ISO INTERNATIONAL STANDARD 6800 Second edition 1997-12-15 Animal and vegetable fats and oils - Determination of the composition of fatty acids in the 2-position of the triglyceride molecules Corps gras d'origines animale et végétale Détermination de la composition des acides gras en position 2 dans les triglycerides Tso Referencenumber ISO 6800:1997(E) No r py IHS under ted without license from IHS Not for Resale ISO 6800:1997(E) Foreword IsO (the International Organization for Standardization) is a worldwide federationofnationalstandardsbodies(lsOmemberbodies).Theworkof 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 (lEC)onallmattersofelectrotechnicalstandardization. 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 6800 was prepared by Technical Committee ISO/TC 34, Agricultural food products, Subcommittee SC 11, Animal and vegetable fats and oils. This second edition cancels and replaces the first edition (IsO 6800:1985), which has been technically revised. ?ISO1997 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced microfilm, without permission in writing from the publisher. InternationalOrganizationforStandardization Case postale 56· CH-1211 Geneve 20 · Switzerland Internet [email protected] X.400 C=ch; a=400net; p=iso; 0=isocs; S=central Printed in Switzerland ense from IHS Not for Resale ISO 6800:1997(E) INTERNATIONAL STANDARD @ISO Animal and vegetable fats and oils Determination of the composition of fatty acids in the 2-position of the triglyceride molecules 1 Scope This International Standard specifies a method for the determination of the composition of fatty acids which are esterified in the 2-position (B or internal position) of the triglyceride molecules in animal and vegetable fats and oils. Because of the nature of pancreatic lipase action, the method is applicable only to fats and oils with a melting point below 45 C. The method is not unreservedly applicable to all fats and oils, particularly those containing substantial amounts of fatty acids with 12 or fewer carbon atoms (e.g. copra oil, palm kernel oil, butyric butter fats); fatty acids with 20 and more carbon atoms and of a high degree of unsaturation (more than four double bonds) (e.g. fish oil and marine animal oil); -fatty acids which have secondary groups containing oxygen. NOTE - Fatty acids with double bonds in the (n-16) to (n-11) position (e.g. petroselinic acid) are converted only very slowly by pancreatic lipase. This may lead to wrong results. 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 indicated below. Members of IEC and iSO maintain registers of currently valid International Standards. IsO 660:1996, Animal and vegetable fats and oils - Determination of acid value and of acidity. IsO 3696:1987, Water for analytical laboratory use - Specification and test methods. IsO 5508:1990, Animal and vegetable fats and oils - Analysis by gas chromatography of methyl esters of fatty acids. ational Organization for Standardization Not for Resale