Objective : This study aimed to obtain a substrate that equally as good as sucrose but at a more economical price for fermentation Aspergillus tamarii of kojic acid production

Method : Media optimization is carried out using 3 different types of carbon sources such as sucrose, corn starch and cassava starch, also combining sucrose with corn starch and sucrose with cassava starch. Eight medium optimizations carried out on a small scale in shaker and optimization continued to a larger scale of fermentation with various variations of aeration and agitation in magnetic stirrer.

Result : Of the 8 medium optimizations carried out on a small scale, a medium with a mixture of  sucrose-corn starch (3: 2) substrate was obtained with the highest kojic acid value of 5.9716 g / L with a yield value of  0.1537 g/g. The optimal results of the kojic acid value on a larger scale obtained in the 500 mL medium using a magnetic stirrer bioreactor which was 1.4223 g/L of kojic acid

Conclusion : The best and effective medium obtained was sucrose - corn starch (3: 2) for fermentation of kojic acid production Larger scale of fermentation has not yet obtained satisfactory results because the result had not succeeded in exceeding the value of kojic acid on the small scale.