Changes in technological quality of frost damaged sugar beet during storage

Abstract

Both healthy and frost-damaged sugar beet were stored at different temperatures: 4, 12 and 20°C. Samples of sugar beet not damaged by frost were taken from storage after 20, 40, 48, 70 and 100 days, while samples of frost-damaged sugar beet were taken for further analysis after 8, 20, 28 and 36 days of storage. The content of dextran, mannitol and organic acids (lactic and acetic) were determined in the collected samples. The content of dextran was determined by ICUMSA Method GS8-19 (2007); the mannitol content by ICUMSA Method GS8-26 (2011); and the acids content by high performance anion exchange chromatography (HPACE) with a conductivity detector. The results show that in healthy sugar beet regardless of the storage temperature dextran was not found and the content of mannitol, lactic and acetic acid only slightly increased to an amount that would not harm processing of these beets. On the contrary, in frost-damaged sugar beet, which thawed during the initial stage of storage, the amount of undesirable compounds increased rapidly to an unacceptable level for processing depending on the storage temperature. Only storage at the low temperature of 4°C was able to postpone the formation of dextran in frost-damaged beets for about 10 days.