Optimization of enzymatic clarification of sapodilla juice: a statistical perspective.

Response surface methodology (RSM) was employed to establish optimum conditions for enzymatic clarification of sapodilla juice. Polygalacturonase obtained from Streptomyces lydicus had been purified to homogeneity and was used for the treatment. The independent variables were temperature (30-45 degrees C), enzyme concentration (0.5-1.5 U), and treatment time (30-90 min), whose effects on viscosity and clarity of the juice were evaluated using a Box-Behnken design. Significant regression models describing the changes of viscosity and clarity with respect to the independent variables were obtained, with the coefficient of determination, R (2) , greater than 0.8. Based on response surfaces and contour plots, the optimum conditions for clarifying sapodilla juice were enzyme concentration 1.15 U, incubation temperature 34 degrees C, and incubation time 70 min.