SIST EN ISO 1737:2009

Evaporated milk and sweetened condensed milk - Determination of fat content - Gravimetric method (Reference method) (ISO 1737:2008)

This International Standard specifies the reference method for the determination of the fat content of all types of evaporat ed milk and sweetened condensed milk (liquid sweetened and uns weetened concentrated milk).

Kondensmilch und gezuckerte Kondensmilch - Bestimmung des Fettgehaltes - Gravimetrisches Verfahren (Referenzverfahren) (ISO 1737:2008)

Diese Internationale Norm legt das Referenzverfahren für die Bestimmung des Fettgehaltes aller Arten von Kondensmilch und gezuckerter Kondensmilch (flüssige gezuckerte und ungezuckerte Kondensmilch) fest.

Lait concentré sucré et non sucré - Détermination de la teneur en matière grasse - Méthode gravimétrique (Méthode de référence) (ISO 1737:2008)

L'ISO 1737|FIL 13:2008 spécifie la méthode de référence pour la détermination de la teneur en matière grasse de tous les types de lait concentré sucré et non sucré.

Zgoščeno mleko in sladkano kondenzirano mleko - Določevanje maščobe - Gravimetrijska metoda (Referenčna metoda) (ISO 1737:2008)

General Information

• Status: Published
• Publication Date: 05-Jan-2009
• ICS: 67.100.10 - Milk and processed milk products
• Technical Committee: KŽP - Agricultural food products
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 08-Dec-2008
• Due Date: 12-Feb-2009
• Completion Date: 06-Jan-2009
• Ref Project: EN ISO 1737:2008 - Evaporated milk and sweetened condensed milk - Determination of fat content - Gravimetric method (Reference method) (ISO 1737:2008)

Relations

• Replaces: SIST EN ISO 1737:2000 - Evaporated milk and sweetened condensed milk - Determination of fat content - Gravimetric method (Reference method) (ISO 1737:1999)
• Effective Date: 01-Feb-2009

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 1737:2009
01-februar-2009
1DGRPHãþD
SIST EN ISO 1737:2000
=JRãþHQRPOHNRLQVODGNDQRNRQGHQ]LUDQRPOHNR'RORþHYDQMHPDãþREH
*UDYLPHWULMVNDPHWRGD5HIHUHQþQDPHWRGD,62
Evaporated milk and sweetened condensed milk - Determination of fat content -
Gravimetric method (Reference method) (ISO 1737:2008)
Kondensmilch und gezuckerte Kondensmilch - Bestimmung des Fettgehaltes -
Gravimetrisches Verfahren (Referenzverfahren) (ISO 1737:2008)
Lait concentré sucré et non sucré - Détermination de la teneur en matière grasse -
Méthode gravimétrique (Méthode de référence) (ISO 1737:2008)
Ta slovenski standard je istoveten z: EN ISO 1737:2008
ICS:
67.100.10 0OHNRLQSUHGHODQLPOHþQL Milk and processed milk
SURL]YRGL products
SIST EN ISO 1737:2009 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 1737:2009

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SIST EN ISO 1737:2009
EUROPEAN STANDARD
EN ISO 1737
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2008
ICS 67.100.10 Supersedes EN ISO 1737:1999
English Version
Evaporated milk and sweetened condensed milk - Determination
of fat content - Gravimetric method (Reference method) (ISO
1737:2008)
Lait concentré sucré et non sucré - Détermination de la Kondensmilch und gezuckerte Kondensmilch -
teneur en matière grasse - Méthode gravimétrique Bestimmung des Fettgehaltes - Gravimetrisches Verfahren
(Méthode de référence) (ISO 1737:2008) (Referenzverfahren) (ISO 1737:2008)
This European Standard was approved by CEN on 14 October 2008.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2008 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 1737:2008: E
worldwide for CEN national Members.

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SIST EN ISO 1737:2009
EN ISO 1737:2008 (E)
Contents Page
Foreword.3

2

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SIST EN ISO 1737:2009
EN ISO 1737:2008 (E)
Foreword
This document (EN ISO 1737:2008) has been prepared by Technical Committee ISO/TC 34 "Agricultural food
products" in collaboration with Technical Committee CEN/TC 302 “Milk and milk products - Methods of
sampling and analysis” the secretariat of which is held by NEN.
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by April 2009, and conflicting national standards shall be withdrawn at the
latest by April 2009.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 1737:1999.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
Endorsement notice
The text of ISO 1737:2008 has been approved by CEN as a EN ISO 1737:2008 without any modification.

3

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SIST EN ISO 1737:2009

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SIST EN ISO 1737:2009


INTERNATIONAL ISO
STANDARD 1737
IDF
13
Fourth edition
2008-10-15


Evaporated milk and sweetened
condensed milk — Determination of fat
content — Gravimetric method
(Reference method)
Lait concentré sucré et non sucré — Détermination de la teneur en
matière grasse — Méthode gravimétrique (Méthode de référence)




Reference numbers
ISO 1737:2008(E)
IDF 13:2008(E)
©
ISO and IDF 2008

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SIST EN ISO 1737:2009
ISO 1737:2008(E)
IDF 13:2008(E)
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©  ISO and IDF 2008
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO or IDF at the respective
address below.
ISO copyright office International Dairy Federation
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Tel. + 41 22 749 01 11 Tel. + 32 2 733 98 88
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Published in Switzerland

ii © ISO and IDF 2008 – All rights reserved

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SIST EN ISO 1737:2009
ISO 1737:2008(E)
IDF 13:2008(E)
Contents Page
Foreword. iv
Foreword. v
1 Scope .1
2 Normative references .1
3 Term and definitions .1
4 Principle.1
5 Reagents.2
6 Apparatus .2
7 Sampling.3
8 Preparation of test sample.4
8.1 Evaporated milk .4
8.2 Sweetened condensed milk.4
9 Procedure .4
9.1 Test portion .4
9.2 Blank tests.4
9.3 Preparation of fat-collecting vessel.5
9.4 Determination.5
10 Calculation and expression of results.7
10.1 Calculation.7
10.2 Expression of results .8
11 Precision.8
11.1 Interlaboratory test .8
11.2 Repeatability.8
11.3 Reproducibility.8
12 Test report .9
Annex A (informative) Notes on procedures .10
Annex B (informative) Alternative procedure using fat-extraction tubes with siphon or wash-bottle
fittings .12
Bibliography .15

© ISO and IDF 2008 – All rights reserved iii

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SIST EN ISO 1737:2009
ISO 1737:2008(E)
IDF 13:2008(E)
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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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 any or all such patent rights.
ISO 1737⎪IDF 13 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.
This fourth edition of ISO 1737⎪IDF 13 cancels and replaces the third edition (ISO 1737:1999), of which it
constitutes a minor revision.
iv © ISO and IDF 2008 – All rights reserved

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SIST EN ISO 1737:2009
ISO 1737:2008(E)
IDF 13:2008(E)
Foreword
IDF (the International Dairy Federation) is a non-profit organization representing the dairy sector worldwide.
IDF membership comprises National Committees in every member country as well as regional dairy
associations having signed a formal agreement on cooperation with IDF. All members of IDF have the right to
be represented at the IDF Standing Committees carrying out the technical work. IDF collaborates with ISO in
the development of standard methods of analysis and sampling for milk and milk products.
Draft International Standards adopted by the Action Teams and Standing Committees are circulated to the
National Committees for voting. Publication as an International Standard requires approval by at least 50 % of
the IDF National Committees casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. IDF shall not be held responsible for identifying any or all such patent rights.
ISO 1737⎪IDF 13 was prepared by the International Dairy Federation (IDF) and Technical Committee
ISO/TC 34, Food products, Subcommittee SC 5, Milk and milk products. It is being published jointly by IDF
and ISO.
All work was carried out by the Joint ISO-IDF Action Team Fat of the Standing Committee on Main
components in milk under the aegis of its project leader, Mr G.J. Beutick (NL).
This edition of ISO 1737⎪IDF 13 cancels and replaces IDF 13:1987, of which it constitutes a minor revision.

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SIST EN ISO 1737:2009

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SIST EN ISO 1737:2009
ISO 1737:2008(E)
INTERNATIONAL STANDARD
IDF 13:2008(E)

Evaporated milk and sweetened condensed milk —
Determination of fat content — Gravimetric method (Reference
method)
WARNING — The use of this International Standard may involve hazardous materials, operations and
equipment. This International Standard does not purport to address all the safety problems associated
with its use. It is the responsibility of the user of this International Standard to establish safety and
health practices and determine the applicability of regulatory limitations prior to use.
1 Scope
This International Standard specifies the reference method for the determination of the fat content of all types
of evaporated milk and sweetened condensed milk (liquid sweetened and unsweetened concentrated milk).
2 Normative references
The following referenced documents are indispensable for the application 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 835, Laboratory glassware — Graduated pipettes
ISO 1042, Laboratory glassware — One-mark volumetric flasks
ISO 3889⎪IDF 219, Milk and milk products — Specification of Mojonnier-type fat extraction flasks
ISO 4788, Laboratory glassware — Graduated measuring cylinders
3 Term and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
fat content of evaporated milk and sweetened condensed milk
mass fraction of substances determined by the procedure specified in this International Standard
NOTE The fat content is expressed as a percentage mass fraction.
4 Principle
An ammoniacal ethanolic solution of a test portion is extracted with diethyl ether and light petroleum. The
solvents are removed by distillation or evaporation. The mass of the substances extracted is determined.
NOTE This is usually known as the Röse-Gottlieb principle.
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SIST EN ISO 1737:2009
ISO 1737:2008(E)
IDF 13:2008(E)
5 Reagents
Use only reagents of recognized analytical grade, unless otherwise specified, and distilled or demineralized
water or water of equivalent purity.
The reagents shall leave no appreciable residue when the determination is carried out by the method
specified (see 9.2.2).
5.1 Ammonia solution, containing a mass fraction of NH of approximately 25 % (ρ = 910 g/l).

3 20
NOTE If ammonia solution of this concentration is not available, a more concentrated solution of known concentration
may be used (see 9.4.2).
5.2 Ethanol (C H OH), or ethanol denatured by methanol, containing a volume fraction of ethanol of at
2 5
least 94 %. (See Clause A.5.)
5.3 Congo red solution
Dissolve 1 g of Congo red (C H N Na O S ) in water in a 100 ml one-mark volumetric flask (6.14). Make
32 22 6 2 6 2
up to the mark with water.
NOTE The use of this solution, which allows the interface between the solvent and aqueous layers to be seen more
clearly, is optional (see 9.4.3). Other aqueous indicator solutions can be used provided that they do not affect the result of
the determination.
5.4 Diethyl ether (C H OC H ), free from peroxides (see Clause A.3), containing no more than 2 mg/kg of
2 5 2 5
antioxidants, and complying with the requirements for the blank test (see 9.2.2, Clauses A.1 and A.4).
WARNING — The use of diethyl ether can lead to hazardous situations. Observe current safety
precautions for handling, use, and disposal.
5.5 Light petroleum, with any boiling range between 30 °C and 60 °C or, as equivalent, pentane
(CH [CH ] CH ) with a boiling point of 36 °C and complying with the requirements for the blank test (see
3 2 3 3
9.2.2, Clauses A.1 and A.4).
The use of pentane is recommended because of its higher purity and consistent quality.
5.6 Mixed solvent
Shortly before use, mix equal volumes of diethyl ether (5.4) and light petroleum (5.5).
6 Apparatus
WARNING — Since the determination involves the use of volatile flammable solvents, all electrical
apparatus employed shall comply with legislation relating to the hazards in using such solvents.
Usual laboratory equipment and, in particular, the following.
6.1 Analytical balance, capable of weighing to the nearest 1 mg, with a readability of 0,1 mg.
6.2 Centrifuge, capable of holding the fat-extraction flasks or tubes (6.6) and capable of spinning at a
−1 −1
rotational frequency of 500 min to 600 min to produce a radial acceleration of 80g to 90g at the outer end
of the flasks or tubes.
The use of the centrifuge is optional but recommended (see 9.4.6).
6.3 Distillation or evaporation apparatus, for distilling the solvents and ethanol from the boiling or conical
flasks, or evaporating from beakers and dishes (see 9.4.13) at a temperature not exceeding 100 °C.
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SIST EN ISO 1737:2009
ISO 1737:2008(E)
IDF 13:2008(E)
6.4 Drying oven, electrically heated, with ventilation port(s) fully open, capable of being maintained at a
temperature of 102 °C ± 2 °C throughout its working space.
The oven shall be fitted with a suitable thermometer.
6.5 Water baths, capable of being maintained at a temperature of between 30 °C and 40 °C, and 40 °C
and 60 °C.
6.6 Mojonnier-type fat-extraction flasks, as specified in ISO 3889⎪IDF 219.
NOTE It is also possible to use fat-extraction tubes with siphon or wash-bottle fittings, but then the procedure is
different. The alternative procedure is given in Annex B.
The fat-extraction flasks shall be provided with good quality cork bungs or stoppers of other material (e.g.
silicone rubber or polytetrafluoroethylene) unaffected by the reagents used. Cork bungs shall be extracted
with the diethyl ether (5.4), kept in water at a temperature of 60 °C or more for at least 15 min, and shall then
be allowed to cool in the water so that they are saturated when used.
6.7 Rack, for holding the fat-extraction flasks (or tubes) (6.6).
6.8 Wash bottle, suitable for use with the mixed solvent (5.6).
A plastics wash bottle shall not be used.
6.9 Fat-collecting vessels, such as boiling flasks (flat-bottomed), of capacities 125 ml to 250 ml, conical
flasks, of capacity 250 ml, or metal dishes.
If metal dishes are used, they shall be of stainless steel, flat-bottomed with a diameter of 80 mm to 100 mm
and a height of approximately 50 mm.
6.10 Boiling aids, fat-free, of non-porous porcelain or silicon carbide (optional when metal dishes are used).
6.11 Measuring cylinders, of capacities 5 ml and 25 ml, complying with the requirements of ISO 4788,
class A, or any other apparatus suitable for the product concerned.
6.12 Pipettes, graduated, of capacity 10 ml, complying with the requirements of ISO 835, class A.
6.13 Tongs, made of metal, for holding flasks, beakers or dishes.
6.14 Volumetric flask, one-mark, of capacity 100 ml, complying with the requirements of ISO 1042, class A.
7 Sampling
A representative sample should have been sent to the laboratory. It should not have been damaged or
changed during transport or storage.
Sampling is not part of the method specified in this International Standard. A recommended sampling method
[1]
is given in ISO 707⎪IDF 50 .
Store laboratory samples at a temperature between 2 °C and 6 °C from the time of sampling to the time of
commencing the procedure. Store samples in sealed cans unopened at a temperature below 20 °C.
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SIST EN ISO 1737:2009
ISO 1737:2008(E)
IDF 13:2008(E)
8 Preparation of test sample
8.1 Evaporated milk
Shake and invert the sample container. Open the sample container and pour the sample slowly into a second
sample container (provided with an airtight lid). Mix by repeated transfer, taking care to incorporate in the
sample any fat or other constituent adhering to the wall and ends of the first container. Finally, transfer the
product as completely as possible to the second container.
If necessary in the case of samples in sealed cans, condition the unopened container in the water bath (6.5)
maintained at a temperature of between 40 °C and 60 °C. Remove and shake the can vigorously every
15 min. After 2 h, remove the can and allow it to cool to room temperature.
Remove the lid entirely and thoroughly mix the sample by stirring with a spoon or spatula. (If fat separates, do
not test the sample.)
8.2 Sweetened condensed milk
Open the sample container and mix thoroughly with a spoon or spatula. Use an up-and-down rotary
movement in such a way that the top layers and the content of the lower corners of the container are moved
and mixed. Take care to incorporate in the sample any milk adhering to the wall and ends of the container.
Transfer the sample as completely as possible to a second sample container (provided with an airtight lid).
Close the second container.
If necessary, in the case of samples in sealed cans, condition the unopened can in the water bath (6.5) at a
temperature of between 30 °C and 40 °C. Open the can, scrape out all milk adhering to the interior of the can,
transfer to a dish large enough to permit stirring thoroughly and mix until the whole mass is homogeneous.
In the case of a sample in a collapsible tube, open the tube and transfer the contents to a jar. Then cut open
the tube and scrape out all material adhering to the interior and add to the contents of the jar.
9 Procedure
NOTE An alternative procedure using fat-extraction tubes with siphon or wash-bottle fittings (see Note to 6.6) is given
in Annex B.
9.1 Test portion
Mix the test sample (Clause 8), by stirring in the case of sweetened condensed milk, or by gently inverting the
bottle three or four times in the case of evaporated milk. Immediately weigh, to the nearest 1 mg, directly or by
difference, 4,000 g to 5,000 g of the test sample of evaporated milk, or 2,000 g to 2,500 g of the test sample of
sweetened condensed milk in a fat-extraction flask (6.6).
Transfer the test portion as completely as possible into the lower (small) bulb of the fat-extraction flask.
9.2 Blank tests
9.2.1 Blank test for method
Carry out a blank test simultaneously with the determination using the same procedure and same reagents,
but replacing the test portion by 10 ml of water (see Clause A.2).
When one blank sample is used for a batch of test samples of which the individual samples may not have
exactly the same conditions, ensure that the procedure for obtaining the value of the blank used in the
calculation of the result corresponds exactly to that of the individual test sample.
If the value obtained in the blank test regularly exceeds 1,0 mg, check the reagents if this has not been
recently done (9.2.2). Corrections of more than 2,5 mg should be mentioned in the test report.
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SIST EN ISO 1737:2009
ISO 1737:2008(E)
IDF 13:2008(E)
9.2.2 Blank test for reagents
To test the quality of the reagents, carry out a blank test as specified in 9.2.1. Additionally, use an empty fat-
collecting vessel, prepared as specified in 9.3, for mass control purposes. The reagents shall leave no residue
greater than 1,0 mg (see Clause A.1).
If the residue of the complete reagent blank test is greater than 1,0 mg, determine the residue of the solvents
separately by distilling 100 ml of the diethyl ether (5.4) and light petroleum (5.5), respectively. Use an empty
fat-collecting vessel, prepared for control purposes as in the preceding paragraph, to obtain the real mass of
residue which shall not exceed 1,0 mg.
Very occasionally, the solvents may contain volatile matter which is strongly retained in fat. If there are
indications of the presence of such substances, carry out blank tests on all the reagents and for each solvent
using a fat-collecting vessel with about 1 g of anhydrous butterfat. If necessary, redistil solvents in the
presence of 1 g of anhydrous butterfat per 100 ml of solvent. Use the solvents only shortly after the
redistillation.
Replace unsatisfactory reagents and solvents, or redistil solvents.
9.3 Preparation of fat-collecting vessel
Dry a fat-collecting vessel (6.9) with a few boiling aids (6.10) in the oven (6.4) maintained at 102 °C for 1 h.
NOTE 1 Boiling aids are desirable to promote gentle boiling during the subsequent removal of solvents, especially
when using glass fat-collecting vessels; their use is optional with metal dishes.
Protect the fat-collecting vessel from dust and allow it to cool to the temperature of the weighing room (glass
fat-collecting vessel for at least 1 h; metal dish for at least 30 min).
To avoid insufficient cooling or unduly long cooling times, the fat-collecting vessel should not be placed in a
desiccator.
Use tongs (6.13) to place the fat-collecting vessel on the balance. Weigh the fat-collecting vessel to the
nearest 1,0 mg.
NOTE 2 The use of tongs effectively avoids, in particular, inducing temperature variations.
9.4 Determination
9.4.1 Carry out the determination without delay.
Add water at a temperature of about 50 °C to the test portion in the fat-extraction flask (9.1) to obtain a total
volume of 10 ml to 11 ml. Use the water to wash the test portion on to the bottom of the flask. Shake gently
with slight warming at about 50 °C in the water bath (6.5) until the test portion is completely dispersed. Cool in
running water to room temperature.
9.4.2 Add 2 ml of ammonia solution (5.1) to the dispersed test portion in the fat-extraction flask (9.4.1), or
an equivalent volume of a more concentrated ammonia solution (see Note to 5.1). Mix thoroughly with the test
portion in the small bulb of the fat-extraction flask.
9.4.3 Add 10 ml of ethanol (5.2). Mix gently but thoroughly by allowing the contents of the fat-extraction
flask to flow backwards and forwards between the small and large bulb. Avoid bringing the liquid too near to
the neck of the flask. If desired, add 2 drops of the Congo red solution (5.3).
9.4.4 Add 25 ml of diethyl ether (5.4). Close the fat-extraction flask with a cork bung saturated with water or
with a stopper of other material wetted with water (6.6). Shake the flask vigorously, but not excessively, for
1 min to avoid the formation of persistent emul
...