Technology refinement for wine production from under exploited fruits

Abstract

The present study entitled “Technology refinement for wine production from under exploited fruits” was conducted at Department of Post Harvest Technology, Kerala Agricultural University, College of Agriculture, Vellayani during the year 2019-2021 with the objective for technology refinement for wine production from under exploited fruits based on quality parameters and storage stability. Fruit wines were prepared from three under exploited fruits viz., jamun, papaya and rose apple independently by varying the process parameters viz., fruit: water ratio, fruit: sugar ratio, nitrogen source and clarification methods. Fruit: water ratio was tried at 1:1, 1:2 and 1.0.07; fruit: sugar ratio at 1:1, 24° brix and at 20% sugar, with or without nitrogen source and subjected to clarification by pectinase enzyme and by settling, thus forming 36 different wines under each fruit and were analysed for physical, chemical, nutritional and sensory quality parameters. The study was conducted as four continuous steps viz., fruit wine preparation, quality analysis, selection of superior wines and evaluation of storage stability. Jamun wines were attractive dark purple, had good flavour with 71.8 to 95.4 per cent yield. Papaya wines were light yellowish, papaya flavoured and had 42.2 to 90.7 per cent yield. Rose apple wines were creamy white with 82.24 to 93.33 per cent yield. Three wines with high yield, antioxidant activity and total sensory score with low alcohol content (<7%) were selected from each fruit. Jamun wine prepared using 1:1 fruit: water ratio, 1:1 fruit: sugar ratio, without nitrogen source and clarified by pectinase had 3.52% alcohol, 93.03% antioxidant activity and 253.29 mgg-1 polyphenol content with the highest total sensory score (18.5). When nitrogen source was added, the wine had highest (95.4%) yield, 3.52% alcohol content and high antioxidant activity (92.5%). The highest antioxidant activity (95.64%) was obtained for the wine produced using 1:2 fruit: water ratio, 1:1 fruit: sugar ratio, with nitrogen source and clarified by pectinase. This wine had 92.8% yield, 5.85% alcohol content and 125.92mgg-1 polyphenol content. Papaya wine produced with 1:1 fruit: water ratio, 1:1 fruit: sugar ratio, with nitrogen source and clarified by settling had 87% yield, 4.39% alcohol, 50.19mgg-1 polyphenol and 86.93% antioxidant activity. Addition of nitrogen source and clarification by pectinase had resulted in wine with highest total mean sensory score (17), 3.52% alcohol, 83.65mgg-1 polyphenol and 86.54% antioxidant activity. Wine prepared with 1:2 fruit: water ratio, 1:1 fruit: sugar, with nitrogen source and clarified by pectinase had high yield (90.7%), 5.13% alcohol, 56.55mgg-1 polyphenol and 82.95% antioxidant activity. 186 Rose apple wine prepared with 1:1 fruit: water ratio, 1:1 fruit: sugar, without nitrogen source and clarified by settling had 92.33% yield, 3.52% alcohol, 112.34mgg-1 polyphenol and 75.12% antioxidant activity with highest total mean sensory score (16). Preparation of wine with 1:1 fruit: water ratio, 1:1 fruit: sugar, with nitrogen source and clarified by pectinase had resulted in wine with 91.33% yield, 3.52% alcohol, 151.65mgg-1 polyphenol and 80.13% antioxidant activity. The wine produced using 1:2 fruit: water ratio, 1:1 fruit; sugar ratio, without nitrogen source and clarified by settling had 93.33% yield, 4.39% alcohol, 108.66mgg-1 polyphenol, high antioxidant activity (83.33%) and highest total sensory score (16). When the superior wines selected from each fruit were stored in amber coloured glass bottles and analysed for storage stability, it was seen that the polyphenol content decreased during storage. All the wines were microbiologically safe till the end of two moth storage. In general, utilization of pectinase for clarification, addition of nitrogen source and clarification by pectinase or by doubling the water content in addition to nitrogen source and use of pectinase can improve yield, antioxidant property and sensory score of jamun wine. Addition of nitrogen source, use of pectinase and nitrogen source or doubling the water content with nitrogen source and use of pectinase can improve yield and sensory score of papaya wine. But alcohol content and antioxidant activity were significantly reduced by doubling water in addition to use of nitrogen source and pectinase. By doubling the water content or usage of a nitrogen source and pectinase enzyme, no significant improvement could be made in yield or alcohol content of rose apple wine; instead the antioxidant activity could be significantly improved. The study clearly points out the relevance of selecting process parameters based on the quality of raw material used for wine making.