10.1 Determination of Total Nitrogen
According to AOAC 984.13.
10.2 Determination of Amino Nitrogen
According to AOAC 920.154 B (Sorensen Method) on the following conditions:
- Preparation of test samples
Weigh 2 g of sample into a 250 ml beaker and mix the sample with 100 ml of cold (15°C) NH3-free H2O and then stir the mixture for 60 min. Next, decant the mixture through a quantitative filter and collect the filtrate in a 100 ml volumetric flask.
- Endpoint
A pH meter shall be used to determine the endpoint instead of optical verification of colors.
10.3 Determination of Moisture
According to AOAC 934.01 at a drying temperature of 70ºC or lower.