Production of semi-dry wine using cape gooseberry under very high gravity conditions with preserved antioxidant properties.

In this study, we have reported production of a semi-dry fruit wine using Cape Gooseberry for the first time using very high gravity conditions at laboratory scale. Employing industrial strain Saccharomyces cerevisiae, the batch fermentation was carried out at room temperature in 1-l flasks in triplicates. The moisture content of fruit was calculated to be 80% after 24 days. The °Bx of raw fruit juice was found to be 4.9 and was raised to 25°Bx on addition of sucrose, the yeast assimilable nitrogen content of cape goose berry juice was calculated to be 280 mg N/L. Average fermentation time calculated based on cessation of bubbling and attainment of final °Bx of 3.8 ± 0.3 was found to be 21 days. The initial pH of raw juice was observed to be 4.51 ± 0.04 before fermentation, while post fermentation it was calculated to be 3.63 ± 0.03. The ethanol estimated using HPLC, GC-FID and refractometric analysis showed concentration of 13.29 ± 0.26, 13.15 ± 0.03 and 13.63 ± 0.374% respectively. The antioxidant activity of raw juice vs processed cape gooseberry wine was calculated to be 65.06% and 39.64% respectively, while it was estimated to be 53.86% in one-year-old preserved cape gooseberry wine sample. The titratable acidity and volatile acidity of wine was determined to be 6 g/l and 0.15 g/l respectively and was found to be well within the desired range. Our results provide a clear demonstration of feasibility of very high gravity fermentation for producing semi-dry Cape Gooseberry wine with moderate antioxidant preservation.