Yahav, S., Department of Food Quality and Safety, Institute for Postharvest Technology and Food Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel, The Robert H. Smith Faculty of Agriculture, Food and Environment, Institute of Biochemistry, Food Science and Nutrition, The Hebrew University of Jerusalem, Rehovot, Israel; Berkovich, Z., The Robert H. Smith Faculty of Agriculture, Food and Environment, Institute of Biochemistry, Food Science and Nutrition, The Hebrew University of Jerusalem, Rehovot, Israel; Ostrov, I., Department of Food Quality and Safety, Institute for Postharvest Technology and Food Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel, Biofilm Research Laboratory, Hebrew University-Hadassah, Jerusalem, Israel; Reifen, R., The Robert H. Smith Faculty of Agriculture, Food and Environment, Institute of Biochemistry, Food Science and Nutrition, The Hebrew University of Jerusalem, Rehovot, Israel; Shemesh, M., Department of Food Quality and Safety, Institute for Postharvest Technology and Food Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel

Probiotics, live microbial supplements, are often incorporated into foods and beverages to provide putative health benefits. To ensure their beneficial effects, these organisms must survive processing and storage of food, its passage through the upper gastrointestinal tract (GIT), and subsequent chemical ingestion processes until they reach their target organ. However, there is considerable loss of viability of probiotic bacteria in the acidic conditions of the stomach and the high bile concentration in the small intestine. Bacillus subtilis, a spore-forming non-pathogenic bacterium, recently has gained interest in its probiotic properties; it can effectively maintain a favorable balance of microflora in the GIT. In addition, B. subtilis produces an extracellular matrix that protects it from stressful environments. We suggested that the extracellular matrix produced by B. subtilis could protect other probiotic bacteria and therefore potentially could be used as a vehicle for delivering viable probiotic cells to humans. Therefore, we developed a novel cultivation system that enables co-culturing of B. subtilis along with probiotic lactic acid bacteria (LAB) by increasing production of the extracellular matrix by B. subtilis cells. Moreover, we showed that B. subtilis improved survivability of LAB during food preparation, storage and ingestion. Therefore, we believe that the results of our study will provide a novel technique of using a natural system for preservation and delivery of probiotics to humans. © 2018 Informa UK Limited, trading as Taylor & Francis Group