BS EN ISO 5983-2:2009 Animal feeding stuffs. Determination of nitrogen content and calculation of crude protein content. Block digestion and steam distillation method
BS EN ISO 5983-2 specifies a method for the determination of nitrogen content of animal feeding stuffs according to the Kjeldahl method, and a method for the calculation of the crude protein content. It is suitable for use as a semi-micro rapid routine method using block digestion, copper catalyst, and steam distillation into boric acid.
The method specified in BS EN ISO 5983-2 is applicable to the determination of greater than 0,5 % mass fraction Kjeldahl nitrogen in animal feeding stuffs, pet foods, and their raw materials. The method does not measure oxidized forms of nitrogen nor heterocyclic nitrogen compounds. The method does not distinguish between protein nitrogen and non-protein nitrogen.
Contents of BS EN ISO 5983-2:
Foreword
Scope
Normative references
Terms and definitions
Principle
Reagents
Apparatus
Sampling
Preparation of test sample
Procedure
General
Test portion
Determination
Blank test
Recovery tests
Calculation and expression of results
Calculation
Calculation of crude protein content
Expression of crude protein content results
Precision
Interlaboratory tests
Repeatability
Reproducibility
Test report
Results of interlaboratory tests
Results of a profiency test; comparison of the colorimetric and potentiometric endpoint etermination of the titration
Bibliography
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