梨质地变化规律与动力学模型

为了研究梨在采后贮藏过程中质地变化规律以对可食用期评估，实验测定了‘黄金’、‘玉冠’和‘丰水’3 个品种梨在贮藏过程中泰勒（Magness-Taylor，MT）硬度、果肉硬度、果肉弹性率和感官总体可接受度的变化，并建立了质地参数变化的动力学模型。结果表明：MT硬度、果肉硬度、果肉弹性率总体上均随贮藏时间延长逐渐降低，但果肉弹性率对贮藏时间变化的灵敏性优于MT硬度和果肉硬度，且果肉弹性率与感官总体可接受度的相关性更强；采用零级和一级动力学模型、Logistic模型和威布尔模型对各质地参数拟合，结果均是威布尔模型的拟合结果最佳；通过威布尔模型和感官评定，得到‘黄金’、‘玉冠’和‘丰水’梨的MT硬度分别低于14.762、10.411 N和7.255 N，果肉硬度分别低于8.215、7.438 N和5.181 N，果肉弹性率分别低于4.571、5.572 N/mm和3.609 N/mm后不具备商品价值，不建议食用。研究结果可为梨的贮藏和食用提供指导依据。

Kinetic Analysis and Modelling of Changes in the Texture of Pear Fruit during Postharvest Storage

Three pear varieties (Pyrus pyrifolia cv. ‘Whangkeumbae’, ‘Yuguan’, and ‘Hosui’) were used to investigate the textural changes of pear fruit during storage and evaluate their storage lives. Magness-Taylor (MT) firmness, flesh firmness and stiffness were measured by puncture test, and overall acceptability was measured by sensory evaluation. Kinetic models were established for texture parameters of pear fruit. The results showed that MT firmness, flesh firmness and stiffness generally decreased with storage time, and stiffness was more sensitive to storage time than MT firmness and flesh firmness. In addition, stiffness had better correlation with overall acceptability than MT firmness and flesh firmness. The zero-order and first order kinetic models, logistic model and Weibull model were established for each texture parameter. The best results were obtained by the Weibull model. Based on the Weibull model and sensory evaluation,‘Whangkeumbae’, ‘Yuguan’ and ‘Hosui’ lost commodity value and should not be eaten when their MT firmness were lower than 14.762, 10.411 and 7.255 N, flesh firmness were lower than 8.215, 7.438 and 5.181 N, and stiffness were lower than 4.571, 5.572 and 3.609 N/mm, respectively. These results can provide useful guidance for pear storage and consumption.