1、English price group 12No 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!%XLI“2534138www.din.deDIN EN ISO 68
2、86Animal and vegetable fats and oils Determination of oxidative stability (accelerated oxidation test) (ISO 6886:2016);English version EN ISO 6886:2016,English translation of DIN EN ISO 6886:2016-07Tierische und pflanzliche Fette und le Bestimmung der Oxidationsstabilitt (beschleunigter Oxidationste
3、st) (ISO 6886:2016);Englische Fassung EN ISO 6886:2016,Englische bersetzung von DIN EN ISO 6886:2016-07Corps gras dorigines animale et vgtale Dtermination de la stabilit loxydation (essai doxydation acclr) (ISO 6886:2016);Version anglaise EN ISO 6886:2016,Traduction anglaise de DIN EN ISO 6886:2016-
4、07SupersedesDIN EN ISO 6886:2009-03www.beuth.deDocument comprises 19 pagesDTranslation by DIN-Sprachendienst.In case of doubt, the German-language original shall be considered authoritative.July 201607.16DIN EN ISO 6886:2016-07 2 A comma is used as the decimal marker. National foreword This document
5、 (EN ISO 6886:2016) has been prepared by Technical Committee 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)
6、. The responsible German bodies involved in its preparation 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 Committee NA 057-05-05 AA
7、 Gemeinschaftsausschuss fr die Analytik von Fetten, len, Fettprodukten, verwandten Stoffen und Rohstoffen. 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 5725-2 DIN ISO 5725-2 Amendments
8、This standard differs from DIN EN ISO 6886:2009-03 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) the standard has been editorially revised and brought in line with the current rules of presentation. Previous edit
9、ions DIN EN ISO 6886: 2009-03 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 5725-2, Accuracy (trueness and precision) of measurement methods and results P
10、art 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 6886 March 2016 ICS 67.200.10 Supersedes EN ISO 6886:2008 English Version Animal and vegetable fats and oils Determination of oxida
11、tive stability (accelerated oxidation test) (ISO 6886:2016) Corps gras dorigines animale et vgtale Dtermination de la stabilit loxydation (essai doxydation acclr) (ISO 6886:2016) Tierische und pflanzliche Fette und le Bestimmung der Oxidationsstabilitt (beschleunigter Oxidationstest) (ISO 6886:2016)
12、 This European Standard was approved by CEN on 13 February 2016. 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 r
13、eferences 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, French, German). A version in any other language made by translation under the responsibility of a
14、 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, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Maced
15、onia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EURO
16、PISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2016 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 6886:2016 E EN ISO 6886:2016 (E) Contents Page 2European foreword . 3 Foreword 4 1
17、 Scope 5 2 Normative references 5 3 Terms and definitions . 5 4 Principle . 5 5 Reagents and materials . 6 6 Apparatus . 6 7 Sampling . 7 8 Preparation of test sample and apparatus 9 8.1 Preparation of test sample 9 8.2 Preparation of apparatus . 9 8.2.1 Cleaning procedure 9 8.2.2 Determination of t
18、emperature correction 10 9 Procedure 10 10 Calculations 12 10.1 Manual calculation . 12 10.2 Automatic calculation . 12 11 Precision 12 11.1 Results of interlaboratory test 12 11.2 Repeatability 12 11.3 Reproducibility . 12 12 Test report 12 Annex A (informative) Summary of the method and examples o
19、f conductivity curves and the determination of induction time . 13 Annex B (informative) Results of an interlaboratory test 15 Bibliography . 17 DIN EN ISO 6886:2016-07 EN ISO 6886:2016 (E) 3DIN EN ISO 6886:2016-07 European foreword This document (EN ISO 6886:2016) has been prepared by Technical Com
20、mittee 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 analys is” the secretariat of which is held by AFNOR. This European Standard shall be given the status of a national stand
21、ard, either by publication of an identical text or by endorsement, at the latest by September 2016, and conflicting national standards shall be withdrawn at the latest by September 2016. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rig
22、hts. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN ISO 6886:2008. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Stan
23、dard: 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, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Sp
24、ain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 6886:2016 has been approved by CEN as EN ISO 6886:2016 without any modification. ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO me
25、mber 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, governme
26、ntal 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
27、 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 accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives). Attention
28、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. Details of any patent rights identified during the development of the document will be in the Introduction and/
29、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 an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity as
30、sessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary informationThe committee responsible for this document is ISO/TC 34, Food products, Subcommittee SC 11, Animal and vegetable fats and o
31、ils.This third edition cancels and replaces the second edition (ISO 6886:2006), of which it constitutes a minor revision.4EN ISO 6886:2016 (E) DIN EN ISO 6886:2016-07 1 ScopeThis International Standard specifies a method for the determination of the oxidative stability of fats and oils under extreme
32、 conditions that induce rapid oxidation: high temperature and high air flow. It does not allow determination of the stability of fats and oils at ambient temperatures, but it does allow a comparison of the efficacy of antioxidants added to fats and oils.The method is applicable to both virgin and re
33、fined animal and vegetable fats and oils. Milk and milk products (or fat coming from milk and milk products) are excluded from the scope of this International Standard.NOTE The presence of volatile fatty acids and volatile acidic oxidation products prevents accurate measurement.2 Normative reference
34、sThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 661
35、, Animal and vegetable fats and oils Preparation of test sample3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.3.1induction periodtime between the start of the measurement and the time when the formation of oxidation products rapidly begins to incr
36、ease3.2oxidative stabilityinduction period, expressed in hours, determined according to the procedure specified in this International StandardNote 1 to entry: A temperature of 100 C to 120 C is usually applied for the determination of oxidative stability. Depending on the oxidative stability of the
37、sample under test, or when an extrapolation of regression is required, the determination may be carried out at other temperatures. The optimal induction period is between 6 h to 24 h. A temperature increase or decrease of 10 C decreases or increases the induction period by a factor of approximately
38、2.3.3conductivityability of a material to conduct electric current4 PrincipleA stream of purified air is passed through the sample, which has been brought to a specified temperature. The gases released during the oxidation process, together with the air, are passed into a flask containing water that
39、 has been demineralized or distilled and contains an electrode for 5EN ISO 6886:2016 (E) DIN EN ISO 6886:2016-07 measuring the conductivity. The electrode is connected to a measuring and recording device. The end of the induction period is indicated when the conductivity begins to increase rapidly.
40、This accelerated increase is caused by the accumulation of volatile fatty acids produced during oxidation.5 Reagents and materialsUse only reagents of recognized analytical grade, and distilled or demineralized water.5.1 Molecular sieve, beads of approximately 1 mm diameter, pore size 0,3 nm, with m
41、oisture indicator.The molecular sieve should be dried in an oven set at 150 C and then cooled down to room temperature in a desiccator.5.2 Acetone.5.3 Alkaline cleaning solution, for laboratory glassware.5.4 Glycerol.5.5 Thermostable oil.6 ApparatusUsual laboratory equipment and, in particular, the
42、following.6.1 Appliance for the determination of oxidative stabilitySee Figures 1 and 2 for diagrammatic representations.NOTE An appliance for determining oxidative stability can be obtained commercially under the trade name Rancimat, from Metrohm AG, Herisau, Switzerland, or the OSI equipment from
43、Omnion Inc., USA.1)6.1.1 Air filter, comprising a tube fitted with filter paper at each end and filled with molecular sieve (5.1), connected to the suction end of a pump.6.1.2 Gas diaphragm pump, with an adjustable flow rate of 10 l/h, in combination with an apparatus to control the flow rate, manua
44、lly or automatically, with a maximum deviation of 1,0 l/h from the set value.NOTE For the OSI instrument, a pressure of 5,5 psi is equivalent to a flow of approximately 10 l/h.6.1.3 Aeration vessels of borosilicate glass (usually eight), connected to a sealing cap.The sealing cap shall be fitted wit
45、h a gas inlet and outlet tube. The cylindrical part of the vessel shall preferably be narrower by a few centimetres below the top in order to break up any emerging foam. An artificial foam blocker (e.g. glass ring) may also be used for this purpose.6.1.4 Closed measurement cells (usually eight), of
46、approximately 150 ml capacity, with a gas inlet tube extending to the bottom inside of the vessel.The cell shall be provided at the top with ventilation holes.1) Rancimat () and OSI (Omnion) (http:/ are examples of suitable equipment available commercially. This information is given for the convenie
47、nce of users of this document and does not constitute an endorsement by ISO of this equipment.6EN ISO 6886:2016 (E) DIN EN ISO 6886:2016-07 6.1.5 Electrodes (usually eight), for measuring conductivity with a measuring range of 0 S/cm to 300 S/cm, aligned with the dimensions of the measurement cell (
48、6.1.4).6.1.6 Measuring and recording apparatus, comprising an amplifier and a recorder for registering the measuring signal of each of the electrodes (6.1.5).NOTE A computer-controlled central processing unit is used with Rancimat and OSI (Omnion).6.1.7 Certified and calibrated contact thermometer,
49、graduated in 0,1 C, or Pt 100 element (platinum resistance thermometer) to measure the block temperature, with attachments for a control relay connection and an adjustable heating element; temperature range 0 C to 150 C.6.1.8 Heating block, made of cast aluminium, adjustable to a temperature of up to 150 C 0,1 C.The block shall be provided with holes (usually eight) for the aeration vessels (6.1.3), and an aperture for the contact thermometer (6.1.7).Alternatively, a heati
