This document specifies the enumeration of Clostridium (C.) perfringens by colony-count technique. This document is applicable to: \u2014 products intended for human consumption; \u2014 products for feeding animals; \u2014 environmental samples in the area of food and feed production and handling; \u2014 samples from the primary production stage. NOTE This method has been validated in an interlaboratory study for the following food categories: \u2014 ready-to-eat, ready-to-reheat meat products; \u2014 eggs and egg products (derivates); \u2014 processed fruits and vegetables; \u2014 infant formula and infant cereals; \u2014 multi-component foods or meal components. It has also been validated for the following other categories: \u2014 pet food and animal feed; \u2014 environmental samples (food or feed production). As this method has been validated for at least five food categories, this method is applicable for a broad range of food. For detailed information on the validation, see Clause 11 and Annex C. Since the method is not commonly used for samples in the primary production stage, this category was not included in the interlaboratory study. Therefore, no performance characteristics were obtained for this category. This horizontal method was originally developed for the examination of all samples belonging to the food chain. Based on the information available at the time of publication of this document, this method is considered to be fully suited to the examination of all samples belonging to the food chain. However, because of the large variety of products in the food chain, it is possible that this horizontal method is not appropriate in every detail for all products. Nevertheless, it is expected that the required modifications are minimized so that they do not result in a significant deviation from this horizontal method. This technique is suitable for, but not limited to, the enumeration of microorganisms in test samples with a minimum of 10 colonies counted on a plate. This corresponds to a level of contamination that is expected to be higher than 10 cfu\/ml for liquid samples or higher than 100 cfu\/g for solid samples.<\/p>\n
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| 72<\/td>\n | undefined <\/td>\n<\/tr>\n | ||||||
| 81<\/td>\n | 4.1 General 4.2 Preparation of dilutions 4.3 Enumeration 4.4 Confirmation <\/td>\n<\/tr>\n | ||||||
| 83<\/td>\n | 9.1 General 9.2 Test portion, initial suspension and dilutions 9.3 Heat treatment to select spores <\/td>\n<\/tr>\n | ||||||
| 84<\/td>\n | 9.4 Inoculation and incubation 9.5 Enumeration of typical colonies <\/td>\n<\/tr>\n | ||||||
| 85<\/td>\n | 9.6 Confirmation of C. perfringens 9.6.1 Selection of colonies for confirmation 9.6.2 Acid phosphatase test 9.6.3 Sulfite indole motility (SIM) agar test <\/td>\n<\/tr>\n | ||||||
| 86<\/td>\n | 9.6.4 Differentiation between human pathogenic and non-pathogenic C. perfringens strains (optional) 9.6.5 Interpretation 11.1 Interlaboratory study 11.2 Performance characteristics <\/td>\n<\/tr>\n<\/table>\n","protected":false},"excerpt":{"rendered":" Tracked Changes. Microbiology of the food chain. Horizontal method for the detection and enumeration of Clostridium spp. – Enumeration of Clostridium perfringens by colony-count technique<\/b><\/p>\n |