Change of quality characteristics of onion during merchandising in retail trade

When selling fruits and vegetables in retail stores, the question arises of the preservation of their consumer properties. Therefore, the task was set to follow the changes in the quality of onions in a trading hall for seven days, which corresponds to the time of sale of the goods. Onions, unlike other vegetables, less interact with the air. Therefore, the loss of moisture and organic substances is insignificant. The paper presents data on the change in the qualitative characteristics of onions in the conditions of a trading hall and refrigerated storages for 7 days. Obtaining and processing of experimental data on the changes in sugar onion, ascorbic acid and moisture content was carried out in the laboratories of commodity science and food products expertise of the Department of Trade and Goods Science of the St. Petersburg State University of Economics. The partial increase in acidity during prolonged storage could be a consequence of the breakdown of sugars during fermentation. As a result of the conducted researches it is established that the biochemical processes taking place in onions practically do not depend on the temperature decrease in the room. It is recommended to pre-dry the onions for better preservation. It is necessary to carry out quality control of the product by organoleptic and physicochemical parameters during refrigerated storage and storage in the trading floor. It is established that the content of vitamin C does not decrease in the process of realization of onion if the humidity of air does not exceed 65%. The experiments showed that the loss of sugars during storage does not occur. Essential loss of moisture, and consequently, a decrease in the mass of the product, was not observed.