INFLUENCE OF CHITOSAN ON THE QUALITY OF RASPBERRIES DURING REFRIGERATED STORAGE

Abstract

Raspberries is a perishable berry with a high capacity for mechanical and microbiological damage, therefore, after harvesting, it is necessary to use appropriate technologies to preserve its quality and extend the shelf life. The aim of the research is influence of different concentrations of chitosan solutions on the quality and shelf life of raspberry berries under cooling conditions. Physico-chemical and organoleptic methods of research and methodological principles of collection, accumulation, systematization, analysis, generalization, and synthesis of information were used in the research. Raspberry berries were collected in the consumer stage of ripeness in perforated plastic containers with a capacity of 500 g. Processing of berries was carried out by spraying 0.5 %; 1.0 % and 2.0 % chitosan solution followed by removal of residual moisture. Storage was carried out for twelve days in a refrigerating chamber at a temperature of 2º C and a relative humidity of 95 %. The research was carried out by determining changes in the mass fraction of ascorbic acid, sugars during storage, as well as taste, aroma, color, consistency and appearance at the end of storage. It was established that the treated berries had 1.5–3.9 times less loss of ascorbic acid than in the control sample. A similar situation was observed with the mass fraction of sugars, the content of which prevailed by 0.9–2.5 % in processed raspberry samples. According to organoleptic indicators, samples with a solution concentration of 1.0 % and 2.0 % were recognized as the best. Raspberries not treated with chitosan quickly lost their marketable appearance, taste and aroma. It was found that pre-treatment of berries with chitosan solutions is a promising way to slow down undesirable metabolic processes during storage, which are carried out after harvesting, which practically makes it possible to extend the consumer properties of the product.