Changes in cashew apple juice treated with optimum thermosonication during storage

Abstract

This study aimed to determine the effects of the thermosonication parameters (300 J/g and 60°C) on polyphenol oxidase-(PPO) inactivation and some quality attributes. The change in quality parameters (residual PPO activity, total phenolic, total carotenoid compounds, ascorbic acid (AA), color, and microbiological load) of optimally thermosonicated juices were evaluated during the storage for three months. The residual PPO activity, and total color difference (∆E*) increased, while total phenolic, total carotenoid and AA contents decreased significantly during the storage (4°C, 90 days). Residual PPO activity was 16.87% at the beginning of storage, and 58.4% at the end of storage. The total carotenoid content decreased by 35% at the end of the storage. Gallic, syringic, caffeic, chlorogenic acids, and naringenin increased respectively by 125%, 113%, 80%, 31%, and 60% after treatment. The total mesophilic aerobic bacteria and yeast-mold load in the stored juices increased at certain range during storage. The cashew apple juice was consumable at the end of the storage due to acceptable level of the microbial increases. Finally, optimum thermosonication applied to juices did not differ significantly in terms of sensory characteristics compared to the control.

Keywords

• Cloudy cashew apple juice
• Thermosonication
• Storage
• Residual polyphenol oxidase-(PPO)
• Bioactive compounds
• Total color difference