# ISO 937:1978 — Withdrawn and superseded ISO standards

For ISO 937:1978, item title is Meat and meat products — Determination of nitrogen content (Reference method); status code is 9599; successor is ISO 937:2023; withdrawn / published date is 1978-12-01, recorded from its source on 2026-08-05.

- **Identifier:** ISO 937:1978 _(verified: appears in the quote below)_
- **Item title:** Meat and meat products — Determination of nitrogen content (Reference method) _(verified: appears in the quote below)_
- **Status code:** 9599 _(verified: appears in the quote below)_
- **Successor:** ISO 937:2023
- **Withdrawn / published date:** 1978-12-01 _(verified: appears in the quote below)_

## What the source says

> 5356,IS,,ISO 937:1978,Meat and meat products — Determination of nitrogen content (Reference method),Viandes et produits à base de viande — Détermination de la teneur en azote (Méthode de référence),1978-12-01,1,['67.120.10'],ISO/TC 34/SC 6,9599,,[82663],"['en','fr']",3,"<p>The method consists in digesting of a test portion with concentrated sulphuric acid, using copper(II) sulphate as a catalyst, to convert organic nitrogen to ammonia ions. Then alkalisation, distillation of the liberated ammonia into an excess of boric acid solution, titration with hydrochloric acid to determine the ammonia bound by the boric acid, and calculation of nitrogen content of the sample from the amount of ammonia

## Source

- https://isopublicstorageprod.blob.core.windows.net/opendata/_latest/iso_deliverables_metadata/csv/iso_deliverables_metadata.csv

Last verified: 2026-08-05. Review by: 2027-02-01.
Part of [Withdrawn and superseded ISO standards](https://referencesource.org/iso-standard-supersessions/).