Plums

One reason why plums don’t need to be refrigerated is because they have a relatively high sugar content and low water content. These qualities make them less prone to spoilage compared to other fruits that are juicier and more perishable. Plums can stay fresh at room temperature for several days without spoiling, making them convenient snacks for people on the go.
It’s also worth noting that chilling plums can affect their taste and texture. Cold temperatures can cause the flesh of the plum to become mealy or grainy instead of juicy and sweet.