| Summary: | 碩士 === 國立宜蘭大學 === 園藝學系碩士班 === 98 === This thesis uses the water convolvulus (Ipomoea aquatica Forsk.) at Jiaoxi hot spring area in Yilan as the material. The quality and shelf life are discussed by three variables: storage temperature, packaging and 1-methylcycloprunsealede (1-MCP).
Materials are sealed by polyethylene(PE) bag, stored at 1, 5, 10, 15, and 20℃ for 12 days respectively. The first result shows that respiration rate, yellowing and decay index increase followed with the increasing storage temperature. But the two materials stored at 1 and 5℃ show chilling injury, quality decayed rapidly as the storage time increases. What’s worse, after moving the material into 20℃ circumstances, chilling injury, respiration rate, yellowing and decay index decayed more seriously, while yellowing and decay index decay less at 10℃, and no chilling injury appears.
The water convolvulus are stored at 5, 10, and 20℃ for 12 days under the conditions of naked packaging, unsealed PE packaging, sealed PE bag, sealed PE bag containing ethylene absorber, sealed PE bag containing carbon dioxide absorber, and finally the sealed PE bag containing both carbon dioxide absorber and ethylene absorber. The results are concluded in three groups. First, for naked packaging and the unsealed PE bag, their respiration rates were lower, but weight loss and chilling injury facilitate. Second, for the sealed PE bag containing carbon dioxide absorber, the material decayed seriously and the chlorophyll degraded quickly. However, for the sealed PE bag containing ethylene absorber, both chilling injury and decay index reduced effectively, the value of L*, C*, and H。 changed less, and chlorophyll and ascorbic acid degraded less.
Water convolvulus is treated with 0, 0.1, 1 and 10 ppm respectively of 1-MCP for 4 hours at room temperature, completely sealed with PE bag at 10 and 20℃ for 16 days. Treated with 0-1ppm, its quality decayed more slowly followed by higher concentration. Treated with 1 and 10 ppm at 10℃, yellowing and decayed index decay less, the value of L*, C* and H。 changed less, and chlorophyll and ascorbic acid degraded less. This range can increase storage life. The result is the same at 20℃.
Water convolvulus, stored at 10 and 20℃ for 12 days, is treated with 0 and 1 ppm of 1-MCP for 4 hours at room temperature, under the condition of naked, the unsealed PE packaging, sealed PE bag, the sealed PE bag containing ethylene absorber. Naked packaging showed high chlorophyll but decay more slowly. However, its weight loss was much higher than weight loss with PE bag packaging, and the material loses commodity value afterwards. Surprising, the sealed PE bag maintains the best quality. This group containing ethylene absorber, decayed slowly and yellowing index reduced effectively, with the value of L*, C*, and H。 changing less, and chlorophyll degrading less.
These results suggest that a pre-storage treat, with 1-MCP of 1ppm for 4 hours at room temperature, and with the sealed PE bag containing ethylene absorber at 10℃, can best maintain the quality and extend the storage life. Storage life was 16 days in the circumstances. This approach can be a better post-harvest technology for water convolvulus cultivated by hot spring.
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