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Fermentation by using Saccharomyces cerevisiae is a potential method to produce the Virgin Coconut Oil (VCO). A parametric study using Box-behnken design was used to evaluate interaction effect of stirring speed, inoculum concentration and fermentation time on the percentage of oil recovery. The results indicated that fermentation time is most significantly affecting the rate of oil recovery. The surface and contour plots show that the oil recovery is gained up to 88.607% for stirring speed of 175-250 rpm, inoculum concentration of 0.2-0.3% (w/v), and fermentation time of 16-24 hours. GC analysis results indicate that the high lauric acid content of 53.0249%, is obtained when stirring speed of 200 rpm, inoculum concentration of 0.3% (w/v) and fermentation time of 24 hours. A parametric study has been successfully implemented in the production of VCO using fermentation method with the coefficient of determination (R 2 ) of 97.57%.

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Virgin coconut oil (VCO) is coconut oil that processed without heating. This study about fermentation of VCO using Saccharomyces cerevisiae. The purposes of this research is to find the best condition like stirring times, stirring speeds,  fermentation times and concentration of inoculum in the process of making VCO. The variation of stirring speeds are 25 rpm, 50 rpm, 75 rpm, 100 rpm and 125 rpm. Stirring time used was 15 minutes, 30 minutes, 45 minutes, 60 minutes and 75 minutes. The variation of fermentation times are 6 hours, 12 hours, 18 hours, 24 hours, and 30 hours and variation concentration of inoculum are 5%, 10%, 15%, 20% and 25%. For stirring effects, the highest yield was obtained 24,5% with stirring speed is 50 rpm and stirring time is 30 minutes and the lowest yield was obtained 8,5% with stirring speed is100 rpm and stirring time 75 minutes. For fermentation times and concentration inoculum effets, the highest yield was obtained from this research is 28,25% with addition inoculum is 10% and fermentation times is 24 hours. And the lowest yield is 15% with addition inoculum is 20% and fermentation times is 12 hours. The results of this research for stirring effects showed decreases yield of VCO and for the fermentation time showed increases yield of VCO and concentration inoculum showed no effect for  yield of VCO.

Response Surface Methodology (RSM) is successfully used to obtain the optimum conversion of oleic acid on the synthesis of fatty amide surfactants from oleic acid and diethanolamine by immobilized lipase. The central composite design is adopted to determine the optimum level of three study variables, i.e. enzyme amount, substrate molar ratio, and temperature. The model resulted in this study is suitable to represent the interaction among three variables and also their interaction to the conversion of oleic acid. The influence of substrate molar ratio is more significant among others. The prediction of the statistical model shows that the maximum conversion of oleic acid would be 78.01% at the optimal condition of 5-9% (wt/wt OA) enzyme amount, 1/1 to 3/1 molar ratio of diethanolamine to oleic acid and 60-65 o C temperature. The coefficient of determination (R 2 = 0.9897) shows a high correlation between predicted and experimental values.

The present study deals with the oxidative cleavage of oleic acid (OA) using hydrogen peroxide and tungstic acid as a catalyst to produce azelaic acid. A two-step method has been expanded for the optimization of a new route of azelaic acid synthesis with the addition of sodium hypochlorite as the co-oxidation. The Central Composite Design (CCD) and Response Surface Methodology (RSM) were performed to optimize the production of azelaic acid. The interaction effect among catalyst concentration, substrate molar ratio and temperature were done for optimization the conversion of oleic acid. Maximum oleic acid conversion of 99.11% was reached at substrate molar ratio of 4/1 (H 2 O 2 /OA), a catalyst concentration of 1.5% (w/wOA) and temperature of 70 o C. The GC analysis shows that the yield of azelaic acid is 44.54% and pelargonic acid is 34.12%. These results indicate that the proposed process show a good strategy for the synthesis of azelaic acid from oxidative cleavage of oleic acid.