Collaborative Comparison of Dumas and Kjeldahl Methods for Nitrogen in Feeds

Abstract

Abstract A collaborative study to compare the Dumas and Kjeldahl methods for nitrogen determination in agricultural feed materials has been completed. The Dumas method used the Nitrogen Analyzer II, Coleman Model 29A. The mean values of the six feed materials studied showed good agreement between the two methods. Standard deviation ranged from ±0.18 to ±0.39 for the Dumas method and from ±0.06 to ±0.40 for the Kjeldahl method. For two organic standard materials studied, the Dumas method gave better accuracy. Standard deviation for both methods on these organic standards was poorer than for the feed materials, and further study is recommended.