Fruit quality of peaches in polyethylene bags .0.02, 05 and .1㎜ thick was investigated biochemically during common and cold storage (5℃).
Weight loss was severe in control of room temperature, then followed the low temp. control except Hakuto. Marked reduction in weight loss was obtained from sealed polyethylene bags.
Medium and late varieties had a firmer texture, and thick films well maintained the firmness both at common and cold storage.
Soluble solids and titratable acidity were higher in late cultivar. Thick films(0.05 and .1㎜) at room temperature reduced the soluble solids content and titratable acidity markedly, and low temperature was more effective in maintaining the above mentioned constituents, especially control. Soluble solids content in Nunome-wase and Okubo remained constant during storage.
Thick polyethylene films induced decay and denaturation at room temperature. After six days storage, a slight off-flavor occurred in low temperature. When extended to 3 weeks, fruits became completely mealy in the control and 0.02㎜ plot.
Nunome-wase showed a high respiration rate. At low temperature, control was high, while 0.02㎜ bag lowest except Nunome-wase. At low temperature, thicker films revealed higher rate.
Total pectin of Okubo peaches did not change during 7 days storage. When bagged at room temperature, water-soluble pectin reduced rapidly. In cold storage, water-soluble pectin increased, but it decreased when shifted to the room temperature.
Flesh firmness of Okubo peaches held at room temperature had a (-) correlation with water-soluble pectin, and (+) with crude fiber. And fruits in thicker films showed better eating quality.
Further trials at various low temperatures including 0℃ with thick polyethylene films are needed.
|