Physichochemical properties of kefir drink using modified porang flour (Amorphophallus oncophyllus) during storage period

Abstract

The purpose of this research was to compare physicochemical characteristics of goat milk kefir drink produced by using porang flour and modified porang flour throughout 21 days storage period. Goat milk kefir drink weretaken at 1, 7, 15 and 21 day of storage period, analysed for microstructure, particle size and ethanol content. Analyses of microstructure using confocal laser scaning microscopy (CLSM), particle size using particle size analyser,ethanol content usinggas chromatography (GC).There were significant differences considering the microstructure, particle size and ethanol content of goat milk kefir drink using modified porang flour during storage period.Lower ethanol content was observed in goat milk kefir drink with porang flour and modified porang flour as compared to control sample (no porang flour added) addition, lower ethanol in sample resulted from lower metabolism activity of microbial under lower water activity condition effect of glucomannan in porang flour. Goat milk kefir drink with modified porang flour addition produced lower particle diameter than control and porang flour treatment, it may due to the disruption of milk protein aggregate by modified porang flour. Confocal microscopy showed at modified porang flour treatment shows more homogenous protein milk aggregate.It can be concluded that modified porang flour produced lower ethanol content and particle diameter of goat milk kefir drink and more homogenous protein milk aggregate.