Departamento de Ingeniería Química, Alimentos y Ambiental, Universidad de las Américas Puebla, ExHda Santa Catarina Mártir s/n, San Andrés Cholula, Puebla 72810, México.
J Agric Food Chem. 2024 Jun 26;72(25):14294-14301. doi: 10.1021/acs.jafc.3c08888. Epub 2024 Jun 14.
Enzymatic browning in fruits and vegetables, driven by polyphenol oxidase (PPO) activity, results in color changes and loss of bioactive compounds. Emerging technologies are being explored to prevent this browning and ensure microbial safety in foods. This study assessed the effectiveness of pulsed light (PL) and ultraviolet light-emitting diodes (UV-LED) in inhibiting PPO and inactivating ATTC 25922 in fresh apple juice ( var. Red Delicious). Both treatments' effects on juice quality, including bioactive compounds, color changes, and microbial inactivation, were examined. At similar doses, PL-treated samples (126 J/cm) showed higher 2,2- diphenyl-1-picrylhydrazyl inhibition (9.5%) compared to UV-LED-treated samples (132 J/cm), which showed 1.06%. For microbial inactivation, UV-LED achieved greater reduction (>3 log cycles) and less ascorbic acid degradation (9.4% ± 0.05) than PL. However, increasing PL doses to 176 J/cm resulted in more than 5 log cycles reduction of , showing a synergistic effect with the final temperature reached (55 °C). The Weibull model analyzed survival curves to evaluate inactivation kinetics. UV-LED was superior in preserving thermosensitive compounds, while PL excelled in deactivating more PPO and achieving maximal microbial inactivation more quickly.
酶促褐变是由多酚氧化酶（PPO）活性引起的，会导致果蔬颜色变化和生物活性化合物损失。目前正在探索新兴技术以防止褐变并确保食品的微生物安全性。本研究评估了脉冲光（PL）和紫外发光二极管（UV-LED）在抑制 PPO 和灭活 ATCC 25922 方面的效果在新鲜的红富士苹果汁（var. Red Delicious）中。两种处理方式对果汁质量的影响，包括生物活性化合物、颜色变化和微生物失活，都进行了评估。在相同剂量下，PL 处理的样品（126 J/cm）显示出比 UV-LED 处理的样品（132 J/cm）更高的 2,2-二苯基-1-苦基肼抑制率（9.5%），后者为 1.06%。对于微生物失活，UV-LED 实现了更高的减少（>3 对数周期）和较少的抗坏血酸降解（9.4%±0.05），而 PL 则相反。然而，将 PL 剂量增加到 176 J/cm 会导致 减少超过 5 个对数周期，表明与最终达到的温度（55°C）有协同作用。Weibull 模型分析了存活曲线以评估失活动力学。UV-LED 更擅长于保存热敏化合物，而 PL 则在失活更多的 PPO 和更快地实现最大微生物失活方面表现出色。
