Inactivation kinetics of apple polyphenol oxidase in different pressure-temperature domains
Inactivation kinetics of apple polyphenol oxidase in different pressure-temperature domains
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DOI：
10.1016/j.ifset.2009.05.005
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发表时间：
2009-10-01
影响因子：
6.6
通讯作者：
Knorr, Dietrich
中科院分区：
文献类型：
--
作者：
Buckow, Roman;Weiss, Ulrike;Knorr, Dietrich
以混浊苹果汁为原料，研究了超高压和超高温对多酚氧化酶（PPO）稳定性的影响。在室温附近施加200-500 MPa或在环境压力下在45-55 ℃下进行热处理，导致鲜榨苹果汁中PPO活性增加高达65%。在0.1-700 MPa和20-80 ℃的范围内进行具有完全活化的PPO的组合压力-温度灭活实验（在400 MPa和20 ℃下处理5 min）。在所有测试的压力-温度条件下，酶失活动力学遵循2.2级反应方案。一个多项式模型被成功地应用于描述PPO失活率作为压力和温度的函数，并被用来构建压力-温度等动力学图。该图清楚地显示了在高于300 MPa的压力下压力和温度对苹果PPO失活的协同效应和在较低压力下的拮抗效应。与环境压力条件相比，在100-300 MPa下，使苹果汁中的PPO降解所需的温度提高了10-15 ℃。工业相关性：新鲜水果的高压加工在食品工业中越来越受欢迎，因为它能够在接近室温的条件下使微生物和某些酶降解，而对食品的风味或营养特性几乎没有影响。然而，需要关于工艺参数对目标反应的影响的定量数据以经济地利用该技术。本文建立了一个数学模型，描述了压力、温度和处理时间对混浊苹果汁中PPO失活的综合影响。(C)2009爱思唯尔有限公司保留所有权利。
The impact of high hydrostatic pressure and temperature on the stability of polyphenol oxidase (PPO) was studied in cloudy apple juice. Application of 200-500 MPa near room temperature or heat treatment at 45-55 degrees C at ambient pressure caused an increase of PPO activity of up to 65% in freshly squeezed apple juice. Combined pressure-temperature inactivation experiments with fully activated PPO (5 min treatment at 400 MPa and 20 degrees C) were carried out in the range of 0.1-700 MPa and 20-80 degrees C. Enzyme inactivation kinetics followed a 2.2 order reaction scheme at all pressure-temperature conditions tested. A polynomial model was successfully applied to describe the rate of PPO inactivation as a function of pressure and temperature and was used to construct a pressure-temperature isokinetic diagram. This diagram clearly showed synergistic effects of pressure and temperature on the inactivation of apple PPO at pressures above 300 MPa and antagonistic effects at lower pressures. Compared to ambient pressure conditions, temperatures required to inactivate PPO in apple juice were increased 10-15 degrees C at 100-300 MPa.Industrial relevance: High pressure processing of fresh fruits is gaining popularity in the food industry because of its ability to inactivate microorganisms and some enzymes near room temperature with little impact on flavour or nutritional attributes of the food. However, quantitative data regarding the impact of process parameters on the target reaction are required to economically utilise this technology. This paper provides a mathematical model describing the combined effect of pressure, temperature and treatment time on the inactivation of PPO in cloudy apple juice. (C) 2009 Elsevier Ltd. All rights reserved.