ISO 8968-3|IDF 20-3:2004 specifies a method for the determination of the nitrogen content of liquid, whole or skimmed milk. It concerns a semi-micro rapid routine method following the block-digestion principle.
Tämän julkaisun valmistelusta Suomessa vastaa SFS Suomen Standardit, puh. 09 149 9331.
Sisällysluettelo
Foreword
Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Reagents
5.1 Kjeldahl catalyst tablets
5.4 Antifoaming agent
5.6 Boric acid solutions
5.7 Indicator solutions
6 Apparatus
7 Sampling
8 Preparation of test sample
9 Procedure
9.1 Test portion and pretreatment
9.2 Determination
9.3 Blank test
9.4 Recovery tests
10 Calculation and expression of results
10.1 Calculation of nitrogen content
10.2 Calculation of crude protein content
11 Precision
11.1 Interlaboratory test
11.2 Repeatability
11.3 Reproducibility
12 Test report
Annex A Results of interlaboratory test (informative)
Annex B Modified procedure for analysis of other milk products (informative)