| Pineapple(Ananas comosusr) is rich in fructose, glucose, amino acids, organic acids, vitamins and other nutrients. In order to protect the fresh-cut pineapples from browning and infection by microorganisms easily, "Ananas comosusr.Yellow Mauritius" was used as the experi-mental material, and the study was focused on the critical steps in the process and storage of the fresh-cut pineapple, including maturity, disinfection method and color protect technique. The research also aims to study other influences of these critical steps could bring to the fresh-cut pineapples and the mechanism behind these influence. The results are as follows:The browning is delaying as the maturity increasing, which means that the browning is directly affected by maturity; while the hardness and weight loss are increasing as the maturity increasing. Results shows that the fresh-cut green pineapple have a high hardness, while the fresh-cut partly yellow pineapple keep the content of vitamin C and total soluble solids (TSS) very well. Afterripening increase the content of reduced sugar in fresh-cut green pineapples. The content of vitamin C and total soluble solids (TSS) on fresh-cut partly yellow pineapples is higher than that in the green pineapples and yellow pineapples. The maturity of pineapples has a little influence on acid content of pineapples. The result shows that partly green of pineapple is the optimum maturity for fresh-cut.It has been found that no coliform, during the storage period, is found in the fresh-cut pineapples irradiated for more than 15S by UV-C, and the number of mold and yeast are decreased tremendously after treated by 60S and 90S UV-C irradiation during the storage. The best inhibitory effect of irradiation on the total number of colonies appeared at 60S. After treating by UV-C, both the declining rate of hardness, TSS, sugar content and rotting rate and the increasing rate of acid content are lower than that of the reference; however, the content of vitamin C is decreased tremendously and the browning of fresh-cut pineapples appears earlier.The study shows that the decrease rate of Vc in the pineapples coated after irradiation of UV-C is lower than that of Vc in pineapples treated by UV-C directly. During the storage period, the coating after UV-C irradiation on pineapples can decrease both the declining rate of sugar content and the increasing rate of acid content. The coating has a little effect on the weight loss and TSS. During the storage period, erythorbic acid (0.75%), edible konjac coating (1%) and mixture coating (0.75%EA+1% edible konjac+0.75% chitin)can protect pineapples'color very well and decrease the browning rate of pineapples. Applies EA and coating on pineapples can decline the rotting degree of the fresh-cut pineapple and maintain a good looking. After coating, both the decrease rate of hardness, TSS, content of sugar and vitamin C and the increase rate of acid content are declined. The active of PPO, POD, and PAL are inhibited after treated by coating with erythorbic acid, chitin and konjac, respectively. The mixture coating of erythorbic acid, chitin and konjac assembles advantages of all three kinds of coating, which shows obviously inhibiting the increase of PPO, POD and PAL activities and the declining of the total phenolic and flavanoid contents.
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