Starches and derived products -- Determination of nitrogen content by the Kjeldahl method -- Spectrophotometric method
This standard was last reviewed and confirmed* in 2013.
Destruction of organic matter by sulphuric acid in the presence of a compound catalyst (see ISO 1871), alkalization of the reaction products, destillation of the liberated ammonia and collection in a sulphuric acid solution, followed by measuring of the ammonium salt formed after the addition of Nessler reagent. The method is provided for contents less than 0,025 % (m/m). For greater contents, see ISO 3188.
Document published on: 1978-06 Edition: 1 (Monolingual) ICS: 67.180.20 Status: Published Stage: 90.93 (2013-04-04) TC/SC: ISO/TC 93 Number of Pages: 3
This standard has not been revised
No corrigenda or amendments available