1、BS EN ISO1737:2008ICS 67.100.10NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDEvaporated milk andsweetened condensedmilk Determinationof fat content Gravimetric method(Reference method)(ISO 1737:2008)This British Standardwas published under theauthority of the
2、StandardsPolicy and StrategyCommittee on 31 January2009 BSI 2009ISBN 978 0 580 63537 3Amendments/corrigenda issued since publicationDate CommentsBS EN ISO 1737:2008National forewordThis British Standard is the UK implementation of EN ISO 1737:2008. Itsupersedes BS EN ISO 1737:2000 which is withdrawn
3、.The UK participation in its preparation was entrusted to TechnicalCommittee AW/5, Chemical analysis of milk and milk products.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisionsof
4、a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunityfrom legal obligations.EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 1737October 2008ICS 67.100.10 Supersedes EN ISO 1737:1999 English VersionEvaporated milk and sweetened c
5、ondensed milk - Determinationof fat content - Gravimetric method (Reference method) (ISO1737:2008)Lait concentr sucr et non sucr - Dtermination de lateneur en matire grasse - Mthode gravimtrique(Mthode de rfrence) (ISO 1737:2008)Kondensmilch und gezuckerte Kondensmilch -Bestimmung des Fettgehaltes -
6、 Gravimetrisches Verfahren(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 EuropeanStandard the status of a national standard witho
7、ut any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards 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 ma
8、de by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France,
9、 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 STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUN
10、GManagement Centre: rue de Stassart, 36 B-1050 Brussels 2008 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 1737:2008: EBS EN ISO 1737:2008EN ISO 1737:2008 (E) 3 Foreword This document (EN ISO 1737:2008) has been prepared by Tec
11、hnical 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 publica
12、tion 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
13、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, Bulgar
14、ia, 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 o
15、f ISO 1737:2008 has been approved by CEN as a EN ISO 1737:2008 without any modification. BS EN ISO 1737:2008ISO 1737:2008(E) IDF 13:2008(E) ISO and IDF 2008 All rights reserved iiiContents Page Foreword iv Foreword. v 1 Scope 1 2 Normative references 1 3 Term and definitions .1 4 Principle1 5 Reagen
16、ts.2 6 Apparatus .2 7 Sampling.3 8 Preparation of test sample4 8.1 Evaporated milk .4 8.2 Sweetened condensed milk4 9 Procedure .4 9.1 Test portion 4 9.2 Blank tests4 9.3 Preparation of fat-collecting vessel.5 9.4 Determination.5 10 Calculation and expression of results.7 10.1 Calculation7 10.2 Expr
17、ession 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 BS E
18、N ISO 1737:2008ISO 1737:2008(E) IDF 13:2008(E) iv ISO and IDF 2008 All rights reservedForeword 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 th
19、rough 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 collab
20、orates 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 Stan
21、dards. 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
22、 this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 1737IDF 13 was prepared by Technical Committee ISO/TC 34, Food products, Subcommittee SC 5, Milk and milk products, and the International Dairy Federation (IDF). I
23、t is being published jointly by ISO and IDF. This fourth edition of ISO 1737IDF 13 cancels and replaces the third edition (ISO 1737:1999), of which it constitutes a minor revision. BS EN ISO 1737:2008ISO 1737:2008(E) IDF 13:2008(E) ISO and IDF 2008 All rights reserved vForeword IDF (the Internationa
24、l 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 repr
25、esented 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 Nation
26、al 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
27、 for identifying any or all such patent rights. ISO 1737IDF 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
28、-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 1737IDF 13 cancels and replaces IDF 13:1987, of which it constitutes a minor revision. BS EN ISO 1737:2008BS EN ISO 1737:2008INTERNATIONAL STANDA
29、RD ISO 1737:2008(E)IDF 13:2008(E) ISO and IDF 2008 All rights reserved 1Evaporated 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 Inter
30、national 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 Internation
31、al 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 th
32、is 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 3889IDF 219, Mil
33、k 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
34、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 remov
35、ed by distillation or evaporation. The mass of the substances extracted is determined. NOTE This is usually known as the Rse-Gottlieb principle. BS EN ISO 1737:2008ISO 1737:2008(E) IDF 13:2008(E) 2 ISO and IDF 2008 All rights reserved5 Reagents Use only reagents of recognized analytical grade, unles
36、s 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 NH3ofapproximately 25 % (20= 910 g
37、/l). 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 (C2H5OH), or ethanol denatured by methanol, containing a volume fraction of ethanol of at least 94 %. (See Clause A.5.) 5.3 Congo red solutio
38、n Dissolve 1 g of Congo red (C32H22N6Na2O6S2) in water in a 100 ml one-mark volumetric flask (6.14). Make 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 indica
39、tor solutions can be used provided that they do not affect the result of the determination. 5.4 Diethyl ether (C2H5OC2H5), free from peroxides (see Clause A.3), containing no more than 2 mg/kg of antioxidants, and complying with the requirements for the blank test (see 9.2.2, Clauses A.1 and A.4). W
40、ARNING 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 (CH3CH23CH3) with a boiling point of 36 C and complying with the requirem
41、ents for the blank test (see 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 invol
42、ves 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 readabilit
43、y of 0,1 mg. 6.2 Centrifuge, capable of holding the fat-extraction flasks or tubes (6.6) and capable of spinning at a rotational frequency of 500 min1to 600 min1to 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 recommend
44、ed (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. BS EN ISO 1737:2008ISO 1737:2008(E) IDF 13:2008(E) ISO and IDF 2008 All rig
45、hts reserved 36.4 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 betw
46、een 30 C and 40 C, and 40 C and 60 C. 6.6 Mojonnier-type fat-extraction flasks, as specified in ISO 3889IDF 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-extra
47、ction 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,
48、 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 boilin
49、g 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 suitab
