A pineapple, unlike many other fruits, does not continue to ripen or sweeten after picking, since it has no reserve of starch to be converted into sugar. On the contrary, it will start gradually to deteriorate; and, at best, may be stored for no more than 4–6 weeks. So the trade in fresh pineapples, other than those consumed locally or exported by air, is a matter of nice calculation; fully ripe fruit cannot be used, but the fruits picked must be as near ripe as possible.
A fully ripe pineapple can be identified by pulling out a leaf from the crown; it will come away fairly easily. The smell should be pleasantly aromatic, not suggestive of incipient fermentation. When pineapple is canned, the fruit is trimmed severely to make the rings fit the can, and also to ensure that no little bits of skin are left in the flesh. The offcuts are used for juice. The harder core is also removed, and may be made into candied pineapple.