Relatively low concentration of cardamon oil vapour for controlling enzymatic browning and maintaining the quality of rambutans

Abstract

Polyphenol oxidase (PPO), peroxidase (POD) activities, brown spot diseases, and the browning incidence of rambutans play an important role after harvest. As an anti-browning and antifungal agent containing bioactive compounds, potent cardamom oil vapour was investigated at 5 and 10 μL/L inhibitors for 28 days to delay browning, reduce disease, and preserve the quality of rambutans. PPO and POD enzymes, disease incidence, colour attributes, total phenols concentrations and antioxidant were evaluated. Delayed browning with decreased PPO and POD activities, a high L*, a low chroma, a low BI value and few disease-related browning incidents were found in rambutans treated with 5 μL/L cardamom oil compared to the control group. The treated rambutans exhibited an enhanced number of total phenolic compounds and antioxidant potential and more free radical scavenging activity to prevent browning and maintain the rambutans’ physicochemical qualities for 21 days of storage, compared to the control group, which only lasted seven days without browning. The treated rambutans exhibited strong ferrous chelating activity against ABTS and DPPH radical scavenging activities. This finding showed that cardamom oil vapour could prevent browning, reduce disease, and maintain the physicochemical and microbiological quality of rambutans, which could apply to the real market shipping rambutans.