AOAC Official Method 935.58 Nitrogen (Total) in Food Dressings Improved Kjeldahl Method

Improved Kjeldahl Method
First Action 1935
Final Action

Accurately weigh ca 15 g test portion into 500 mL Kjeldahl flask and place on steam bath until egg is thoroughly cooked and oil separates
readily. Cool, and add ca 50 mL petroleum ether; mix, and decant petroleum ether through small filter. Repeat petroleum ether treatment twice, rinsing out as much oil as possible. Wash filter with petroleum ether and add filter paper to sample in flask. Determine N, using 50 mL H2SO4 (more, if necessary) for digestion, as in 920.165« (see 43.1.06).