Tài liệu Cip_microbiology and swab

Document owner Approved Release Date Issue Charlotta Steffner Anders Göransson 2009-03-17 2 6. Page 24 (32) Performance qualification When validating the cleaning process a worst case approach should be used, i.e. the equipment should be challenged with the product that is hardest to clean provided that the same cleaning program is used for all products. When evaluating the cleanliness special attention should be made to surfaces that are difficult to clean. A combination of methods may be used, e.g. both rinse water sampling as well as swabbing of surfaces. It is always recommended to make a visual inspection (can be refined by using UV light) to ensure that the process is acceptable prior to sampling for analytical evaluation. In addition to the visual inspection the proposal will be to use ATP/AMP as hygiene monitoring tool. Microbiological test methods like swabbing a surface or direct agar contact methods using general or selective media may also be used. The microbiological methods give an indication of the residual micro-organisms on the surface or in the rinse sample while ATP/AMP primarily indicates organic soil residues. Guidelines or standards for clean surfaces vary widely. Some suggested values can be seen in the enclosed table (C. Griffith, in Handbook of hygiene control in the food industry, 2005, Woodhead Publishing) Suggested values 80 cfu/cm2 5 cfu/cm2 0-10cfu/cm2 for aerobic colony count 0-1 cfu/cm2 Enterobacteriaceae <2,5cfu/cm2 <2,5 cfu/cm2 <500-RLUs * Date and source Herbert et al (1990) USDA(1994) EC Decision 2001. Meat (Hazard Analysis Critical Control Point) Regulations 2002 Mossel et al (1999) Griffith et al (2000) Applies to use of one specific ATP test/equipment combination (Griffith et al (2000) Swedish Food Agency (1998) Target 1 cfu/cm2 Maximum of 3 cfu/cm2 * This value is for one specific ATP test/equipment. It might be difficult to make general guidelines for a clean surface as different instruments/swabs differ. The following microbiological requirements are commonly used to determine the cleanliness of product surfaces: Total count Enterobacteriaceae Yeast and mould 2 < 100/dm < 1/dm2 < 100/dm2 The reference methods that have been recommended concerning culture media and incubation procedures are: © 2007 Tetra Pak Dairy & Beverage Systems AB Tetra Pak Internal Document owner Approved Release Date Issue Charlotta Steffner Anders Göransson 2009-03-17 2 Total count Enterobacteriaceae Yeast and mould Page 25 (32) ISO 4833 ISO 21528-2 ISO 7954 Examination method and expression of results should follow the principles laid down in ISO 7218/4833. Sampling techniques from surfaces using contact plates and swabs are described in ISO 18593:2004. ATP is often used in hygiene monitoring and the suggested value for cleanliness may differ depending on the instruments/swabs that are used as well as variations between different plants and different food. Therefore limiting values for ATP shall be determined in each individual plant. However typically after CIP in a dairy plant a value of < 100 RLU (based on Lumitester PD 10 – LuciPacW) is considered hygienically clean. Methodology: The instructions given by the different suppliers of ATP systems should be followed. Specific requirements from the customer with respect to test methods for performance qualification must of course be considered. © 2007 Tetra Pak Dairy & Beverage Systems AB Tetra Pak Internal