Hashemi Seyed Mohammad Bagher, Roohi Reza
Department of Food Science and Technology, Faculty of Agriculture, Fasa University, Fasa, Iran.
Department of Mechanical Engineering, Fasa University, Fasa, Iran.
Food Sci Technol Int. 2022 Apr;28(3):247-256. doi: 10.1177/10820132211009442. Epub 2021 Apr 14.
The effect of ultrasound treatment (100 W, 30 kHz; 50 and 100% amplitudes) on inactivation of and in pomegranate juice and shelf life of the juice during storage at different temperatures (5, 15 and 30 °C) for 30 days was modeled using predictive and thermodynamics models. The Baranyi and square root type models were implemented to determine the growth rate of microorganisms. It was predicted that the minimum growth temperature () of increased by increasing sonication amplitude, however, the of was not function of sonication amplitude. The predicted shelf life was shown to be in good agreement with the measured sensorial shelf life. Increasing the temperature from 5 to 35 °C, reduced the shelf life from 17.5 to 3.5 days for and from 15 to 5 days for . Moreover, for , the activation energy () decreased from 43.4 to 27.5 kJ/mol by increasing the amplitude, while no significant change was observed for . Besides, thermodynamics properties of the shelf life such as enthalpy (), entropy () and Gibbs free energy ( were proven to be suitable measures to determine the microbial spoilage reaction.
采用预测模型和热力学模型，模拟了超声处理（100 W，30 kHz；50%和100%振幅）对石榴汁中 和 的失活作用以及在不同温度（5、15和30 °C）下储存30天期间果汁货架期的影响。运用Baranyi模型和平方根型模型来确定微生物的生长速率。据预测，随着超声处理振幅的增加， 的最低生长温度（ ）升高，然而， 的 并非超声处理振幅的函数。预测的货架期与实测的感官货架期显示出良好的一致性。将温度从5 °C提高到35 °C， 的货架期从17.5天缩短至3.5天， 的货架期从15天缩短至5天。此外，对于 ，通过增加振幅，活化能（ ）从43.4 kJ/mol降至27.5 kJ/mol，而对于 未观察到显著变化。此外，货架期的热力学性质，如焓（ ）、熵（ ）和吉布斯自由能（ ）被证明是确定微生物腐败反应的合适指标。
