Affiliation:
1. Ethiopian Institutes of Agricultural Research, Debrezeit Agricultural Research Center, Debrezeit, Ethiopia
Abstract
Winemaking is one of the most ancient technologies and is now one of the most commercially prosperous biotechnological processes. Fruits are one of the most important foods of mankind. They are important for the maintenance of health and improving the quality of our diet. Fruit juices are fermented to produce wine, an alcoholic beverage containing 8 to 11 percent alcohol and 2 to 3 percent sugar with energy values ranging between 70 and 90 kcal per 100ml. Due to the release of amino acids and other nutrients from yeast during fermentation, fruit wines are nutritive and tastier. For this reason, the conversion of fruits to value-added products like wine is very essential. This work aimed to produce and optimize mixed fruit (Banana and Watermelon) wine using saccharomyces cerevisiae. The proximate composition of banana with74 ± 00 of moisture content, 0.33 ± 00 of ash content, 0.23 ± 0.01 crude fat content, 1.65 ± 0.05 crude fiber content, 1.2 ± 0.1 protein content and 22.59% carbohydrate content and 91.5±1.5 moisture content, 0.49 ± 0.017ash content, 0.25 ± 0.01crude fat content, 0.6 ± 0.05 crude fiber content, 0.46 ± 0.02 crude protein content and 6.75% of carbohydrate content watermelon fruit were used for wine production. Primary and secondary fermentation of the fruits lasted for 9 and 21 days respectively, pH, titrable acidity, specific gravity and, total soluble solids (brix) were determined before and after fermentation using standard procedures. The specific gravity of the wine was observed to reduce drastically as the fermentation progressed. The pH of the fruit must decrease from 3 to 2.89 and 4 to 3.2 in different percentage of mixture and titrable acidity also increased 0.67- 0.92 in 75B:25Wm, 0.64 -0.9 in 50B:50Wm, and 0.63-0.89 in 25B:75Wm after fermentation. The highest percentages of alcohol content (9.5) was observed in 75B to 25Wm mixed fruit wine in pH 4 and inoculum size 5, and sensory evaluation revealed that the attributes of the wine were acceptable to the majority of the respondents. This study showed that acceptable wine can be produced from mixed fruits banana and watermelon using yeasts Saccharomyces cerevisiae.