DIN EN ISO 6887-1-2017 Microbiology of the food chain - Preparation of test samples initial suspension and decimal dilutions for microbiological examination - Part 1 General rules .pdf

1、July 2017 English price group 15No 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 07.100.30!%h8S“2692148www.din.deDIN

2、 EN ISO 6887-1Microbiology of the food chain Preparation of test samples, initial suspension and decimal dilutions for microbiological examination Part 1: General rules for the preparation of the initial suspension and decimal dilutions (ISO 68871:2017);English version EN ISO 68871:2017,English tran

3、slation of DIN EN ISO 6887-1:2017-07Mikrobiologie der Lebensmittelkette Vorbereitung von Untersuchungsproben und Herstellung von Erstverdnnungen und von Dezimalverdnnungen fr mikrobiologische Untersuchungen Teil 1: Allgemeine Regeln fr die Herstellung von Erstverdnnungen und Dezimalverdnnungen (ISO

4、68871:2017);Englische Fassung EN ISO 68871:2017,Englische bersetzung von DIN EN ISO 6887-1:2017-07Microbiologie de la chane alimentaire Prparation des chantillons, de la suspension mre et des dilutions dcimales en vue de lexamen microbiologique Partie 1: Rgles gnrales pour la prparation de la suspen

5、sion mre et des dilutions dcimales (ISO 68871:2017);Version anglaise EN ISO 68871:2017,Traduction anglaise de DIN EN ISO 6887-1:2017-07SupersedesDIN EN ISO 68871:199904www.beuth.deDocument comprises 35 pagesDTranslation by DIN-Sprachendienst.In case of doubt, the German-language original shall be co

6、nsidered authoritative.07.17 DIN EN ISO 6887-1:2017-07 2 A comma is used as the decimal marker. National foreword This document (EN ISO 6887-1:2017) has been prepared by Technical Committee ISO/TC 34 “Food products” (Secretariat: AFNOR, France) in collaboration with Technical Committee CEN/TC 275 “F

7、ood analysis Horizontal methods” (Secretariat: DIN, Germany). The responsible German body involved in its preparation was DIN-Normenausschuss Lebensmittel und landwirtschaftliche Produkte (DIN Standards Committee Food and Agricultural Products), Working Committee NA 057-01-06 AA “Microbiology of the

8、 food chain”. The DIN Standards corresponding to the International Standards referred to in this document are as follows: ISO 6579-1 DIN EN ISO 6579-1 ISO 7218 DIN EN ISO 7218 ISO 11133 DIN EN ISO 11133 ISO 16140-2 DIN EN ISO 16140-2 ISO 18593 DIN EN ISO 18593 ISO/TS 17728 DIN CEN ISO/TS 17728 Amend

9、ments This standard differs from DIN EN ISO 6887-1:1999-04 as follows: a) the standard has been completely revised and extended. The standard has been revised in the context of revising the standards DIN EN ISO 6887-2:2004-01, DIN EN ISO 6887-3:2003-12 and DIN EN ISO 6887-4:2012-01; b) Clause 8 “Pre

10、paration of samples” has been extended and requirements from the standards DIN EN ISO 6887, Parts 2 to 4 have been included; c) Clause 9 “Specific procedures” includes new specifications regarding pooling and compositing samples for qualitative analysis; d) this standard includes the new Annexes A t

11、o D; e) the document has been editorially revised. Previous editions DIN EN ISO 6887-1: 1999-04 DIN EN ISO 6887-1:2017-07 3 National Annex NA (informative) Bibliography DIN CEN ISO/TS 17728, Microbiology of the food chain Sampling techniques for microbiological analysis of food and feed samples DIN

12、EN ISO 6579-1, Microbiology of food and Microbiology of the food chain Horizontal method for the detection, enumeration and serotyping of Salmonella Part 1: Detection of Salmonella spp. DIN EN ISO 7218, Microbiology of food and animal feeding stuffs General requirements and guidance for microbiologi

13、cal examinations DIN EN ISO 11133, Microbiology of food, animal feed and water Preparation, production, storage and performance testing of culture media DIN EN ISO 16140-2, Microbiology of food and animal feed Method validation Part 2: Protocol for the validation of alternative (proprietary) methods

14、 against a reference method DIN EN ISO 18593, Microbiology of food and animal feeding stuffs Horizontal methods for sampling techniques from surfaces using contact plates and swabs DIN EN ISO 6887-1:2017-07 4 This page is intentionally blank EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 6

15、887-1 April 2017 ICS 07.100.30 Supersedes EN ISO 6887-1:1999 English Version Microbiology of the food chain Preparation of test samples, initial suspension and decimal dilutions for microbiological examination Part 1: General rules for the preparation of the initial suspension and decimal dilutions

16、(ISO 6887-1:2017) Microbiologie de la chane alimentaire Prparation des chantillons, de la suspension mre et des dilutions dcimales en vue de lexamen microbiologique Partie 1: Rgles gnrales pour la prparation de la suspension mre et des dilutions dcimales (ISO 6887-1:2017) Mikrobiologie der Lebensmit

17、telkette Vorbereitung von Untersuchungsproben und Herstellung von Erstverdnnungen und von Dezimalverdnnungen fr mikrobiologische Untersuchungen Teil 1: Allgemeine Regeln fr die Herstellung von Erstverdnnungen und Dezimalverdnnungen (ISO 6887-1:2017) This European Standard was approved by CEN on 14 J

18、anuary 2017. 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

19、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 CEN member into its own language and notified to th

20、e 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 Macedonia, France, Germany, Greece, Hungary, Iceland, Ire

21、land, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Manag

22、ement 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 Members. Ref. No. EN ISO 6887-1:2017 E EN ISO 6887-1:2017 (E) 2 Contents Page European foreword . 3 Foreword 4 Introduction 5 1 Scope 6 2 Normative ref

23、erences 6 3 Terms and definitions . 6 4 Principle . 8 5 Diluents . 8 5.1 Basic materials . 8 5.2 Diluents for general use 8 5.2.1 Peptone salt solution . 8 5.2.2 Buffered peptone water 9 5.2.3 Double-strength buffered peptone water 9 5.3 Diluents for special purposes . 9 5.4 Distribution and sterili

24、zation of the diluent . 9 5.5 Performance testing for diluents . 10 6 Apparatus 10 7 Sampling 11 8 Preparation of samples 11 8.1 General . 11 8.2 Frozen products 12 8.2.1 General . 12 8.2.2 Small samples defrosted before testing . 12 8.2.3 Large pieces or blocks sampled while frozen 12 8.3 Hard and

25、dry products . 13 8.4 Dehydrated and other low-moisture products . 13 8.5 Liquid and non-viscous products . 13 8.6 Acidic products . 13 8.7 High-fat (over 20 %) foods . 14 8.8 Multi-component products . 14 8.9 Packaged products. 14 8.10 Surface samples (swabs and other devices) . 15 9 Specific proce

26、dures . 15 9.1 Test portion and initial suspension (primary dilution) . 15 9.2 Duration of the procedure 16 9.3 Pooling and compositing procedures for qualitative tests . 16 10 Further dilutions 16 10.1 Decimal dilution series 16 10.2 Other dilution series . 17 Annex A (informative) Illustrations of

27、 pooling and compositing procedures 18 Annex B (informative) Method for sampling frozen test pieces or blocks . 23 Annex C (informative) Data showing reliability of test results according to size of test portions . 25 Annex D (informative) Verification protocol for pooling samples for qualitative te

28、sts 28 Bibliography . 31 DIN EN ISO 6887-1:2017-07 EN ISO 6887-1:2017 (E) European foreword This document (EN ISO 6887-1:2017) has been prepared by Technical Committee ISO/TC 34 “Food products” in collaboration with Technical Committee CEN/TC 275 “Food analysis Horizontal methods” the secretariat of

29、 which is held by DIN. 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 October 2017, and conflicting national standards shall be withdrawn at the latest by October 2017. Attention is drawn to the

30、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 6887-1:1999. According to the CEN-CENELEC Internal Regulations, the national sta

31、ndards organizations of the following 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,

32、Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 6887-1:2017 has been approved by CEN as EN ISO 6887-1:2017 without any modification. 3 DIN EN ISO 6887-1:2017-0

33、7 ForewordISO (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

34、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 matter

35、s 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 documents should be noted. This docum

36、ent was drafted in accordance 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

37、such patent rights. Details 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 an

38、d does not constitute an endorsement.For an explanation on 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 following URL:

39、www .iso .org/ iso/ foreword .html.This document was prepared by Technical Committee ISO/TC 34, Food products, Subcommittee SC 9, Microbiology.This second edition cancels and replaces the first edition (ISO 6887-1:1999), which has been technically revised.A list of parts in the ISO 6887 series can b

40、e found on the ISO website.EN ISO 6887-1:2017 (E) 4 DIN EN ISO 6887-1:2017-07 IntroductionBecause of the large variety of food and animal feed products, this horizontal method might not be appropriate in every detail for certain products. In this case, different methods which are specific to these p

41、roducts can be used if absolutely necessary for justified technical reasons.When this document is next reviewed, account will be taken of all information then available regarding the extent to which this horizontal method has been followed and the reasons for deviations from this method in the case

42、of particular products.The harmonization of test methods cannot be immediate and for certain groups of products, International Standards and/or national standards may already exist that do not comply with this horizontal method. It is hoped that when such standards are reviewed, they will be changed

43、 to comply with this document so that eventually, the only remaining departures from this horizontal method will be those necessary for well-established technical reasons.This document defines the general rules for the preparation of samples, initial suspensions and subsequent dilutions for microbio

44、logical examination. The remaining parts of ISO 6887 give specific rules for the preparation of samples and initial suspensions, each covering the variety of food and feed products and environmental samples to which ISO 6887 applies.For a number of products, it is necessary to take special precautio

45、ns, especially when preparing the initial suspension, because of the physical state of the product (such as dry products, highly viscous products) or the presence of inhibitory substances (such as spices, high salt content) or the acidity, etc. These are covered in general terms in this document.Any

46、 special diluents or practices required for particular products or microorganisms in specific standard methods take priority over the general rules listed in the ISO 6887 series. These can include the following: specific rehydration procedures for foods of low water activity to minimize osmotic shoc

47、k; the use of adequate temperatures to aid suspension of cocoa, gelatine, milk powder, etc.; resuscitation procedures for the improved recovery of stressed microorganisms resulting from food processing and storage; homogenization procedures and duration specific to certain products (e.g. cereals) an

48、d/or to certain determinations (e.g. yeasts and moulds).EN ISO 6887-1:2017 (E) 5 DIN EN ISO 6887-1:2017-07 WARNING The use of this document may involve hazardous materials, operations and equipment. It is the responsibility of the user of this document to establish appropriate safety and health prac

49、tices and to determine the applicability of regulatory limitations before use.1 ScopeThis document defines general rules for the aerobic preparation of the initial suspension and of dilutions for microbiological examinations of products intended for human or animal consumption.This document is applicable to the general case and other parts apply to specific groups of products as mentioned in the foreword. S