EN ISO 6885:2000

SLOVENSKI STANDARD
SIST EN ISO 6885:2001
01-februar-2001
5DVWOLQVNHLQåLYDOVNHPDãþREHLQROMD'RORþHYDQMHDQLVLGLQVNHJDãWHYLOD,62

Animal and vegetable fats and oils - Determination of anisidine value (ISO 6885:1998)
Tierische und pflanzliche Fette und Öle - Bestimmung der Anisidinzahl (ISO 6885:1998)
Corps gras d'origines animale et végétale - Détermination de l'indice d'anisidine (ISO
6885:1998)
Ta slovenski standard je istoveten z: EN ISO 6885:2000
ICS:
67.200.10 5DVWOLQVNHLQåLYDOVNH Animal and vegetable fats
PDãþREHLQROMD and oils
SIST EN ISO 6885:2001 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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INTERNATIONAL ISO
STANDARD 6885
Second edition
1998-07-01
Animal and vegetable fats and oils —
Determination of anisidine value
Corps gras d'origines animale et végétale — Détermination de l'indice
d'anisidine
A
Reference number
ISO 6885:1998(E)

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ISO 6885:1998(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide
federation of national standards bodies (ISO member bodies). The work of
preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which
a technical committee has been established has the right to be represented
on that committee. International organizations, governmental and non-
governmental, in liaison with ISO, also take part in the work. ISO
collaborates closely with the International Electrotechnical Commission
(IEC) on all matters of electrotechnical standardization.
Draft International Standards adopted by the technical committees are
circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting
a vote.
International Standard ISO 6885 was prepared by Technical Committee
ISO/TC 34, Agricultural food products, Subcommittee SC 11, Animal and
vegetable fats and oils.
This second edition of ISO 6885 cancels and replaces the first edition
(ISO 6885:1988), of which it constitutes a minor revision.
Annexes A and B of this International Standard are for information only.
©  ISO 1998
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced
or utilized in any form or by any means, electronic or mechanical, including photocopying and
microfilm, without permission in writing from the publisher.
International Organization for Standardization
Case postale 56 • CH-1211 Genève 20 • Switzerland
Internet iso@iso.ch
Printed in Switzerland
ii

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©
INTERNATIONAL STANDARD  ISO ISO 6885:1998(E)
Animal and vegetable fats and oils — Determination of
anisidine value
1 Scope
This International Standard specifies a method for the determination of the anisidine value, which is a measure of
the amount of aldehydes (principally 2-alkanals), in animal and vegetable fats and oils.
2 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions of this
International Standard. At the time of publication, the editions indicated were valid. All standards are subject to
revision, and parties to agreements based on this International Standard are encouraged to investigate the
possibility of applying the most recent editions of the standards listed below. Members of IEC and ISO maintain
registers of currently valid International Standards.
ISO 661:1989, Animal and vegetable fats and oils — Preparation of test sample.
ISO 3696:1987, Water for analytical laboratory use — Specification and test methods.
3 Definition
For the purposes of this International Standard, the following definition applies.
3.1
anisidine value
one hundred times the increase in absorbance, measured at a wavelength of 350 nm in a 10 mm cell, of a test
solution when reacted with p-anisidine under the test conditions specified in this International Standard
NOTE In practice the anisidine value is calculated on the basis of 1 g of test sample in 100 ml of solution.
4 Principle
Preparation of a test solution in 2,2,4-trimethylpentane (iso-octane). Reaction with an acetic acid solution of
p-anisidine and measurement of the increase in absorbance at 350 nm. Calculation of the anisidine value.
5 Reagents
Use only reagents of recognized analytical grade, and water complying with grade 3 of ISO 3696.
1

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©
ISO
ISO 6885:1998(E)
5.1  Sodium sulfate (Na SO ), anhydrous.
2 4
5.2  2,2,4-Trimethylpentane (iso-octane), having zero absorbance in the wavelength range 300 nm to 380 nm.
5.3  anhydrous cream-coloured crystals.
4-Methoxyaniline (p-anisidine),
WARNING — p-Anisidine is toxic and care should be taken to avoid contact with the skin.
Store the p-anisidine in a dark bottle at 0 °C to 4 °C in the dark.
No discoloration (grey or pink) shall be observed. If this is present, purify the p-anisidine as follows.
Dissolve 4 g of p-anisidine in 100 ml of water at 75 °C. Add 0,5 g of sodium sulfite (Na SO ) and 2 g of charcoal. Stir
2 3
for 5 min and filter through a medium retention filter paper to give a clear solution. Cool the filtrate to 0 °C and leave
at this temperature for not less than 4 h. Filter off the crystals, preferably under vacuum, and wash with a small
volume of water at about 0 °C. Dry in a vacuum desiccator containing an efficient desiccant.
5.4  Glacial acetic acid, of water content not greater than 0,1 % (m/m).
5.5  Anisidine reagent
On the day of use prepare the minimum quantity of reagent required for the analysis, in view of its toxicity and
limited life. Prepare, for example, 50 ml of reagent as follows.
Dissolve 0,125 g of the p-anisidine (5.3) in the glacial acetic acid (5.4) in a 50 ml volumetric flask and dilute to the
mark with the same solvent, avoiding exposure to strong light.
Check the absorbance before use and discard the reagent if this rises above 0,2. In any case, discard any reagent
left over on the day of use.
6 Apparatus
Usual laboratory apparatus and, in particular, the following.
6.1  Spectrometer, double- or single-beam, suitable for use at a wavelength of 350 nm, with cells of optical path
length 10 mm.
When a double-beam spectrometer is used, it is recommended that a pair of matched 10 mm cells be used.
6.2  Volumetric flasks, of 25 ml capacity.
6.3  Test tubes, of 10 ml capacity, fitted with ground glass stoppers.
6.4  Pipettes, of 1 ml and 5 ml capac
...