ISO 12966-3-2016 PDF

Full title and description

Animal and vegetable fats and oils — Gas chromatography of fatty acid methyl esters — Part 3: Preparation of methyl esters using trimethylsulfonium hydroxide (TMSH). This International Standard specifies a rapid base‑catalysed transesterification method using TMSH to prepare fatty acid methyl esters (FAMEs) for gas‑liquid chromatographic analysis of fats and oils.

Abstract

ISO 12966-3:2016 describes a rapid TMSH‑based transmethylation procedure applicable to the preparation of methyl esters of fats and oils (excluding milk and milk products) for GLC analysis. The method causes only minor isomerization of unsaturated fatty acids (not recommended for conjugated linoleic acid (CLA)), esterifies approximately 70–80 % of free fatty acids, and may produce side reactions for certain conjugated cyclopropyl/cyclopropenyl fatty acids that do not interfere with typical determinations.

General information

• Status: Published (International Standard, confirmed on review).
• Publication date: May 2016 (Edition 2, 2016-05).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 67.200.10 (Animal and vegetable fats and oils).
• Edition / version: Edition 2 (2016).
• Number of pages: 4 (ISO bibliographic entry). Note: national implementations/publications occasionally list longer printable page counts due to formatting and national forewords.

Scope

This part of ISO 12966 specifies a rapid base‑catalysed transesterification (TMSH) for preparing fatty acid methyl esters from animal and vegetable fats and oils for gas‑liquid chromatographic (GLC) analysis. Milk and milk products (or fat coming from them) are excluded. The procedure is intended exclusively for preparing methyl esters for chromatographic analysis and is not recommended when conjugated linoleic acid (CLA) quantification is required due to minor isomerization.

Key topics and requirements

• Rapid base‑catalysed transmethylation using trimethylsulfonium hydroxide (TMSH) to produce FAMEs for GLC analysis.
• Applicability to a wide range of animal and vegetable fats and oils, excluding milk and milk products.
• Notes on isomerization: only minor isomerization of unsaturated fatty acids occurs; not recommended for CLA analysis.
• Typical conversion: about 70–80 % esterification of free fatty acids under the procedure.
• Caveat: possible side reactions with conjugated cyclopropyl and cyclopropenyl fatty acids that generally do not interfere with FAME determination.
• Intended output: chromatographically suitable FAMEs for subsequent analysis by the methods described in the ISO 12966 series (e.g., capillary GC determination in Part 4).

Typical use and users

Laboratories performing lipid profiling and fatty acid composition analysis in the food, feed and oilseed industries; quality control and R&D labs in edible oil refining and food production; contract analytical laboratories; research groups studying lipid composition; and national or international testing bodies implementing standardized FAME preparation for GC analysis. The standard is developed under ISO/TC 34/SC 11 (fats and oils).

Related standards

ISO 12966 is a multipart series on gas chromatography of fatty acid methyl esters. Key related parts include: - ISO 12966-1:2014 — Guidelines on modern gas chromatography of FAMEs (overview and guidance). - ISO 12966-2:2017 — Preparation of methyl esters of fatty acids (additional methylation methods). - ISO 12966-4:2015 — Determination by capillary gas chromatography (conditions for GC analysis of FAMEs).

Keywords

fats and oils; fatty acid methyl esters (FAME); trimethylsulfonium hydroxide (TMSH); transesterification; gas chromatography (GLC/GC); lipid analysis; conjugated linoleic acid (CLA); ISO 12966.

FAQ

Q: What is this standard?

A: ISO 12966-3:2016 is the International Standard that specifies a rapid TMSH‑based method to prepare fatty acid methyl esters from animal and vegetable fats and oils for gas chromatographic analysis.

Q: What does it cover?

A: It covers a base‑catalysed transesterification procedure using trimethylsulfonium hydroxide (TMSH) to produce chromatographically suitable FAMEs, notes limitations (excludes milk/milk products; minor isomerization; not recommended for CLA), and provides requirements for sample preparation prior to GC analysis.

Q: Who typically uses it?

A: Analytical chemists in food/oil/fat testing laboratories, quality control and research groups in the edible oil and food industries, contract testing labs, and regulatory testing bodies that require standardized preparation of FAMEs for GC.

Q: Is it current or superseded?

A: ISO 12966-3:2016 (Edition 2) is published and was reviewed/confirmed in ISO's systematic review process (confirmed in 2021), so it remains the current edition as listed by ISO. The 2016 edition replaced the 2009 version.

Q: Is it part of a series?

A: Yes — ISO 12966 is a multipart series on gas chromatography of fatty acid methyl esters; other parts include ISO 12966-1 (guidance), ISO 12966-2 (additional methylation methods), and ISO 12966-4 (capillary GC determination).

Q: What are the key keywords?

A: FAME, TMSH, transesterification, gas chromatography, fats and oils, lipid analysis, CLA (conjugated linoleic acid), ISO 12966.