Functionality of thermophilic bacteria as probiotics

Abstract Currently, most of the consumed foods are highly processed, some of them are submitted to a heat process to get sterilized, to be cooked, to change its consistency, etc. A large number of food producers want to inoculate probiotics to their products to make them functional foods, with the risk of losing those microorganisms during the heating step, taking out the functionality they may have. Therefore it is necessary to search for thermoresistant probiotics that can be inoculated to different types of putative functional foods. An excellent example of these microorganisms is the lactic acid bacteria (LAB). These microorganisms produce organic acids during their metabolism. In addition, these microorganisms have the capacity to inhibit the growth and proliferation of pathogenic bacteria in foods. LAB also develops an environment with reduced pH, which prevents pathogenic bacteria survival, plus adding enjoyable flavors to some foods (like yogurt and cheese). But, some thermal treatments can change, inactivate, or even kill these LAB by damaging its structure and, consequently, its functionality. This review pretends to recollect and discuss the updated information on different thermoresistant probiotic bacteria already characterized, which could be inoculated to different foods to make them functional. Thus they can pass through a thermal treatment without losing their properties.