QUALITY DEVELOPMENT OF UNFORTIFIED WINE MATERIALS FROM PEARS, CHERRIES, BLACK CURRANTS AND GOOSEBERRIES USING CRAFT TECHNOLOGIES

Abstract

Fruit and berry raw materials for the production of unfortified wine materials in 2021 and 2023 were studied: Konferentsiia variety pears, Zustrich variety cherries, Amethyst variety black currants, Krasen variety gooseberries, grown in the conditions of the Central Forest Steppe of Ukraine. Depending on the type and variety, the fruits differed significantly in the content of sugars and titrated acids. Natural pear juices had a high sugar content of 142–150 g/dm3 at a low titrated acid content, only 2.2– 2.7 g/dm3. In natural charry juices, the mass concentration of titrated acids was 9.8-10.2 g/dm3, black currant – 24–28 g/dm3, gooseberry – 16–18 g/dm3. To normalize juices according to the mass concentration of titrated acids, natural pear juices were concentrated, cherry juices were suitable for the wort making. The calculated sugar amount and 10% of the fruit were added to the juices after stone removing, the wort was pasteurized and cooled. Natural blackcurrant and gooseberry juices required a decrease of the titrated acid mass concentration in the wort before fermentation to a level no higher than 9.5 g/ dm3. The required amount of drinking water and sugar was calculated for the determined yield of fruit juice. The water was brought to a boil, sugar and fruit were added, the wort was pasteurized: the temperature was brought to 85˚C, kept for 3 minutes, and cooled. The wort was fermented with fruit using regenerated yeast of the ES-1118 race in the amount of 2.5 g/dal at a room temperature of 18-24˚С. The mass sugar concentration in the wort before fermentation was as follows: pears and gooseberries – 255 g/dm3, cherries – 280 g/dm3, blackcurrants – 249 g/dm3. The volume fraction of ethyl alcohol in pear wine was 14.6–14.8%, cherry wine – 16.0–16.5, black currant wine – 14.4–14.5, gooseberry wine – 14.3–14.9%; mass concentration of residual sugars was 3–12 g/dm3; titrated acids in pear wines – 4.5–5.6, in the rest – 7.2–8.7; volatile acids – not higher than 0.9; the residual extract was high – 26.6–50.8 g/dm3. According to physical and chemical indicators, pear wine materials can be used for making unfortified blended wines, the rest – for varietal and blended wines. Phenolic substances and ascorbic acid were remained in unfortified wine materials. In natural pear juices, the mass concentration of phenolic substances was 420–650 mg/dm3 and of ascorbic acid – 102–130 mg/dm3, preservation in wines in relation to the content in natural juices – 109 and 103%, respectively; in natural cherry juices the mass concentration of phenolic substances was 2400–2950 mg/dm3 and of ascorbic acid – 300–345 mg/dm3, preservation in wine materials was 80 and 70%, respectively; in natural blackcurrant juices, the mass concentration of phenolic substances was 7,800–9,050 mg/dm3 and of ascorbic acid – 1,400–1,500 mg/dm3, preservation in wine materials – 26 and 22%, respectively; in natural gooseberry juices, the mass concentration of phenolic substances was 2850–3900 mg/dm3 and of ascorbic acid – 520–680 mg/dm3, preservation in wine materials – 34 and 36%, respectively. It has been confirmed that with a higher content of biologically active substances in raw materials, their losses during processing are greater, but the content in wine materials is higher.