Properties of Goat Milk Kefir Supplemented with Glucomannan from Porang (Amorphophallus oncophyllus) Tuber

Abstract

Properties of kefir depends on the kinds of milk as raw material, grain sources and other components which to be added within the fermentation process. Glucomannan is known as stabilizer and thickener that to be added in food processing.  The objectives of this study were to evaluated the effect of glucomannan supplementation in fermentation process on microbiological, chemical and physical characteristics of goat milk kefir.  Goat milk kefir were prepared by goat milk; goat milk+whey protein concentrate (WPC); goat milk+ glucomannan; and goat milk+WPC+glucomannan.   The results showed that there were no effect of WPC, glucomannan or combination of WPC and glucomannan supplementation on kefir characteristics including the total lactic acid bacteria, yeast and total count, moisture and alcohol contents, acidity, pH and viscosity. The viscosity of kefir supplemented with combination of WPC and glucomannan tend to have a lower viscosity compared to kefir supplemented with WPC or glucomannan individually, although it was not significantly different. In conclusion, supplementation of WPC and glucomannan from porang tuber in fermentation process had no adverse effect on microbiological, chemical and physical characteristics of goat milk kefir.