ISO/FDIS 10565

• Abstract:

  This International Standard specifies a rapid method for the determination of the oil and water contents of commercial oilseeds using pulsed nuclear magnetic resonance (NMR). It is applicable to rapeseeds, soya beans, linseeds and sunflower seeds with a water content less than 10 %. For seeds with higher water contents, drying is necessary before the oil content can be determined by pulsed NMR. NOTE 1 This method has been tested with rapeseeds, soya beans, linseeds and sunflower seeds. This does not, however, preclude its applicability to other commercial seeds whose oil is liquid at the temperature of measurement. NOTE 2 The reproducibility values are generally higher than those obtained by the drying method (ISO 665)

• Status: Not Published
• ICS: 67.200.20 - Oilseeds
• Technical Committee: ISO/TC 34/SC 2 - Oleaginous seeds and fruits and oilseed meals
• Drafting Committee: ISO/TC 34/SC 2 - Oleaginous seeds and fruits and oilseed meals
• Current Stage: 5020 - FDIS ballot initiated: 2 months. Proof sent to secretariat
• Start Date: 24-Jun-2026
• Completion Date: 24-Jun-2026

• Consolidates: FprEN ISO 10565 - Oilseeds - Simultaneous determination of oil and water contents - Method using pulsed nuclear magnetic resonance spectrometry (ISO/FDIS 10565:2026)
• Effective Date: 12-Feb-2026
• Consolidates: ISO 9809-4:2021 - Gas cylinders — Design, construction and testing of refillable seamless steel gas cylinders and tubes — Part 4: Stainless steel cylinders with an R m value of less than 1 100 MPa
• Effective Date: 03-Sep-2022
• Revises: ISO 10565:1998 - Oilseeds — Simultaneous determination of oil and water contents — Method using pulsed nuclear magnetic resonance spectrometry
• Effective Date: 20-Aug-2022

Overview

ISO/FDIS 10565:2026 defines a rapid and reliable method for the simultaneous determination of oil and water content in commercial oilseeds using pulsed nuclear magnetic resonance (NMR) spectrometry. This International Standard, developed by ISO Technical Committee 34/SC 2, is applicable to key oilseed crops such as rapeseeds, soya beans, linseeds, and sunflower seeds, provided their water content is below the specified thresholds (typically less than 10% for most seeds, and 14% for soya beans). If seed moisture exceeds these limits, a drying step must be performed prior to NMR analysis. This standard offers significant advantages for quality assurance and process control in oilseed production, commercial trade, and food processing.

Key Topics

• Simultaneous Analysis: The standard details a procedure that enables the rapid and concurrent measurement of both oil and water in oilseeds using pulsed NMR technology, eliminating the need for separate tests.
• Sample Preparation: Guidelines are provided for proper sample conditioning, calibration requirements, and moisture adjustment for samples with high water content.
• Calibration and Measurement: ISO/FDIS 10565 emphasizes robust calibration procedures (using at least three samples of known composition) to ensure accurate readings, referencing authoritative methods such as ISO 659 for oil and ISO 665 for moisture determination.
• Precision and Repeatability: Defined precision criteria (repeatability and reproducibility) ensure that results are consistent within and across laboratories, backed by interlaboratory validation.
• Applicability: While validated on principal commercial oilseeds, the method may be applicable to other seeds with liquid oil at measurement temperatures, broadening its industrial relevance.

Applications

The practical value of ISO/FDIS 10565 for the oilseed industry includes:

• Quality Control: Enables grain traders, processors, and laboratories to quickly determine oil and moisture content, supporting purchase decisions and internal quality standards.
• Process Optimization: Assists in monitoring oilseed processing stages, including extraction, drying, and storage, by providing real-time, accurate composition analysis.
• Compliance and Reporting: Facilitates the preparation of standardized test reports, ensuring traceability and transparency in compliance with industry regulations.
• Research and Breeding: Supports breeders and researchers in screening new varieties for oil yield and stability under different storage conditions.
• Trade and Commercial Transactions: Standardized measurement helps resolve disputes and ensures consistency in contract specifications for oilseed purchases and sales.

Related Standards

The method prescribed in ISO/FDIS 10565 aligns with and refers to several related international standards:

• ISO 659: Oilseeds - Determination of oil content (Reference method)
• ISO 665: Oilseeds - Determination of moisture and volatile matter content
• ISO 658: Oilseeds - Determination of content of impurities
• ISO 664: Oilseeds - Reduction of laboratory sample to test sample
• ISO 21294: Oilseeds - Manual or automatic discontinuous sampling

Together, these standards form a comprehensive framework for oilseed analysis, offering harmonized procedures for sampling, preparation, and compositional testing.

---

By adopting ISO/FDIS 10565, industry stakeholders benefit from improved efficiency, accuracy, and confidence in the determination of oil and water content in oilseeds, strengthening quality assurance and competitiveness in the global market.

FINAL DRAFT
International
Standard
ISO/TC 34/SC 2
Oilseeds — Simultaneous
Secretariat: AFNOR
determination of oil and water
Voting begins on:
contents — Method using pulsed
2026-06-24
nuclear magnetic resonance
Voting terminates on:
spectrometry
2026-08-19
Graines oléagineuses — Détermination simultanée de la teneur
en huile et en eau — Méthode par spectrométrie par résonance
magnétique nucléaire pulsée
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
FINAL DRAFT
International
Standard
ISO/TC 34/SC 2
Oilseeds — Simultaneous
Secretariat: AFNOR
determination of oil and water
Voting begins on:
contents — Method using pulsed
nuclear magnetic resonance
Voting terminates on:
spectrometry
Graines oléagineuses — Détermination simultanée de la teneur
en huile et en eau — Méthode par spectrométrie par résonance
magnétique nucléaire pulsée
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 2026
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: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland Reference number
ii
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Samples . 2
5.1 General .2
5.2 Calibration samples .2
5.2.1 General .2
5.2.2 Samples for moisture-content calibration .2
5.2.3 Samples for oil-content calibration .2
6 Apparatus . 2
7 Sampling . 3
8 Preparation of test sample . 3
9 Calibration procedure . 3
9.1 General .3
9.2 Calibration procedure for the determination of water content .4
9.2.1 Procedure A: Three calibration samples (minimum) with known water contents .4
9.2.2 Procedure B: One calibration sample with known water content .5
9.3 Calibration procedure for the determination of oil content .6
9.3.1 Procedure A: Three calibration samples (minimum) with known oil contents .6
9.3.2 Procedure B: One calibration sample with known oil content.6
10 Procedure for measuring the test sample . 7
10.1 General .7
10.2 Requirements for the test room and conditioning of the test sample.7
10.3 Test portion .7
10.4 Determination .8
10.4.1 General case .8
10.4.2 Rapeseeds, linseeds and sunflower seeds having a water content greater than
a mass fraction of 10 % and soya beans having a water content greater than a
mass fraction of 14 % .8
11 Expression of the results . 9
12 Precision . 9
12.1 Interlaboratory tests .9
12.2 Repeatability .9
12.3 Reproducibility .9
13 Test report . 9
Annex A (informative) Results of interlaboratory tests .11
Annex B (informative) Results of test to compare different equipment .13
Bibliography .15

iii
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
2, Oleaginous seeds and fruits and oilseed meals, 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 third edition cancels and replaces the second edition (ISO 10565:1998), which has been technically
revised.
The main changes are as follows:
— the scope has been clarified;
— additional information has been added to the protocol;
— the results of a test to compare different equipment have been added.
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
FINAL DRAFT International Standard ISO/FDIS 10565:2026(en)
Oilseeds — Simultaneous determination of oil and water
contents — Method using pulsed nuclear magnetic resonance
spectrometry
1 Scope
This document specifies a rapid method for the determination of the oil and water contents in oilseeds using
pulsed nuclear magnetic resonance (NMR).
It is applicable to rapeseeds, linseeds and sunflower seeds with a water content less than 10 % and soya
beans with a water content less than 14 %. For seeds with higher water contents, drying is necessary before
the water and oil content can be determined by pulsed NMR.
NOTE 1 This method has been tested with rapeseeds, soya beans, linseeds and sunflower seeds. This does not,
however, preclude its applicability to other commercial seeds whose oil is liquid at the temperature of measurement.
NOTE 2 The reproducibility values obtained are generally higher than those obtained by the reference methods (see
ISO 659 and ISO 665) because they depend on the variability between the instruments and on that existing between
the calibrations, which depends on the measurement accuracy of the reference methods.
NOTE 3 The results of the comparison test between different magnets and different volumes of seed samples (see
Annex B) are in coherence with the results of the interlaboratory test (see Annex A).
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 659, Oilseeds — Determination of oil content (Reference method)
ISO 664, Oilseeds — Reduction of laboratory sample to test sample
ISO 665, Oilseeds — Determination of moisture and volatile matter content
3 Terms and definitions
No terms and definitions are listed in this document.
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/
4 Principle
Insertion of the test sample into the magnetic field of a pulsed NMR spectrometer.
Application of an alternating electromagnetic field in the form of an intense 90° radiofrequency (RF) pulse
which excites all the hydrogen nuclei. Recording of the free induction decay (FID) following the 90° pulse.
The maximum amplitude of this signal is proportional to the total number of protons from the water and oil
phases of the sample.
Application of the second RF pulse, a so-called “180° pulse”, to produce a spin-echo signal when only the
signal from the oil phase contributes to the FID.
NOTE 1 The maximum amplitude of this echo signal is proportional to the oil content. It varies with the sample
temperature following a complex law. An increase in temperature decreases the measured value of the echo.
Calculation of the difference between the two amplitudes, which is proportional to the water content.
Automatic conversion of the measured signals, after suitable calibration of the apparatus, into percentages
of oil or water.
NOTE 2 Simultaneous indications of the oil and water contents can be given by some spectrometers equipped with
a minicomputer and a specific program.
5 Samples
5.1 General
Transfer the calibration and test samples to the test room at least 60 min before the determination to allow
them to reach equilibrium temperature.
For rapeseeds, linseeds and sunflower seeds with a water content greater than a mass fraction of 10 % and
soybeans with a water content greater than a mass fraction of 14 %, refer to 10.4.2. In this case, the NMR
spin-echo method does not give a correct value because the excess water (free water) contributes, together
with the oil, to the spin-echo signal. This excess water shall therefore be removed by drying to a moisture
level of below a mass fraction of 10 % for all seeds.
5.2 Calibration samples
5.2.1 General
Samples of oilseeds shall be of the same species as the test samples and of similar fatty acid compositions
(e.g. for the analysis of rapeseeds which are rich in erucic acid or sunflower seeds which are rich in oleic
acid).
Calibration samples shall be homogeneous and free from impurities. A definition of impurities is given in
[1]
ISO 658 .
5.2.2 Samples for moisture-content calibration
The water content of seeds can vary depending on storage conditions. Water content shall therefore be
determined in accordance with ISO 665 just prior to calibration.
5.2.3 Samples for oil-content calibration
Oil content shall be determined using the reference method specified in ISO 659.
6 Apparatus
Usual laboratory apparatus and, in particular, the following shall be used.
6.1 Pulsed low-resolution NMR spectrometer, suitable for measurement of the oil content and water
content of oilseeds, and meeting the precision requirements of 12.2 and 12.3.
The instrument’s parameters shall be in accordance with the instructions/specifications from the
manufacturer.
For all calibration and measurement operations, follow the user’s manual.

The temperature of the test room shall be maintained in accordance with the instructions of the
manufacturer. Ensure that all operations during sample preconditioning before measurement (see 5.1),
calibration and measurement are carried out under the same conditions and, in particular, at the same
temperature (±2 °C). Therefore, the test room should be temperature controlled.
NOTE Usual range for the test room temperature is between 17 °C and 28 °C.
CAUTION — Remove metallic objects from the proximity of the NMR spectrometer.
6.2 Sample tubes, made of glass, suitable for use with the NMR spectrometer.
Follow the manufacturers’ instructions for suitable sample tube filling heights and the ranges of mass
variation recommended for different seeds.
For a filling height of 30 mm with tubes of diameter 40 mm (which is equivalent to a volume of 40 ml), the
following ranges of masses are recommended:
— whole rapeseeds and linseeds: 22 g to 25 g;
— whole sunflower seeds: 14 g to 17 g;
— whole soya beans: 21 g to 24 g.
For medium seeds (sunflower, soya and safflower), the tubes should be filled to at least 40 ml in order to
guarantee the representativeness of the sample to be analysed.
6.3 Analytical balance, electronic, capable of weighing to an accuracy of ± 0,01 g.
This equipment may be linked to the NMR spectrometer so that the sample mass is recorded directly by the
NMR or linked to a minicomputer (see NOTE 2 in Clause 4).
6.4 Drying oven, capable of being maintained at 103 °C ± 2 °C.
6.5 Dishes, made of glass or metal, of diameter 7 cm to 10 cm, and provided with lids.
7 Sampling
Sampling is not part of the method specified in this document. A recommended sampling method is given in
[3]
ISO 21294 .
It is important that the laboratory receive a sample which is truly representative and has not been damaged
or changed during transport or storage.
8 Preparation of test sample
Prepare the test sample in accordance with ISO 664.
Remove from the prepared test sample all metallic objects (e.g. staples, needles). Whole seeds shall be
homogeneous and, as far as possible, free from impurities.
9 Calibration procedure
9.1 General
9.1.1 To develop calibration, a minimum of three calibration samples shall be used, although more than
three samples should be used. These samples can either be from three or more independent calibration
samples, each with a different and known water and oil content (procedure A) or from a single calibration
...

ISO/TC 34/SC 2
Secretariat: AFNOR
Date: 2026-05-1806-09
Oilseeds — Simultaneous determination of oil and water contents —
Method using pulsed nuclear magnetic resonance spectrometry
Graines oléagineuses — Détermination simultanée de la teneur en huile et en eau — Méthode par
spectrométrie par résonance magnétique nucléaire pulsée
FDIS stage
TThhiis s drdraafftt i is s susubbmmiitttteed d ttoo aa ppaarraallellel l vvoottee i inn IISSOO,, CCEEN.N.

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
Foreword . iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Samples . 2
5.1 General . 2
5.2 Calibration samples . 2
6 Apparatus . 2
7 Sampling . 3
8 Preparation of test sample . 3
9 Calibration procedure . 4
9.1 General . 4
9.2 Calibration procedure for the determination of water content . 5
9.3 Calibration procedure for the determination of oil content . 6
10 Procedure for measuring the test sample . 7
10.1 General . 7
10.2 Requirements for the test room and conditioning of the test sample . 7
10.3 Test portion . 7
10.4 Determination . 7
11 Expression of the results . 8
12 Precision . 9
12.1 Interlaboratory tests . 9
12.2 Repeatability . 9
12.3 Reproducibility . 9
13 Test report . 9
Annex A (informative) Results of interlaboratory tests . 11
Annex B (informative) Results of test to compare different equipment . 13
Bibliography . 15

iii
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 2,
Oleaginous seeds and fruits and oilseed meals, 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 third edition cancels and replaces the second edition (ISO 10565:1998), which has been technically
revised.
The main changes are as follows:
— the scope has been clarified;
— additional information has been added to the protocol;
— Thethe results of a test to compare different equipment have been added.
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
Oilseeds — Simultaneous determination of oil and water contents —
Method using pulsed nuclear magnetic resonance spectrometry
1 Scope
This document specifies a rapid method for the determination of the oil and water contents in oilseeds using
pulsed nuclear magnetic resonance (NMR).
It is applicable to rapeseeds, linseeds and sunflower seeds with a water content less than 10 %, and soya beans
with a water content less than 14 %. For seeds with higher water contents, drying is necessary before the
water and oil content can be determined by pulsed NMR.
NOTE 1 This method has been tested with rapeseeds, soya beans, linseeds and sunflower seeds. This does not,
however, preclude its applicability to other commercial seeds whose oil is liquid at the temperature of measurement.
NOTE 2 The reproducibility values obtained are generally higher than those obtained by the reference methods (see
ISO 659 and ISO 665) because they depend on the variability between the instruments and on that existing between the
calibrations, which depends on the measurement accuracy of the reference methods.
NOTE 3 The results of the comparison test carrying out frombetween different magnets and different volumes of seed
samples (see Annex B) are in coherence with the results of the interlaboratory test (see Annex A).It’s concluding that this
method is applicable on different magnets NMR.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 659, Oilseeds — Determination of oil content (Reference method)
ISO 664, Oilseeds — Reduction of laboratory sample to test sample
ISO 665, Oilseeds — Determination of moisture and volatile matter content
3 Terms and definitions
No terms and definitions are listed in this document.
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/
4 Principle
Insertion of the test sample into the magnetic field of a pulsed NMR spectrometer.
Application of an alternating electromagnetic field in the form of an intense 90° radiofrequency (RF) pulse
which excites all the hydrogen nuclei. Recording of the free induction decay (FID) following the 90° pulse. The
maximum amplitude of this signal is proportional to the total number of protons from the water and oil phases
of the sample.
Application of the second RF pulse, a so-called “180° pulse”, to produce a spin-echo signal when only the signal
from the oil phase contributes to the FID.
NOTE 1 The maximum amplitude of this echo signal is proportional to the oil content. It varies with the sample
temperature following a complex law. An increase in temperature decreases the measured value of the echo.
Calculation of the difference between the two amplitudes, which is proportional to the water content.
Automatic conversion of the measured signals, after suitable calibration of the apparatus, into percentages of
oil or water.
NOTE 2 Simultaneous indications of the oil and water contents can be given by some spectrometers equipped with a
minicomputer and a specific program.
5 Samples
5.1 General
Transfer the calibration and test samples to the test room at least 60 min before the determination to allow
them to reach equilibrium temperature.
For rapeseeds, linseeds, and sunflower seeds with a water content greater than a mass fraction of 10%, % and
soybeans with a water content greater than a mass fraction of 14 %, refer to 10.4.2. In this case, the NMR spin-
echo method does not give a correct value because the excess water (free water) contributes, together with
the oil, to the spin-echo signal. This excess water shall therefore be removed by drying to a moisture level of
below a mass fraction of 10 % for all seeds.
5.2 Calibration samples
5.2.1 General
Samples of oilseeds shall be of the same species as the test samples and of similar fatty acid compositions (for
instancee.g. for the analysis of rapeseeds which are rich in erucic acid, or sunflower seeds which are rich in
oleic acid).
Calibration samples shall be homogeneous and free from impurities. A definition of impurities is given in
[1]
ISO 658 .
5.2.2 Samples for moisture-content calibration
The water content of seeds can vary depending on storage conditions. Water content shall therefore be
determined in accordance with ISO 665 just prior to calibration.
5.2.3 Samples for oil-content calibration
Oil content shall be determined using the reference method specified in ISO 659.
6 Apparatus
Usual laboratory apparatus and, in particular, the following shall be used.
6.1 Pulsed low-resolution NMR spectrometer, suitable for measurement of the oil content and water
content of oilseeds, and meeting the precision requirements of 12.2 and 12.3.
The instrument’s parameters shall be in accordance with the instructions/specifications from the
manufacturer.
For all calibration and measurement operations, follow the user’s manual.
The temperature of the test room shall be maintained in accordance with the instructions of the manufacturer.
Ensure that all operations during sample preconditioning before measurement (see 5.1), calibration and
measurement are carried out under the same conditions and, in particular, at the same temperature (±2 °C).
Therefore, it is recommended that the test room should be temperature controlled.
NOTE Usual range for the test room temperature is between 17 °C and 28 °C.
CAUTION — Remove metallic objects from the proximity of the NMR spectrometer.
6.2 Sample tubes, made of glass, suitable for use with the NMR spectrometer.
Follow the manufacturers’ instructions for suitable sample tube filling heights and the ranges of mass
variation recommended for different seeds.
For a filling height of 30 mm with tubes of diameter 40 mm (which is equivalent to a volume of 40 ml), the
following ranges of masses are recommended:
— whole rapeseeds and linseeds: 22 g to 25 g;
— whole sunflower seeds: 14 g to 17 g;
— whole soya beans: 21 g to 24 g.
For medium seeds (sunflower, soya and safflower), the tubes should be filled to at least 40 ml, in order to
guarantee the representativeness of the sample to be analysed.
6.3 Analytical balance, electronic, capable of weighing to an accuracy of ± 0,01 g.
This equipment may be linked to the NMR spectrometer so that the sample mass is recorded directly by the
NMR or linked to a minicomputer (see NOTE 2 in Clause 4).
6.4 Drying oven, capable of being maintained at 103 °C ± 2 °C.
6.5 Dishes, made of glass or metal, of diameter 7 cm to 10 cm, and provided with lids.
7 Sampling
Sampling is not part of the method specified in this document. A recommended sampling method is given in
[3][2]
ISO 21294 .
It is important that the laboratory receive a sample which is truly representative and has not been damaged
or changed during transport or storage.
8 Preparation of test sample
Prepare the test sample in accordance with ISO 664.
Remove from the prepared test sample all metallic objects (e.g. staples, needles). Whole seeds shall be
homogeneous and, as far as possible, free from impurities.
9 Calibration procedure
9.1 General
9.1.1 To develop calibration, a minimum of three calibration samples shall be used, although more than
three samples should be used. These samples arecan either be from three or more independent calibration
samples, each with a different and known water and oil content (procedure A), or from a single calibration
sample with a known water and oil content from which 3three or more calibration samples are simulated
(procedure B). The water content and oil content of each calibration sample should be determined
independently using respectively the reference methods specified in ISO 665 and ISO 659., respectively.
9.1.2 9Use the set-up parameters of the NMR spectrometer (6.1) recommended by the manufacturer and
optimize them by preliminary tests (e.g. amplification set for the highest signal).
9.1.3 Enter the parameters for the measurements (pulse sequence, attenuation, etc.) of the oil or water
content (as applicable) into the NMR spectrometer, following the manufacturer’s recommendations, and
specify a code number under which the calibration curve is to be stored.
The scan number shall be between 16 and 32 scans. To optimize the scan number for specific equipment and
a specific matrix, the manufacturer can be contacted.
9.1.4 Set the apparatus to the calibration mode.
9.1.5 Introduce a portion of the first calibration sample into a tared sample tube (6.2) up to the optimum
height specified by the manufacturer. Transfer the value of the sample mass from the balance to the NMR
spectrometer.
At least two determinations on test portions taken from the same test sample should be carried out.
NOTE A manual feed of the mass at the calibration sample into the NMR spectrometer is also possible.
9.1.6 Enter, as applicable, the value of either the water content (as a percentage by mass) or the oil content
(as a percentage by mass) into the spectrometer.
9.1.7 Introduce the sample tube containing the first calibration sample into the measuring head. Record
automatically or manually the water or oil values thus obtained.
9.1.8 Repeat steps 9.1.5 to 9.1.7 for the two (or more) other calibration samples.
9.1.9 Calculate automatically or manually the calibration parameters of the calibration curve using the
results obtained in 9.1.7 and 9.1.8.
The correlation coefficient shall normally be greater than 0,95. If this is not the case, check the values obtained
using the reference methods specified in ISO 659 and ISO 665, or repeat the calibration procedure using three
(or more) other calibration samples.
9.1.10 Store the calibration curve under the code number chosen in step 9.1.3.
9.1.11 It is recommended to check theThe prediction error of the NMR calibra
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