ISO 2911-1976 rus PDF

Full title and description

St ISO 2911-1976 (rus) — Russian-language edition/translation of ISO 2911:1976, "Sweetened condensed milk — Determination of sucrose content — Polarimetric method". The document specifies a polarimetric laboratory method for measuring unaltered sucrose (saccharose) in sweetened condensed milk by treating a clarified filtrate and measuring optical rotation before and after acid-induced inversion.

Abstract

This standard describes a polarimetric procedure for determining the sucrose content of sweetened condensed milk of normal composition (prepared from whole, partially skimmed or skimmed milk and sucrose only). The method uses ammonia to equilibrate mutarotation of lactose, clarification with zinc acetate and potassium hexacyanoferrate(II), polarimetric measurement of optical rotation, acid inversion of sucrose (Clerget principle), and calculation of sucrose from the change in optical rotation.

General information

• Status: Withdrawn (superseded). Replaced by ISO 2911:2004 (also published as IDF 35:2004).
• Publication date: ISO original: December 1976 (ISO 2911:1976). Replacement edition published 25 November 2004 (ISO 2911:2004).
• Publisher: International Organization for Standardization (ISO). Russian-language edition: translated/distributed by national or commercial standards distributors (rus).
• ICS / categories: 67.100.10 — Milk and processed milk products.
• Edition / version: Original edition: 1976 (first edition). A later edition (edition 2) is ISO 2911:2004 which supersedes the 1976 edition.
• Number of pages: Original 1976 text: 3 pages (concise method specification). The 2004 edition is longer (≈7 pages).

Scope

Applies to determination of unaltered sucrose in sweetened condensed milk of normal composition (made from whole, partially skimmed or skimmed milk with added sucrose only). The procedure is intended for routine laboratory analysis and quality control; it is not applicable where sucrose has been altered or in products with unusual formulations without prior validation.

Key topics and requirements

• Principle: polarimetric determination of sucrose by measuring optical rotation before and after acid inversion (Clerget principle).
• Sample treatment: ammonium hydroxide to equilibrate lactose mutarotation, neutralization, clarification with zinc acetate and potassium hexacyanoferrate(II), and filtration.
• Reagents and apparatus: analytical-grade reagents, polarimeter, volumetric glassware (one-mark flasks, pipettes), specified concentrations for zinc acetate and potassium hexacyanoferrate(II).
• Calculation: sucrose content calculated from the change in optical rotation on inversion, expressed as mass fraction (percent).
• Applicability limits and validation notes: suitable for normal sweetened condensed milk; laboratories should follow good analytical practice and check method performance (precision, accuracy) for their matrix.

Typical use and users

Used by dairy-industry quality-control laboratories, product development and formulation teams, food-testing laboratories, regulators and inspection bodies, and academic researchers working on dairy product analysis. Typical applications are routine QC of incoming raw materials and finished sweetened condensed milk products, compliance testing, and method cross-checking.

Related standards

ISO 2911:2004 (IDF 35:2004) — current edition superseding ISO 2911:1976; ISO 1737 — determination of fat in evaporated and sweetened condensed milk (reference method); ISO 707 — guidance on sampling of milk and milk products; ISO 1042 and ISO 648 — laboratory glassware standards referenced for volumetric equipment. National identical/adopted versions (e.g., BS, NF, PN, BIS) exist for the 2004 edition.

Keywords

sweetened condensed milk, sucrose, saccharose, polarimetry, polarimetric method, optical rotation, Clerget inversion, zinc acetate, potassium hexacyanoferrate, dairy analysis, ISO 2911, IDF 35

FAQ

Q: What is this standard?

A: It is the Russian-language edition/translation of ISO 2911:1976 — an ISO method specifying a polarimetric procedure to determine sucrose content in sweetened condensed milk.

Q: What does it cover?

A: It covers sample preparation, reagents, polarimetric measurement before and after acid inversion of sucrose, and the calculation required to express sucrose as a percent of the product mass. The method is designed for typical sweetened condensed milk made with sucrose only.

Q: Who typically uses it?

A: Dairy industry QC laboratories, food-testing labs, regulatory agencies, product developers, and researchers performing compositional analysis of sweetened condensed milk.

Q: Is it current or superseded?

A: The 1976 edition is superseded. ISO 2911:1976 was replaced by ISO 2911:2004 (published 25 November 2004, also issued as IDF 35:2004). Laboratories should use the 2004 edition (or any later confirmed edition) for up-to-date requirements.

Q: Is it part of a series?

A: It is part of ISO/TC 34/SC 5 work on milk and milk products methods. The method is linked with other dairy standards (sampling, fat determination, laboratory glassware, etc.) and appears as ISO 2911 within ISO's numbering for dairy-product methods.

Q: What are the key keywords?

A: sweetened condensed milk; sucrose; polarimetry; optical rotation; Clerget inversion; dairy analysis; ISO 2911; IDF 35.