ISO 16634-1-2008 PDF

Full title and description

Food products — Determination of the total nitrogen content by combustion according to the Dumas principle and calculation of the crude protein content — Part 1: Oilseeds and animal feeding stuffs (ISO 16634-1:2008). This part specifies a Dumas combustion method for measuring total nitrogen and calculating crude protein in oilseeds and animal feeding stuffs.

Abstract

ISO 16634-1:2008 defines a procedure based on combustion (Dumas principle) to determine total nitrogen in oilseeds and animal feeding stuffs and describes how to calculate crude protein using appropriate conversion factors. The method does not distinguish protein-N from non‑protein-N and is not applicable to milk and milk products.

General information

• Status: Published (International Standard). The document was reviewed/confirmed and has been placed under periodic review; a revision / DIS has been prepared.
• Publication date: 2008-11 (1st edition, 2008).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 65.120; 67.050; 67.200.20.
• Edition / version: Edition 1 (2008).
• Number of pages: 30 (as published).

Scope

This part of ISO 16634 specifies a method to determine total nitrogen in oilseeds and animal feeding stuffs by high‑temperature combustion (Dumas principle) and the subsequent calculation of crude protein content using established conversion factors. It excludes milk and milk products and, like Kjeldahl-based methods, does not separate protein and non‑protein nitrogen. The standard covers required apparatus, reagents, sample preparation, calibration, calculation and expression of results, and performance criteria relevant to the test method.

Key topics and requirements

• Principle: total nitrogen determination by combustion (Dumas) and detection of released nitrogen (e.g., thermal conductivity or equivalent detectors).
• Specified apparatus and materials for combustion analysis and for sample handling.
• Sample preparation and representative sub‑sampling procedures for oilseeds and feedstuffs.
• Calibration, use of suitable reference materials and blanks, and routine performance checks.
• Calculation procedures to convert measured total nitrogen to crude protein using stated conversion factors.
• Reporting requirements, expression of results and interpretation limits (including method applicability and exclusions).
• Performance characteristics, quality control and precision/repeatability expectations for laboratory use.

Typical use and users

Laboratories performing compositional analysis of oilseeds and animal feeds, feed manufacturers, quality control and assurance teams in agrifood businesses, regulatory and inspection bodies, and instrument manufacturers supplying combustion analyzers. The method is used where rapid and automated nitrogen/protein testing is required as an alternative to Kjeldahl procedures.

Related standards

ISO 16634 is a multi‑part series. Part 2 addresses cereals, pulses and milled cereal products (ISO 16634-2:2016). Earlier technical specifications and national/adopted versions (e.g., EN/BS/ISO adoptions) exist; revisions and DIS documents for the series are in development.

Keywords

Dumas method; combustion analysis; total nitrogen; crude protein; oilseeds; animal feeding stuffs; feed analysis; sample preparation; calibration; ISO 16634.

FAQ

Q: What is this standard?

A: ISO 16634-1:2008 is an international standard that specifies a combustion (Dumas) method for determining total nitrogen and calculating crude protein in oilseeds and animal feeding stuffs.

Q: What does it cover?

A: It covers the principle of the method, required apparatus and reagents, sample preparation, calibration, calculation of results (conversion to crude protein), and reporting. It is not applicable to milk and milk products and does not distinguish protein from non‑protein nitrogen.

Q: Who typically uses it?

A: Analytical laboratories, feed manufacturers and quality assurance teams, regulatory agencies, and instrument vendors that perform or support nitrogen/protein analysis for oilseeds and animal feeds.

Q: Is it current or superseded?

A: ISO 16634-1:2008 remains a published International Standard; it has been subject to periodic review. A draft revision (ISO/DIS 16634-1) has been prepared to replace the 2008 edition, so users should check for the latest published revision before applying the method.

Q: Is it part of a series?

A: Yes — ISO 16634 is a multi‑part series dealing with Dumas combustion methods for different food/feed categories; Part 2 (ISO 16634-2:2016) covers cereals, pulses and milled cereal products.

Q: What are the key keywords?

A: Dumas, combustion analysis, total nitrogen, crude protein, oilseeds, animal feeding stuffs, feed analysis, ISO 16634.