1、July 2017 English price group 10No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 67.200.10!%guU“2688250www.din.deDIN
2、 EN ISO 6320Animal and vegetable fats and oils Determination of refractive index (ISO 6320:2017);English version EN ISO 6320:2017,English translation of DIN EN ISO 6320:2017-07Tierische und pflanzliche Fette und le Bestimmung des Brechungsindex (ISO 6320:2017);Englische Fassung EN ISO 6320:2017,Engl
3、ische bersetzung von DIN EN ISO 6320:2017-07Corps gras dorigines animale et vgtale Dtermination de lindice de rfraction (ISO 6320:2017);Version anglaise EN ISO 6320:2017,Traduction anglaise de DIN EN ISO 6320:2017-07SupersedesDIN EN ISO 6320:200006 andDIN EN ISO 6320 Corrigendum 1:200607www.beuth.de
4、Document comprises 14 pagesDTranslation by DIN-Sprachendienst.In case of doubt, the German-language original shall be considered authoritative.06.17 DIN EN ISO 6320:2017-07 2 A comma is used as the decimal marker. National foreword This document (EN ISO 6320:2017) has been prepared by Technical Comm
5、ittee ISO/TC 34 “Food products” (Secretariat: AFNOR, France) in collaboration with Technical Committee CEN/TC 307 “Oil seeds, vegetable and animal fats and oils and their by-products Methods of sampling and analysis” (Secretariat: AFNOR, France). The responsible German bodies involved in its prepara
6、tion were DIN-Normenausschuss Lebensmittel und landwirtschaftliche Produkte (DIN Standards Committee Food and Agricultural Products) and the Deutsche Gesellschaft fr Fettwissenschaft (German Fat Research Society), Joint Working Committee NA 057-05-05 AA “Joint committee of DIN and DGF for the analys
7、is of fats, oils and products thereof, related and primary products”. The DIN Standards corresponding to the International Standards referred to in this document are as follows: ISO 661 DIN EN ISO 661 ISO 5555 DIN EN ISO 5555 ISO 5725-1 DIN ISO 5725-1 ISO 5725-2 DIN ISO 5725-2 Amendments This standa
8、rd differs from DIN EN ISO 6320:2000-06 and DIN EN ISO 6320 Corrigendum 1:2006-07 as follows: a) milk and milk products (or fat coming from milk and milk products) are now excluded from the scope of the standard; b) in Clause 6 “Apparatus”, a note stating that modern digital refractometers may be us
9、ed has been included; c) the contents of Corrigendum 1:2006 (Annex A) has been adopted; d) the standard has been editorially revised and brought in line with the current rules of presentation. Previous editions DIN EN ISO 6320: 2000-06 DIN EN ISO 6320 Corrigendum 1: 2006-07 DIN EN ISO 6320:2017-07 3
10、 National Annex NA (informative) Bibliography DIN EN ISO 661, Animal and vegetable fats and oils Preparation of test sample DIN EN ISO 5555, Animal and vegetable fats and oils Sampling DIN ISO 5725-1, Accuracy (trueness and precision) of measurement methods and results Part 1: General principles and
11、 definitions General principles and definitions DIN ISO 5725-2, Accuracy (trueness and precision) of measurement methods and results Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method DIN EN ISO 6320:2017-07 4 This page is intentionally b
12、lank EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 6320 March 2017 ICS 67.200.10 Supersedes EN ISO 6320:2000English Version Animal and vegetable fats and oils - Determination of refractive index (ISO 6320:2017) Corps gras dorigines animale et vgtale - Dtermination de lindice de rfraction(
13、ISO 6320:2017) Tierische und pflanzliche Fette und le - Bestimmung des Brechungsindex (ISO 6320:2017) This European Standard was approved by CEN on 9 March 2017. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
14、 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-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, F
15、rench, 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-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgar
16、ia, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerla
17、nd, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2017 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Me
18、mbers. Ref. No. EN ISO 6320:2017 EEuropean foreword .31 Scope . 52 Normative reference . 53 Terms and definitions . 54 Principle 55 Reagents 66 Apparatus . 67 Sampling 68 Preparation of test sample . 69 Procedure. 69.1 Calibration of the instrument . 79.2 Determination . 710 Calculation 711 Precisio
19、n . 811.1 Interlaboratory test. 811.2 Repeatability . 811.3 Reproducibility . 812 Test report . 8Annex A (normative) Results of an interlaboratory test 9Bibliography . 10Contents PageDIN EN ISO 6320:2017-07 EN ISO 6320:2017 (E)2Foreword . 4European foreword This document (EN ISO 6320:2017) has been
20、prepared by Technical Committee ISO/TC 34 “Food products” in collaboration with Technical Committee CEN/TC 307 “Oilseeds, vegetable and animal fats and oils and their by-products - Methods of sampling and analysis” the secretariat of which is held by AFNOR. This European Standard shall be given the
21、status of a national standard, either by publication of an identical text or by endorsement, at the latest by September 2017, and conflicting national standards shall be withdrawn at the latest by September 2017. Attention is drawn to the possibility that some of the elements of this document may be
22、 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 6320:2000, EN ISO 6320:2000/AC 2006. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following
23、 countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norwa
24、y, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 6320:2017 has been approved by CEN as EN ISO 6320:2017 without any modification. DIN EN ISO 6320:2017-07 EN ISO 6320:2017 (E)3 ForewordISO (the Inte
25、rnational 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
26、 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 s
27、tandardization.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 documents should be noted. This document was drafted in acco
28、rdance with the editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).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. Det
29、ails of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www .iso .org/ patents).Any trade name used in this document is information given for the convenience of users and does not constitute a
30、n endorsement.For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the fol
31、lowing URL: www .iso .org/ iso/ foreword .html.This document was prepared by Technical Committee ISO/TC 34, Food products, Subcommittee SC 11, Animal and vegetable fats and oils.This fifth edition cancels and replaces the fourth edition (ISO 6320:2000), of which it constitutes a minor revision by th
32、e addition of an exclusion for fat coming from milk and milk products.DIN EN ISO 6320:2017-07 EN ISO 6320:2017 (E)4 1 ScopeThis document specifies a method for the determination of the refractive index of animal and vegetable fats and oils.Milk and milk products (or fat coming from milk and milk pro
33、ducts) are excluded from the scope of this document.2 Normative referenceThe 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 la
34、test edition of the referenced document (including any amendments) applies.ISO 661, Animal and vegetable fats and oils Preparation of test sampleISO 5725-1, Accuracy (trueness and precision) of measurement methods and results Part 1: General principles and definitionISO 5725-2, Accuracy (trueness an
35、d precision) of measurement methods and results Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.ISO and IEC maintain terminological data
36、bases for use in standardization at the following addresses: IEC Electropedia: available at h t t p :/ www .electropedia .org/ ISO Online browsing platform: available at h t t p :/ www .iso .org/ obp3.1refractive index (of a medium)ratio of the velocity of light of a definite wavelength in a vacuum
37、to its velocity in the mediumNote 1 to entry: In practice, the velocity of light in air is used in place of that in a vacuum and, unless otherwise specified, the selected wavelength is the mean wavelength of the sodium D lines (589,6 nm).Note 2 to entry: The refractive index of a given substance var
38、ies with the wavelength of the incident light and with temperature. The notation used is ntD, where t is the temperature in degrees Celsius.4 PrincipleBy means of a suitable refractometer, the refractive index of a liquid sample is measured at a specified temperature.DIN EN ISO 6320:2017-07 EN ISO 6
39、320:2017 (E)5 5 ReagentsUse only reagents of recognized analytical grade and distilled or demineralized water or water of equivalent purity.5.1 Ethyl laurate, of quality suitable for refractometry, and of known refractive index.5.2 Hexane, or other suitable solvents, such as light petroleum, acetone
40、 or toluene, for cleaning the prism of the refractometer.6 ApparatusUsual laboratory equipment and, in particular, the following.Modern digital refractometers may be used. The manufacturers instructions should be followed in this case.6.1 Refractometer, for example of the Abb type, suitable for meas
41、urements of refractive index to within 0,000 1 over the range nD= 1,300 to nD= 1,700.6.2 Light source: sodium vapour lampWhite light can also be used if the refractometer is fitted with an achromatic compensation system.6.3 Glass plate, of known refractive index.6.4 Water bath, thermostatically cont
42、rolled, with a circulation pump, and capable of being maintained to the nearest 0,1 C.6.5 Water bath, capable of being maintained at the temperature at which the measurements are to be made (in the case of solid samples).7 SamplingIt is important that the laboratory receive a sample which is truly r
43、epresentative and has not been damaged or changed during transportation or storage.Sampling is not part of the method specified in this document. A recommended sampling method is given in ISO 5555.8 Preparation of test samplePrepare the test sample in accordance with ISO 661.The refractive index sha
44、ll be determined on dried and filtered fats and oils.In the case of a solid sample, transfer the sample prepared in accordance with ISO 661 to a suitable container and place it in the water bath (6.5), set at the temperature at which the measurements are to be made. Allow sufficient time for the tem
45、perature of the sample to stabilize.9 ProcedureNOTE If it is required to check whether the repeatability requirement (see 11.2) is met, carry out two single determinations in accordance with 9.1 and 9.2.DIN EN ISO 6320:2017-07 EN ISO 6320:2017 (E)6 9.1 Calibration of the instrumentVerify the calibra
46、tion of the refractometer (6.1) by measuring the refractive index of the glass plate (6.3) in accordance with the manufacturers instructions, or by measuring the refractive index of the ethyl laurate (5.1).9.2 DeterminationMeasure the refractive index of the test sample at one of the following tempe
47、ratures:a) 20 C for fats and oils that are completely liquid at this temperature;b) 40 C for fats and oils that are completely melted at this temperature but not at 20 C;c) 50 C for fats and oils that are completely melted at this temperature but not at 40 C;d) 60 C for fats and oils that are comple
48、tely melted at this temperature but not at 50 C;e) 80 C or above for other fats and oils, for example completely hardened fats or waxes.Maintain the temperature of the prism of the refractometer at the required constant value by circulating through the instrument water from the water bath (6.4).Monitor the temperature of the water issuing from the refractometer using a suitable precision thermometer. Immediately before the meas
