1、BSI Standards PublicationBS ISO 18363-1:2015Animal and vegetable fats andoils Determination of fatty-acid-bound chloropropanediols(MCPDs) and glycidol by GC/MSPart 1: Method using fast alkalinetransesterification and measurement for 3-MCPD and differential measurement forglycidolBS ISO 18363-1:2015
2、BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 18363-1:2015.The UK participation in its preparation was entrusted to TechnicalCommittee AW/307, Oilseeds, animal and vegetable fats and oils andtheir by-products.A list of organizations represented on this commit
3、tee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2015. Published by BSI StandardsLimited 2015ISBN 978 0 580 82000 7ICS 67.200.10Co
4、mpliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 August 2015.Amendments issued since publicationDate Text affectedBS ISO 18363-1:2015 ISO 2015Animal and vegetable
5、fats and oils Determination of fatty-acid-bound chloropropanediols (MCPDs) and glycidol by GC/MS Part 1: Method using fast alkaline transesterification and measurement for 3-MCPD and differential measurement for glycidolCorps gras dorigines animale et vgtale Dtermination des esters de chloropropaned
6、iols (MCPD) et dacides gras et des esters de glycidol et dacides gras Partie 1: Mthode par transestrification alcaline rapide et mesure pour le chloro-3 propane-1,2-diol (3-MCPD) et par mesure diffrentielle pour le glycidolINTERNATIONAL STANDARDISO18363-1First edition2015-08-15Reference numberISO 18
7、363-1:2015(E)BS ISO 18363-1:2015ISO 18363-1:2015(E)ii ISO 2015 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2015, Published in SwitzerlandAll rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electroni
8、c or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Ge
9、neva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgBS ISO 18363-1:2015ISO 18363-1:2015(E)Foreword ivIntroduction v1 Scope . 12 Normative references 13 Terms and definitions . 14 Principle 25 Reagents 35.1 General . 35.2 Standard and reference compounds 35.3 Solvents
10、 . 35.4 Other reagents . 36 Apparatus . 47 Sample . 47.1 Sampling . 47.2 Preparation of the test sample 48 Procedure. 58.1 Spiking with surrogate standard and homogenization 58.2 Ester cleavage and glycidol transformation . 58.3 Matrix clean up . 58.4 Derivatization . 58.5 Gas chromatography/mass sp
11、ectrometry references . 69 Expression of results 610 Precision . 710.1 Interlaboratory test. 710.2 Repeatability . 810.3 Reproducibility . 811 Test report . 8Annex A (informative) Results of an collaborative trial . 9Bibliography .11 ISO 2015 All rights reserved iiiContents PageBS ISO 18363-1:2015IS
12、O 18363-1:2015(E)ForewordISO (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 subje
13、ct 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
14、) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be no
15、ted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying
16、 any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents).Any trade name used in this document is information given for the convenience of
17、 users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplem
18、entary information.The committee responsible for this document is ISO/TC 34, Food products, Subcommittee SC 11, Animal and vegetable fats and oils.ISO 18363 consists of the following parts, under the general title Animal and vegetable fats and oils Determination of fatty-acid-bound chloropropanediol
19、s (MCPDs) and glycidol by GC/MS Part 1: Method using fast alkaline transesterification and measurement for 3-MCPD and differential measurement for glycidolThe following parts are under preparation: Part 2: Method using alkaline transesterification and measurement for 2-MCPD, 3-MCPD and glycidol Part
20、 3: Method using acid transesterification and measurement for 2-MCPD, 3-MCPD and glycidoliv ISO 2015 All rights reservedBS ISO 18363-1:2015ISO 18363-1:2015(E)IntroductionISO 18363 is a set of International Standards which can be used for the determination of ester-bound MCPD and glycidol. There are
21、currently three International Standards which have been proposed and this introduction is a description of these methods, which can be used by the analyst to decide which methods are suitable for their application. The detailed application of each method is contained within the scope of the individu
22、al method.This part of ISO 18363 is a differential method equivalent to the DGF standard C-VI 18 (10) and identical to AOCS Official Method Cd 29c-13. Briefly, it is based on a fast alkaline catalysed release of 3-MCPD and glycidol from the ester derivatives. Glycidol is subsequently converted into
23、induced 3-MCPD. It consists of two parts. The first part (A) allows the determination of the sum of ester bound 3-MCPD and ester bound glycidol, whereas the second part (B) determines ester-bound 3-MCPD only. Both assays are based on the release of the target analytes 3-MCPD and glycidol from the es
24、ter bound form by an alkaline catalysed alcoholysis carried out at room temperature. In part A, an acidified sodium chloride solution is used to stop the reaction and subsequently convert the glycidol into induced 3-MCPD. Thus, 3-MCPD and glycidol become indistinguishable in part A. In part B, the r
25、eaction stop is achieved by the addition of an acidified chloride-free salt solution which also prevents the conversion of glycidol into induced MCPD. Thereby, part B allows the determination of the genuine 3-MCPD content. Finally, the glycidol content of the sample is proportional to the difference
26、 of both assays (A B) and can be calculated when the transformation ratio from glycidol to 3-MCPD has been determined. This part of ISO 18363 is applicable for the fast determination of ester bound 3-MCPD and glycidol in refined and non-refined vegetable oils and fats. This part of ISO 18363 can als
27、o apply to animal fats and used frying oils and fats, but a validation study has to be undertaken before the analysis of these matrices. Any free analytes within the sample would be included in the results, but the standard does not allow the distinction between free and bound analytes. However, as
28、of publication, research has not shown any evidence of a free analyte content as high as the esterified analyte content in refined vegetable oils and fats. In principle, this part of ISO 18363 can also be modified in such a way that the determination of 2-MCPD is feasible, but again, a validation st
29、udy has to be undertaken before the analysis of this analyte.The second part of the proposed International Standards for the determination of ester-bound MCPD and glycidol represents the AOCS Official Method Cd 29b-13. Briefly, it is based on a slow alkaline release of MCPD and glycidol from the est
30、er derivatives. Glycidol is subsequently converted into 3-MBPD. The second part of the proposed International Standards consists of two sample preparations that differ in the use of internal standards. Both parts can be used for the determination of ester bound 2-MCPD and 3-MCPD. In part A, a prelim
31、inary result for ester bound glycidol is determined. Because the 3-MCPD present in the sample will be converted to some minor extent into induced glycidol by the sample preparation, part B serves to quantify this amount of induced glycidol that is subsequently subtracted from the preliminary glycido
32、l result of part A. By the use of isotopically labelled free MCPD isomers in assay A and isotopically labelled ester bound 2-MCPD and 3-MCPD in part B, the efficiency of ester cleavage can be monitored. Both assays A and B are based on the release of the target analytes 2-MCPD, 3-MCPD, and glycidol
33、from the ester bound form by a slow alkaline catalysed alcoholysis in the cold. In both sample preparations, the reaction is stopped by the addition of an acidified concentrated sodium bromide solution so as to convert the unstable and volatile glycidol into 3-MBPD which shows comparable properties
34、to 3-MCPD with regard to its stability and chromatographic performance. Moreover, the major excess of bromide ions prevents the undesired formation of 3-MCPD from glycidol in the case of samples which contain naturally occurring amounts of chloride. The second part of the proposed standards is appli
35、cable for the determination of ester bound 3-MCPD, 2-MCPD, and glycidol in refined and unrefined vegetable oils and fats. The second part of the proposed International Standards can also apply to animal fats and used frying oils and fats, but a validation study has to be undertaken before the analys
36、is of these matrices. Any free analytes within the sample would be included in the results, but the standard does not allow the distinction between free and bound analytes. However, as of publication, research has not shown any evidence of a free analyte content as high as the esterified analyte con
37、tent in vegetable oils and fats.The third part of the proposed International Standards for the determination of ester-bound MCPD and glycidol represents the AOCS Official Method Cd 29a-13. Briefly, it is based on the conversion of glycidyl esters into 3-MBPD esters and a slow acidic catalysed releas
38、e of MCPD and MBPD from the ISO 2015 All rights reserved vBS ISO 18363-1:2015ISO 18363-1:2015(E)ester derivatives. The third part of the proposed International Standards is based on a single sample preparation in which glycidyl esters are converted into MBPD monoesters, and subsequently, the free an
39、alytes 2-MCPD, 3-MCPD, and 3-MBPD are released by a slow acid-catalysed alcoholysis. The 3-MBPD represents the genuine content of bound glycidol. The third part of the proposed International Standards can be applied for the determination of ester bound 2-MCPD, 3-MCPD, and glycidol in refined and non
40、-refined vegetable oils and fats. The third part of the proposed International Standards can also apply to animal fats and used frying oils and fats, but a validation study has to be undertaken before the analysis of these matrices. The method is suited for the analysis of bound (esterified) analyte
41、s, but if required, the third part of the proposed International Standards can be also performed without the initial conversion of glycidyl esters. In such a setup, both free and bound 2-MCPD and 3-MCPD forms would be included in the results and the amount of free analytes can be calculated as a dif
42、ference between two determinations performed in both setups. However, as of publication, research has not shown any evidence of a free analyte content as high as the esterified analyte content in vegetable oils and fats.vi ISO 2015 All rights reservedBS ISO 18363-1:2015INTERNATIONAL STANDARD ISO 183
43、63-1:2015(E)Animal and vegetable fats and oils Determination of fatty-acid-bound chloropropanediols (MCPDs) and glycidol by GC/MS Part 1: Method using fast alkaline transesterification and measurement for 3-MCPD and differential measurement for glycidol1 ScopeThis part of ISO 18363 describes a proce
44、dure for the indirect determination of 3-MCPD esters (bound 3-MCPD) and possible free 3-MCPD after alkaline catalysed ester cleavage and derivatization with phenylboronic acid (PBA). Furthermore, this part of ISO 18363 enables the indirect determination of glycidyl esters (bound glycidol) under the
45、assumption that no other substances are present that react at room temperature with inorganic chloride to generate 3-MCPD.This part of ISO 18363 is applicable to solid and liquid fats and oils. Milk and milk products (or fat coming from milk and milk products) are excluded from the scope of this par
46、t of ISO 18363.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (inclu
47、ding any amendments) applies.ISO 3696, Water for analytical laboratory use Specification and test methods3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.3.1bound 3-MCPDsum of all 3-MCPD derivatives being cleaved by alkaline catalysed alcoholysis (e
48、specially fatty acid esters) according to the reference methodNote 1 to entry: The content of 3-MCPD is calculated and reported as a mass fraction, in milligrams per kilogram (mg/kg).Note 2 to entry: In fats and oils, the amount of free 3-MCPD which can possibly occur is generally negligibly low but
49、 has a bearing on the result.3.2bound glycidolsum of all glycidyl derivatives being cleaved by alkaline catalysed alcoholysis (especially fatty acid esters) according to the specified standardNote 1 to entry: The content of glycidol is calculated and reported as a mass fraction, in milligrams per kilogram (mg/kg). ISO 2015 All rights reserved 1BS ISO 18363-1:2015ISO 18363-1:2015(E)Note 2 to entry: The presence of free glycidol in fats and oils is unlikely because of the instability of this compound.4 PrincipleFor the determination of t