Optimization of Cactus Pear Fruit Fermentation Process for Wine Production

Cactus pear fruit (Opuntia ficus-indica) has a chemical composition that renders it an attractive substrate for wine fermentation. However, there have been serious post-harvest losses of cactus fruit due to its short shelf life. This study aims to investigate wine production from cactus pear fruit juice by optimizing fermentation temperature, pH, and inoculum concentration (Saccharomyces cerevisiae) to obtain optimum quality-indicative responses. Response surface methodology coupled with central composite rotatable design was adopted in the present study to achieve optimized fermentation process conditions. The fermentation process was carried out for 6 days with varied input variables, and all the models showed significant p-values for interaction of variance (<0.05). Cactus pear fruit wine with a total acidity of 12.39 ± 1.32 g/L equivalent to tartaric acid (TTAE), alcohol content of 9 ± 0.31%, v/v, total antioxidant concentration of 235.3 ± 9.15 mg/L AAE (Ascorbic acid equivalent), and sensory acceptance of 7.74 ± 0.34 was produced at an optimized temperature of 30 °C, pH of 3.9, and inoculum concentration of 16%. The developed models could predict the quality of wine developed from cactus pear fruit.