-drying and grinding of maize for moisture determination.
For this reason both the practical and the basic reference methods can in this case only be carried out by specialized laboratories.

3. Definition
Moisture content is taken to be the loss in weight, expressed as a percentage of the weight of the original sample, which the product undergoes under the conditions specified in the present ICC Standard No. 110.

4. Principle
Determination of the weight loss suffered by the sample when dried at a temperature of 130 to 133 °C under precisely fixed conditions so that a result is achieved which corresponds to the result is achieved which corresponds to the result obtained using the basic reference method (ICC Standard No. 109, Determination of the moisture content of cereals and cereal products).

ICC STANDARD No. 111

2. Scope
The following method is applicable to grain, flour, cereal products and starch products. For samples with a very low nicotinic acid content (e.g., unenriched flours, starch products) or for those giving highly pigmented extracts (e.g., baked products) the microbiological method is more suitable than the chemical method.

3. Definition
The method is for the determination of nicotinic acid. Nicotinamide and most of the nicotinuric acid are both converted by hydrolysis to nicotinic acid. The method does not attempt to distinguish between compounds as to the origin of the vitamin activity of the sample.

4. Principle
The method is based upon the reaction of nicotinic acid with cyanogen bromide to give a pyridinium compound. The latter undergoes rearrangement yielding derivatives that couple with aromatic amines to produce colured compounds. Under the correct conditions, the optical density of the colour produced is proportional to the nicotinic acid present, and may be measured with a photoelectric colorimeter or a spectrophotometer.

ICC STANDARD No. 112

2. Scope
The following method is applicable to grains, flours, cereal and starch products.

3. Definition
The method makes use of Lactobacillus plantarum (ATCC 8014) as the organism for analysis This organism responds to nicotinic acid, nicotinamide, and nicotinuric acid. The method does not attempt to distinguish which of these compounds is responsible for the vitamin activity of the sample.

4. Principle
The method is based on the observation that Lactobacillus plantarum requires nicotinic acid (or nicotinamide) for growth. Using a basal medium complete in all respects except for nicotinic acid, growth responses of the organism are compared quantitatively in standard and unknown solutions. The acid produced by the organism is measured to determine the extent of growth and thereby the amount of vitamin in the test solution.

ICC STANDARD No. 113

2. Scope
This method is applicable to the determination of the crude fibre value in cereals and cereal products.

3. Definition
By the term "crude fibre" is understood a mixture of largely undigestible substances of vegetable origin obtained as the residue of a precisely defined digestion procedure using acetic, nitric and trichloro-acetic acids. "Crude fibre" consists chiefly of cellulose and other vegetable cell wall substances. The crude fibre value does not represent the absolute content of these components.

4. Principle
After boiling the sample with an acid mixture, the undissolved residue is separated and ignited. The crude fibre value is calculated from the ignition loss.

ICC STANDARD No. 114/1

2. Scope and field of application
This standard specifies a method, using the Brabender Extensograph, for determination of the rheological properties of a wheat flour dough in an extension test. The recorded load-extension curve is used to assess general quality of flour and its response to improving agents.
The method is applicable to flour from wheat (Triticum aestivum L.).

3. References

• ICC-Standard No. 130, Sampling of milling products (semolina, flours, agglomerated flours, and by-products); 1980
• ICC-Standard No. 110/1, Determination of the moisture content of cereals and cereal products (Practical method); 1976
• ICC-Standard No. 115/1, Method for using the Brabender Farinograph; 1991
• ISO 3696, Water for analytical laboratory use - Specification and test methods, 1987

4. Definitions
For the purposes of this standard, the following definitions apply:

4.1. Extensograph water absorption
The extensograph water absorption is the volume of water, expressed in millilitres per 100 g of flour at 14.0 % moisture content, required to produce a dough with a consistency of 500 FU after 5 min mixing, under the operating conditions specified in this standard.

NOTE: This standard specifies the extensograph water absorption. The ICC Standard No. 115/1 specifies the farinograph water absorption, the definition of which differs from that of the extensograph water absorption. According to the experience the extensograph water absorption is approximately 2 % less than the farinograph water absorption.

4.2. Stretching characteristics (of dough).
The stretching characteristics of a wheat flour dough are given by:

• the resistance of the dough to extension, expressed in arbitrary units (Extensograph Units, EU), and
• the extent to which it can be stretched before breaking, expressed in millimetres
• transposition of the chart paper in the recorder, under the operating conditions specified in this standard.

ICC STANDARD No. 115/1

2. Scope and field of application
This standard specifies a method, using the Brabender Farinograph, for the determination of the water absorption of flours and the mixing behaviour of doughs made from them. The method is applicable to flour and meal from wheat (Triticum aestivum L.).
In this standard the word "flour" also means "meal".

3. References

• ICC-Standard No. 130, Sampling of milling products (semolina, flours, agglomerated flours, and by-products); 1980.
• ICC-Standard No. 110/1, Determination of the moisture content of cereals and cereal products (Practical method); 1976.
• ICC-Standard No. 114/1, Method for using the Brabender Extensograph; 1991.
• ISO 3696, Water for analytical laboratory use - Specification and test methods, 1987

4. Definitions
For the purposes of this standard, the following definitions apply:

4.1. Consistency
The consistency is the resistance, measured as torque, expressed in arbitrary units (Farinograph Units, FU), of a dough being mixed in the Farinograph at a specified constant speed.

4.2. Farinograph water absorption
The farinograph water absorption is the volume of water, expressed in ml per 100 g of flour at 14.0 % moisture content, required to produce a dough with a maximum consistency of 500 FU, under the operating conditions specified in this standard.

NOTE: This standard specifies the farinograph water absorption. The ICC Standard No. 114/1 specifies the extensograph water absorption, the definition of which differs from that of the farinograph water absorption.

ICC STANDARD No. 116/1

2. Scope
Applicable to wheat flour.

3. Definition
The degree of sedimentation of a flour suspended in a lactic acid solution during a standard time interval is taken as a measure of baking quality.

4. Principle
Swelling of the gluten fraction of flour in lactic acid solution affects the rate of sedimentation of a flour suspension in the lactic acid medium. Higher gluten content and better gluten quality both give rise to slower sedimentation and higher Sedimentation Test values.

ICC STANDARD No. 117

2. Scope
The following method is applicable to cereals and flour as well as to cereal and starch products.

3. Definition
The method serves for the determination of total thiamine and can be used as a reference method. The actual process of measurement is based on the thiochrome method for free thiamine. Phosphoric acid esters and other bonds with thiamine are broken down during the course of extraction and enzymic break down of the material being examined.

4. Principle
In order to free the thiamine from the natural ester and protein bonds, the material to be examined is digested with sulphuric acid and subsequently treated with a phosphatase preparation. In order to exclude foreign fluorescing material the thiamine is separated from the extract by adsorption. The thiochrome resulting from oxidation with potassium ferricyanide in alkaline solution is extracted with isobutyl alcohol. The intensity of the blue fluorescence of the isobutyl alcohol extract is compared with that of the standard solution. The intensity of fluorescence is measured photoelectrically and fluorescence value of a blank test is subtracted from that of the sample extract.

ICC STANDARD No. 118

2. Scope
Applicable to whole wheat

3. Definition
The Sedimentation Test for wheat requires a special grinding method; wheat samples at a standard moisture content are ground by crushing through corrugated rolls followed by sieving through a standard sieve.

4. Principle
The test is based on the production of a "break" flour whose composition depends strongly on the moisture content of the wheat when it is ground; this dependence is least with soft, low protein wheats and is greatest with hard, high protein wheats.

ICC STANDARD No. 119

2. Scope
The following method is applicable to enriched cereals flours as well as to enrichment mixtures.

3. Definition
The method serves for the determination of free thiamine, which is extractable with acid KCl-solution without digestion. The actual process of measurement is based on the thiochrome method.

4. Principle
Thiamine is extracted with a 25 % solution of KCl in 0.1 M HCl at room temperature. This extraction is found to be complete even in those instances in which an absorbent for the vitamin is present or is produced in the sample during extraction. The thiochrome resulting from oxidation of the filtrate with potassium ferricyanide in alkaline solution is extracted with isobutyl alcohol. The intensity of the blue fluorescence of the isobutyl alcohol extract is compared with that of a standard solution. The intensity of fluorescence is measured photoelectrically and the fluorescence value of a blank test is subtracted from that of the sample extract. The use of the HCl blank results in a considerable saving in time required for analysis. There is little or no interference from sample material and no indication that the samples contain substances capable of quenching thiochrome fluorescence under the conditions of the method. There it is sufficient for measurement and calculation to outline in the assay directions the use of one external or outside standard.

ICC STANDARD No. 120

2. Scope
This standard specifies general conditions relating to mechanical sampling for the assessment of the quality of cereal grains.
This standard does not apply to seed grain.

3. Definitions

3.1. Consignment
The quantity of grain dispatched at one time and covered by a particular contract or shipping document.

3.2. Lot
A stated portion on the consignment which will allow the quality to be assessed.

3.3. Primary sample
A small quantity drawn from the grain-stream at a certain time.

3.4. Bulk sample
The quantity of grain formed by combining and mixing the primary samples drawn from any one particular lot.

3.5. Final lot sample
A sample representing the quality of the lot, obtained by reduction of the bulk sample.

3.6. Laboratory sample
A smaller quantity obtained by careful subdivision of the final lot sample on which analyses will be performed. The processes are described in the relevant methods of analysis.

4. Principle
The principle of the method is to obtain an average sample corresponding in every respect to the average characteristics and composition of the parcel from which it has been drawn.

ICC STANDARD No. 121

Method for using of the Alveograph

2. Scope and field of application
The method is used to assess the rheological properties of a dough prepared from wheat flour using the Chopin-Alveograph. The method is applicable to flour from wheat (Triticum aestivum L.).

3. References

• ICC-Standard No. 130, Sampling of milling products (semolina, flours, agglomerated flours and by-products); 1980
• ICC-Standard No. 110/1, Determination of the moisture content of cereals and cereal products (Practical method); 1976
• ISO 3696, Water for analytical laboratory use - Specification and test methods, 1987

ICC STANDARD No. 122/1

2. Scope
Determination of the starch content of cereals, flour, milling products (bran, wheat-feed) and of some foods (e.g. rolled oats, semolina), potatoes and other starch-containing products. The method is not suitable for determination of the starch content of products with a very low starch level, such as germ or gluten.

3. Definition
According to the method described below, the starch content is that portion of the material under examination, determined by optical rotation as measured by a polarimeter, after dissolving the material in calcium chloride solution.

4. Principle
The soluble, optically active compounds accompanying the substance under examination are extracted with 10 % ethanol and removed by centrifugation. The starch remaining in the residue is dissolved in a boiling calcium chloride solution; dissolved proteinanceous substances are precipitated with Carrez solution (I and II) and filtered off.
The optical rotation of the starch solution in the filtrate is measured and from this the starch content is calculated.

ICC STANDARD No. 123/1

2. Scope
Determination of the starch content of cereals flour, milling products (bran, wheat-feed) and of some foods (e.g. rolled oats, semolina), potatoes and other starch containing products. The method is not suitable for determination of the starch content of products with a very low starch level, such as germ or gluten.

3. Definition
According to the method described below, the starch content is that portion of the substance under examination, the optical rotation of which is measured by means of a polarimeter after dissolving in dilute hydrochloric acid. Any high molecular break-down products of the starch substance present in the material under examination are also considered as starch.

4. Principle
The soluble, optically active compound accompanying the substance under examination are extracted with 10 % ethanol and removed by filtration or centrifugation. The starch remaining in the residue is dissolved in hot, dilute hydrochloric acid, dissolved proteinanceous substances are precipitated with Carrez solution (I and II) and filtered. The optical rotation of the starch solution in the filtrate is measured and from this the starch content is calculated.

ICC STANDARD No. 125

2. Scope
Cereals, cereal products, bread and baked goods, pasta.

3. Definition
The term bacterial count means the number of bacteria which become visible as colonies (9.1.) on or below the surface of a casein-peptone-glucose-yeast extract agar (5.2.) after aerobic incubation at 30 °C for 72 hours.

4. Principle
Since direct counting of the bacteria contained in or on the above mentioned products (2) is impossible, an indirect procedure must be used for their determination. For this purpose the product to be investigated is first mixed with a sterile physiological solution in order to separe out and suspend the bacteria (8.1.) - if necessary after comminution of the product by means of a suitable device according to 6.9.1. or 6.9.2.
A decimal dilution series (8.2.) is prepared from this initial suspension. Aliquots of the dilution stages are transferred to Petri dishes and mixed with a culture medium which at first is still molten (8.4.) After solidification of the agar the individual bacterial cells are fixed and can multiply during incubation and form colonies (8.5.). The number of colonies is determined (9.1.) and given as the "number of bacteria per gramme of the sample" (9.2.).
The accuracy of the method depends on the extent to which it is possible to separate completely the bacterial cells from the substrate, avoid damage to the cells during the necessary handling and obtain a good, even distribution of the cells in the culture medium. Accuracy is also enhanced if the bacterial count is carried out on several sub-samples (three or preferably five).

ICC STANDARD No. 126/1

2. Scope and field of application
This standard specifies a method, using the Brabender Amylograph, for determination of the gelatinization properties of starch, indicated by the viscosity, of a flour-water suspension during heating.
The method is applicable to wheat and rye flours.
The method is also applicable to wheat and rye meals and grain, the latter after appropriate grinding. See 9.1.
In this standard the word "flour" also means meals and ground grains (wholemeal).

3. References

• ICC-Standard No. 101/1, Sampling of grains; 1982
• ICC-Standard No. 130, Sampling of milling products (semolina, flours, agglomerated flours, and by-products; 1980
• ICC-Standard No. 107/1, Determination of the "Falling Number" according to Hagberg-Perten as a measure of the degree of alpha-amylase-activity in grain and flour; 1968
• ICC-Standard No. 110/1, Determination of the moisture content of cereals and cereal products (Practical method); 1976
• ISO 3696, Water for analytical laboratory use - Specification and test methods, 1987.

ICC STANDARD No. 127

2. Scope
Applicable to cereal flours.

3. Definition
The weight fraction, in a flour sample, of particles, which, by their sedimentation rate, correspond to equivalent spheres of chosen diameters.

4. Principle
The Andreasen method assumes that particles will sediment at a rate dependent on their size and further assumes the validity of Stoke´s Law in this respect.

ICC STANDARD No. 128/1

2. Scope
The method can be used for all products containing starch (e.g. cereals, flour, semolinas, bran flakes, germs, gluten, etc.), but not if the sample contains glycogen. According to the method described below, the starch content is that portion of the sample that can be determined as glucose after enzymatic decomposition with amyloglucosidase, the sample being previously extracted, where necessary, with 40% ethanol.

3. References

• ICC Standard No. 101/1, Sampling of Grain
• ICC Standard No. 110/1, Determination of the Moisture Content of Cereals and Cereal Products (Practical Method)
• ICC Standard No. 120, Mechanical Sampling of Grain
• ICC Standard No. 130, Sampling of Milling Products (semolina, flours, agglomerated flours and by-products)
• ICC Standard No. 138, Mechanical Sampling of Milled Cereal Products

ICC STANDARD No. 129

2. Scope
This method is applicable to the determination of the proportions of vitreous and not fully vitreous kernels in durum wheat (Triticum durum L.).

3. Definition

The term vitreousness applies to the proportion by weight of vitreous durum wheat kernels in 100 g of a sample as prepared for "Besatz"-analysis according to ICC Standard No. 102/1 (see section 8).

3.1. As (fully) vitreous pass only durum wheat kernels, which do not disclose the least trace of farinaceous endosperm under the described procedural conditions.

3.2. All the other durum wheat kernels count as not fully vitreous.

3.3. So-called "washed" durum wheat kernels (grains lavés) have, caused by the effect of moisture on the grain envelops, acquired a paler, dull, less-transparent external appearance. Outwardly they thus resemble farinaceous kernels. However, the vitreousness of the endosperm is not necessarily impaired. Kernels of this sort have therefore to be cut for evaluation.

3.4. Broken, insect-damaged, frost-damaged or sprouted durum wheat kernels are also separated into "vitreous" and "not fully vitreous" fractions. The vitreous portions are then put together and registered as the new fraction of "damaged vitreous durum wheat kernels".
The not fully vitreous portions are put together with the fraction of undamaged, not fully vitreous durum wheat kernels.

3.5. Kernels of aestivum wheat (vulgare wheat, soft wheat, Triticum aestivum) of every quality are put together in one fraction.

4. Principle
The fractions defined under section 3 are separated by hand after external inspection of each individual kernel with the naked eye. A light-screening device is not to be used. All kernels, which are not, beyond doubt, recognizable form the outside as fully vitreous, have to be cut transversally with a scalpel and evaluated according to the appearance of the sectional areas of the endosperm. This is particularly important in the case of "washed" kernels (grains lavés) with less transparent envelops.

ICC STANDARD No. 130

2. Scope
This standard specifies general conditions relating to sampling for the assessment of the quality and condition of milled products from cereals in powder, particulate or agglomerated form and milling byproducts.
This standard does not apply to whole unprocessed cereal grains, to seed grains or to partially milled cereals which retain the form of the original material ¹⁾. Starches and oils obtained from cereals or pulses are also excluded from the scope of this Standard.
1) For the sampling of cereals as grain, see ICC No. 101/1, Cereals Sampling (as grain). This method is also suitable for the partially milled cereals mentioned.

3. Definitions
Terms used in this standard have the following definitions:

3.1. Consignment: The quantity of product despatched or received at one time and covered by a particular contract or shipping document.

3.2. Lot: A stated portion of the consignment assumed to be of uniform characteristics which will allow the quality and condition to be assessed.

3.3. Primary sample: A small quantity of product taken from a single position in the lot. A series of primary samples is drawn from different parts of the lot which when bulked will be representative of the lot.

3.4. Bulk sample: The quantity of product formed by combining and mixing the primary samples drawn from any one particular lot.

3.5. Final lot sample: A sample representing the quality and condition of the lot, obtained by reduction of the bulk sample and intended for analysis or other examination.

3.6. Laboratory sample: A small quantity obtained by careful sub-division of the final lot-sample on which analyses will be performed by processes which are described in the relevant methods of analysis.

4. General

4.1. Samples shall be drawn jointly by sampling superintendents appointed by buyers and sellers, or by a sampling superintendent appointed jointly.

4.2. Samples shall be fully representative of the lots from which they are drawn. Therefore, as the composition of the lot may be drawn and carefully mixed, thus giving a bulk sample from which are obtained, by successive divisions, the final lot samples. If the lot consists of a number of freight containers, samples shall be drawn from each freight container.

4.3. It is essential that a product which is sea-damaged or otherwise damaged in transit or out of condition shall be kept separate from the sound product and sampled separately. Samples of the unsound material shall not be mixed with samples of sound material.

4.4. Special care is necessary to ensure that all sampling apparatus is clean, dry and free from foreign odours.
Sampling shall be carried out in such a manner as to protect the samples, the sampling instruments and the containers in which the samples are placed from adventitious contamination such as rain, dust, etc.

ICC STANDARD No. 131

2. Scope
This method is applicable for untreated flour, experimentally of commercially milled from wheat for the production of yeast raised bread. It may be expected to consistently rank flour samples in order of their relative baking quality. To obtain any more absolute information on the baking quality of a given flour or flours it is necessary to include some standard of quality in the series of test bakes so that results may be compared with those for the standard.

3. Principle
The baking method calls for high speed dough mixing and a short fermentation time. A dough is made in a specified mixer from flour, water, dry yeast, salt, sucrose, ascorbic acid and, where necessary malt flour. Dough pieces are scaled rounded, rested 30 min, sheeted and moulded, placed in tins, proofed 50 min and baked. Dough handling properties are noted. The steps involved in the test are illustrated schematically in Figure 1 and an example schedule is shown in Table I. The loaves are evaluated the following day for volume, shape, crust color, crumb structure and crumb texture.

4. Formula

NOTE: Where limited amounts of flour are available, the test may be carried out using a minimum of 600 g flour to produce two (250 g flour) loaves instead of three. Appropriate modification would have to be made to the weights and calculations shown in Sections 4,7,9.3,9.5 and Table II.

ICC STANDARD No. 132

2. Scope
Applicable to cereals, cereal products and other plant materials.

3. Principle
Sucrose after repeated extraction with hot 80 % ethanol is hydrolysed by invertase, liberated glucose is estimated by glucose-oxidase, free glucose if present can be determined before inversion.

4. Reagents

4.1. Standard D-Glucose solution: Dissolve 400 mg of pure anhydrous D-glucose in distilled water and dilute to a volume of 1 000 ml with water. This solution must be prepared 4 h before use to allow time for complete mutarotation. Store at 4 °C.

4.2. Standard sucrose solution: Dissolve 500 mg of pure anhydrous sucrose in distilled water and dilute to a volume of 500 ml with water. Store at 4 °C.

4.3 "TRIS" buffer: Dissolve 61 g of tris (hydroxymethyl) amino-methane in 85 ml 5 M hydrochloric acid and dilute to a volume of 1 000 ml with distilled water. Store at 4 °C.

4.4 Enzyme-Buffer-Chromogen Mixture

4.4.1 Glucose oxidase solution: Dissolve 25 mg of glucose oxidase (EC 1.1.34, type I from Aspergillus niger, approx. 15 000 - 20 000 units per mg from solid, Sigma Chemical Co., St. Louis, Missouri, ref. 6.6125) in 25 ml of "Tris" buffer. Glucose oxidase from Boehringer, degree of purity II, ref. 15 424 E.G.A.C., specific activity 20 U/m g may also be used.

4.2.2. Peroxidase solution: Dissolve 15 mg of peroxidase (EC 1.11.17, type I from horseradish, activity approx. 60. Purpurogalin (20 second) units/mg, Sigma, ref P 8125, in 25 ml of "Tris" buffer. Peroxidase from Boehringer, degree of purity II, ref L5 302 E P A B, specific activity approx. 36 U/mg (measured with guiacol) may also be used.

4.4.3. Chromogen solution: Dissolve 50 mg o-Dianisidine Di_HCl (3,3 Dimethoxy Benzidine Di_HCl) in 10 ml of 80 % ethanol of water, Sigma, ref. D 3252.

Solution 4.4.1. and 4.4.2. can be kept at -5 °C and are stable, without loss of activity, for at least 10 days. The chromogen can be stored at 4 °C. A chromogen from MERCK, 3,3 Dimethoxy Benzidine Di_HCL, ref. 820 489 may also be used. The reagent mixture is prepared just prior to use by mixing 20 ml of solution 4.4.1., 5 ml of solution 4.4.2. and 0.5 ml of solution 4.4.3 and diluting to 125 ml with "Tris" buffer.

4.5. Invertase solution: (EC 3.2.1.26, type VI from yeast, activity 200 units per mg solid, Sigma, ref. 15 875). Prepare a solution containing 1 mg of invertase per 1 ml. Invertase from Boehringer ref. 15 067 E.F.A.F., specific activity: approx. 150 U/mg dry powder (25 °C) may be used also.

4.6. Acetate buffer (2 M, pH 4.7): Dissolve 164 g of anhydrous sodium acetate and 120 ml of acetic acid. Dilute to a volume of 1 000 ml with distilled water.

4.7. Hydrochloric acid, 5 M

4.8. 80 % ethanol

4.9. Carrez solution I and II: Carrez solution I: Dissolve 23.8 g of zinc acetate trihydrate and 3 g of glacial acetic acid in water and dilute to a volume of 100 ml with water. Carrez solution II: Dissolve 10.6 g of potassium ferrocyanid in water and dilute to a volume of 100 ml with distilled water.

ICC STANDARD No. 133

2. Scope
Feedstuffs and cereals or cereal products for the production of feedstuffs.

3. Definition
Bacterial count means the number of those aerobic and facultatively anaerobic mesophilic bacteria which become visible as colonies on or below the surface of the culture substrate, when an aliquot of a suspension of the product to be examined has been transferred to a bacterial nutrient medium, according to 5.2., and incubated aerobically at 30 °C for 5 days (9.1.).

4. Principle

It is not possible to carry out a direct count of the bacteria in or on the product to be examined. For this reason an indirect method must be used to detect them. The product is first mixed with a sterile physiological dilution fluid, in order to separate and suspend the bacteria (8.1.), if necessary after grinding the product with grinding apparatus according to 6.9.1. or 6.9.2. A series of tenfold dilutions is made from this initial suspension (8.2.). Aliquot parts of these dilution stages are transferred to petri dishes (8.3.) and mixed with a culture medium which at first is molten (8.4.). When the agar has solidified, the individual bacterial cells are fixed and can multiply and form colonies in these positions during incubation (8.5.). The number of colonies is determined (9.1.) and described as "number of bacteria per g sample" (9.2.).

The accuracy of the method depends on how far one is successful in completely separating all the bacterial cells from the substrate, in avoiding damage to the cells during the necessary manipulations, and obtaining an even distribution of the cells in the culture medium. Greater accuracy is obtained if the count is determined on several subsamples (three, or preferably five).

ICC STANDARD No. 134

2. Scope
Feedstuffs and cereals or cereal products for making feedstuffs.

3. Definitions
Mould or yeast count means the number of those aerobic mesophilic colony-forming units which become visible as colonies when an aliquot of a suspension of the product to be examined has been transferred to a fungal nutrient medium according to 5.2. and incubated aerobically at 25 °C for 5 days (9.1.).

4. Principle
It is not possible to carry out a direct count of the microbial organisms present in or on the product to be examined. Therefore an indirect method must be applied to detect them. To do this the product to be examined is first mixed with a sterile physiological dilution fluid (5.1.) to separate and suspend the organisms (8.1.), if necessary after grinding the product with grinding apparatus according to 6.9.1. or 6.9.2. A series of tenfold dilutions is made from this initial suspension (8.2.). Aliquot parts of these dilution stages are transferred to petri dishes (8.3.) and mixed with a nutrient medium which is still molten at first (8.4.). When the agar has solidified the individual cells are fixed and they can multiply and form colonies in these positions during incubation (8.5.). The number of colonies is determined (9.1.) and described as "number of moulds and yeasts per g sample" (9.2.). The accuracy of the method depends on how far one is successful in completely separating all the microbial organisms from the substrate, in avoiding damage to the cells during the necessary manipulations and obtaining an even distribution of cells in the culture medium.
Greater accuracy is obtained if the count is determined on several subsamples (three, preferably five).

ICC STANDARD No. 135

2. Scope
The subject of this standard is the description of a method for the determination of the moisture content of maize in whole kernels.
In view of the very high moisture content exhibited by samples of maize (in some cases over 40 %) and because of the size and structure of the kernels, there are certain problems associated with predrying and grinding when determining the moisture content of maize. Therefore both the basic reference method and the practical method for ground kernels which are described in ICC Standards No. 109/1 and No. 110/1 can only be used by special laboratories. Whole kernels are used for the method described here, which eliminates predrying and grinding. The method is easier to use and permits testing to be carried out in series. Under no circumstances can the standard be used for the adjustment or checking of instruments for moisture determination.

3. Definition
Moisture content is defined as the relationship, expressed in percent, between the loss of weight which the product undergoes under the conditions described in this standard and the initial weight of the sample. In contrast to the results of the basic reference method which is described in ICC Standard No. 109/1, the differences between the results are usually less than 0.5 g moisture per 100 g sample.

4. Principle
Drying of the whole kernels at a temperature of 130 °C - 133 °C under normal atmospheric pressure in 38 hours.

ICC STANDARD No. 136

2. Scope and field of application
This International Standard specifies a method for the determination of the total fat content of cereals and cereal products intended for human consumption, including baked products and pasta.

3. References

• ICC Standard No. 110/1: Determination of moisture content of cereals and cereal products (Practical method)
• ICC Standard No. 101/1: Sampling of grains
• ICC Standard No. 130: Sampling of milled products
• ICC Standard No. 135: Determination of the moisture content of whole maize kernels

4. Definition
Total fat content: The whole of the substances extracted by hexane under the operating conditions specified in this International Standard, and expressed as a percentage by mass of the product as received.

ICC STANDARD No. 137/1

Mechanical Determination of the Wet Gluten Content of Wheat Flour (   Glutomatic)

2. Scope

2.1. This international standard specifies a method for the mechanical determination of the wet gluten content of wheat flour.
2.2. This method is applicable to different wheat flours (commercial and experimental flours) but not to wheatmeal.

3. Definition
Wet gluten in wheat flour is a plastic-elastic substance consisting of gliadin and glutenin and obtained by the method specified in this international standard.

4. Principle
A dough is prepared from a flour sample by adding a buffered sodium chloride solution; the wet gluten is isolated by washing this dough with sodium chloride solution. The residual water adherent to the gluten is removed by centrifugation and the remainder weighed.

ICC STANDARD No. 138

Introduction

Correct mechanical sampling is an operation that requires most careful attention. Emphasis cannot therefore be too strongly laid on the necessity of obtaining a properly representative sample of milled products. Careless or inaccurate mechanical sampling lead to misunderstanding and unwarranted financial adjustments.

The procedures given in this standard are recognized as good practice and it is strongly recommended that they be followed whenever practicable. It is difficult to lay down fixed rules to be followed in every case, and particular circumstances may render some modification of the method desirable, for example if it is desired to check the uniformity of a consignment by the examination of individual primary samples.

In certain areas there are widely recognized trade associations which prescribe rules for the sampling procedures to be used in contracts under their auspices. In no case will be methods described in this Standard override the rules laid down in such contracts, or the rules of official inspecting organizations.

2. Scope and field of application
This Standard specifies general conditions relating to the automatic sampling by mechanical means, for assessment of quality of milled cereal products intended for human consumption.
It is applicable to milled cereal products moving in bulk.
It is not applicable to commodities in sacks or in packages, to static bulks in wagons, ships, bulk tankers, silos or warehouses.

3. Definitions
For the purpose of this standard, the following definitions apply:

3.1. Consignment: The quantity of product dispatched or received at one time and covered by a particular contract or shipping document. It may be composed of one or more lots.

3.2. Lot: A part of a consignment or a consignment, moving past the sampling point during a stated period of time, with presumed uniform characteristics and to which a given scheme of investigation can be applied.

3.3. Primary sample: A small quantity of product taken from the lot at a single point in time or during a stated short period of time.
A series of primary samples should be taken at a number of points in time or during a series of short periods of time such that, when bulked, they will be representative of the lot.

3.4. Bulk sample: The quantity of product formed by combining and mixing the primary samples taken from a specific lot.

3.5. Final lot sample: A sample representing the quality of the lot, obtained by reduction of the bulk sample.

3.6. Laboratory sample: The quantity of product obtained by careful subdivision of the final lot sample and intended for analysis or other examination.

4. General

4.1. Arrangements for mechanical sampling shall be made jointly by sampling superintendents appointed by the interested parties, or by a sampling superintendent appointed jointly.

4.2. The purpose of mechanical sampling is to obtain a sample corresponding in characteristics and composition with the lot from which it was taken. Therefore, the mechanical sampling device, having been installed, suitably adjusted and set in operation, shall automatically take a primary sample or a series of primary samples from a lot, without human intervention, such primary sample or primary samples taken continuously, or intermittently and repeatedly.

4.3. It is essential that a product which is sea-damaged or otherwise damaged in transit or out of condition is kept separate from the sound product and sampled separately. Samples of the unsound material shall not be mixed with samples of the sound material.

4.4. Special care is necessary to ensure that all parts of the automatic sampler are clean, dry and free from foreign odours.

4.5. Sampling shall be carried out in such a manner as to protect the samples, the mechanical sampler, the containers in which the samples are placed, from adventitious contamination such as rain, dust, etc.

ICC STANDARD No. 139

2. Scope and field of application
Cereals, cereal products, bread and baked goods, pasta.

3. Definition
The fungus germ count is the number of such aerobic mesophilic colony-forming germs as become visible as colonies (9.1.) after transfer of an aliquot of a suspension of the product under investigation into a fungal culture medium acc. to 6.2. and subsequent incubation at 25 °C for 120 hours.

4. Principle

4.1. Since a direct count of the microbial germs present in and/or on the products listed above (2) is impossible, an indirect method has to be used.

4.2. The product under investigation is treated with a sterile physiological solution by which the germs are separated out and suspended (8.1.), if necessary after grinding of the product by means of a homogeniser acc. to 5.2.1. or 5.2.2.

4.3. A decimal dilution series (8.2.) is prepared from the initial suspension.

4.4. Aliquots of the dilution stages are transferred into Petri dishes (8.3.) and mixed with a culture medium (8.4.), which, at this stage, is still liquid.

4.5. Once the agar has solidified, the individual germs and colony-forming entities are fixed in their places, where they can multiply and form colonies during incubation (8.5.).

4.6. After the end of incubation the number of colonies is determined (9.1.) and designated as the "number of fungal (mould, yeast) germs per gramme of sample" (9.2.).

4.7. The accuracy of the method depends on the extent to which it proves possible to separate the microbial germs from the substrate, to avoid damage to the germs during the necessary handling, and to obtain a good, even distribution of the germs in the culture medium. Accuracy will also be enhanced, if the microbial count is carried out on several (two to three) sub-samples.

ICC STANDARD No. 140

2. Scope
The method is suitable for determining the bran content of cereals.

3. Definition
Bran content is taken to be the residue left after particle singe reduction and the combined effect of fatty solvents, heat, amylolytic and proteolytic enzymes.

4. Principle
Fat is extracted with acetone/ether from the ground material, which is then reduced to paste and hydrolysed in separate stages with temperature-stable bacterial alpha-amylase and bacterial alkaline protease. The fat is again extracted from the residue which is determined gravimetrically.

ICC STANDARD No. 141

2. Scope
These methods specify reference methods for the determination of total mercury in cereals and cereal products.

3. Field of Application
The methods described are applicable to the determination of the total mercury content of foodstuffs and biological materials to 0.01 mg/kg. In order to determine lower contents of total mercury, a concentration step should be applied as described below (5.3.).

4. Definition
Total mercury content of cereals (foodstuffs and biological materials): the mercury content determined according to the procedures described in this standard and expressed in milligram per kilogram substance as is.

ICC STANDARD No. 143

2. Scope
This International Standard specifies a method for the identification of the variety of a given lot of soft or hard wheat, in the form of individual ground kernels, flour, farina or semolina, by the separation of gliadin proteins.

3. Definition
The protein composition of wheat results from direct genetic control and in general is not affected by environmental conditions (e.g. location of year of growth). In addition, because wheat is essentially a self-pollinating plant, the protein composition of the different varieties of wheat remains stable for several plant generations. Therefore, the protein composition of a wheat can be used to characterize and thus to identify its variety.
Protein profiles can be obtained by carrying out polyacrylamide gel electrophoresis (PAGE) separations of the wheat gliadins. The polyacrylamide gels are stained to make the separated protein components visible. If such protein profiles are established for all wheat varieties which can be expected to occur in a particular region (i.e. a variety catalogue is prepared), the identification of an unknown variety of wheat can be established by reference to such a catalogue. Such a practice has been thoroughly characterized and is in common use in numerous countries.

4. Principle
The separation of gliadin wheat protein by polyacrylamide gel electrophoresis (PAGE) into 1,5 mm thick slab gels containing aluminium lactate buffer pH 3.1.

ICC STANDARD No. 144

2. Scope
Cereals, Cereal Products, Bread and Baked Goods, Pasta

3. Definition
The standard plate count of the spores of mesophilic bacteria is the number of those aerobic mesophilic bacteria that form colonies (9.1) on or under the surface of the culture substrate after any vegetative cells present have been killed, after heat activation of Bacillus spores, transfer of a certain part of a suspension of the product under investigation into a caseine peptone-glucose-yeast extract-agar and subsequent incubation (30 °C for 72 hours).

4. Principle

4.1. Since direct counting of the Bacillus spores contained in or on the product under investigation is impossible, an indirect method has to be used.

4.2. The product under investigation is first mixed with a sterile physiological solution (6.1) in order to separate and suspend the microorganisms (8.1), where necessary, after grinding the product by means of blending equipment according to 5.2.1, 5.2.2 or 5.2.3.

4.3. A tenfold dilution series is made from this initial suspension (8.2).

4.4. Aliquots of the dilution stages are subjected to heat treatment to inactivate the vegetative cells.

4.5. The pasteurized diluents are transferred into sterile Petri dishes and mixed with the culture substrate.

4.6. In the course of incubation the spores may germinate and form colonies on and under the surface of the culture substrate.

4.7. After the end of incubation the "number of spores of mesophilic bacteria per gram of sample" is calculated from the number of colonies present on and under the surface of selected plates of the culture substrate (9.1).

ICC STANDARD No. 145

2. Scope and field of application
This ICC Standard describes the determination of the acidity of wheat, rye barley, and rice, and their milling products by the method of Schulerud.

3. Definition
1 acidity unit corresponds to 0.01 gram-equivalent of acid per kg of product, extracted under specified conditions.

4. Principle
Grinding of the product, if necessary, extraction by means of 57 % (m/m) ethanol, centrifugation of the extract, and titration with standard alkali.

ICC STANDARD No. 146

2. Scope
Cereals, Cereal Products, Bread and Baked Goods, Pasta

3. Definition
The yeast and mould count is the number of those colonies, that become visible (9.1) after transfer of an aliquot of a suspension of the product under investigation to the surface of a suitable agar medium (6.2), spreading and subsequent incubation at 25 °C for 5-7 days.

NOTE: The distinction between yeast and mould colonies is made by macroscopic examination. Under the conditions described in this International Standard moulds usually develop flat or fluffy spreading colonies often with coloured fruiting or sporing structures. Yeasts develop matt or shiny round colonies usually having a regular outline and a more or less convex surface.

Very small colonies (after 5 to 7 days) can be due to bacteria. Check by microscopic examination.

4. Principle

4.1. Since direct counting of the yeasts and moulds contained in or on the product under investigation is impossible, an indirect method has to be used.

4.2. The product under investigation is first mixed with a sterile physiological solution (6.1) in order to separate and suspend the microorganisms (8.1), where necessary, after grinding the product by means of blending equipment according to 5.2.1, 5.2.2 or 5.2.3.

4.3. A tenfold dilution series is made from this initial suspension (8.2).

4.4. Aliquots of the dilution stages are transferred onto the surface of a culture substrate that has previously been poured into sterile Petri dishes and has solidified (6.2.2).

4.5. The transferred suspension containing the yeasts and moulds is uniformly spread over the surface of the culture substrate.

4.6. In the course of incubation the yeasts and moulds can multiply and form colonies on the surface of the culture substrate.

4.7. After the end of incubation the "number of yeasts and moulds per gram of sample" is calculated from the number of colonies present on the surface of selected plates of the culture substrate (9.1).

ICC STANDARD No. 147

2. Scope
Cereals, Cereal Products, Bread and Baked Goods, Pasta

3. Definition
The bacteria count is the number of those colonies, that become visible due to the growth of mesophilic, either aerobic or facultatively anaerobic microorganisms after transfer of an aliquot of a suspension of the product under investigation to the surface of a suitable agar medium (6.2), spreading and subsequent incubation at 30 °C for 3 days (9.1).

4. Principle

4.1. Since direct counting of the bacteria contained in or on the product under investigation is impossible, an indirect method has to be used.

4.2. The product under investigation is first mixed with a sterile physiological solution (6.1) in order to separate and suspend the microorganisms (8.1), where necessary, after grinding the product by means of blending equipment according to 5.2.1, 5.2.2 or 5.2.3.

4.3. A tenfold dilution series is made from this initial suspension (8.2).

4.4. Aliquots of the dilution stages are transferred onto the surface of a culture substrate that has previously been poured into sterile Petri dishes and has solidified (6.2.2).

4.5. The transferred suspension containing the microorganisms is uniformly spread over the surface of the culture substrate.

4.6. In the course of incubation the bacteria can multiply and form colonies on the surface of the culture substrate.

4.7. After the end of incubation the "number of bacteria per gram of sample" is calculated from the number of colonies present on the surface of selected plates of the culture substrate (9.1).

ICC STANDARD No. 151

2. Scope
Applicable to durum wheat wholemeal.

3. Definition
The degree of sedimentation of a durum wheat meal suspended in a lactic acid-sodium dodecyl sulfate (SDS) medium during a standard time of settling. The SDS-value depends on the protein quality providing an indication of durum wheat gluten strength.

4. Principle
The swelling capacity of the gluten proteins of durum wheat wholemeal affects the rate of sedimentation of a meal suspension in the SDS medium. Better quality gluten gives rise to slower sedimentation and higher SDS-values.

ICC STANDARD No. 152

2. Scope
The method describes the determination of the yellow pigment content of raw materials for pasta. It is suitable not only for semolina and flour but also for pasta, without or with egg. To wheat and wholemeal products it is applicable only with reservations, since interfering pigments of the seed coats are also extracted.

3. Definition
The yellow pigment content is an essential quality factor of raw materials for pasta. It is defined as the content of extractable carotenoids of the endosperm calculated as mg -carotene in 100 g dry matter.

4. Principle
Extraction of the carotenoids at room temperature with water saturated n-butanol and photometric evaluation of the optical density of the clear filtrate against -carotene standard.

ICC STANDARD No. 153

2. Scope and field of application
This ICC Standard specifies a method for the assessment of the amount of total organic matter (TOM) found in washing water after spaghetti cooking, following a standard procedure. The method applies to spaghetti only.

3. Definition
The total organic matter (TOM) is the amount of organic matter found in washing water after spaghetti cooking following a standard procedure.

4. Principle
The method is based on washing the drained cooked spaghetti with water at room temperature to remove the substance coating the surface of spaghetti cooked for a fixed time. An aliquot of the washing water is evaporated. The organic matter in the residue is determined by titration with ferrous ammonium sulphate in excess of potassium dichromate. High quantities of organic matter indicates poor cooking quality.

ICC STANDARD No. 154

2. Scope
This ICC Standard specifies a method for the determination of total cadmium and lead in cereals and cereal products.

3. Field of application
This method is suitable for the analysis of total cadmium and lead content in cereals and cereal products. It can also be applied to non-fatty foodstuffs (fat content <= 10 %) and biological materials.

4. Definition
Total cadmium and lead content in cereals, cereal products and non fatty foodstuffs and biological materials determined according to the procedure described in this standard is given in milligrams per kilogram as is.

ICC STANDARD No. 155

Determination of Wet Gluten Quantity and Quality (Gluten Index ac. to  ) of Whole Wheat Meal and Wheat Flour (Triticum aestivum)

2. Scope
This description specifies a method for the mechanical preparation of wet gluten and the subsequent determination of the Gluten Index according to Perten, as a measure of gluten characteristics. The method is applicable to whole wheat meals and wheat flours.

3. Definition
Wet gluten in wheat flour is a visco-elastic substance made of gliadin and glutenin, which is obtained by means of the specified method contained in this international standard. The Gluten Index is a measure of the gluten characteristics, which indicates whether the gluten is weak, normal or strong.

4. Principle
Gluten separated from whole wheat meal or wheat flour by the Glutomatic equipment is centrifuged to force wet gluten through a specially constructed sieve under standardized conditions. The total weight of the gluten is defined as gluten quantity. The percentage of wet gluten remaining on the sieve after centrifugation is defined as the Gluten Index. If the gluten is very weak all of the gluten may pass through the sieve, the Gluten Index is 0. When nothing passes through the sieve, the Index is 100.

ICC STANDARD No. 156

2. Scope
The method is designed for the determination of the total dietary fibre content of food in general and of cereal foodstuffs in particular.

3. Definition
The content of total dietary fibre is the amount of organic constituents, which are gravimetrically measured after extraction and enzymatic digestion of non-fibre material according to the described method. Dietary fibre substances primarily are hemicelluloses, pectins, other non-starch hydrocolloids, resistant starch, cellulose and lignin.

4. Principle
Samples (duplicates at least, but preferably two duplicates), defatted if necessary (see section 7.1), are gelatinized in the presence of heat stable alpha amylase, and then enzymatically digested with protease and amyloglucosidase to remove digestible protein and starch. Four volumes of ethanol are added to precipitate soluble dietary fibre. Total residue is filtered off and washed with ethanol and acetone. The residue is weighed after drying. The remaining material is analysed for protein and ash content, respectively. Subtracting the amounts measured for protein, ash and a blank control from the dry weight of the filtered residue yields a value for total dietary fibre content.

ICC STANDARD No. 157

2. Definition
The ash content of a flour is determined by measuring electrical conductivity on flour extracts, using the model "log (ash) = A + B log (conductivity)". A and B are calculated on a basis of pre-determined ash and conductivity values of a range of flours, using a specific conductivity equipment.

3. Scope
The method is applicable to sifted wheat flour and ground wheatmeal.

4. Equipments/Reagents

4.1. Instruments for measuring conductivity of a range of 0.00 m S/cm - 1999 m S/cm (Tetra Con or similar). If possible - the instrument should conform to the OIML Recommendation No. 68 "Calibration Method for Conductivity Cells", which can be obtained at the ICC General Secretariat.

4.2. Centrifuge (capable of centrifuging at 4000 rpm)

4.3. Centrifuge tubes (50 ml)

4.4. Water bath, for temperatures of 20 °C and higher

4.5. Electrically heated muffle furnace, capable of temperatures of 900 °C (+ 10 °C), with temperature control/indication and sufficient ventilation.

4.6. Ashing crucibles (preferably gold or platinum, alternatively quartz or porcelain).

4.7. Balance (accuracy 0.1 mg)

4.8. Deionized water.

4.9. KCl-Solution (for calibration of the conductivity instrument).

ICC STANDARD No. 158

2. Scope
The description specifies a method for the mechanical preparation of wet gluten and the subsequent determination of the Gluten Index as a measure of gluten characteristics. The method is applicable to durum whole meals and semolina.

3. Definition
Wet gluten in durum wheat is a plastic-elastic substance made of gliadin and glutenin, which is obtained by means of the method specified below. The Gluten Index is a measure of the gluten strength, which indicates whether the gluten is inadequate, sufficient, average or excellent.

4. Principle
Gluten separated from durum whole meals or semolina by Glutomatic (  ) is centrifuged to force wet gluten through a specially constructed sieve under standardized conditions. The percentage of wet gluten remaining on the sieve after centrifugation is defined as the Gluten Index. If the gluten is very weak all of the gluten may pass through the sieve, the Gluten Index is 0. When nothing passes through the sieve, the Index is 100.

ICC STANDARD No. 159

2. Scope
This method is applicable to ground wheat and flour.

3. Principle
NIR reflectance spectroscopy is a rapid instrumental technique for the analysis of cereals both in the laboratory and on-line. It is based on absorption of NIR energy at specific wavelengths by peptide linkages between amino acids of protein molecules and at reference wavelenghts. Mathematical processing of the spectral data and calibration against a suitable reference method enables the protein content to be determined. Inclusion of a measurement at a wavelength corresponding to an absorption by water enables the result to be corrected automatically to a dry weight basis or on a standard moisture basis.

4. Apparatus

4.1. Near infrared fixed filter instrument or monochromator capable of measurement at 2230, 2180, 2100, 1940 and 1680 nm.

4.2. Grinding mill. Screen sizes of 0.5, 0.8 or 1.0 mm mesh are acceptable.

4.3. A personal computer with multiple regression software (if not incorporated in 4.1.).

ICC STANDARD No. 161

2. Scope

This standard specifies a method, using the Rapid Visco Analyser (RVA), developed and supplied by Newport Scientific, Warriewood, NSW Australia, for rapid determination of the pasting properties of starch, indicated by the viscosity of a flour-water suspension at high temperature and as influenced by the alpha-amylase activity present in flour.

The method is applicable to wheat and rye flours.

This method is also applicable to wheat and rye meals and grain, the latter after appropriate grinding. See 9.1.

In this standard the word "flour" also means meals and ground grain (wholemeal).

3. References

• ICC-Standard No. 101/1, Sampling of grains;
• ICC-Standard No. 130, Sampling of milling products (semolina, flours, agglomerated flours, and by-products);
• ICC-Standard No. 107/1, Determination of the "Falling Number" according to Hagberg-Perten as a measure of the degree of alpha-amylase activity in grain and flour;
• ICC-Standard No. 110/1, Determination of moisture content of cereals and cereal products (practical method);
• ISO 3696, Water for analytical laboratory use - specification and test methods.

4. Definition
The viscosity of the gelatinised starch undergoing liquefaction in the flour-water suspension, simultaneously heated to 95 °C in the Rapid Visco Analyser, is measured as the current necessary to rotate the stirrer at constant speed after three minutes of test (in the 180th second) and expressed in arbitrary units as "Stirring Number".

ICC STANDARD No. 162

2. Scope
The method is applicable to native and modified starch, to wheat and rye flours and meals and to all cereal grains, the latter after appropriate grinding. See 9.1. The viscosity of a starch-water or flour-water slurry is determined when the starch is gelatinised by heating the slurry, and altered by the action of -amylase present in or added to the flour or starch. In this standard the word "flour" also means meals and ground grain (wholemeal).

3. References

• ICC-Standard No. 101/1, Sampling of grains
• ICC-Standard No. 130, Sampling of milling products (semolina, flours, agglomerated flours, and by-products);
• ICC-Standard No. 107/1, Determination of the "Falling Number" according to Hagberg-Perten as a measure of the degree of alpha-amylase activity in grain and flour;
• ICC-Standard No. 110/1, Determination of moisture content of cereals and cereal products (practical method);
• ISO 3696, Water for analytical laboratory use - specification and test methods.

4. Definition
The Rapid Visco Analyser (RVA) is a recording viscometer that may be used to determine the pasting properties of, and effect of alpha-amylase on, a starch-water or flour-water suspension during heating and cooling. The peak viscosity is defined as the maximum viscosity that occurs prior to the initiation of sample cooling. The minimum viscosity is the lowest viscosity recorded after the peak viscosity. The final viscosity is the viscosity at the end of the test. All viscosities are measured in Rapid Visco Units (RVU).

ICC STANDARD No. 164

Measurement of Damaged Starch by Using  Enzymic Kit

2. Scope
This text describes a method for determination of damaged starch in flours.

3. Definition
During milling, some of the starch granules present become mechanically damaged, leading to a greater capacity to absorb water and swell, plus increased susceptibility to amylolytic enzymes. Such factor affect the quality of flours. The absorption of starch that becomes damaged can improve baking properties up to a critical level above which properties of flours are negatively affected. Damaged starch is a parameter of flour quality which must be carefully controlled.

4. Field of application
This method is applicable to wheat and other cereal flours and to starches.

ICC STANDARD No. 165

2. Scope
Applicable to wheat and wheat products. The method is applicable to the determination of ochratoxin A in wheat and wheat products at concentrations of 0.4 m g/kg up to 5.0 m g/kg in vegetable material and foodstuffs.

3. References

• ICC-Standard No. 101/1, Sampling of grains
• ICC-Standard No. 130/1, Sampling of milling products
• ICC-Standard No. 110/1, Determination of moisture contents of cereals and cereal products

4. Definition
According to the method described below, ochratoxin A is determined after extraction and acidification using high performance liquid chromatography (HPLC).

ICC STANDARD No. 166

3. Definition
This method determines quantitative (1->3), 1->4) - ß-D-glucan (ß-D-glucan, mixed-linkage ß-D-glucan).

4. Principle
ß-D-glucan is determined using highly purified lichenase and ß-D-glucosidase. ß-D-glucan is specifically hydrolyzed by lichenase to oligosaccharides, which are quantitatively cleaved to glucose by ß-glucosidase. Glucose is measured using glucose oxidase - peroxides - buffer mixture.
Method is rapid procedure for direct, quantitative measurement of (1->3) (1->4)-ß-D-glucan (ß-D-using highly purified lichenase and ß-glucosidase). ß-D-Glucan is specifically hydrolyzed by lichenase to oligosaccharides, which are then quantitatively cleaved to glucose by ß-glucosidase. Glucose is measured using glucose oxidase-peroxidase-buffer mixture.

(see also  )
ICC STANDARD No. 167

3. Definition
Crude protein is a conventional expression of the total content of nitrogen compounds of the analysed product, calculated by multiplying the corresponding nitrogen content by a conversion factor.

4. Principle
4.1. The sample is combusted in an oxygen-rich environment, at about 1000° C, to give oxides of nitrogen which are catalytically reduced to nitrogen. Other products resulting from the combustion phase are removed by selective absorption.
4.2. Nitrogen gas is measured with a thermal conductivity detector.
4.3. Total nitrogen is calculated from the detector response. The detector is calibrated with a known nitrogen standard.
4.4. Automatic combustion analysers rely on a carrier gas, such as helium or carbon dioxide.
 

ICC STANDARD No. 169

3. References
ICC-Standard No. 130, Sampling of milling products (semolina, flours, agglomerated flours, and by-products; 1980
ICC-Standard No.110/1, Determination of the moisture content of cereals and cereal products (Practical method); 1976
ISO 3696, Water for analytical laboratory use - Specification and test methods; 1987

4. Definitions
The Viscograph viscosity is the resistance, measured as torque and expressed in arbitrary units (Brabender Units, BU), of a starch-water suspension heated in the Brabender Viscograph at a constant rate of increase (heating) and decrease (cooling) of temperature and with the bowl rotating at a specified constant rotational speed.
The ”hot-paste” Viscograph viscosity is the viscosity reached under the conditions of the method just before the paste is being cooled.
The ”cold-paste” Viscograph viscosity is the viscosity reached under the conditions of the method after cooling the paste to the final temperature (50°C).

5. Principle
A starch-water suspension is heated at a constant rate of increase and decrease, resp., of temperature in a bowl rotating at a specified constant rotational speed. During heating and cooling, the viscosity of the sample is recorded continuously.
The test involves a temperature program designed to show and characterise the viscosity behaviour of starch as influenced by increasing and decreasing temperatures and by mechanical stirring. The viscosity of starch pastes measured at different stages during their preparation is a guide to their pasting behaviour.
 

ICC STANDARD No. 171

3. References

• ICC-Standard No 130 Sampling of milling products (semolina, flours, agglomerated flours and by -products); 1980.
• ICC-Standard No 110/1 Determination of the moisture content of cereals and cereal products (practical method); 1976.
• ISO 3696, Water for analytical laboratory use - Specification and test method, 1987

4. Definitions
"Physical properties of dough during mixing" means the capacity of dough to maintain a certain level of consistency during the test time on the Consistograph mixer.

5. Principle
A dough is made from wheat flour to which an amount of water, based on the initial moisture content of the flour, is added in order to reach a constant hydration level on a dry matter basis. During the kneading of this dough sample, the pressure on one side of the mixer is continuously monitored. The peak pressure recorded during kneading is used to calculate the water absorption of the flour sample at a given " consistency " (target pressure). In a subsequent test performed at the hydration level previously determined, physical properties of the wheat flour dough are determined.
 

ICC DRAFT STANDARD No. 172

3. Application domain
This method is applicable to standard white flour obtained from T. aestivum coming from a laboratory or an industrial milling. Results concerning wholemeal flour, although they can satisfy the repeatability conditions given in 8, must be interpreted carefully.

4. Standard References
No previous standard references have been found.

5. Principle
Determination of flour starch damage by the measurement of the kinetics of iodine absorption in a liquid suspension, using an Amperometric probe.
 

ICC DRAFT STANDARD No. 173

2. Introduction
Dough behavior during the mixing process is related to many parameters. Some are more related to protein content and quality such as water uptake, dough development time, and dough stability during mixing. Others are related to starch content and quality such as gelatinization, setback, gelling, etc.
By measuring the torque of the dough during mixing with an increase in temperature, the Mixolab makes it possible to have complete information on the sample allowing the user to better understand the wheat or flour characteristics.

3. Application domain
This method is applicable to flour obtained from T. aestivum coming from a laboratory or an industrial mill. It can also be applied to whole meal of wheat ground under standardized conditions.

4. Standard References

• ICC-Standard No 110/1 Determination of the moisture content of cereals and cereal products (practical method); 1976.
• AACC International Approved Method 44-15A Moisture – Air Oven Method

5. Principle
Determination of dough behaviors subjected to mixing stresses and temperature stresses during constant phase, followed by a heating phase, a holding phase at high temperatures, and a cooling phase. Flour is hydrated to reach a maximum consistency (1.1 Nm) during a first phase at 30°C. The dough is mixed between two mixer arms with a rotating speed of 80 rpm. The torque created by the dough between the two arms is registered. Mixing continues as the mixer temperature is raised to 90°C with a temperature increase of 4°C/minute. Temperature is maintained at 90°C for 15 minutes. The mixer bowl is then cooled down to 50°C with a temperature decrease of 4°C/minute. Dough consistency during the entire process is measured as well as dough temperature. The results give indication on the protein strength, starch gelatinisation and retrogradation, enzymatic systems as well as interactions.
 

ICC DRAFT STANDARD No. 174

2. Scope
Applicable to whole grain sorghum.

3. Definitions
To produce sorghum malt, it is necessary that a high proportion of sorghum grains in a batch germinate.

Germinative Energy is the percentage of grains which can be expected to germinate if the batch is malted normally at the time of the test.

4. Principle
Sorghum grains are placed on damp filter paper in closed petri dishes and allowed to germinate at a set temperature for set periods of time.
The percentage of grains that have germinated at the end of each period is calculated.
 

ICC DRAFT STANDARD No. 175

2. Scope
This method is applicable to determination of total defects in consignments of whole grain sorghum intended for human consumption.

3. Definitions
The term total defects applies to all components of a sorghum sample which differ from the normal basic variety, including extraneous matter, filth, blemished grains, diseased grains, broken kernels and other grains.

3.1 Extraneous matter All organic and inorganic material other than sorghum, broken kernels, other grains and filth. Extraneous matter includes loose sorghum seedcoats.

3.2 Filth
Impurities of animal origin including dead insects.

3.3 Blemished grains
3.3.1 Grains which are insect of vermin damaged, of abnormal colour, sprouted, diseased, or otherwise materially damaged.
3.3.2 Diseased grains – grains made unsafe for human consumption due to decay, moulding, or bacterial decomposition, or other causes that may be noticed without having to cut the grains open to examine them.
3.3.3 Insect or vermin damaged grains – Kernels with obvious weevil-bored holes or which have evidence of boring or tunnelling, indicating the presence of insects, insect webbing or insect refuse, or degermed grains, chewed in more than one part of the kernel which exhibit evident traces of an attack by vermin.
3.3.4 Grains having an abnormal colour – Grains whose natural colour has been modified by bad weather conditions, contact with the grain, heat, and excessive respiration. These grains may be dull, shrivelled, swollen, puffed, or bloated in appearance.
3.3.5 Sprouted grains – Grains exhibiting obvious signs of sprouting.
3.3.6 Frost damaged grains – Grains which are damaged by frost and may appear bleached or blistered and the seed coat may be peeling. Germs may appear dead or discoloured.
3.4 Broken kernels
Sorghum and pieces of sorghum which pass through a 1.8 mm round-hole sieve.
3.5 Other grains
Edible grains, whole or identifiable brokens, other than sorghum (i.e. legumes, pulses and other edible cereals).

4. Principle
The principle of the method is to separate all defects, defined under 3, from the normal basic grains by manual selection.
 

ICC DRAFT STANDARD No. 176

2. Scope
Applicable to whole grain sorghum.

3. Definitions
Sorghum grain endosperm texture is defined in terms of the proportion of corneous (horny/glassy/vitreous/steely) endosperm relative to floury (mealy/chalky/opaque) endosperm in the grain. Grains with a high proportion of corneous endosperm tend to be more resistant to breakage during decortication (dehulling) and milling than grains with a high proportion of floury endosperm.

Resistance of the grain to breakage is often referred to as grain strength or hardness.

Sorghum grain endosperm texture is of importance as “hard” grains tend to yield proportionally more clean (uncontaminated with bran) endosperm of large particle size during milling operations than “soft” grains.
“Hard” grains are also more resistant to insect and mould damage than “soft” grains.

4. Principle
Sorghum grains are cut into halves longitudinally.

One half is viewed with the naked eye and the relative proportion of corneous endosperm to floury endosperm is determined by reference to a standard.

On the basis of the relative proportion of corneous to floury endosperm, grains are classified into: corneous, intermediate and floury.

 

ICC DRAFT STANDARD No. 177

2. Scope
Applicable to whole grain sorghum.

3. Definitions
Certain varieties of sorghum contain proanthocyanidins (commonly referred to as tannins or more strictly-speaking condensed tannins) in the seed coat layer beneath the pericarp (commonly referred to as the testa layer) of the grain. These varieties are variously referred to as: tannin, high-tannin, brown, bird-proof, bird-resistant, or bitter sorghums.

Varieties of sorghum not containing tannins are various referred to as: non-tannin, low-tannin, condensed tannin-free, or sweet sorghums.

In this Standard the term “tannin sorghum” shall be used for those sorghums containing tannins and the term “non-tannin sorghum” used for those sorghums not containing tannins.

4. Principle
Sorghum grain is immersed in a sodium hypochlorite solution (bleach) containing alkali. The solution dissolves away the outer pericarp layer of sorghum grain, revealing the presence of a black pigmented testa layer in the case of tannin sorghums, or its absence in the case of non-tannin sorghums.

 

ICC RECOMMENDATION No. 201

2. Preparation of samples of various grain types
under construction!

ICC RECOMMENDATION No. 202

2. Scope
This procedure is applicable to protein and moisture determination in ground wheat and the products of wheat milling.

3. Principle
Analysis by NIR is dependent on calibration against a suitable standard method. Such calibration assumes an empirical model in which constituent concentration may be predicted by a linear combination of reflectance data at a number of wavelengths in an equation which includes a non-zero intercept term. Analysis of cereals by NIR is based on absorption of NIR energy at specific wavelengths, by peptide linkages between amino acids of protein molecules, by OH groups in starch molecules and by OH bonds in water molecules. Measurements at reference wavelengths and mathematical manipulation of the data are required for background correction.

4. Apparatus

4.1. Near infrared reflectance photometer or spectrometer: A number of firms manufacture various models of NIR instruments based upon principle 3. The individual instruments utilized must meet the performance specifications set out in 6.2., 6.3. and 6.4.

4.2. Grinding mill fitted with a screen of 0.5 to 1.0 mm mesh; e.g. KT 3100, KT 120, Kamas SKB 200, Udy Cyclone mill or Retsch Ultracentrifugal mill. (Other mills may also be suitable).

4.3. An electronic calculator with statistical functions or a small computer; the computing power required depends on the type of instrument and whether a new calibration is being produced or an existing one assessed.

ICC RECOMMENDATION No. 203

2. Scope
This ICC Standard provides practical numerical methods for the determination of repeatability and the reproducibility of the results of a standard test method.

3. Field of application
This ICC Standard is exclusively concerned with test methods the results of which are expressed quantitatively.

ICC RECOMMENDATION No. 204

2. Scope
The method is applicable to cereals and cereal foods and determines organohalogen, organophospate and synthetic pyrethroid residues in grain.

3. Principle
Ground cereal grain is extracted with acetone/methanol (1:1). Water is added beforehand in an amount that takes full account of the natural water content of the sample, so that during extraction the acetone : water ratio remains constant at 2:1. The extract is saturated with 3% sodium chloride solution and diluted with dichloromethane, resulting in separation of excess water. The evaporation residue of the organic phase is cleaned up by gel permeation chromatography on Bio Beads S-X3 (polystyrene gel) using a mixture of cyclohexane and ethyl acetate as eluant.  The residue-containing fraction is concentrated and analysed directly by gas chromatography using a phosphorus selective detector for organophosphorus and electron-capture detector for organohalogen pesticides. For the analysis of synthetic pyrethroids by electron capture detection, a supplemental clean-up on silica or alumina (neutral) sep-pak is always necessary.

4. Reagents
All reagents shall be suitable for the analysis of pesticide residues

4.1 Acetone.
4.2 Dichloromethane.
4.3 Ethyl acetate.
4.4 Cyclohexane.
4.5 GPC eluting mixture:  cyclohexane / ethyl acetate 1 - 1 v/v.
4.6 n-Hexane.
4.7 Pesticide standard solutions: 0.01-10 µg/ml (depending on detector sensitivity), in a suitable solvent
4.8 Glass wool, extracted exhaustively with acetone
4.9 Cotton-wool, extracted exhaustively with acetone
4.10 Bio Beads S-X32
4.11 Filter paper, 6 and 13,5 cm diameter, fast flow rate, extracted exhaustively with acetone

ICC RECOMMENDATION No. 206

Introduction

When performing microbiological examinations, it is especially important
a) that only the micro-organisms which are present in the sample are isolated or enumerated;
b) that the micro-organisms do not contaminate the environment.

In order to achieve this, it is necessary to pay attention to personal hygiene and to use working techniques that ensure, as far as possible, aseptic conditions.

Since in this International Standard, it is possible to give only a few examples of the precautions to be taken during micro-biological examinations, a thorough knowledge of microbiological examinations and of the micro-organisms involved is essential.

Ultimately, it is the analyst who should judge whether manipulations are safe and can be considered to be good laboratory practice.

Many manipulations may, for instance, unintentionally lead to cross-contamination and the analyst should always verify the accuracy of the results given by his technique.

In order to be able to perform examinations correctly, it is necessary to take certain precautions when constructing and equipping a laboratory. A number of such precautions are referred to in clause 4.

Certain precautions have to be taken not only for the sake of hygiene but also to ensure good reproducibility of results. It is not possible to specify all precautions to be taken in all circumstances, but the principal measures to be taken during the preparation, sterilization and storage of media and apparatus are described in clause 5.

If the guidance given in this International Standard is observed, this will also contribute to the protection of the health of personnel. For further information on this subject, reference should be made to the documentation listed in the bibliography, and in particular to references [1], [2] and [3].

1. Scope and field of application

This International Standard gives general instructions for carrying out microbiological examinations in accordance with specific standards.

The purpose of this International Standard is to help ensure the validity of examinations, to ensure that general techniques used for carrying out the examinations are the same in all laboratories and to contribute to the protection of the health of laboratory personnel by avoiding risks of infection.

2. Reference

• ISO 6887, Microbiology - General guidance for the preparation of dilutions for microbiological examination.

ICC RECOMMENDATION No. 207

2. Scope
The purpose of this method is the rough determination of the particle size and distribution of ground cereals and milling products with a moisture content of max. 16%.

3. Definition
The particle size is defined as the quantity of ground cereals remaining in sieves of specific mesh aperture after the sieving process, plus the screenings of the finest sieve used.

4. References

• ISO 3310/1: 1990, Test sieves - Technical requirements and testing - Part 1: Test sieves of metal wire cloth = DIN 4188
• ICC Standard No. 101/1, Sampling of Grain

ICC RAPID METHOD No. 301

2. Definition
Peroxidase (EC 1.11.1.7) is a heat stable enzyme that indicates inactivation of enzymes which might be involved in food deterioration.

3. Scope
The assay is recommended for cereal grains and products.

3. Principle
 necessary.

4. References

• ICC Standard No 101/1,Sampling of Grain
• ICC Standard No. 120,  Mechanical Sampling of Grain
• ICC Standard No. 110/1, Determination of Moisture Content of Cereals and Cereal Products (Practical Method)

ICC RAPID METHOD No. 302

2. Definition
Catalase (EC 1.11.1.6) is a heat sensitive enzyme that indicates minimum heat treatment. By action of catalase oxygen is released from hydrogen peroxide, the increase in oxygen is measured by an oxygen electrode.

3. Scope
The method was developed for wheat, rye, triticale, oats, barley and corn and is applicable for products out of the cereals. The advantage using an oxygen electrode is that no clear extracts are needed.

4. References

• ICC Standard No 101/1,Sampling of Grain
• ICC Standard No. 120,  Mechanical Sampling of Grain
• ICC Standard No. 110/1, Determination of Moisture Content of Cereals and Cereal Products (Practical Method)

ICC RAPID METHOD No. 303

3. Scope
The assay is recommended for cereal grains and products as well as all other materials containing this enzyme activity.

4. Sampling

• ICC Standard No 101/1,Sampling of Grain
• ICC Standard No. 120,  Mechanical Sampling of Grain
• ICC Standard No. 130,  Sampling of Milling Products (semolina, flours, agglomerated flours and by-products)

(see also   )