Microbiological and Sensory Properties of Tempeh as Influenced by Type of Legumes and Storage Temperature

Abstract

Bambara groundnut and lima bean are lesser-known legumes with high protein content. These legumes were incorporated into tempeh; a soybean-based snack to advance their uses as food. This research studied effects of the legumes on microbiological, physicochemical and sensory properties of tempeh during storage at ambient and refrigeration temperatures. The results showed that the total viable count of bacteria and fungi count of tempeh mash ranged between 6.173 - 7.903 logcfu/g and 6.602-6.799 log cfu/g respectively. The microbial load of the refrigerated fried tempeh snacks was lower than samples at room temperature. Blends of the three legumes (4.079 – 7.297 logcfu/g) had the highest total viable count while lima bean tempeh (3.903-5.602 logcfu/g) had the lowest. Bacillus cereus, Staphylococcus epidermidis, Bacillus coagulan, Bacillus subtilis, Bacillus alvei, Bacillus Licheniformis, Micrococcus cryophilus, Propionibacterium species, Rhizopus oryzae, Rhizopus stolonifer and Geotricum sp were isolated from tempeh snacks during storage. The results of the sensory assessment showed that lima bean tempeh snack was the most preferred. This research therefore suggests the use of lima bean and blends of lima bean, Bambara groundnut and soybean in production of tempeh to advance the use of these underutilized legumes and increase food security.

Keywords

• tempeh
• lima beans
• bambara groundnut
• rhizopus oryzae
• lima bean