Drying kinetics of jabuticaba pulp by regression models

Abstract Jabuticaba tree is native to the Atlantic Forest in Southern Brazil, and its fruit is widely consumed in the fresh form, but it is highly perishable, requiring conservation techniques. The aim of this study was to describe the drying kinetics of jabuticaba pulp at temperatures of 50 and 60°C, comparing the Henderson, Simple Three-Parameter Exponential, Lewis, Thompson, Fick and Wang and Sing regression models and estimating the Absolute Drying Rate (ADR) for the best model. Parameters were estimated using the SAS software. The evaluation of the quality in the adjustment and selection of models was made based on the adjusted determination coefficient, Residual Standard Deviation and Akaike Information Criterion. Models presented good adjustment to data, and the Lewis model was the most suitable to describe the drying kinetics of jabuticaba pulp at temperatures of 50 and 60°C, with drying rate of 0.000063 and 0.000082 g of water/s respectively. ADR indicated that in one third of the drying time, 70% of moisture loss occurred at both temperatures and after this period, there was a deceleration of moisture loss until stabilization, when equilibrium moisture content is reached.

摘要：嘉宝果（Jabuticaba）树原产于巴西南部大西洋森林，其果实多以鲜食方式消费，但极易变质腐烂，亟需采用保鲜处理技术。本研究旨在探究50℃与60℃条件下嘉宝果果浆的干燥动力学特性，对比亨德森（Henderson）、三参数简单指数、刘易斯（Lewis）、汤普森（Thompson）、菲克（Fick）及王与辛格（Wang and Sing）等回归模型，并基于最优模型估算绝对干燥速率（Absolute Drying Rate, ADR）。本研究采用SAS软件完成参数估算工作，模型拟合效果评估与选型依据调整决定系数、残差标准差及赤池信息准则展开。结果显示，各模型均能较好适配实验数据，其中刘易斯模型最适用于描述50℃与60℃下嘉宝果果浆的干燥动力学过程，对应干燥速率分别为0.000063与0.000082 g/s。绝对干燥速率分析表明，在干燥时长的三分之一阶段，两种温度下均完成了70%的水分流失；此后水分流失速率逐渐放缓，直至达到平衡含水率后趋于稳定。