Characteristics of Tempeh Prepared from Several Varieties of Indonesian Soybeans: Correlations between Soybean Size and Tempeh Quality Properties

Abstract

Abstract Tempeh is a fermented soybean-based food that has long been an important protein source in Indonesia. In this study, tempeh was made from several varieties of soybeans to evaluate the differences in the characteristics of the tempeh produced. The soybean varieties used consisted of Anjasmoro, Grobogan, Dena, Dega and Biosoy, as well as imported soybeans. Characterization was carried out on both the soybeans and tempeh, including proximate composition, fatty acids, amino acids and textural properties. Pierce correlations were evaluated between seed sizes and quality parameters of soybean seed and tempeh. Dega and Biosoy had seed size closed to those of imported soybeans, which were favored by tempe producers. Different varieties of soybeans produced different characteristics of tempeh. Local soybean had superior quality of proximate composition, both in seed and tempeh. Sizes of soybean seeds had strong correlations with their dimension (length, height, thickness) (0.61, 0.59 and 0.58, respectively), but had weak correlations with proximate compositions, both for the soybean seed and their tempeh produced. Negative strong correlations were found in size of soybean seed and tempeh texture, showing a stronger and more compact texture of tempeh made from smaller seeds of soybean (-0.73). This study showed that soybean size had low correlations with the superior proximate characteristics of local soybean, providing useful information in expanding the choice of local soybean varieties as raw material for tempeh.