ISO 8195:1987

Caseins and caseinates — Determination of nitrate and nitrite contents — Method by cadmium reduction and spectrometry

The principle of determination consists in dispersing the casein or caseinate in warm water, precipitating the fat and proteins, filtering and reducing the nitrate to nitrite in a portion of the filtrate by means of copperized cadmium. A figure shows the apparatus for nitrate reduction.