ISO 6735-1985 PDF

Full title and description

ISO 6735:1985 — Dried milk — Assessment of heat class — Heat‑number reference method. Specifies a laboratory reference method for determining the heat‑number used to assess the heat‑treatment class of spray‑dried whole, partly skimmed and skimmed milk (also applicable to instant dried milks).

Abstract

This International Standard defines a heat‑number reference method and a proposed heat‑classification scheme (four classes: low, medium, medium‑high, high) for assessing the heat‑treatment class of dried milk produced by spray drying; Annex A describes the Kjeldahl method and Annex B provides the proposed classification scheme.

General information

• Status: Withdrawn / Annulled (withdrawal stage recorded by ISO).
• Publication date: November 1985 (Edition 1, 1985-11).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 67.100.10 (Milk and milk products).
• Edition / version: Edition 1 (1985).
• Number of pages: 8 pages.

Scope

Specifies a reference laboratory procedure to determine the heat number of spray‑dried whole, partly skimmed and skimmed milk (as defined by Codex A‑5), and uses the heat number to assign a heat‑treatment class. The method is also stated as applicable to instant dried milks. The standard is limited to assessment by the heat‑number technique and includes supporting annexes for analytical details.

Key topics and requirements

• Definition and determination of the heat number for dried milk (reference laboratory procedure).
• Heat‑classification scheme proposing four heat classes (low, medium, medium‑high, high).
• Procedural detail and analytical support including a Kjeldahl method in Annex A.
• Applicability to spray‑dried and instant dried milk types; sampling and test conditions suitable for laboratory use.

Typical use and users

Used historically by dairy testing laboratories, quality assurance teams in milk‑powder manufacturing, food safety and regulatory bodies, and researchers comparing thermal processing effects on powdered milk. Although withdrawn, the method may still be referenced in older laboratory protocols and national adoptions.

Related standards

Related ISO standards from the ISO/TC 34 (Milk and milk products) portfolio include other analytical methods for milk and milk products (examples: ISO 6740:1985, ISO 6785:1985 and other dairy test methods); national adoptions/revisions (for example LST ISO 6735:1997) exist for some countries. Users should consult current ISO/TC 34 outputs for up‑to‑date replacements.

Keywords

dried milk; milk powder; heat number; heat class; thermal treatment assessment; spray‑dried milk; Kjeldahl; ISO 6735; milk testing; ISO/TC 34/SC 5.

FAQ

Q: What is this standard?

A: ISO 6735:1985 is an ISO International Standard titled "Dried milk — Assessment of heat class — Heat‑number reference method" that defines a laboratory reference method for determining a heat number and assigning a heat‑treatment class to spray‑dried and instant dried milks.

Q: What does it cover?

A: It covers the reference analytical procedure to determine the heat number, a proposed four‑class heat‑classification scheme, and includes technical annexes (Kjeldahl method and the classification scheme). It is limited to assessment by the heat‑number technique.

Q: Who typically uses it?

A: Intended users were dairy testing laboratories, quality control personnel in milk‑powder production, regulators and researchers. National standards bodies have also adopted or referenced the method historically.

Q: Is it current or superseded?

A: ISO 6735:1985 has been withdrawn (stage: withdrawal of the International Standard). The ISO catalogue shows it as withdrawn; no single direct replacement is indicated on the ISO record for this number, so users should check ISO/TC 34/SC 5 current publications for updated methods.

Q: Is it part of a series?

A: It is part of the body of ISO standards produced under ISO/TC 34/SC 5 (Milk and milk products) covering analytical methods and compositional/contaminant testing for milk and dairy products; related and neighboring standards address nitrate/nitrite determination, salmonella detection, total solids, and other milk‑testing methods.

Q: What are the key keywords?

A: Dried milk, heat number, heat class, spray‑dried, milk powder, Kjeldahl, thermal treatment, milk testing, ISO 6735.