ISO INTERNATIONAL STANDARD 7218 Third edition 2007-08-15 Microbiology of food and animal feeding stuffs General requirements and guidance for microbiological examinations Microbiologie des aliments Exigences generales et recommendations Reference number ISO 7218:2007(E) @ ISO 2007 py IHS under lic ted without license from IHS Not for Resale ISO 7218:2007(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The IsO Central Secretariat accepts no liability in this area. Adobe is a trademark of Adobe Systems Incorporated. Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by IsO member bodies. In the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below COPYRIGHTPROTECTEDDOCUMENT @ISO2007 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, IsO's member body in the country of the requester. ISO copyright office Case postale 56. CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail [email protected] Web www.iso.org Published in Switzerland @ ISO 2007 - All rights reserved I without license from IHS Not for Resale ISO 7218:2007(E) Contents Page Foreword.. Introduction 1 Scope 2 3 Premises... 3.1 General, 3.2 Safety considerations.. 3.3 Laboratory design... 3.4 Laboratoryareas... 3.5 Layout and fittings of the premises. 3.6 Cleaning and disinfection .... 4 Staff. 4.1 4.2 Competence 4.3 Verification of on-going staff competence.. 4.4 Hygiene ...... 6 5 Apparatus and equipment .. 6 6 Preparation of glassware and other laboratory materials 28 6.1 Preparation ..... 6.2 Sterilization/decontamination... .28 6.3 Disposable equipment and materials ... 28 6.4 Storage of clean glassware and materials. 28 6.5 Management of sterile glassware and materials . 29 6.6 Use of decontamination and disinfection . 29 6.7 Waste management .. 29 6.8 Washing ... 30 7 8 Laboratory samples 8.1 Sampling.. .30 8.2 Transport. 31 8.3 Receipt.. 31 8.4 Storage. 8.5 Test portion 32 9 Examination... 9.1 Hygienic precautions during analysis 32 9.2 Preparation of initial suspension and dilutions 34 10 Enumeration.. 34 10.1 General...... 10.2 Enumeration using a solid medium ... 35 10.3 Calculation and expression of results obtained with solid media 37 10.4 Enumeration of yeasts and moulds..... 10.5 Enumeration using a liquid medium. 44 11 Detection method (qualitative method) . 11.1 General. 49 11.2 50 11.3 Measurement of uncertainty .50 Copyrght International Organizaionsandardizalonghts reserved ili ut license from IHS Not for Resale ISO 7218:2007(E) 12 Confirmatory methods.. 12.1 General. 12.2 Preparation of a pure culture .. ..50 12.3 Gram's stain (modified Hucker technique)..... ...50 12.4 Use of biochemical galleries for identification 12.5 Use of nucleic probes for identification ... ..52 12.6 Serological methods. 53 13 Test report ..53 14 Validation of microbiological methods. 14.1 Validation of reference methods ..... 14.2 Validation of alternative methods... 14.3 Validation of in-house methods.. 54 15 Quality assurance of results/quality control of performance. ..54 15.1 Internal quality control .. 54 15.2 Reference strains..... 15.3 External quality assessment (proficiency testing) . ..55 Annex A (informative) Properties of some disinfectants.. ..56 Annex B (normative) Determination of most probable number (MPN).. ..57 Bibliography ...64 CopyrightInternationalOrganizatinfor