ISO INTERNATIONAL STANDARD 18744 First edition 2016-04-01 Microbiology of the food chain Detection and enumeration of Cryptosporidium and Giardia in fresh leafy green vegetables and berry fruits Microbiologie de la chaine alimentaire Recherche et dénombrement de Cryptosporidium et Giardia dans les légumes verts frais a feuilles et les fruits a baies Reference number IS0 18744:2016(E) ISO International Organization for Standardization ZHEJIANG INST OF STANDARDIZATION C1 5956617 @IS02016 ted without license from IHS IS0 18744:2016(E) COPYRIGHTPROTECTEDDOCUMENT IS0 2016, Published in Switzerland All rights reserved. Unless otherwise specified, no part of 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 of the requester. ISO copyright office Ch. de Blandonnet 8 . 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 Internationai ibrg DrganizationforStandardization Licensee-ZHEJIANG INST OF STANDARDIZzRoISQ6 - All rights reserved networking permited without license from IHS IS0 18744:2016(E) Contents Page Foreword ..iv Introduction. ..V 1 Scope. ..1 2 Normative references ..1 3 Terms and definitions 4 Principle ..2 5 Reagents. .2 6 Apparatus 7 Sampling and transport .4 7.1 Sampling. ..4 7.2 Transport. .4 7.3 Receipt of samples .4 7.4 Storage .4 7.5 Preparation of test sample .4 8 Procedure .5 8.1 Removal of parasites from leafy green vegetables 5 8.2 Removal of parasites from berry fruits. .6 8.3 Immunomagnetic separation (IMS) 7 8.4 Sample staining 7 8.5 Microscopy .8 8.5.1 General comments .8 8.5.2 Examination of sample preparations using epifluorescence microscopy ..9 8.5.3 Examination of sample preparations using DIC microscopy. ..11 9 Quality control procedures ..12 9.1 General ..12 9.2 Inclusion and interpretation of controls. ..12 9.3 Equipment cleaning. ..13 10 Reporting of results ..13 10.1 Expression of results .13 10.2 Test report. ..13 Annex A (normative) Preparation of reagents ..15 Annex B (normative) Preparation of positive process control suspensions ..17 Annex C (informative) Percentage recoveries achieved by the methods ..19 Bibliography ..20 iii icensee=ZHEJIANG INST OF STANDARDIZATION C1 5956617 without license from IHS Not for Resale, 2016/6/2 08:55:35