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When Good Bananas Go Bad
当香蕉开始腐坏

Have you ever wonder why bananas seem to go bad so quickly? And why do they develop those brown spots?
你是否曾好奇过为什么香蕉特别容易坏掉，并长出棕色的斑点呢？

Well, those spots are a natural part of the ripening² process. You see, just like all fresh produce, your bananas are alive. They’re taking in oxygen to help them convert sugars into energy, and releasing carbon dioxide. This process is called respiration³.
其实那些斑点是香蕉成熟过程中的自然组成部分。你知道，和所有的新鲜果蔬一样，香蕉是“活”的。它们不断地吸收氧气来并把糖类转换成能量，释放出二氧化碳。这一过程称为呼吸作用。

The quicker a fruit or vegetable respires, the quicker it ripens⁴. For most fruits, the respiration rate slows down after the initial growth stage and the fruit ripens slowly. The growth and ripening process of bananas, however, is different. Although at first the banana’s respiration slows down too, when it’s ready to ripen¹, the banana’s pulp⁵ releases a chemical that increases respiration. This converts the starches⁶ in the banana to sugars and gives it its fabulous⁷ taste.
果蔬的呼吸作用越快，则成熟得越快。呼吸作用会在生长初期过后减弱，水果的成熟过程也会变慢。然而，香蕉的生长和成熟过程却并不是这样。尽管一开始香蕉的呼吸作用也会减弱，但当它快要成熟时，香蕉的果肉会释放出一种化学物质促使呼吸作用增强。在这一过程中香蕉会把体内的淀粉转化成糖，从而变得美味无比。

With all this respiration, the banana eventually processes all the starches available. And that’s when it begins to die. Those brown .
正是这种呼吸作用使香蕉最终把所有的淀粉转化成糖。而这也是它开始变质的时候，那些棕色的斑点就是它腐烂的标志。