| 摘要： 本試驗首先探討蓮霧果實受低溫傷害造成寒害發生時之徵狀及指標，黑鑽石蓮霧經1℃貯藏2天即發生寒害，且隨貯藏天數增加，果皮由小點狀凹陷發展為大塊陷斑且褪色情形愈趨嚴重，果皮凹陷之發生又較褪色為早。蓮霧果實於1、15℃低溫期間呼吸率皆為微量較25℃為低，1℃貯藏3天回溫後即有呼吸高峰之異常現象產生，貯藏7天回溫後呼吸率則無法降至正常範圍，梅山蓮霧貯藏7天回溫後呼吸高峰雖較黑鑽石蓮霧低，但卻持續攀升無下降現象。蓮霧果實寒害後乙烯釋放率之結果與呼吸率相似，但其變化範圍依產地不同差異頗大。1℃貯藏7天後黑鑽石及宜蘭蓮霧因低溫造成果皮花青素含量上升，回溫1天後果皮褪色，花青素含量下降；梅山蓮霧以1℃貯藏4天後其花青素含量及較貯前低，且隨回溫時間增加而持續下降。黑鑽石及梅山蓮霧1℃貯藏7天造成回溫後果肉電解質滲漏率上升，而黑鑽石蓮霧滲漏率之增加與果皮凹陷發生幾乎同時，梅山蓮霧則於果皮凹陷出現後滲漏率才上升；宜蘭蓮霧在1、15、20℃貯藏後電解質滲漏率皆有上升現象。梅山及宜蘭蓮霧以1℃貯藏4及7天後過氧化酵素活性明顯增加，且增加現象於果皮出現凹顯之前即發生。故可得知針對黑鑽石、梅山及宜蘭蓮霧果實而言，乙烯釋放率及果皮花青素含量皆可做為寒害指標，過氧化酵素之變化可做為梅山及宜蘭蓮霧之指標。 綜合熱處理對蓮霧果實呼吸率、乙烯釋放率、果皮花青素含量、果肉電解質及果實外觀等結果，是以36℃熱風處理48小時能達到降低寒害發生之效果，處理後之果實經1℃貯藏14天後仍具有商品價值。 熱風殺蟲試驗中，43℃熱風未經加溼處理12小時，果實之果心溫度為41.2℃，予以加溼處理後果心溫度為43.3℃，加溼能加快果心增溫速度，但果實蠅死亡率卻由100％降為55％。於孵化時遮光處理則有提高蟲隻死亡之效果，43℃處理12小時可由55％提高為100％。熱風處理能降低蓮霧果實之腐爛率，但果實硬度卻為下降，果皮發生褪色且有異味產生。熱處理之果實經12℃貯藏7天後再以9℃貯藏3天，則異味減輕且果皮褪色情形亦能有所抑制。The objectives of this study were to investigate the symptoms and index of chilling injury of wax-apple when wax it was subjected to low temperature. Black-DiamondR wax-apple suffered chilling injury while it was stored at 1℃ for two days. Symptoms of injury were first appeared as small pitting on the pericarp, then developed into large sunken areas and became discolored as the day of storage increased. Sinking of the skin happened earlier than the development of discoloration. The respiration rate of wax-applestored at 1 and 15℃ was low than of at 25℃. But showed an abnormal respiration peak after stored at 1℃ for 3 days. The peak remined abnormally high after storing for 7 days at 1℃ and then back to room ttemperature. The respiration peak of wax-apple fruits, which were produced in Mei-Shan area, was lower than that of the Black-DiamondR when store for 7 days but kept increasing after returned to room temperature. The ethylene production of the injury fruit was similar to the respiration rate, but varied significantly from region to region. Anthocyanin of the fruit peel increased in Black-DiamondR as well as fruits produced in Yi-Lan when store in 1℃ for 7 days, but followed by peel discoloration and decreasing in anthocyanin content 1 day after returned to room temperature. The anthocyanin of wax-apple from Mei-Shan dropped when stored at 1℃ for 4 days, and further decreased at room temperature as time progressing. The electrolyte leakage of Black-DiamondR and Mei-Shan wax-apples was enhanced when stored at 1℃ for 7 day; the occurrence of the increasing in electrolyte leakage and peel sinking of Black-DiamondR were almost simultaneous, while the leakage of fruits from Mei-Shan was after the pitting has happened, and all wax-apple from Yi-Lan had higher leakage after stored at 1、15 and 20℃. The peroxidase activity of wax-apple fruits from Mei-Shan and Yi-Lan increased after storage at 1℃ for 4 and 7 days, and it happened prior to pitting. It seems that the ethylene production and the content of anthocyaninea can be used as indicators of chilling injury of Black-DiamondR and Mei-Shan wax-apple, as peroxidase activity is for fruits from Yi-Lan. In another experiment, Black-DiamondR wax-apple fruits treated with 36℃ hot air for 48 hours before stored at 1℃ for 14 days and this was helpful to reduce the chilling injury and kept the market value. The wax-apple’s core temperature could reach 41.2℃ after hot air（43℃）treatment for 12 hours. The raised core temperature helped to kill the larva of fruit fly. The core temperature was found to be 43.3℃ if hot air treatment was carried out under the increased humidity condition, but the mortality of the larvae was decrease from 100% to 55%. Shading was found to increase the mortality from 55% to 100%. Hot air treatment also slowed down the decay of wax-apple, but the firmness of fruits suffered, and was usually accompanied with off-flavor and discoloration, which could be relieved by storing hot air treated fruits at 9℃ for 3 days after storage at 12℃ for 7 days. |
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