Abstract
The commercial production of xanthan gum is highly dependent on the type of carbon source used. Commonly, glucose is used as the carbon source for xanthan production due to its high yield of xanthan but the cost of the glucose can also be significant. Alternative should be considered for the large production scale of xanthan gum in industries to reduce the production costs. Therefore, this study evaluates the use of tapioca starch as the carbon source in fermentation due to its low cost and readily available source in Malaysia. There were two types of tapioca starch used in the fermentation: pure and hydrolyzed tapioca starch. The fermentation conditions were optimized such as period of fermentation, age of inoculum, pH, percentage of inoculum, temperature, and concentration of carbon source. It was found that the optimal period of fermentation was 96 hours, optimal age of inoculum was 48 hours, optimal pH was 7.0, optimal percentage of inoculum was 10%, optimal temperature was between 28°C and 30°C, and optimal concentration of carbon source was between 30g/l and 40g/l for fermentation medium, which using tapioca starch as carbon source and between 50g/l and 70g/l for fermentation medium, which using hydrolyzed tapioca starch as carbon source. The maximum xanthan yield was 22.36 g/l using hydrolyzed tapioca starch as carbon source. Thus, hydrolyzed tapioca starch could be recommended as a carbon source in fermentation of xanthan gum.
