© ISO 2017 Microbiology of the food chain — Preparation of test samples, initial suspension and decimal dilutions for microbiological examination — Part 2 Specific rules for the preparation of meat an[.]
INTERNATIONAL STANDARD ISO 6887-2 Second edition 2017-0 Microbiology of the food chain — Preparation of test samples, initial suspension and decimal dilutions for microbiological examination — Part 2: Specific rules for the preparation o f meat and meat products Microbiologie de la chne alimentaire — Préparation des échantillons, de la suspension mère et des dilutions décimales en vue de l’examen microbiologique — Partie 2: Règles spécifiques pour la préparation des viandes et produits carnés Reference number ISO 6887-2:2017(E) © ISO 2017 ISO 6887-2:2017(E) COPYRIGHT PROTECTED DOCUMENT © ISO 2017, Published in Switzerland All rights reserved Unless otherwise specified, no part o f this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission Permission can be requested from either ISO at the address below or ISO’s member body in the country o f the requester ISO copyright o ffice Ch de Blandonnet • CP 401 CH-1214 Vernier, Geneva, Switzerland Tel +41 22 749 01 11 Fax +41 22 749 09 47 copyright@iso.org www.iso.org ii © ISO 2017 – All rights reserved ISO 6887-2 : 01 7(E) Page Contents iv Scope Normative references Terms and definitions Principle Diluents Apparatus Sampling and sample types 7.1 General f f Preparation of samples 8.1 General 8.2 Purpose of testing 8.3 General case for acidic products 8.4 High-fat products (over 20 % of total mass as fat) Specific procedures f ff f 9.1.2 Blocks, large pieces, meat cuts 9.1.3 Slices or pieces of meat or cooked meat 9.1.4 Fragments, shavings and trimmings 9.1.6 Cooked meats 9.1.7 Chicken and duck feet 9.2 Procedure for pre-packed products 9.3 Procedure for non-frozen products 9.3.1 Sample preparation from depth within the test material 9.3.2 Sample preparation from the surface of meat (excision/destructive method) 9.3.3 Sample preparation from individual slices 9.3.4 Sample preparation of carcass samples 9.4 Sample preparation for frozen products f 9.6 Sample preparation of surface samples (swabs and other devices) 10 Further dilutions Annex A (informative) Template for the delineation of a surface sample area Bibliography Foreword 7.2 General typ es o s amp les s ent to the lab o rato ry 7.3 S p ecific typ es o s amp les s ent to the lab o rato ry 9.1 I nitial p rep aratio n o 9.1 the di erent typ es o s amp les Lab o rato ry s amp le with a mas s equal to o r les s than g 5 9.1 M eat p ro ducts in “s kins ” (s aus ages ) 5 5 5 9.5 S amp le p rep aratio n © ISO 2017 – All rights reserved o r dried and p artially dehydrated meats and meat extracts iii ISO 6887-2:2017(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies) The work o f 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 o f electrotechnical standardization The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part In particular the different approval criteria needed for the di fferent types o f ISO documents should be noted This document was dra fted in accordance with the editorial rules of the ISO/IEC Directives, Part (see www.iso org/directives) Attention is drawn to the possibility that some o f the elements o f this document may be the subject o f patent rights ISO shall not be held responsible for identi fying any or all such patent rights Details o f any patent rights identified during the development o f 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 in formation given for the convenience o f users and does not constitute an endorsement For an explanation on the meaning o f ISO specific terms and expressions related to formity assessment, as well as information about ISO’s adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html The committee responsible for this document is ISO/TC 34, Food products, Subcommittee SC 9, Microbiology This second edition cancels and replaces the first edition (ISO 6887-2:2003), which has been technically revised A list of parts in the ISO 6887 series can be found on the ISO website iv © ISO 2017 – All rights reserved INTERNATIONAL STANDARD ISO 6887-2:2017(E) Microbiology of the food chain — Preparation of test samples, initial suspension and decimal dilutions for microbiological examination — Part 2: Specific rules for the preparation o f meat and meat products 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 practices and to determine the applicability of regulatory limitations before use Scope This c u ment s p e c i fie s ru le s for the prep aration o f me at a nd me at pro duc t s a mple s a nd thei r suspension for microbiological examination when the samples require different preparation from the f f suspension and dilutions for microbiological examination This document excludes preparation of samples for both enumeration and detection test methods me tho d s de s crib e d i n I S O 8 7-1 I S O 8 7-1 defi ne s the genera l ru le s or the prep a ration o the i n itia l where prep aration de tai l s are s p e c i fie d i n the relevant I nternationa l Standard s T h i s c u ment i s appl ic able to the their products: — refrigerated or frozen; — cured or fermented; — minced or comminuted; — meat preparations; — fol lowi ng fre s h, raw and pro ce s s e d me ats , p ou ltr y and ga me a nd me ch an ic a l ly s ep arate d me at; — cooked meats; — d rie d and s moke d me ats at variou s de gre e s o f dehyd ration; — concentrated meat extracts; — excision and swab samples from carcasses This document excludes the sampling of carcasses (see ISO 17604) and preparation of samples from the pri mar y pro duc tion s tage (s e e I S O 8 7- 6) © ISO 2017 – All rights reserved ISO 6887-2 : 01 7(E) T he Normative references fol lowi ng c u ments are re ferre d to i n the te xt i n s uch a way that s ome or a l l o f thei r content s titute s re qu i rements o f th i s c u ment For date d re ference s , on ly the e d ition c ite d appl ie s For undate d re ference s , the l ate s t e d ition o f the re ference d c u ment (i nclud i ng a ny amend ments) appl ie s ISO 6887-1, 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 ISO 7218, Microbiology of food and animal feeding stuffs — General requirements and guidance for microbiological examinations ISO 17604, Microbiology of the food chain — Carcass sampling for microbiological analysis Microbiology of food and animal feeding stuffs — Horizontal methods for sampling techniques from surfaces using contact plates and swabs I S O 59 , Terms and definitions ISO 6887-1 f ISO and IEC maintain terminological databases for use in standardization at the following addresses: — IEC Electropedia: available at http://www.electropedia org/ — ISO Online browsing platform: available at http://www.iso org/obp For the purp o s e s o f th i s cu ment, the term s and defi nition s given i n and the ol lowi ng apply block large piece meat cut sample whose composition and dimensions (surface and thickness, but thickness in particular) allow a s a mple to b e ta ken at dep th u nder s ati s fac tor y s teri le cond ition s 3.2 shaving sample from frozen meat resulting from a cut surface sample 3.3 fragment s a mple ta ken at dep th i n s ide the te s t pie ce by ele c tric d ri l l or a h and- d ri l l slice c ut o f me at with approxi mately p ara l lel s ide s up to s evera l centi me tre s th ick 3.5 trimming meat scrap that has been cut from carcasses or larger pieces of meat Principle The general principles for sample preparation and subsequent steps are detailed in ISO 6887-1 while I S O 8 7-2 de s crib e s s p e ci fic s ample prep aration for me at and me at pro duc ts © ISO 2017 – All rights reserved ISO 6887-2 : 01 7(E) Diluents Diluents for general use and special purposes are described in ISO 6887-1 and there are no additional s p e ci fic re qu i rements for me at a nd me at pro duc ts Apparatus Us ua l m ic robiolo gic a l lab orator y particular, the following e qu ipment for genera l 6.1 Equipment for cauterization of meat surfaces 6.2 Template for surface sampling use (I S O 8 7-1 and ISO 8) and, in , e.g portable gas blowtorch , metallic or plastic frame of appropriate dimensions enabling the delineatio n o f the s ur face to b e s amp led, s terilized by auto claving o r immers io n in % (vo lume fractio n) alco ho l and flaming An example of a template or frame is shown in Annex A, but other suitable tools are available As f sporulated microorganisms s ome s p ore s m ight s u r vive fla m i ng , a pre - s teri l i z e d me ta l template i s re com mende d when te s ti ng 7.1 or Sampling and sample types General C a rr y out s a mpl i ng i n accordance with the s p e c i fic s ta ndard appropri ate to the pro duc t concerne d or s e e I S O/ T S 17 I f a s p e ci fic s tanda rd i s no t ava i l able, it i s re com mende d th at agre ement b e re ache d on th i s s ubj e c t by the p ar tie s concerne d 7.2 General types of samples sent to the laboratory M e tho d s for h and l i ng the genera l typ e s o f s ample s that may b e s ubm itte d for te s ti ng , s uch a s fro zen, hard a nd d r y, l iquid and non-vi s cou s pro duc ts , and mu lti- comp onent pro duc ts are de tai le d i n I S O 8 7-1 as the s e a re appl ic able to ma ny typ e s o f 7.3 fo o d and fe e d Specific types o f samples sent to the laboratory M e at a nd me at-b as e d pro duc ts may i nclude any o f the — — — — — — fol lowi ng typ e s: units of meat or meat-based products, prepared or processed and of different dimensions; cuts of meat taken from larger units of meat; primal cuts of meat taken from carcasses; shavings or fragments taken from frozen blocks; offal from various species; oriental delicacies such as chicken and duck feet Ti s s ue s , s wab s or o ther typ e s o f s a mple s col le c te d u s i ng non- de s truc tive me tho d s (s e e I S O 176 4) may a l s o b e s ent to the lab orator y T he phys ic a l s tate o f the s ample s re ceive d may va r y accord i ng to the fol lowi ng fac tors: a) temperature, for products that are — non-frozen, or © ISO 2017 – All rights reserved ISO 6887-2 : 01 7(E) b) — frozen or deep-frozen (see ISO 7218); a w), for products that are — untreated, or — intermediate moisture meat products in which microbial growth is inhibited as a result of the a w) water ac tivity ( re duce d water ac tivity ( Preparation of samples 8.1 General All preparations and manipulations shall be carried out using aseptic techniques with sterile equipment (ISO 7218) 8.2 Purpose of testing General details are given in ISO 7218 The purpose of microbiological testing of meats includes detection and/or enumeration of from — m icrobi a l flora — s u r face m icrobia l flora, or — m icrobi a l flora from s a mp le s ta ken at dep th , the enti re s a mple (s u r face and dep th) Preparation of samples shall take into account the aim of the testing and the nature of the sample 8.3 General case for acidic products T he genera l c as e for prep aration o f ac id ic pro duc ts ( pH b e twe en , and 4, ) i s given i n I S O 8 7-1 and there are no add itiona l s p e c i fic re qui rements 8.4 for me at and me at pro duc ts High-fat products (over % of total mass as fat) The general case for preparation of high-fat products is given in ISO 6887-1 and there are no additional s p e c i fic re qui rements for me at a nd me at pro duc ts Specific procedures 9.1 Initial preparation of the different types of samples T h i s app l ie s on ly to s a mple s for the de te c tion or enu meration o f the to ta l m icrobia l flora the s u r face a nd dep th Us e s u fficient materia l from from b o th the lab orator y s ample to give a repre s entative te s t p or tion a s s p e c i fie d i n the te s t me tho d 9.1 Laboratory sample with a mass equal to or less than g Us e the whole lab orator y s a mple for prep a ration o f the i n iti a l s u s p en s ion i f the s ample mas s i s e qua l to or le s s than g 9.1 Blocks, large pieces, meat cuts For meat cuts, take the test portion at depth and/or a surface sample and prepare the initial suspension © ISO 2017 – All rights reserved ISO 6887-2:2017(E) 9.1.3 Slices or pieces of meat or cooked meat Take strips from the centre of the slices or pieces to prepare the initial suspension 9.1.4 Fragments, shavings and trimmings Homogenize these thoroughly be fore removing the test portion for preparation o f the initial suspension 9.1.5 Meat products in “skins” (sausages) If the skin is not intended for consumption, disinfect the cooked or raw sausages at the point of incision by wiping the sur face with 70 % (volume fraction) alcohol or by cauterizing using a blowtorch (6.1); pull to remove the skin with sterile forceps or tongs Slice the sausages and cut into small pieces before homogenizing Do not remove edible skins from raw sausages, but slice and homogenize including the skin 9.1.6 Cooked meats For packaged cooked meats, open the packaging in accordance with 9.2 and prepare test portions as for raw products 9.1.7 Chicken and duck feet Cut several units of chicken or duck feet (including all parts) with a pair of sterile scissors along the joints into smaller pieces Mix and weigh out the test portion in a tared sterile plastic bag Add nine times this mass o f an appropriate diluent (ISO 6887-1) and massage by hand for to to make the in 10 initial suspension 9.2 Procedure for pre-packed products For general instructions on sample preparation of packaged products, see ISO 6887-1 9.3 Procedure for non-frozen products 9.3.1 Sample preparation from depth within the test material Such test portions are used to examine only the deep tissue and sampling is carried out a fter cauterization of the surface Use scalpels and forceps to remove an appropriate area of skin from cuts of meat presented with skin on I f packaged, remove the sample aseptically and place on a sterile tray Remove a sur face layer mm to mm thick from the upper sur face to expose an area o f approximately cm by cm with a sterile scalpel or knife Cauterize this exposed surface using a blowtorch (6.1) until charring occurs Using a fresh sterile kni fe or scalpel, remove a layer about cm by cm and cm deep from below the charred area Using sterile forceps and scalpel, remove the required test portion from the exposed area and place it in a tared sterile container or plastic bag Weigh the test portion and add nine times this mass of an appropriate diluent (ISO 6887-1) to make the in 10 initial suspension 9.3.2 Sample preparation from the surface of meat (excision/destructive method) Samples are taken without cauterization of the exposed surface I f packaged, it may be necessary to remove the meat aseptically and place it on a sterile tray with the test surface uppermost Use a sterilized or disinfected template (6.2 ) and apply to the designated area (see Annex A) © ISO 2017 – All rights reserved ISO 6887-2 : 01 7(E) Using a sterile scalpel, cut along the inside edges of the template Then, using sterile forceps to lift the test portion, cut across the whole area to a depth of mm to mm and place the pieces in a tared sterile container or plastic bag Weigh the test portion and add nine times this mass of an appropriate diluent (ISO 6887-1) to make the in 10 initial suspension For such surface samples, the initial dilution should be recorded For example, from a sample from a surface diluted in a total volume of 100 ml of diluent, ml of this initial suspension represents 2 cm 0, cm 9.3 Sample preparation from individual slices Samples are taken without cauterization of the exposed surface I f p ackage d , it may b e ne ce s s a r y to remove the me at as ep tic a l ly and place it on a s teri le tray with the test surface uppermost Using a sterile scalpel and forceps, cut a strip cm wide along the centre of the greatest length Cut the strip into small pieces and place them into a tared sterile container or plastic bag Weigh the test portion and add nine times this mass of an appropriate diluent (ISO 6887-1) to make the in 10 initial suspension 9.3 Sample preparation of carcass samples P ro ce du re s 9.4 for s ampl i ng c arc a s s e s from fre s h ly s laughtere d a n i ma l s a re given i n I S O 176 Sample preparation for frozen products P ro ce du re s for h and l i ng s ma l l s ample s o f a l l typ e s b y de fro s ti ng b e fore s a mpl i ng and tho s e for s ampl i ng larger blo cks o f me at and me at pro duc ts without prel i m i nar y de fro s ti ng a re given i n I S O 8 7-1 9.5 Sample preparation for dried and partially dehydrated meats and meat extracts P ro ce du re s 9.6 for d rie d and p ar tia l ly dehyd rate d pro duc ts are gi ven i n I S O 8 7- Sample preparation of surface samples (swabs and other devices) For non-destructive carcass sampling using swabs or other devices, refer to ISO 17604 For genera l prep a ration a nd c a lc u lation i n s tr uc tion s for s wab s and o ther device s , re fer to I S O Further dilutions Prepare further dilutions in accordance with ISO 6887-1 © ISO 2017 – All rights reserved ISO 6887-2 : 01 7(E) Annex A (informative) Template for the delineation of a surface sample area T he device may b e made from materi a l s as fol lows: — frame: stainless-steel sheet with a thickness of 3/10 mm; — h and le: s tai n le s s - s te el c yl i nd ric a l s tem with a d i ame ter o f m m An example of a suitable template is shown in Figure A.1 © ISO 2017 – All rights reserved ISO 6887-2 : 01 7(E) Dimensions in millimetres Key brazing points Figure A.1 — Template for the delineation of a surface sample area © ISO 2017 – All rights reserved ISO 6887-2 : 01 7(E) Bibliography [1] [2] [3] ISO 6887-4, Microbiology of the food chain — Preparation of test samples, initial suspension and miscellaneous products ISO 6887-6, Microbiology of food and animal feed — Preparation of test samples, initial suspension and decimal dilutions for microbiological examination — Part 6: Specific rules for the preparation of samples taken at the primary production stage ISO/TS 17728, Microbiology of the food chain — Sampling techniques for microbiological analysis of food and feed samples decimal dilutions for microbiological examination — Part 4: Specific rules for the preparation o f © ISO 2017 – All rights reserved ISO 6887-2 : 01 7(E) ICS 07.100.30 Price based on pages © ISO 2017 – All rights reserved