The Effect of Sucrose and Yeast Extract on Total Phenolic, Flavonoid, and Anthocyanin of Lactic-Acid-Fermented Mangosteen Fruit Peel ( Garcinia mangostana L.)

This study aimed to determine the most suitable concentration of sucrose and yeast extract (SYE) and its impact on the levels of total phenol, flavonoid, and anthocyanin (TPFA) for lactic acid fermentation in mangosteen fruit peel. In this study, the primary components were mangosteen fruit peel, SYE, and lactic acid bacteria starter. The experimental design was conducted using the Factorial Design method. The colorimetric method was used to determine the total phenol (Folin-Ciocalteu reagent) and total flavonoid (AlCl reagent). In addition, the differential pH method was used to determine the total anthocyanins using KCl and the CH COONa reagent. The addition of SYE during the fermentation of mangosteen fruit peel significantly increased the concentrations of TPFA compared with the control ( value of 0.0001). The high sucrose concentration and low yeast extract produced the highest TPFA levels in mangosteen rind fermentation. The use of SYE affects the levels of TPFA in lactic acid-fermented mangosteen fruit peel, with the most suitable concentrations obtained using sucrose (45 g/L) and yeast extract (2.5 g/L).