为有效控制双孢蘑菇褐变,研究pH值、温度、底物浓度以及抑制剂对双孢蘑菇的多酚氧化酶(polyphenoloxidase,PPO)活性的影响。结果表明:以邻苯二酚为底物,双孢蘑菇PPO最适反应pH6.8,最适反应温度20℃,最适反应底物浓度为0.06mol/L,米氏常数Km为0.1072mol/L。采用计算机图像处理技术对双孢蘑菇褐变程度进行定量检测,得出对双孢蘑菇贮藏保鲜效果较好的褐变抑制剂及其最佳配比为0.30mmol/L半胱氨酸、0.06%抗坏血酸、0.05%乙酸。
In order to effectively inhibit enzymatic browning in Agaricus bisporus,effects of pH values,temperature,substrate concentration and inhibitors on polyphenol oxidase(PPO) activity from Agaricus bisporus were studied.The results showed that the optimum pH value and temperature for PPO activity from Agaricus bisporus were 6.8 and 15-20℃ using pyrocatechol as substrate.The Michaelis constant of PPO was Km = 0.1072 mol/L.Computational imaging analysis showed that mixture of 0.30 mmol/L sodium sulfite,0.06% ascorbic acid and 0.05% acetic acid had effective inhibition on enzymatic browning in Agaricus bisporus.