Why do some people say that apples "rot in a basket"?

Children, have you ever heard the proverb "One apple is rotten, but a whole basket of apples is bad"? Often used to indicate that individual problems will affect the overall situation. In fact, this statement also has certain scientific basis. Why is it that an apple is broken and usually a basket is broken? Why? I believe many friends don't know much about it. Let's answer your question through Bian Xiao.

Immature fruit is "green", usually hard but not sweet. "Green" comes from chlorophyll, "astringent" comes from tannin, "hard" is mainly the contribution of pectin, and "not sweet" is because starch is not converted into sugar. When the fruit is about to ripen, plants will produce a gas called ethylene (CH2=CH2). It's like a signal. As soon as it appeared, all parts of the fruit seemed to hear the horn of "attack" and began to act. Some enzymes began to decompose chlorophyll and even produce new pigments, so the green color disappeared and red and yellow appeared, announcing the gradual maturity of the fruit; Some enzymes began to decompose acidic substances in fruits, which reduced the acidity of fruits. Amylase hydrolyzes starch into sugar, and the fruit becomes sweet; Pectinase began to decompose some pectin, and the fruit gradually softened; There are also some enzymes that decompose organic compounds in fruits into volatile gases with specific smells, so different fruits have different attractive smells. ...

Not only the ethylene molecules produced by the fruit itself will start the "ripening mechanism", but also the ethylene molecules from outside will have the same effect. If a fruit goes bad, the amount of ethylene it secretes will greatly increase, and the surrounding fruits will also be affected by these ethylene molecules, and they will also start the "ripening mechanism" and produce more ethylene molecules. These ethylene will promote the "ripening mechanism" of more fruits.

Many fruits in fruit shops are packed in paper or foam bags, not just for looking good. Just as the human body will react defensively when it is stimulated by the outside world, the fruit will react when it is "hurt", and the secretion of ethylene is one of them. During transportation, boxes and baskets of fruits will inevitably collide with each other. Although it is only a "minor injury", it is enough for them to produce more ethylene molecules and accelerate maturity and decay. Just like an infectious disease, if a person gets sick, everyone around him will be spared. In order to avoid "bad one, bad one", people wrap them up to reduce the probability of injury and mutual influence.

In fact, as early as ancient China, if people picked green pears, they would put them in a closed room to "incense". Incense is made from some plant materials. When smoked, it burns incompletely, and the smoke produced contains some ethylene components. Through this "ripening" method, green pears will soon become sweet and fragrant. In ancient Egypt, people would do some pruning on fruit trees at some time after figs bear fruit. Doing so can make the fruit of fig grow bigger and ripen faster. The principle is that scratching fruit trees will promote the release of ethylene molecules. Modern scientific experiments have confirmed that if the fruit trees are scratched within 16 ~ 22 days after the figs bear fruit, the speed of ethylene production will increase by 50 times within 1 hour. In the next three days, the diameter and weight of the fruit will increase by 2 times and 3 times respectively. In rural areas of China, people often cut scars on the trees after the walnuts bear fruit, and the same is true.