NITA CITRASARI, IRMA ARDIANA PUSPITA AND AGUS SUPRIYANTO
Abstract
This study was aimed to determine the effect of the variations of extract concentration, the variation of the length of fermentation time, and the combination of both on ethanol produced. Ethanol fermentation used Pasar Induk Osowilangun Surabaya (PIOS) fruit wasteââ¬â¢s substrates that was extracted then added with 10% Saccharomyces cerevisiae. This study used 4x4 factorial design, 2 factors, and 3 replications. The first factor was the concentration of fruit wasteââ¬â¢s extracts (25, 50, 75 and 100%). Second factor was the length of fermentation time (3rd, 6th, 9th, and 12th days). Reducing sugar measurement used Luff Method and ethanol amount measurement used Pycnometri Method. Etanol amount was subjected to variance analysis with Two Ways Anova test (á 5%), continued with Duncan test. The treatment of fruit wasteââ¬â¢s extract concentration effected ethanolââ¬â¢s amount, the maximum concentration in 100 % fruit wasteââ¬â¢s extract (6.9%). The treatment of fermentation time effected ethanolââ¬â¢s amount, the optimum of fermentation time on the 9th days (5.15%). The combination treatment between the variations of fruit wasteââ¬â¢s extract concentration and fermentation time effected ethanolââ¬â¢s amount, the maximum 100% fruit wasteââ¬â¢s extract within the optimum 9th days fermentation (8.12%).