ISO INTERNATIONAL STANDARD 22964 First edition 2017-04 Microbiology of the food chain Horizontal method for the detection of Cronobacter spp. Microbiologie de la chaine alimentaire - Méthode horizontale pour la recherche de Cronobacter spp. Reference number ISO 22964:2017(E) International Organization for Standardization @ IS0 2017 ZHEJIANG INST OF STANDARDIZATION C1 5956617 vided by IHS under I Not for Resale, 2017/5/16 00:44:52 ted without license from IHS IS0 22964:2017(E) COPYRIGHTPROTECTEDDOCUMENT IS0 2017, 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. ISOcopyrightoffice Ch. de Blandonnet 8 . CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 [email protected] www.iso.org Internatinair PrganizationforStandardization ensee-ZHEJIANG INST.OF STANDARDIzARoISQa7 - All rights reserved Not for Resale, 2017/5/16 00:44:52 etworking permitted without license from IHS IS0 22964:2017(E) Contents Page Foreword ..iv Introduction. ..V 1 Scope. .1 2 Normative references ..1 3 Terms and definitions 4 Abbreviated terms ..2 5 Principle .2 5.1 Non-selective pre-enrichment in BPW .2 5.2 Enrichment in a selective medium (CSB) .2 5.3 Plating out and identification on chromogenic agar (CCI agar) .2 5.4 .2 Confirmation. 6 Culture media and reagents ..2 7 Equipment and consumables ..2 8 3 Sampling. 9 Preparation of test sample ..3 10 Procedure (as shown in Annex A) .3 10.1 Test portion. ..3 10.2 Pre-enrichment. 4 10.3 Enrichment .4 10.4 Isolation of presumptive Cronobacter spp .4 10.5 Confirmation .4 10.5.1 General .4 10.5.2 Purification of colonies ..5 10.5.3 Biochemicalconfirmation 10.6 Interpretation of biochemical results .6 11 Expression of results .6 12 Performance characteristics of the method. .1 12.1 Interlaboratory study .1 12.2 Sensitivity 7 12.3 Specificity 7 12.4 LOD50 7 13 Test report .7 Annex A (normative) Diagram of the test procedure ..8 Annex B (normative) Composition, preparation and performance testing of culture media andreagents .9 Annex C (informative) Distinction of Cronobacter spp.from other genera ..17 Annex D (informative) Method validation studies and performance characteristics ..19 Bibliography .22 iii withoutlicense from IHS