Postharvest and Refrigeration Group, Department of Food Engineering, Universidad Politécnica de Cartagena, Paseo Alfonso XIII, 48, E-30203, Cartagena, Murcia, Spain; Institute of Plant Biotechnology, Universidad Politécnica de Cartagena, Plaza del Hospital s/n, Campus Muralla del Mar, E-30202, Cartagena, Murcia, Spain.
J Sci Food Agric. 2013 Dec;93(15):3863-9. doi: 10.1002/jsfa.6332. Epub 2013 Aug 21.
Watermelon juice has gained increasing popularity among consumers as a rich natural source of functional compounds such as lycopene and citrulline. However, the final quality of the juice depends significantly on its acidification, pasteurization, centrifugation and storage time and temperature. In this study, these characteristics were assessed in watermelon juice pasteurized at 87.7 °C for 20 s and stored for up to 30 days at 4 or 8 °C.
The acidifier citric acid provided an adequate sensory quality, similar to natural watermelon juice. Centrifugation and pasteurization significantly reduced the red color, bioactive compounds (lycopene, antioxidant capacity and total polyphenols) and sensory quality of the juice, particularly when the storage time was extended and a temperature of 8 °C was used (P ≤ 0.05). All treated juices were microbiologically safe for up to 30 days when stored at 4 or 8 °C. In terms of sensory acceptability, only non-centrifuged juices stored for up to 20 days at 4 °C remained above the commercial limit.
The present results suggest that using a non-centrifugation process and a storage temperature of 4 °C yields a watermelon juice that better retains its sensory and functional qualities.
西瓜汁作为一种富含番茄红素和瓜氨酸等功能性化合物的天然来源，越来越受到消费者的欢迎。然而，果汁的最终质量很大程度上取决于其酸化、巴氏杀菌、离心和储存时间及温度。本研究评估了在 87.7°C 下巴氏杀菌 20 秒并在 4°C 或 8°C 下储存长达 30 天的西瓜汁的这些特性。
酸化剂柠檬酸提供了足够的感官质量，类似于天然西瓜汁。离心和巴氏杀菌显著降低了果汁的红色、生物活性化合物（番茄红素、抗氧化能力和总多酚）和感官质量，特别是在延长储存时间并使用 8°C 温度时（P≤0.05）。所有处理的果汁在 4°C 或 8°C 下储存长达 30 天时均保持微生物安全。在感官可接受性方面，只有在 4°C 下储存不超过 20 天的非离心果汁仍高于商业限量。
本研究结果表明，使用非离心工艺和 4°C 的储存温度可使西瓜汁更好地保持其感官和功能特性。
