Effect of a partial drying pretreatment on the respiration activity of fresh-cut apple.
Senesi E.
5th International Postharvest Symposium . Volume of Abstract . Verona, Italy 6-11 June 2004. page 25
2004
บทคัดย่อ
Fresh-cut apple segments (cv Golden Delicious) were dried up to a water loss of 10%, 20%, 30%, 40% and 50% in an air dryer set at a constant temperature of 50 °C.Partially dried apple segments were checked for the respiration (rate of O2 consumption and CO2 production in a sealed container until 24 hours), ethylene production (amount of ethylene produced in one hour in a sealed container until 24 hours), water activity (aw), total soluble solids, titratable acidity and pH.
The results showed some changes of the chemical indexes (aw, total soluble solids, acidity and pH) which were related to the level of the partial drying.The fresh-cut apple segments maintained the respiration even at 50% weight loss.After 24 hours, the oxygen percentage decreased to 19.55, 19.60, 18.65, 19.39, 19.20, 19.96% and carbon dioxide increased to 1.50%, 1.40%, 2.40%, 2.05%, 1.5% and 0.85% in, respectively, untreated samples, 10%, 20%, 30%, 40% and 50% weight loss.Ethylene production showed a trend to increase in all the samples but the amount varied noticeably.Untreated samples showed a peak after 7 hours.The 50% dehydrated samples showed the minimum amount of ethylene production (22 ppm kg-1 h-1) while the highest amount was showed by the 30%, 20% and 10% dehydrated apple segments (respectively 109.5, 90.3 and 78.9 ppm kg-1 h-1 after 24 hours).
The experiments demonstrated that the respiration is not completely inactivated by partial drying even at 50% water reduction and that the drying parameters can have some influence on the respiration rate.