PENGARUH PENAMBAHAN PATI TAPIOKA TERHADAP PERTUMBUHAN Rhizopus sp. DALAM FERMENTASI KACANG MERAH (Phaseolus vulgaris L.) PADA PRODUK TEMPE

Tempeh is a fermented product generally made from soybeans, red beans (Phaseolus vulgaris L.) can also be used as an alternative ingredient. Mold growth in fermentation is influenced by the availability of nutrients, especially carbon sources. The addition of tapioca starch as an additional carbohydrate source is thought to support mold growth and affect the quality of tempeh. This study aimed to determine the effect of tapioca starch addition on the growth of Rhizopus sp. mycelium, the microscopic characteristics of the mold, and the organoleptic quality of red bean tempeh. This study used four treatments of tapioca starch addition, namely T0 (control, 0%), T1 (5%), T2 (10%), and T3 (15%). Mycelium growth was observed at 24 and 48 hours after incubation, microscopic characteristics were observed using a microscope, and organoleptic tests were carried out on color, aroma, texture, and taste of the tempeh. Mycelium growth data were analyzed using a one-way ANOVA test followed by a Duncan test. The results showed that the addition of tapioca starch significantly affected the mycelial growth of Rhizopus sp., with optimal growth in the T3 treatment (15%), especially after 48 hours after incubation. Microscopically, the mold growth showed typical Rhizopus sp. characteristics, including branched aseptate hyphae, erect sporangiophores, round to oval sporangia, and columella, with no morphological differences between treatments. The addition of tapioca starch also affected the organoleptic quality, with tempeh with added tapioca starch demonstrating better panelists acceptance than the control. Based on the results, the addition of tapioca starch increased mold growth and the quality of red bean tempeh without altering the microscopic characteristics of Rhizopus sp.

Keywords: Red bean tempeh, tapioca starch, Rhizopus sp. mycelial growth, organoleptic quality.