3.2. Effects of chitosan coating on fruit quality
As shown in Fig. 3, Fig. 4, Fig. 5 and Fig. 6, eating quality in longan fruit decreased as the period of storage increased, while colour grade, weight loss, and disease development increased. After 30 days of storage, the initial bright colour of the control fruit had largely disappeared, and about 30% of the fruit had begun to rot. Compared with the control, the fruit treated with 2% chitosan remained a bright colour and about 95% of the treated fruit did not rot until 30 days after storage. However, disease development significantly increased as storage time was extended to 40 days. In this study, increasing concentrations of chitosan were generally more effective for longer storage period. No off-flavours in chitosan-treated fruits were detected because the low temperature of storage reduced physiological metabolism.