BS EN 15789 2021 Animal feeding stuffs methods of sampling and analysis detection and enumeration

BS EN 15789 2021 animal feeding stuffs methods of sampling and analysis detection and enumeration IMPORTANT — PLEASE NOTE The original version of BS EN 15789:2009, appended at the end of this document, should be considered the version of record for this publication. This is a tracked changes copy and uses the following colour coding:  Text example 1  — indicates added text (in green)  Text example 2  — indicates removed text (in red) — indicates added graphic figure or table — indicates removed graphic figure or table Introduction This methodmethodology has been developed to enumerate probiotic yeasts in additives, premixtures and feeding stuffs. To (Saccharomyces cerevisiae) used as feed additives to enable the European Commission to control proper labelling of animal feeding products (. It was compiled first during the EU project SMT4CT982235SMT4CT982235 “Methods for the official control of probiotics (microorganisms) used as animal feeds”) 1. It is based on ISO 7954, a pour plate method using extract dextrose chloramphenicol (CGYE) (alternatively oxytetracycline) agar, a selective agar for yeasts 1. This method is not selective for probiotic yeast but can be applied to enumerate yeast in feed assuming that the probiotic yeast is present in far higher numbers than any other yeastfeed additives” 1. The procedure has been validated for one commercially used Saccharomyces cerevisiae strain 2. As the method is not selective for this particular Saccharomyces cerevisiae strain, it can be assumed, that it can also be applied to enumerate other Saccharomyces cerevisiae strains in their respective dosage form in feed provided that the added yeast is present in far higher numbers than any other yeast. In addition or alternatively a spread plateThe method and a chromogenic1 agar can be used allowing an elective enumeration of the probiotichas not been validated for other yeast species for example (e.g.Saccharomyces cerevisiaeKluyveromyces marxianus, which forms distinct mauvepurple colonies. The presence of other yeasts will be identified on the elective agar by different colouration.). The application of both agars (CGYE and Chromagar® Candida) have been validated for four probiotic commercially used yeast strains, belonging toThis method is not applicable for the detection of any ubiquitous or pathogenic yeasts Saccharomyces cerevisiae, in premixturesfood and animal feeding stuffs 3.