Acetic acid delays fresh-cut cassava browning through fine-tunning redox homeostasis

Abstract

Cassava is one of the important commercial crops in tropical and subtropical regions. However, cassava browning is an important factor restricting its postharvest storage, shelf life and quality. Therefore, suitable approaches are needed to control fresh-cut cassava browning. Acetic acid alleviates the effects of different abiotic stresses and prolongs the shelf life of food. The study aimed to study the effects of exogenous acetic acid on postharvest browning in fresh-cut cassava. The results showed that acetic acid treatment strongly delayed the discoloration during storage through reducing the activities of phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO), peroxidase (POD), and inhibiting the generation of reactive oxygen species (ROS) and malondialdehyde (MDA), as well as accelerating loss of total phenolic and flavonoid. Notably, acetic acid treatment markedly promoted the accumulation of acetic acid, delayed loss of total starch and had slight impact on jasmonic acid (JA). In addition, JA treatment also delayed discoloration during cassava storage. These findings suggested that the delay of cassava browning via acetic acid treatment could be attributed to maintenance of redox homeostasis by modulating repair of oxidatively damaged proteins, providing a new way to prevent the browning of fresh-cut cassava and elucidates the anti-browning mechanism of acetic acid treatment.