Methods Type: Generic Methods
Key data
Analyte: Crude Protein (Dumas Combustion Principle)
Matrix: Grain and Grain Products for Food and Feed
Scope: The measurement of the total nitrogen content in grain and grain products and, by calculation, protein content.
Principle:
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.
Nitrogen gas is measured with a thermal conductivity detector.
Total nitrogen is calculated from the detector response. The detector is calibrated with a known nitrogen standard.
Automatic combustion analysers rely on a carrier gas, such as helium or carbon dioxide.
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.
Purchase this ICC Standard Method now and download it immediately!
