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The effects of immersion temperature and time, sugar concentration, and salt addition on water loss,solid gain, molality and rate parameter of green pumpkins during osmotic dehydration were analyzedby a response surface methodology, and osmotic dehydration effects on browning reduction of air-driedgreen pumpkins were also evaluated. The water loss, solid gain and molality are fast in the beginning ofprocess and then increase slowly during remainder of the process. After 20 min of immersion time,water loss and solid gain of 100 g wet green pumpkin at 80oC, 60oBrix sugar solution with 0, 2, 4% saltaddition were 50.5, 54.8 and 58.6 g water loss and 10.4, 10.0 and 9.7 g solid gain, respectively. Based onthe coefficients of determination, all second degree polynomial regression models were highly fitted tothe experimental data at the level of 0.01%. Rate parameter, K, values were increased as the immersiontemperature and sugar concentration increased. Browning degree was decreased as the immersiontemperature, time and salt concentration increased. Minimum browning degree of dried greenpumpkins (O.D. = 0.076) could be achieved using 80oC binary solutions (40oBrix sugar solution with 4%salt addition) with 20 min of immersion time compared to control (O.D. = 0.364) and 80oC blanchingwith 20 min of immersion time (O.D. = 0.122).