The role of lactic acid bacteria on safety and quality of fermented foods

Abstract

Indonesia, one of the Asian countries, has many kinds of fermented food which coverage area are from Sumatera to Papua. Fermented food product is processed food through fermentation process, where certain microorganisms play an important role during the process. Growth of undesirable wild microorganisms may cause fermentation failure and results in undesirable products. Many researches have been done to explore fermented foods from several areas such as dadih and tempoyak (Sumatera); ikan peda, petis, oncom, tape, tempe and kecap (Jawa); brem, urutan, bebontot, brengkes (Bali); sour horse milk (NTB); sei (NTT); and bekasang (Sulawesi). From these products, the usage of many kinds of microorganisms are also explored. Most of them are of a group known as lactic acid bacteria (LAB), which has been used as starter culture, as well as probiotic. By using LAB as starter culture, some benefit such as acceleration in the process and ensure quality and safety of the products, were shown. During fermentation, LAB produce lactic acid and other metabolites that respectively lower the pH and limit the growth of pathogenic microorganisms. The bacteria also release hydrolytic enzymes (lipases and proteases), which are able to break down macromolecules, such as lipids and proteins, resulting in the production of precursors for specific aroma. The discussion in this paper is focused on the role of LAB on safety and quality of fermented food, especially urutan (Balinese fermented or dried sausage) and sour horse milk.