Microbiological criteria for food and drink

Phil Voysey, Food Microbiologist

Acceptable levels of microorganisms in foods and drinks and the methods used to determine them are important aspects of any product specification. A new Campden BRI member-funded research project will provide much-needed guidance and advice on what levels of microorganisms would be acceptable in different foodstuffs. Phil Voysey explains some of the issues involved with microbiological criteria.

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Phil Voysey

About Phil Voysey

Phil is a Section Manager in the Microbiology Department at Campden BRI and his Section’s duties include organising and running microbiology training courses and the Campden Microbiology Proficiency Scheme.

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Microbiological criteria are a way of separating good quality ingredients or final products or even factory environment from unacceptable ones. They consist of, not only of the level of microorganisms are present but methods are also important as is the number of samples taken.

There are different types of microbiological criteria, some are set in law which are obviously quite important, we call those microbiological standards, there are some that are agreements between buyers and sellers, we call those microbiological specifications and there are some that are self-imposed by companies and we call those microbiological guidelines.

Microbiological criteria are an important part of any product or raw ingredient specification and we get asked lots of questions each year on how levels of microorganisms are appropriate to those different ingredients. This project aims to bring together information that currently exists, from all sorts of publications, into one document so that a practitioner who's been asked to set a criterion for a situation or foodstuff has all the information to hand that they can make most use of. We're planning to look at as many foodstuffs as we can, as many as there is information for. We're not planning to develop criteria for new foodstuffs but we'll be covering ingredients as well as finished products - things like water and also the manufacturing environment as well. We have a consultative group which we've set up to help us guide the project and there'll be three meetings of that group over the year of the project. We've already had one meeting, we've got at the meetings planned for June and October of this year so there's plenty of opportunity for anyone to have an input if this is an area of interest to them.

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