ISO 18363-3:2024

Norme
internationale
ISO 18363-3
Deuxième édition
Corps gras d'origines animale et
2024-06
végétale — Détermination des
esters de chloropropanediols
(MCPD) et d'acides gras et des
esters de glycidol et d'acides gras
par CPG/SM —
Partie 3:
Méthode par transestérification
acide et mesure du 2-MCPD, du
3-MCPD et du glycidol
Animal and vegetable fats and oils — Determination of fatty-acid-
bound chloropropanediols (MCPDs) and glycidol by GC/MS —
Part 3: Method using acid transesterification and measurement
for 2-MCPD, 3-MCPD and glycidol
Numéro de référence
DOCUMENT PROTÉGÉ PAR COPYRIGHT
© ISO 2024
Tous droits réservés. Sauf prescription différente ou nécessité dans le contexte de sa mise en œuvre, aucune partie de cette
publication ne peut être reproduite ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique,
y compris la photocopie, ou la diffusion sur l’internet ou sur un intranet, sans autorisation écrite préalable. Une autorisation peut
être demandée à l’ISO à l’adresse ci-après ou au comité membre de l’ISO dans le pays du demandeur.
ISO copyright office
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CH-1214 Vernier, Genève
Tél.: +41 22 749 01 11
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Web: www.iso.org
Publié en Suisse
ii
Sommaire Page
Avant-propos .iv
Introduction .v
1 Domaine d’application . 1
2 Références normatives . 1
3 Termes et définitions . 1
4 Principe. 2
5 Réactifs . 2
5.1 Composés étalons et composés de référence .2
5.2 Solutions étalons .3
5.2.1 Généralités .3
5.2.2 Solutions mères (1 mg/ml) .3
5.2.3 Solutions de travail .3
5.3 Autres réactifs.4
5.4 Solutions de réactifs .4
6 Appareillage . 5
7 Échantillon . 6
7.1 Échantillonnage .6
7.2 Préparation de l’échantillon pour essai .6
8 Mode opératoire . 6
8.1 Préparation de l’échantillon pour essai .6
8.2 Préparation de la droite d’étalonnage .7
8.3 Références relatives à la chromatographie en phase gazeuse/spectrométrie de masse
(CPG/SM) .7
9 Expression des résultats . 8
9.1 Quantification des esters de 3-MCPD .8
9.2 Quantification des esters de 2-MCPD .9
9.3 Quantification des esters de glycidol .10
10 Fidélité .11
10.1 Généralités .11
10.2 Répétabilité .11
10.3 Reproductibilité entre jours .11
11 Rapport d’essai .11
Annexe A (informative) Construction des droites d’étalonnage .12
Annexe B (informative) Résultats de l’essai interlaboratoires .16
Bibliographie .18

iii
Avant-propos
L’ISO (Organisation internationale de normalisation) est une fédération mondiale d’organismes nationaux
de normalisation (comités membres de l’ISO). L’élaboration des Normes internationales est en général
confiée aux comités techniques de l’ISO. Chaque comité membre intéressé par une étude a le droit de faire
partie du comité technique créé à cet effet. Les organisations internationales, gouvernementales et non
gouvernementales, en liaison avec l’ISO participent également aux travaux. L’ISO collabore étroitement avec
la Commission électrotechnique internationale (IEC) en ce qui concerne la normalisation électrotechnique.
Les procédures utilisées pour élaborer le présent document et celles destinées à sa mise à jour sont
décrites dans les Directives ISO/IEC, Partie 1. Il convient, en particulier, de prendre note des différents
critères d’approbation requis pour les différents types de documents ISO. Le présent document a
été rédigé conformément aux règles de rédaction données dans les Directives ISO/IEC, Partie 2 (voir
www.iso.org/directives).
L’ISO attire l’attention sur le fait que la mise en application du présent document peut entraîner l’utilisation
d’un ou de plusieurs brevets. L’ISO ne prend pas position quant à la preuve, à la validité et à l’applicabilité de
tout droit de brevet revendiqué à cet égard. À la date de publication du présent document, l’ISO n’avait pas
reçu notification qu’un ou plusieurs brevets pouvaient être nécessaires à sa mise en application. Toutefois,
il y a lieu d’avertir les responsables de la mise en application du présent document que des informations
plus récentes sont susceptibles de figurer dans la base de données de brevets, disponible à l’adresse
www.iso.org/brevets. L’ISO ne saurait être tenue pour responsable de ne pas avoir identifié tout ou partie de
tels droits de propriété.
Les appellations commerciales éventuellement mentionnées dans le présent document sont données pour
information, par souci de commodité, à l’intention des utilisateurs et ne sauraient constituer un engagement.
Pour une explication de la nature volontaire des normes, la signification des termes et expressions
spécifiques de l’ISO liés à l’évaluation de la conformité, ou pour toute information au sujet de l’adhésion de
l’ISO aux principes de l’Organisation mondiale du commerce (OMC) concernant les obstacles techniques au
commerce (OTC), voir www.iso.org/avant-propos.
Le présent document a été élaboré par le comité technique ISO/TC 34, Produits alimentaires, sous-comité
SC 11, Corps gras d’origines animale et végétale, en collaboration avec le comité technique CEN/TC 307,
Oléagineux, corps gras d’origines végétale et animale et leurs co-produits — Méthodes d’échantillonnage et
d’analyse, du Comité européen de normalisation (CEN) conformément à l’Accord de coopération technique
entre l’ISO et le CEN (Accord de Vienne).
Cette deuxième édition annule et remplace la première édition (ISO 18363-3:2017), dont elle constitue une
révision mineure.
Les modifications principales sont les suivantes:
— révision du texte de l’Introduction pour qu’il soit en cohérence avec l’ISO 18363-4:2021.
Une liste de toutes les parties de la série ISO 18363 se trouve sur le site web de l’ISO.
Il convient que l’utilisateur adresse tout retour d’information ou toute question concernant le présent
document à l’organisme national de normalisation de son pays. Une liste exhaustive desdits organismes se
trouve à l’adresse www.iso.org/fr/members.html.

iv
Introduction
[1]
La série ISO 18363 peut être utilisée pour la détermination des esters de MCPD et de glycidol. La présente
introduction décrit les méthodes spécifiées dans les différentes parties afin de permettre à l’analyste de
décider des méthodes appropriées en fonction de son application. L’application détaillée de chaque méthode
figure dans le domaine d’application de chaque méthode concernée.
[2]
L’ISO 18363-1 est une méthode différentielle équivalente à la norme C-VI 18 (10) de la DGF et identique
[3]
à la méthode officielle Cd 29c-13 de l’AOCS. En résumé, elle repose sur la libération rapide par catalyse
alcaline de 3-MCPD et de glycidol à partir de leurs dérivés esters. Le glycidol est par la suite converti en
3-MCPD. Elle comprend deux parties. La première partie (A) permet de déterminer la somme des esters de
3-MCPD et des esters de glycidol, tandis que la seconde partie (B) ne détermine que les esters de 3-MCPD.
Les deux analyses reposent sur la libération des analytes cibles, le 3-MCPD et le glycidol, à partir des esters
par alcoolyse en présence d’un catalyseur alcalin à température ambiante. Dans la partie A, une solution
acidifiée de chlorure de sodium est utilisée pour interrompre la réaction qui induit par la suite la conversion
du glycidol en 3-MCPD. Il n’est par conséquent plus possible de faire la distinction entre le 3-MCPD et le
glycidol dans la partie A. Dans la partie B, la réaction est interrompue par ajout d’une solution saline
acidifiée exempte de chlorure qui évite aussi la conversion du glycidol en MCPD. La partie B permet ainsi de
déterminer la véritable teneur en 3-MCPD. Enfin, la teneur en glycidol de l’échantillon est proportionnelle
à la différence entre les deux analyses (A – B) et peut être calculée lorsque le coefficient de transformation
du glycidol en 3-MCPD a été déterminé. L’ISO 18363-1 est applicable à la détermination rapide des esters
de 3-MCPD et de glycidol dans les corps gras d’origine végétale raffinés et non raffinés. L’ISO 18363-1 peut
également s’appliquer aux graisses animales et aux huiles de friture usagées, mais une étude de validation
doit être menée avant de procéder à l’analyse de ces matrices. Les analytes libres éventuellement contenus
dans l’échantillon sont habituellement inclus dans les résultats, mais le document ne permet pas de faire
la distinction entre les analytes libres et les analytes liés
...

FINAL DRAFT
International
Standard
ISO/FDIS 18363-3
ISO/TC 34/SC 11
Animal and vegetable fats and
Secretariat: BSI
oils — Determination of fatty-acid-
Voting begins on:
bound chloropropanediols (MCPDs)
2024-03-12
and glycidol by GC/MS —
Voting terminates on:
2024-06-04
Part 3:
Method using acid
transesterification and
measurement for 2-MCPD, 3-MCPD
and glycidol
Corps gras d'origines animale et végétale — Détermination des
esters de chloropropanediols (MCPD) et d'acides gras et des
esters de glycidol et d'acides gras par CPG/SM —
Partie 3: Méthode par transestérification acide et mesure du
2-MCPD, du 3-MCPD et du glycidol
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/CEN PARALLEL PROCESSING LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
Reference number
ISO/FDIS 18363-3:2024(en) © ISO 2024

FINAL DRAFT
ISO/FDIS 18363-3:2024(en)
International
Standard
ISO/FDIS 18363-3
ISO/TC 34/SC 11
Animal and vegetable fats and
Secretariat: BSI
oils — Determination of fatty-acid-
Voting begins on:
bound chloropropanediols (MCPDs)
and glycidol by GC/MS —
Voting terminates on:
Part 3:
Method using acid
transesterification and
measurement for 2-MCPD, 3-MCPD
and glycidol
Corps gras d'origines animale et végétale — Détermination des
esters de chloropropanediols (MCPD) et d'acides gras et des
esters de glycidol et d'acides gras par CPG/SM —
Partie 3: Méthode par transestérification acide et mesure du
2-MCPD, du 3-MCPD et du glycidol
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
© ISO 2024
IN ADDITION TO THEIR EVALUATION AS
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/CEN PARALLEL PROCESSING
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
or ISO’s member body in the country of the requester.
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland Reference number
ISO/FDIS 18363-3:2024(en) © ISO 2024

ii
ISO/FDIS 18363-3:2024(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Reagents . 2
5.1 Standard and reference compounds .2
5.2 Standard solutions .3
5.2.1 General .3
5.2.2 Stock solutions (1 mg/ml) .3
5.2.3 Working solutions .3
5.3 Other reagents .4
5.4 Reagent solutions .4
6 Apparatus . 5
7 Sample . 5
7.1 Sampling .5
7.2 Preparation of the test sample .5
8 Procedure . 6
8.1 Test sample preparation .6
8.2 Preparation of the calibration curve .7
8.3 Gas chromatography/mass spectrometry references .7
9 Expression of results . 8
9.1 Quantification of 3-MCPD esters .8
9.2 Quantification of 2-MCPD esters .8
9.3 Quantification of glycidyl esters .9
10 Precision . 10
10.1 General .10
10.2 Repeatability .10
10.3 Between-day reproducibility . .10
11 Test report . 10
Annex A (informative) Construction of the calibration curves .11
Annex B (informative) Results of the interlaboratory test .15
Bibliography . 17

iii
ISO/FDIS 18363-3:2024(en)
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.
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 document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 34, Food products, Subcommittee SC 11,
Animal and vegetable fats and oils, in collaboration with the European Committee for Standardization (CEN)
Technical Committee CEN/TC 307, Oilseeds, vegetable and animal fats and oils and their by-products – Methods
of sampling and analysis, in accordance with the Agreement on technical cooperation between ISO and CEN
(Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 18363-3:2017), of which it constitutes a minor
revision. The changes are as follows:
— the text of the Introduction has been revised to be consistent with ISO 18363-4:2021.
A list of all parts in the ISO 18363 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
ISO/FDIS 18363-3:2024(en)
Introduction
The ISO 18363 series can be used for the determination of ester-bound MCPD and glycidol. This introduction
describes the methods specified in the different parts so that the analyst can decide which methods are
suitable for application. The detailed application of each method is contained within the scope of each
individual method.
[11]
ISO 18363-1 is a differential method equivalent to DGF standard C-VI 18 (10) and identical to AOCS
[10]
Official Method Cd 29c-13 . In brief, it is based on a fast alkaline catalysed release of 3-MCPD and glycidol
from the ester derivatives. Glycidol is subsequently converted into 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 ester-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
...

ISO/FDIS 18363-3
ISO/TC 34/SC 11
Date: 2024-01
ISO 18363-3:2017(E)
ISO/TC 34/SC 11
Secretariat: BSI
Date: 2024-02-27
Animal and vegetable fats and oils — Determination of fatty-acid-
bound chloropropanediols (MCPDs) and glycidol by GC/MS —
Part 3:
Method using acid transesterification and measurement for 2-MCPD,
3-MCPD and glycidol
Corps gras d'origines animale et végétale — Détermination des esters de chloropropanediols (MCPD) et
d'acides gras et des esters de glycidol et d'acides gras par CPG/SM —
Partie 3: Méthode par transestérification acide et mesure pour ledu 2-MCPD, ledu 3-MCPD et ledu glycidol
FDIS stage
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication
may be reproduced or utilized otherwise in any form or by any means, electronic 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 ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: + 41 22 749 01 11
E-mail: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ISO/FDIS 18363-3:2024(en)
Contents
Foreword . iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Reagents . 2
5.1 Standard and reference compounds . 2
5.2 Standard solutions . 3
5.2.1 General . 3
5.2.2 Stock solutions (1 mg/ml) . 3
5.2.3 Working solutions . 3
5.3 Other reagents . 4
5.4 Reagent solutions . 4
6 Apparatus . 5
7 Sample . 5
7.1 Sampling . 5
7.2 Preparation of the test sample . 5
8 Procedure . 6
8.1 Test sample preparation . 6
8.2 Preparation of the calibration curve . 7
8.3 Gas chromatography/mass spectrometry references . 7
9 Expression of results . 8
9.1 Quantification of 3-MCPD esters . 8
9.2 Quantification of 2-MCPD esters . 8
9.3 Quantification of glycidyl esters . 9
10 Precision . 10
10.1 General . 10
10.2 Repeatability . 10
10.3 Between-day reproducibility . 10
11 Test report . 10
Annex A (informative) Construction of the calibration curves . 11
Annex B (informative) Results of the interlaboratory test . 18
Bibliography . 20

iii
ISO/FDIS 18363-3:2024(en)
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.
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 documentsdocument should be noted. This document was drafted in accordance with the editorial rules
of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawnISO draws attention to the possibility that some of the elementsimplementation of this
document may beinvolve the subjectuse of (a) patent(s). ISO takes no position concerning the evidence,
validity or applicability of any claimed patent rights in respect thereof. As of the date of publication of this
document, ISO had not received notice of (a) patent(s) which may be required to implement this document.
However, implementers are cautioned that this may not represent the latest information, which may be
obtained from the patent database available at www.iso.org/patents. ISO shall not be held responsible for
identifying 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 users and does not
constitute an endorsement.
For an explanation onof the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html)
see the following URL: www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 34, Food products, Subcommittee SC 11, Animal
and vegetable fats and oils., in collaboration with the European Committee for Standardization (CEN) Technical
Committee CEN/TC 307, Oilseeds, vegetable and animal fats and oils and their by-products – Methods of
sampling and analysis, in accordance with the Agreement on technical cooperation between ISO and CEN
(Vienna Agreement).
AThis second edition cancels and replaces the first edition (ISO 18363-3:2017), of which it constitutes a minor
revision was performed to bring . The changes are as follows:
— the text of the Introduction in linehas been revised to be consistent with the latest part in theISO 18363
series. -4:2021.
A list of all parts in the ISO 18363 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
ISO/FDIS 18363-3:2024(en)
Introduction
The ISO 18363 series is a family of International Standards which can be used for the determination of ester-
bound MCPD and glycidol. This introduction describes the methods specified in the four documents currently
published or proposeddifferent parts so that the analyst can decide which methods are suitable for
application. The detailed application of each method is contained within the scope of each individual method.
[11]
ISO 18363-1 is a differential method equivalent to the DGF standard C-VI 18 (10) and identical to AOCS
[10]
Official Method Cd 29c-13 . In brief, it is based on a fast alkaline catalysed release of 3-MCPD and glycidol
from the ester derivatives. Glycidol is subsequently converted into 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 ester-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 reaction stop is achieved by the addition of an acidified chloride-free
salt solution which also prevents the conversion of glycidol into induced MCPD. Consequently, part B allows
the determination of the genuine 3-MCPD content. Finally, the glycidol content of the sample is proportional
to the difference of both assays (A – B) and can be calculated when the transformation ratio from glycidol to
3-MCPD has been determined. ISO 18363-1 is applicable to the fast determination of ester-bound 3-MCPD and
glycidol in refined and non-refined vegetable oils and fats. ISO 18363-1 can also apply to animal fats and used
frying oils and fats, but a validation study must be undertaken before the analysis of these matrices. Any free
analytes within the sample would be included in the results, but the document does not allow the distinction
between free and bound analytes. However, as of publication of this document, 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, ISO 18363-1 can also be modified in such a way that the determination of 2-MCPD is feasible, but
again, a validation study must be undertaken before the analysis of this analyte.
[9]
ISO 18363-2 represents the AOCS Official Method Cd 29b-13 . In brief, it is based on a slow alkaline release
of MCPD and glycidol from the ester derivatives. Glycidol is subsequently converted into 3-MBPD. ISO 18363-
2 consists of two sample preparations that differ in the use of internal standards. Both preparations are used
for the determination of ester-bound 2-MCPD and 3-MCPD. In part A, a preliminary result for ester-bound
glycidol is determined. Because the 3-MCPD present in the sample is 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 glycidol result of part A. By the use of isotopically labelled free
MCPD isomers in assay A and isotopi
...