BSI 21/30362561 DC:2021 Edition

This document specifies the enumeration of sulfite-reducing anaerobes and sulfite-reducing Clostridium spp. by the colony-count technique. This part of ISO 15213 is applicable to

• products intended for human consumption,

• products intended for animal feeding,

• environmental samples in the area of food and feed production, handling, and

• samples from the primary production stage.

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, use for the enumeration of microorganisms in test samples and is based on a minimum of 10 colonies counted in 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.

As this method has been validated for at least five food categories, this method is applicable for a broad range of foods. Since the method is not commonly used for samples in the primary production stage, this category was not included in the validation study. Therefore, no performance characteristics were obtained for this category. For detailed information on the validation see Clause 11 and Annex C.