Studies on anti-browning of coconut (Cocos nucifera L.) fruit

Abstract

The effects of polyphenol oxidase (PPO) and peroxidase (POD) on the phenolic content in coconut (Cocos nucifera L.) fruit during processing and storage were studied using spectrophotometry and high-performance liquid chromatography. Polyphenol oxidase was able to oxidize monophenol, diphenol and polyphenol. The main phenolics present in the coconut peel (epicarp and part of the mesocarp) were chlorogenic acid and dopamine. After treatment with heat and sodium sulphate + citric acid, there was significant inhibition in the activities of PPO and POD and significant reduction in the content of phenolics, which was coincident with a milky white colour and good quality of fruit when stored for 40 days at 10ºC. The result of the study showed that it is possible to control browning of coconut fruit by inhibiting the activities of PPO and POD on phenolics during processing, transportation and storage.