‘旭’蘋果在五種不同貯藏方法中之品質變化

Changes in the Quality of 'Mclntosh' Apples under Five Different Storage Conditions

本研究以三年時間重複採用五種方法貯藏‘旭’品種之蘋果（Malus domestica Bork.），以比較不同方法對保持果實品質之效果。五種方法包括0°C空氣中冷藏、傳統氣調貯藏（CA貯藏）、高二氧化碳CA貯藏、快速CA貯藏、及低乙烯CA貯藏。其中四種CA貯藏均採用混合氣體流通式模擬CA方式試驗。‘旭’蘋果在空氣中冷藏一個月內就失去理想的硬度（理想硬度為≧58N），三個月後出現褐心病、褐皮病、蒂端崩潰等貯藏障礙。相同的蘋果在傳統CA貯藏中也一個月內喪失理想的硬度，但貯藏三個月後硬度雖已不理想還算顯著優於空氣中冷藏者。其他三種改良CA貯藏方法，即高二氧化碳CA、快速CA及低乙烯CA依次能保持‘旭’蘋果理想硬度1～2個月、1～4個月及3～6個月，依試驗年份而有差異。以上四種CA貯藏方法均可維持‘旭’蘋果最低可接受之硬度（≧45N）至少4～6個月，而且未發生貯藏障礙。‘旭’蘋果之糖度在貯藏中變化很小，但酸度則逐漸下降。因為五種貯藏方法對糖度及酸度保持效果之差異不顯著，貯藏方法對品質之影響主要決定於硬度的保持。綜合判斷保持‘旭’蘋果之效力優劣，依次為低乙烯CA、快速CA、高二氧化碳CA、傳統CA及空氣中冷藏。此種次序除高二氧化碳CA與傳統CA之間差異較大之外，其餘任何相鄰兩種方法間之差異都不大，但相隔兩種方法間之差異則相當顯著。

McIntosh' apples (Malus domcstica Bork.) were stored under five different conditions in three consecutive storage seasons. The five conditions were cold air storage, regular CA, high-carbon doxide CA, rapid CA, and low-ethylene CA. A flow-through simulated CA storage method was used in all CA treatments. Fruit quality, including flesh firmness, soluble solid content, acidity, and the presence of storage disorders were evaluated before and after storage. The fruit lost its desirable firmness of ≧58N within one month and developed storage disorders, such as brown core, scald, and stem-end breakdown, after three months of storage in 0°C cold air. Similar fruit also lost its desirable firmness within one month in regular CA, but the fruit in regular CA were somewhat firmer than the fruit in cold air after ≧3 months of storage. High-carbon dioxide CA, rapid CA, and low-ethylene CA were able to maintain the desirable flesh firmness of 'McIntosh'’ apples for 1 to 2 months, 1 to 4 months, and 3 to 6 months, respectively, depending on storage seasons. All four CA storage conditions were able to maintain the fruit above its minimum required firmness of ≧45N and free from storage disorders for at least 4 to 6 months. The soluble solid content of the fruit had little change in storage, but the acidity declined gradually. Since the five storage conditions did not cause a significant difference in soluble solid content or acidity changes, the treatment effect on the fruit quality was mainly determined by the effect on fruit firmness retention. The overall effectiveness in preserving 'McIntosh' apple quality of the five storage conditions was in the following order: low-ethylene CA > rapid CA > high-carbon dioxide CA > regular CA > cold air storage. The difference between high-carbon dioxide CA and regular CA was almost always large and significant. Other than this fact, the differences between adjacent two treatments in the above-mentioned order list were generally small, but the differences between distant two treatments were often significant.