학술논문

Predicting sugar content of candied watermelon rind during osmotic dehydration
Document Type
article
Source
Food Science and Technology. December 2018 38(1)
Subject
vacuum
solid gain
dehydration efficiency
mass transfer kinetics
response surface methodology
Language
English
ISSN
0101-2061
Abstract
Watermelon rind, comprising 35% of the fruit’s total mass, usually discarded due to its unappealing flavor and lack of sweetness. In this study, candied watermelon rind was prepared through osmotic dehydration at vacuum (VOD) and atmospheric pressure (OD). The effects of independent variables (sucrose concentration, immersion time and temperature) on the dependent variables, including solid gain (SG) and water loss (WL) of watermelon rind, were evaluated using multiple response surface methodology. The SG and WL increased with the increasing sucrose concentration, immersion time and temperature for both VOD and OD, but VOD greatly increased the mass transfer rate. The kinetic constants were obtained by fitting the data of SG and WL to the Fick’s diffusion model. The VOD had higher kinetic constants and dehydration efficiency indices than that of OD. Besides, the mass transfer model and RSM model were statistically compared by the coefficient of determination, root mean square error and absolute average deviation, based on the validation data set. The RSM and mass transfer models provide information about the osmotic dehydration for predicting the sugar content of candied product, and helping the designers and researchers find the best design parameters and the most effective process conditions.