Patterns and Formation of Fatty Acids at Tempe Fermentation by Several Strains of Rhizopus Sp.

Abstract Several fungi and bacteria have been isolated and determined from Indonesian tempe and soaking water. It could be shown that strains of Rhizopus sp. metabolize the soybean lipids and change the fatty acid composition only little. In principle the fatty acid composition of tempe represents a composition close to that of soybeans with an increased content of oleic acid. During a fermentation the degree of unsaturation decreased due to decreasing linoleic acid and alpha‐linolenic acid and increasing oleic acid. The intracellular fatty acid composition of the fungi differed widely in dependence on the culture conditions used. If the fungi were forced to produce their lipids de nove, an inversion of linolenic acid position isomers appeared, gamma‐linolenic acid reached values up to 21%. In comparison with mycelium grown on soybeans there was a loss of linoleic acid for the benefit of all the other fatty acids, especially oleic acid. A significant loss of total lipids during a fermentation could not be found.