Summer is a tough time for lovers of plantains and bananas. If they are left out of the refrigerator, they take very little time to spoil. However, if they get inside they will last longer, but in exchange for a very unpleasant black skin and a little less flavor. All a punishment that is basically due to its origin.
Bananas are tropical fruits and as such do not tolerate cold well. But of course, like good climacteric fruits, they continue to ripen once they are picked. This happens much faster with the heat and forces us to make uncomfortable decisions.
Do we buy only a few bananas to avoid losing them for a over-ripening Or do we risk taking them black and with less flavor? Actually, there is no one answer better than the other. In the Fridge they have that little drawback, but they are no less healthy or nutritious. It all depends on our tastes and our individual needs. But, leaving that aside, let’s see the reasons why the skin of bananas turns black in the fridge.
Ethylene and climacteric fruits
To a large extent, the ripening of fruits is mediated by a gas generated by them, called ethylene. This happens in all. However, the levels at which it is released depend on whether they are fruits non-climacteric or climacteric. The former produce stable and low levels of ethylene. On the other hand, in climacteric cells, ethylene is generated in greater quantity and continues to do so. after harvest.
Therefore, if we pick non-climacteric fruits before they ripen, they will no longer ripen. It is, for example, the case of grapes or cherries. Instead, we can collect bananas totally green and we will see how they continue to mature later. This is because they are climacteric.
In addition, it is the reason why, if we do not want the bananas to ripen too quickly, we should not leave them inside a closed bag. In that case, the ethylene around them will be concentrated and they may pass from zero to one hundred too fast. Of course, the cold can slow down the ripening of bananas. For that they are put in the fridge. But the already mentioned problem of darkening of the skin occurs. What can it be due to?
Causes of Black Skin on Bananas
Interestingly, when bananas ripen they tend to darken. But when they are put in the fridge to slow down the ripening, they darken even more. This is because, in reality, they are different mechanisms. You just have to see that if we open the inside of the fridge banana, it is much less ripe than one that has been left outside.
In the case of black skin in the fridge it is because the cold breaks down the cell walls of said skin, facilitating the release of certain substances, such as a protein called polyphenol oxidase. In addition, when this happens, it comes into contact with substances called phenolic compounds and oxidizes them, giving rise to a dark coloration.
This cell rupture also occurs when the fruit receives a hit. Therefore, it is normal that when the bananas fall to the ground they get blacker. But of course, generally that happens only in the area where the hit took place. In this case, since the cold is distributed throughout the fruit, the skin darkens completely.
But it’s not a bad thing. At most, the flavor can be altered by the slowdown in ripening, but the fact that the skin is black does not make it dangerous to eat the banana. It is more a matter of aesthetics than health or nutrition. Definitively, as we have already seen, it is nothing more than a matter of taste.