Formation of Frozen Blackcurrant Fruits Quality

Abstract

Aims: Fruits of a multivitamin culture of blackcurrant have a pronounced seasonality of consumption. The essence of the problem is in the scientific substantiation of the rational way of fruits freezing in order to preserve their quality.
 Place and Duration of Study: The research was conducted during four years in the conditions of the laboratory of the Department of Technology of Storage and Processing of Plant Products at Uman National University of Horticulture and the workshop for rapid freezing of Uman canning plant.
 Methodology: Prepared berries of the consumer degree of ripeness of Pilot Oleksandr Mamkin, Mynai Shmyriov, Novyna Prykarpattia, Biloruska solodka varieties in the string bags were frozen by slow (-20 to -22°С) and rapid (-30 to -32°С) methods, packed in paraffined boxes, polyethylene bags of 400–500 g by weight. Losses in fruit weight, content of ascorbic acid, dry soluble substances, sugars, acids, sugar-and-acid index were determined during and for 10 months of storage (-18°C).
 Results: True chemical composition of the fruits took into account losses of their weight. It radically changed the level of indicators. Weight losses of the fruits was lower by a third during fast freezing, however, the overall indicators did not differ significantly until the end of storage: 11.9–12.1% by slow method against 10.1–11.2% by rapid way. The highest losses in the fruits were during the first 3 months, during 4–5 months – their level was stabilized and somewhat increased to the end of storage. Advantages by fruits packing in polyethylene bags were as follows: losses were 6–7 times lower than by string bags and 4–5 times – in paraffined boxes. Advantages of rapid freezing were in 1.2–1.6 times lower losses of the components of chemical composition. Usually, the frozen fruits of Biloruska solodka variety were better than other varieties under favourable weather conditions, they were not inferior.