Public health issues arising from microbiological and labelling quality of foods and supplements containing probiotic microorganisms.

Abstract

To assess the accuracy and helpfulness of labelling on products containing probiotic bacteria. 52 such products - 44 from the UK (21 supplements, 15 fermented functional foods, eight 'health-care' products) and eight from continental Europe - have been tested for microbiological content, and results compared to the information available on their labels. Products were stored in the dark at 4 degrees C and analysed before their expiry or sell-by date. Careful note was taken of wording on labels, package inserts, packaging, promotional literature and catalogue descriptions, as applicable. Products were cultured on appropriate bacteriological media, and organisms grown were counted and identified. Bioyoghurts gave no indication of numbers, and only five accurately described their bacterial content; results of culture were usually satisfactory. 'Healthcare' products (mostly intended for the bowel) usually indicated the presence of bacteria, but the numerical content was hard to ascertain, and cultural results fell short of label claims. Supplements were sometimes incorrectly labelled in bacteriological terms, and often contained markedly reduced numbers and/or had extraneous strains and/or strains specified on the label were missing. Products from continental Europe (that were sold for specific medical indications) seemed of a higher microbiological standard. The potential pathogen Enterococcus faecium was found in nine products. The most successful of the new functional foods in Britain now contain probiotics, and probiotic preparations are prominent among the expanding range of nutritional supplements presently available to consumers. Our findings have public health implications, and suggest that improvements are needed in labelling and quality assurance procedures for products containing probiotic organisms. The presence of the potential pathogen Enterococcus faecium (intentionally or as a contaminant) in some products calls for a review of the value of this species as a probiotic.