ISO 6732-2010 PDF

Full title and description

St ISO 6732-2010 — Milk and milk products — Determination of iron content — Spectrometric method (Reference method). Joint ISO/IDF reference method (ISO 6732 | IDF 103:2010) that specifies a spectrometric procedure for determining total iron in milk and a wide range of milk products.

Abstract

ISO 6732:2010 specifies a reference spectrometric method for the quantification of iron in milk and milk products. The procedure covers sample preparation (including acid digestion), chemical conversion and complexation of iron to a spectrophotometrically measurable form, extraction, calibration with iron standards and measurement of optical density. The method is intended as a reference procedure for routine and confirmatory determinations in dairy analysis laboratories.

General information

• Status: Published (active edition; joint ISO/IDF publication)
• Publication date: 2010-06 (Edition 2, 2010)
• Publisher: International Organization for Standardization (ISO), published jointly as IDF 103 by the International Dairy Federation
• ICS / categories: 67.100.01 (Milk and milk products in general)
• Edition / version: Edition 2 (2010)
• Number of pages: 12

Scope

The standard applies to the determination of iron content in a broad range of milk and milk-derived products, including fresh milk (whole and skimmed), whey and buttermilk, natural and skimmed yogurts, evaporated and sweetened condensed milk, dried milk powders (whole and skimmed), dried whey and buttermilk powders, cream, butter and anhydrous butterfat (butteroil, ghee), ice-cream, cheeses (various ages and processed cheese), and caseins/caseinates and similar coprecipitates. It provides the reference spectrometric procedure appropriate for these matrices.

Key topics and requirements

• Sample preparation and homogenization appropriate to the product type (grinding, sieving, centrifugation where required).
• Acid digestion of organic matrix (typically using nitric acid with appropriate oxidants) to convert iron into a measurable form and remove organic interferences.
• Chemical reduction of iron to the ferrous state and formation of a coloured complex (bathophenanthroline-type reagent) suitable for spectrometric measurement.
• Liquid–liquid extraction of the iron complex (isoamyl alcohol or similar) to isolate the coloured complex from aqueous interferences.
• Photometric/spectrometric measurement of the extract at the method wavelength (the coloured Fe(II) complex is measured in the visible region — commonly reported around 533 nm) and comparison with calibrated iron standards.
• Calibration, preparation of iron standard solutions, and use of certified reference materials where available.
• Strict contamination control (clean glassware, acid-washed equipment, avoidance of rust/iron contamination) and laboratory-quality good-practice requirements.
• Recommended apparatus (analytical balance, centrifuge, digestion equipment, glassware free of iron, spectrophotometer) and procedural quality controls.

Typical use and users

Reference and accredited food testing laboratories, dairy industry quality-control and R&D labs, national and regional regulatory/inspection bodies, university and research laboratories working on dairy composition and food safety. The method is used for routine monitoring, regulatory compliance testing, method validation and inter-laboratory comparisons where a reference spectrometric procedure for iron is required.

Related standards

ISO 6732:2010 replaces ISO 6732:1985. It is part of the suite of ISO/IDF reference methods for dairy analysis; related standards include other ISO/IDF dairy reference methods (for example ISO 6731:2010 on total solids and ISO 6734:2010 for sweetened condensed milk total solids) and alternative methods for iron determination such as atomic absorption (AAS) or ICP-based methods published by AOAC/NMKL and other bodies. The text is published jointly as IDF 103:2010.

Keywords

iron, Fe, milk, milk products, spectrometric method, bathophenanthroline, extraction, reference method, ISO 6732, IDF 103, digestion, dairy analysis

FAQ

Q: What is this standard?

A: ISO 6732:2010 (also published as IDF 103:2010) is the ISO reference method for determining iron content in milk and milk products using a spectrometric (colourimetric) procedure.

Q: What does it cover?

A: It covers sample preparation, acid digestion, reduction and complexation of iron, extraction of the coloured Fe(II) complex and spectrometric measurement against calibrated standards — applicable to a wide range of milk products listed in the scope.

Q: Who typically uses it?

A: Accredited food and dairy testing laboratories, dairy industry QC/R&D teams, regulatory laboratories and researchers who need a validated reference procedure for iron determination in dairy matrices.

Q: Is it current or superseded?

A: ISO 6732:2010 is the second edition published in 2010 and replaced the 1985 edition. It is the current ISO/IDF reference edition (published 2010) and remains the active reference method unless amended or replaced by a later edition.

Q: Is it part of a series?

A: Yes — it is part of the ISO/IDF collection of dairy reference methods (ISO/TC 34/SC 5). It is published jointly with the International Dairy Federation as IDF 103:2010 and is related to other ISO dairy-method standards.

Q: What are the key keywords?

A: iron, Fe, milk, dairy, spectrometric, bathophenanthroline, reference method, digestion, ISO 6732, IDF 103.