Brewer's yeast

Why this ingredient is used

Brewer's yeast (Saccharomyces cerevisiae) is a by-product of beer brewing that provides B-vitamins, chromium, selenium, and beta-glucan fibres. In pet food it serves three roles: nutritional supplement (natural B-vitamin complex), palatability booster (the umami flavour drives feeding), and sometimes flea deterrent (the B-vitamins create a skin sécrétion that some studies suggest repels fleas, though évidence is mixed). It is one of the cheapest functional additives and appears in both premium and budget formulas without controversy.