ISO/FDIS 16756

Milk and milk products — Guidance for the application of Carr-Purcell-Meiboom-Gill (CPMG) pulsed time-domain nuclear magnetic resonance (TD-NMR) spectroscopy for fat determination

This International Standard provides guidance on the determination of total fat content in milk and milk products, such as milk, cream, yogurt, ice cream, processed cheese, cheese, and milk powders, by the low-resolution nuclear magnetic resonance (NMR) using CPMG (Carr-Purcell-Meiboom-Gill) Pulse sequence to optimize the specific response of fat molecules. The described guidance is applicable to the analysis of any milk and milk products, regardless of source (species or region). It is applicable to dry samples (i.e. moisture ≤ 10 %) and liquid or wet samples which have been pre-dried such that all appreciable water has been removed. The NMR with CPMG Pulse Sequence analyses glycerolipids, which produces fat results comparable to the total fat result of standard fat extraction techniques, without the need for matrix specific calibrations while meeting the precision criteria listed in guideline. The application is not limited by sample viscosity, colour, or particle size.

Laits et produits laitiers — Lignes directrices pour l’application de la spectroscopie par résonance magnétique nucléaire dans le domaine temporel (TD-RMN) à impulsions Carr-Purcell-Meiboom-Gill (CPMG) pour le dosage de la matière grasse

General Information

• Status: Not Published
• ICS: 67.100.01 - Milk and milk products in general
• Technical Committee: ISO/TC 34/SC 5 - Milk and milk products
• Drafting Committee: ISO/TC 34/SC 5 - Milk and milk products
• Current Stage: 5020 - FDIS ballot initiated: 2 months. Proof sent to secretariat
• Start Date: 15-Jul-2024
• Completion Date: 15-Jul-2024

Standards Content (Sample)

FINAL DRAFT
International
Standard
IDF 259
ISO/TC 34/SC 5
Milk and milk products — Guidance
Secretariat: NEN
for the application of Carr-Purcell-
Voting begins on:
Meiboom-Gill (CPMG) pulsed time-
2024-07-15
domain nuclear magnetic resonance
Voting terminates on:
(TD-NMR) spectroscopy for fat
2024-09-09
determination
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
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 numbers
IDF 259:2024(en) © ISO and IDF 2024

FINAL DRAFT
International
Standard
IDF 259
ISO/TC 34/SC 5
Milk and milk products — Guidance
Secretariat: NEN
for the application of Carr-Purcell-
Voting begins on:
Meiboom-Gill (CPMG) pulsed time-
domain nuclear magnetic resonance
Voting terminates on:
(TD-NMR) spectroscopy for fat
determination
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
© ISO and IDF 2024
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
IN ADDITION TO THEIR EVALUATION AS
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
or ISO’s member body in the country of the requester.
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
ISO copyright office International Dairy Federation TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
CP 401 • Ch. de Blandonnet 8 Silver Building • Bd Auguste Reyers 70/B
CH-1214 Vernier, Geneva B-1030 Brussels
Phone: [phone] Phone: [phone]
Fax: [phone]
Email: [e-mail] Email: [e-mail]
Website: www.iso.org Website: www.fil-idf.org
Reference numbers
Published in Switzerland ISO/FDIS 16756:2024(en)
IDF 259:2024(en) © ISO and IDF 2024

ii
IDF 259:2024(en)
Contents Page
Forewords .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Principal characteristics of NMR instruments . 2
6 Apparatus . 2
7 Factors affecting the measurements . 3
7.1 Instrument factors .3
7.1.1 Stability .3
7.1.2 Homogeneity of the magnetic field .3
7.1.3 Magnet temperature .3
7.1.4 Carryover .3
7.1.5 Non-glycerolipids .4
7.2 Physicochemical factors .4
7.2.1 Sample temperature . .4
7.2.2 Sample pre-drying .4
8 Validation and routine stability of the instrument . 4
8.1 Standard reference material comparison .4
8.2 System settings .4
9 Sampling . 5
10 Procedure . 5
10.1 Preparation of test samples .5
10.1.1 General aspects .5
10.1.2 Pre-drying of the sample .5
10.1.3 Preparation of the sample for NMR analysis .5
10.2 Measurement .6
11 Checking instrument stability . 6
11.1 Control sample .6
11.2 Instrument diagnostics .6
12 Precision and accuracy . 6
12.1 General .6
12.2 Limit of detection (LoD) and limit of quantification (LoQ) .6
12.3 Repeatability .6
12.4 Intralaboratory reproducibility .7
12.5 Accuracy .7
13 Test report . 8
Bibliography . 9

iii
IDF 259:2024(en)
Forewords
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 5, Milk
and milk products, and the International Dairy Federation (IDF). It is being published jointly by ISO and IDF.
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
IDF 259:2024(en)
IDF (the International Dairy Federation) is a non-profit private sector organization representing the
interests of various stakeholders in dairying at the global level. IDF members are organized in National
Committees, which are national associations composed of representatives of dairy-related national interest
groups including dairy farmers, dairy processing industry, dairy suppliers, academics and governments/
food control authorities.
ISO and IDF collaborate closely on all matters of standardization relating to methods of analysis and
sampling for milk and milk products. Since 2001, ISO and IDF jointly publish their International Standards
using the logos and reference numbers of both organizations.
IDF draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IDF 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, IDF 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. IDF shall not be held responsible for identifying any or all such patent rights.
Any trade name
...

revISO/DISISO/FDIS 16756
IDF 259
ISO/TC 34/SC 5
Secretariat: NEN
Date: 2024-04-1107-01
Milk and milk products — Guidance for the application of Carr-
Purcell-Meiboom-Gill (CPMG) pulsed time-domain nuclear magnetic
resonance (TD-NMR) spectroscopy for fat determination
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: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
Contents
Forewords . iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Principal characteristics of NMR instruments . 2
6 Apparatus . 2
7 Factors affecting the measurements . 3
7.1 Instrument factors . 3
7.1.1 Stability . 3
7.1.2 Homogeneity of the magnetic field . 3
7.1.3 Magnet temperature . 3
7.1.4 Carryover . 3
7.1.5 Non-glycerolipids . 4
7.2 Physicochemical factors . 4
7.2.1 Sample temperature . 4
7.2.2 Sample pre-drying . 4
8 Validation and routine stability of the instrument . 4
8.1 Standard reference material comparison . 4
8.2 System settings . 4
9 Sampling . 5
10 Procedure . 5
10.1 Preparation of test samples . 5
10.1.1 General aspects . 5
10.1.2 Pre-drying of the sample . 5
10.1.3 Preparation of the sample for NMR analysis . 5
10.2 Measurement . 6
11 Checking instrument stability . 6
11.1 Control sample . 6
11.2 Instrument diagnostics . 6
12 Precision and accuracy . 6
12.1 General . 6
12.2 Limit of detection (LoD) and limit of quantification (LoQ) . 7
12.3 Repeatability . 7
12.4 Intralaboratory reproducibility . 7
12.5 Accuracy . 8
13 Test report . 8
Bibliography . 10

iii
Forewords
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 5, Milk and
milk products, and the International Dairy Federation (IDF). It is being published jointly by ISO and IDF.
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
IDF (the International Dairy Federation) is a non-profit private sector organization representing the
interests of various stakeholders in dairying at the global level. IDF members are organized in National
Committees, which are national associations composed of representatives of dairy-related national interest
groups including dairy farmers, dairy processing industry, dairy suppliers, academics and governments/food
control authorities.
ISO and IDF collaborate closely on all matters of standardization relating to methods of analysis and sampling
for milk and milk products. Since 2001, ISO and IDF jointly publish their International Standards using the
logos and reference numbers of both organizations.
IDF draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IDF 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, IDF 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. IDF 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.
This document was prepared by the IDF Standing Committee on Analytical Methods for Composition and ISO
Technical Committee ISO/TC 34, Food products, Subcommittee SC 5, Milk and milk products. It is being
published jointly by ISO and IDF.
The work was carried out by the IDF/ISO Action Team C56 of the Standing Committee on Analytical Methods
for Composition under the aegis of its project leaders Mr P.A. Golay (CH) and Mr D. Darrell (US).
v
Milk and milk products — Guidance for the application of Carr-
Purcell-Meiboom-Gill (CPMG) pulsed time-domain nuclear magnetic
resonance (TD-NMR) spectroscopy for fat determination
1 Scope
This document providesgives guidance on the determination of total fat content in milk and milk-based
products, such as milk, cream, yogurt, ice cream, processed dairy, cheese, and dairy powders by low-resolution
nuclear magnetic resonance (NMR) using Carr-Purcell-Meiboom-Gill (CPMG) Pulse sequence to optimize the
specific response of fat molecules.
The described guidanceThis document is applicable to the analysis of any milk and milk-based products,
regardless of source (species or region). It is applicable to dry samples (i.e. moisture content ≤ 10 %) and
liquid or wet samples which have been pre-dried such that all appreciable water has been removed. The NMR
with CPMG pulse sequence analyses glycerolipids, which produces fat results comparable to the total fat result
of standard fat extraction techniques, without the need for matrix specific calibrations while meeting the
precision criteria listed in Clause 12of this document.
The application is not limited by sample viscosity, colour, or particle size.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at https://www.electropedia.org/
3.1
time-domain nuclear magnetic resonance (TD-NMR) spectroscopy
TD-NMR spectroscopy
technique where the intensity and speed of magnetic resonance signal decay of atomic nuclei are used to
determine physical and chemical properties of atoms and molecules.
Note 1 to entry: Intensity of magnetic resonance should correlate to quantity of the atomic nuclei present in the sample,
whereas speed of magnetic resonance signal decay inversely correlates to the movement of the molecule where the signal
originated, which can be aligned with the type of molecule.
Note 1 2 to entry: When used under the conditions defined in this document, NMR spectroscopy is able to provide the
total fat (3.2) value specified in 3.2.
3.2
total fat
class of compounds that are generally soluble in organic solvents and largely insoluble in water
Note 1 to entry: Fats are principally composed of triesters of glycerol and fatty acids (i.e. triacylglycerols), but contain
also minor lipids (i.e. diacylglycerols, monoacylglycerols, phospholipids, sterols). Fats can be either solid or liquid, though
commonly the term fat is used to refer to the solid f
...