Summary: | 碩士 === 國立中興大學 === 園藝學系所 === 97 === Post harvest bamboo shoots (Dendrocalamus latiflorus Munro) are characterized by an increase in respiration and ethylene production, thus resulting in the rapid damage of bamboo shoots. The purpose of this study was to investigate the postharvest physiology of bamboo shoots and seek for the most appropriate handling technique to extend shelf life. This study examined the following postharvest handling techniques: temperature control, heat treatment, chemical treatmemt (sodium hypochlorite, 1-MCP, and AVG), and packaging. Firstly, after harvest, respiration and ethylene production in bamboo shoots increased with temperature. However, bamboo shoots stored at 1℃, 3℃, and 6℃ resulted in the following: good appearance; lower firmness and cut force; decreased PPO, POD, and PAL activity; and decreased lignin and cellulose content. On the other hand, storage at 1℃ and 3℃ caused chilling injury after 19 days. The results showed that 6℃ is optima storage temperature of bamboo shoots. Secondly, all hot-water treatment experiments, whether at ambient temperature for 1 day, or at 6℃ for 7 days then ambient for 1 day (ambient temperature simulated a one-day marketing period), showed very little browning on the cut surface of bamboo shoots. The best result was found to be hot-water treatment at 70℃ for 30 seconds for storage at both ambient temperature or 6℃. Thirdly, although the chemical treatment of sodium hypochlorite did decrease the browning of the cut surface of bamboo shoot, this treatment is not recommended because of food safety concerns. 1-MCP and AVG treatment caused rapid increase in ethylene production and also increased the appearance of browning on the cut surface area of bamboo shoots during the 12 hours ambient temperature storage. Finally, a one PE bag (0.03㎜) packaging treatment retained the best color of bamboo shoot during storage at 15℃ for 4 days. However, the one PE bag packaging treatment sped up respiration and ethylene production on the 4th day of storage at 15℃. Besides the above mentioned postharvest handling techniques, storage postures were an important factor to maintaining the quality of bamboo shoots. Bamboo shoots storage has three postures: 1) natural, spear upward, 2) reverse, spear downward, and 3) horizontal, spear sideways. The horizontal posture showed minimum browning during storage at 6℃ for 4 weeks. In conclusion, the most effective treatment to extend the storage life of bamboo shoots was found to be heat treatment at 70℃ for 30 secs, packaging with one PE bag( 0.03㎜), and storage at 6℃ with horizontal posture. This treatment extended storage time up to 4 weeks and when the bamboo shoots were returned to ambient temperature for 12 hours, there was no reduction of the sale value of the shoots.
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