BS ISO BRITISH STANDARD 29981:2010 Milk products - Enumeration of presumptive bifidobacteria - Colony count technique at 37 oC ICS 67.100.01 BSi NO COPYING WITHOUT BSI PERMISSION EXCEPTAS PERMITTED BY COPYRIGHTLAW BritishStandards BSISO 29981:2010 National foreword This British Standard is the UK implementation of ISO 29981:2010. The UK participation in its preparation was entrusted to Technical Committee AW/5, Chemical analysis of milk and milk products. A list of organizations represented on this committee can be obtained on request to its secretary. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application Compliance with a British Standard cannot confer immunity from legal obligations. This British Standard Amendments/corrigendaissuedsincepublication was published under the authority of the Standards Policy and Strategy Date Comments Committee on 28 February 2010 BSI 2010 ISBN9780580618550 BS ISO 29981:2010 INTERNATIONAL ISO STANDARD 29981 IDF 220 First edition 2010-02-01 MilkproductsEnumerationof presumptive bifidobacteria Colony count technique at 37 °C Produitslaitiers-Denombrementdesbifidobacteriapresumés- Technique par comptage des colonies a 37c Referencenumbers ISO 29981:2010(E) IDF 220:2010(E) [So @ ISO and IDF 2010 BS ISO 29981:2010 ISO 29981:2010(E) IDF 220:2010(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. Neither the IsO Central Secretariat nor the IDF accepts any 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 and IDF national committees. In the unlikely event that a problem relating to it is found, please inform the ISO Central Secretariat at the address given below. COPYRIGHTPROTECTEDDOCUMENT @ISO andIDF2010 address below ISO copyright office International DairyFederation Casepostale56.CH-1211Geneva20 Diamant Building:Boulevard Auguste Reyers 80 ·B-1030 Brussels Tel. + 41 22 749 01 11 Tel. + 32 2 733 98 88 Fax + 41 22 749 09 47 Fax + 32 2 733 04 13 E-mail [email protected] E-mail [email protected] Web www.iso.org Web www.fi-idf.org Published in Switzerland ii @ ISO and IDF 2010 - All rights reserved BS ISO 29981:2010 ISO29981:2010(E) IDF220:2010(E) Contents Page Foreword .iv Foreword V 1 Scope.. 2 Normativereferences.. 3 Terms and definitions. 2 4 Principle... 2 5 Culture media, diluents and reagents 5.1 Basic materials ... 5.2 Diluent(s).... 5.3 Culture medium (TOS-MUPmedium) 6 Apparatus 5 7 Sampling... 5 8 Procedure 6 8.1 General. 6 8.2 Preparation of the test portionand primarydilution 8.3 8.4 Preparationofdecimaldilutions. 8.5 Inoculation 8.6 Duration oftheprocedure 8.7 8.8 Counting ofthe colonies. 8.9 Reading of the Petri dishes confirmation.. 9 Calculationandexpressionofresults 9.1 9.2 Expressionofresults.. 10 Precision..... .10 10.1 Interlaboratorytest. 10.2 Repeatability.... 10 10.3 Reproducibility .... 10 10.4 Precision data collectively definedfor dairy products 11 11 Knowledge of use of the method... 12 Test report. Annex A (informative) Interlaboratory trial -A'bifido'ring trial... @ ISO and IDF 2010 - All rights reserved ili BS ISO 29981:2010 ISO 29981:2010(E) IDF220:2010(E) Foreword Iso (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 International Electrotechnical Commission (IEC)on all matters of electrotechnical standardization adopted by the technical committ