ISO 1871-2009 PDF

Full title and description

Food and feed products — General guidelines for the determination of nitrogen by the Kjeldahl method (ISO 1871:2009). This International Standard gives general guidance on the application of the Kjeldahl principle for total nitrogen determination in foods and animal feeds; it does not account for nitrogen present as nitrates or nitrites.

Abstract

ISO 1871:2009 provides a concise, general set of guidelines describing the Kjeldahl procedure’s scope, principle, sample considerations, digestion and distillation options, and calculation of results for food and feed matrices where the Kjeldahl technique is appropriate. The document clarifies limitations of the method (not covering nitrate/nitrite nitrogen) and references more specific product standards where required.

General information

• Status: Published (International Standard, edition confirmed in ISO review process).
• Publication date: 2009 (Edition 2 — issued August/September 2009).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 67.050 — General methods of tests and analysis for food products.
• Edition / version: Edition 2 (2009).
• Number of pages: ISO official edition: 7 pages (concise format); national adoptions (for example BSI) may show longer pagination (e.g., 16 pages) due to national front matter and forewords.

Scope

Applies to food and feed products containing nitrogenous compounds that can be determined directly by the Kjeldahl method. It sets out general principles, precautions and reporting requirements intended to support consistent application of Kjeldahl-based nitrogen determinations, and points users to product-specific ISO/other methods where detailed procedures and performance criteria are required. The standard excludes determination of nitrogen originating from nitrates and nitrites.

Key topics and requirements

• Principle of the Kjeldahl method: digestion (mineralization), neutralization, distillation and titration or equivalent detection of liberated ammonia.
• Scope and limitations — specifically excludes nitrate/nitrite nitrogen and highlights matrices where Kjeldahl is suitable.
• Sample preparation considerations and representative sampling guidance (general level).
• General recommendations for reagents, catalysts, digestion aids and safety precautions.
• Result calculation and reporting (conversion of nitrogen to crude protein where applicable) and statement of method limitations and uncertainty considerations.
• Cross-references to product-specific Kjeldahl reference or routine methods (e.g., milk, meat, cereals, animal feed standards).

Typical use and users

Used by food and feed testing laboratories, quality-control units in food/feed manufacturing, standards bodies, regulatory laboratories and method validation teams. It is intended as a general reference for experienced analysts and laboratory managers to harmonize application of Kjeldahl-based nitrogen determinations and to point to more detailed, matrix-specific methods where needed.

Related standards

ISO 1871:2009 is a general guideline and is used in conjunction with product-specific or matrix-specific standards and official methods. Related documents include earlier ISO 1871:1975 (replaced), and many ISO product standards that specify Kjeldahl procedures for particular materials (for example ISO 937 for meat, ISO 5983 for animal feeding stuffs, ISO 8968 for milk and milk products, ISO 20483 for cereals and pulses, plus various AOAC/USP/EP methods). Users should consult the relevant product standard for detailed method steps and performance criteria.

Keywords

Kjeldahl, nitrogen determination, crude protein, food analysis, feed analysis, digestion, distillation, titration, ISO 1871:2009, analytical guideline, 67.050.

FAQ

Q: What is this standard?

A: ISO 1871:2009 is an ISO International Standard that provides general guidelines for determining nitrogen in food and feed by the Kjeldahl method.

Q: What does it cover?

A: It covers the general principle, scope, limitations (not including nitrate/nitrite nitrogen), sample considerations, safety and calculation/reporting guidance for Kjeldahl nitrogen determinations and references to product-specific methods.

Q: Who typically uses it?

A: Accredited testing and QC laboratories, regulatory bodies, standardization committees and manufacturers’ laboratories that perform or oversee Kjeldahl nitrogen analyses in foods and feeds.

Q: Is it current or superseded?

A: ISO 1871:2009 (Edition 2) is the current ISO edition published in 2009; the earlier ISO 1871:1975 was withdrawn and replaced. The edition has been subject to ISO periodic review and is listed as confirmed in ISO’s review cycle. Users should check with their national body or ISO for the latest status before use.

Q: Is it part of a series?

A: It is a general guidance document within the family of ISO food/feed analytical standards (ICS 67) and is commonly used alongside many matrix-specific ISO standards (e.g., ISO 937, ISO 5983, ISO 8968, ISO 20483) and recognized official methods (AOAC, pharmacopeial monographs).

Q: What are the key keywords?

A: Kjeldahl, nitrogen, crude protein, food analysis, feed analysis, digestion, distillation, titration, ISO 1871, ICS 67.050.