Probiotics are dietary supplements containing potentially beneficial bacteria or yeasts. According to the currently adopted definition by FAO/WHO, probiotics are: ‘Live microorganisms which when administered in adequate amounts confer a health benefit on the host’. Lactic acid bacteria (LAB) are the most common type of microbes used. LAB have been used in the food industry for many years, because they are able to convert sugars (including lactose) and other carbohydrates into lactic acid. This not only provides the characteristic sour taste of fermented dairy foods such as yogurt, but acts as a preservative, by lowering the pH and creating fewer opportunities for spoilage organisms to grow. Strains of the genera Lactobacillus and Bifidobacterium, are the most widely used probiotic bacteria.
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Pro·bi·ot·ic n. A dietary supplement containing live bacteria or yeast that supplements normal gastrointestinal flora, given especially after [more]Probiotic - Community and Resources