You can eat. Bananas grow in tropical and subtropical areas and really have no frost resistance. If the green banana is put in the refrigerator, its ripening mechanism will be destroyed. When it is brought to room temperature, it is difficult to continue to mature even if ethylene is given. Therefore, green bananas really can't be put in the refrigerator. But if the banana is ripe, it will continue to mature and deteriorate at room temperature. If it is put in the refrigerator, the activity of the enzyme will be reduced, and the speed of further ripening of bananas will also be reduced. Therefore, ripe bananas can be stored in the refrigerator for a longer time. However, this "preservation" means that the banana pulp can keep its flavor and taste, but the banana skin will still turn black. This is because the cells in banana peel are easily destroyed by low temperature, and phenols and polyphenol oxidase can meet.