The goal of this study was to examine the effects of operating parameters on ethanol concentration (ethanol) in apple wine production process. Examined parameters were temperature (T), pH and sulphurdioxide concentration (SO2). Experiments were planned and executed according to a full two-level factorial experimental design method. The studied levels were 18°C and 25°C for temperature, 3 and 4 for pH and 50 and 150 ppm for SO2. Ethanol concentration of apple wine for each set of experiments was determined by GC/MS. Experimental data were analyzed by using both graphical and quantitative Exploratory Data Analysis (EDA) Techniques. The main effect of each factor on sugar consumption rate (SCR) was also examined. The results show that the effect of examined operating parameters on ethanol was negative. High temperature level caused faster fermentation rate than the one caused by low temperature. Low level of pH and high level of SO2 inhibited the activities of both harmful microorganisms and wine yeast.

M. Deniz Bozoglu, Suna Ertunc, Bulent Akay, Nihal Bursali, Nilufer Vural, Hale Hapoglu and Yavuz Demirci