Bai Jinhe, Hagenmaier Robert D, Baldwin Elizabeth A
Citrus and Subtropical Products Laboratory, US Department of Agriculture, 600 Avenue S, NW, Winter Haven, Florida 33881, USA.
J Agric Food Chem. 2002 Dec 18;50(26):7660-8. doi: 10.1021/jf020543n.
Five experimental coatings with different resistance to gas exchange were used with freshly harvested and 20-week commercially stored apples of Delicious, Fuji, Braeburn, and Granny Smith varieties. The coated or noncoated apples were held at 20 degrees C for up to 4 weeks. The gas partial pressures inside the fruits with the various coatings ranged from 1 to 25 kPa CO(2) and from 20 to 1 kPa O(2). Volatile evaporation rates were measured, as also were the volatiles compositions in the fruit. The coatings with intermediate gas resistance (carnauba-shellac mixture and candelilla) gave intermediate values of CO(2) and O(2) in the internal atmosphere in Delicious, Fuji, and Braeburn apples and the highest concentrations of butyl acetate and 2-methylbutyl acetate in the fruits. The coatings with the highest gas resistance (shellac and shellac-protein) caused high internal CO(2) and low O(2), resulting in anaerobic fermentation in Braeburn and Granny Smith apples and relatively high amounts of low-molecular-weight ethyl esters trapped within the fruit. A small portion of the alcohols were evaporated from fruits compared to esters, this attributed to their high Henry's law coefficients.
对新收获的以及经过20周商业储存的美味、富士、澳洲青苹和布瑞本品种苹果，使用了五种具有不同气体交换阻力的实验性涂层。将涂有或未涂有涂层的苹果在20摄氏度下保存长达4周。带有各种涂层的果实内部的气体分压范围为1至25千帕二氧化碳以及20至1千帕氧气。测量了挥发性物质的蒸发速率以及果实中的挥发性物质成分。具有中等气体阻力的涂层（巴西棕榈蜡 - 虫胶混合物和小烛树蜡）使美味、富士和布瑞本苹果内部大气中的二氧化碳和氧气值处于中等水平，并且果实中乙酸丁酯和乙酸2 - 甲基丁酯的浓度最高。具有最高气体阻力的涂层（虫胶和虫胶 - 蛋白质）导致内部二氧化碳含量高而氧气含量低，致使布瑞本和澳洲青苹苹果发生厌氧发酵，并使相对大量的低分子量乙酯被困在果实中。与酯类相比，一小部分醇类从果实中蒸发，这归因于它们较高的亨利定律系数。
