Reference number
ISO 3188:1978
ISO 3188:1978
© ISO 2024
International Standard
ISO 3188:1978
Starches and derived products — Determination of nitrogen content by the Kjeldahl method — Titrimetric method
Edition 1
1978-08
1978-08
ISO 3188:1978
8379
Published
(Edition 1, 1978)
This publication was last reviewed and confirmed in 2019.
Therefore this version remains current.
Abstract
The found value only includes free amino acids, compounds producing amino acids on hydrolysis and ammonium compounds. The principle consists in destruction of organic matter by sulphuric acid in the presence of a compound catalyst (see ISO 1871), alkalization of the reaction products, distillation of the liberated ammonia and collection in a boric acid solution, followed by titration with a standard volumetric sulphuric acid solution. The method applies to contents greater than 0,01 % (m/m). For products with contents less than 0,025 % (m/m), see ISO 5378.
