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Abstract: The effect of ultraviolet irradiation combined with chitosan coating on fresh jujube under ambient temperature was investigated. In the first period, the jujubes were irradiated for 4, 6, 8, 10 min at 253.7 nm ultraviolet, or coated with 1%, 1.5%, 2% and 2.5% of chitosan, respectively. In the second period, the jujubes were firstly irradiated 6 min, and then coated with 1.5% of chitosan. The result showed that combined treatment could reduce decay incidence of jujubes and restrain increase of respiration rate, weight loss, malonaldehyde content and electrolyte leakage of jujubes. Furthermore, the activities of superoxide dismutase, peroxidase, and catalase were maintained at higher level, and the decrease of ascorbic acid and chlorophyll was restricted. The present data indicated that treating post-harvest jujubes with ultraviolet irradiation combined with chitosan coating was an effective method, and might be considered in commercial application for preservation of postharvest fruit. [Copyright &y& Elsevier]

Abstract: The effect of carbon monoxide (CO) on enzymatic browning of fresh-cut lotus root slices in relation to phenolic metabolism was investigated. Fresh-cut lotus root slices were fumigated with CO gas at 75, 125, 175 or 225 μL/L for 10, 20, 30 or 40 min, and then stored for 8 days at 5 °C. Changes in color, total phenol, malonaldehyde (MDA), and activities of phenolic-associated enzymes including polyphenol oxidase (PPO), peroxidase (POD) and phenylalanine ammonialyase (PAL) in lotus root slices were measured. The results indicated that fumigating fresh-cut lotus root slices with 175 μL/L of CO for 20 min delayed browning and inhibited increase of MDA. Besides, total phenol also showed higher level from 0 to 4 days. Furthermore, the activities of PPO and POD were inhibited, but PAL activity was increased. The present data suggests that CO has the potential to inhibit browning and maintain quality of fresh-cut lotus root slices. [Copyright &y& Elsevier]