The aim of this master thesis was to test the effect of hot water dipping as a physical treatment to prolong storage life and maintain quality of cherries cv. Van. Cherries were dipped to water with temperature 45 °C, 52 °C and 60 °C for 5, 2 and 0,5 min respectively and stored for 14 days at +4 °C. The following physiochemical analyses were carried out: colour parameters L*, a*, b*, the contents of ascorbic acid, phenolic compounds, total phenols and flavonoids, antioxidant potential (AOP) and phenylalanin ammonia lyase (PAL) enzyme activity. Results showed that hot water dipping significantly effects the contents of the following phenolic compounds – cyanidin-3-glucoside (Cy3G), cyanidin-3-rutinoside (Cy3R), peonidin-3-rutinoside (P3R), neochlorogenic acid (NeochlAC), 3-p-coumaroylquinic acid (C3p), catechin, chlorogenic acid (ChlorAC), procyanidin B2 (PB2), epicatehin, quercetin-3-glucosyl-rutinoside (Q3GR), isochlorogenic acid (IsochAC) and quercetin-3-rutinoside (Q3R). The values of AOP, total phenols, flavonoids and anthocyanins were decreasing with increasing temperature of treatment – higher temperature means lower content of compounds. During storage, the contents of phenolic compounds were increasing. After storage, the individual phenolic compounds (except anthocyanins) were the highest in samples treated with water at 52 °C. There is positive correlation (r2=0,99) between enzyme activity PAL and content of anthocyanins – higher enzyme activity, higher content of anthocyanins. During storage, parameters L*, a*, b*, relative saturation and hue angle were decreasing. The smallest change of color was in samples treated with water at 52 °C. The most optimal temperature for treating cherries would be 52 °C for 2 minutes.
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