Papaya

One reason why papayas don’t need to be refrigerated is because they continue to ripen even after being harvested. Unlike other fruits that may start deteriorating once picked, papayas undergo a process called ethylene ripening. This means that they continue to soften and sweeten at room temperature, making them even more delicious over time.
In addition, refrigerating papayas can adversely affect their texture. When exposed to cold temperatures, the starches within the fruit break down into sugars more slowly, resulting in a mushy texture rather than the desired firmness.