Kjeldahl method, for determination

The performance of the combustion method compares favorably with that of the mercury catalyst Kjeldahl method for determination of crude protein in feeds. Standard deviations by the combustion method covered the full range of possibilities compared to the Kjeldahl method values were either equivalent, better than, or not as good as for the Kjeldahl method. For the 0.5-mm pairs, values ranged from 0.09% to 0.58% protein for the Kjeldahl method and from 0.14% to 0.33% protein for the combustion method, and (SR) values ranged from 0.23% to 0.86% protein (Kjeldahl) and from 0.30% to 0.61% protein (combustion). 

Kjeldahl method for determination of nitrogen in organic compounds The... 

Daun, J.K. and DeClercq, D.R. 1994. Comparison of combustion and Kjeldahl methods for determination of nitrogen in oilseeds. JAOCS, 71(10), 1069-1072. 

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