DIN EN ISO 16634-2
Food products - Determination of the total nitrogen content by combustion according to the Dumas principle and calculation of the crude protein content - Part 2: Cereals, pulses and milled cereal products (ISO 16634-2:2016); German version EN ISO 16634-2:2016
Lebensmittelerzeugnisse - Bestimmung des Gehaltes an Gesamtstickstoff mit dem Verbrennungsverfahren nach Dumas und Berechnung des Gehaltes an Rohprotein - Teil 2: Getreide, Hülsenfrüchte und gemahlene Getreideerzeugnisse (ISO 16634-2:2016); Deutsche Fassung EN ISO 16634-2:2016
Overview
This part of ISO 16634 specifies a method for the determination of the total nitrogen content and the calculation of the crude protein content of cereals, pulses and milled cereal products. The procedure should be considered from the point of view of quality determination. This method, like the Kjeldahl method, does not distinguish between protein nitrogen and non-protein nitrogen. For the calculation of the protein content, various conversion factors are used. Samples are converted into gases by heating in a combustion tube. Interfering components are removed from the resulting gas mixture. The nitrogen compounds in the gas mixture, or a representative part of them, are converted to molecular nitrogen which is quantitatively determined by a thermal-conductivity detector. The nitrogen content is calculated by a microprocessor. The committee responsible for this standard is NA 057-05-06 AA "Getreide und Getreideerzeugnisse" ("Cereals and cereal products") at DIN.
Document: references other documents
Responsible national committee
NA 057-05-06 AA - Cereals and cereal products
Responsible european committee
CEN/TC 338 - Cereal and cereal products
