JoAnne Skelly: When to harvest apples

My two apple trees are loaded with fruit this year. One is an old tree of unknown variety and the other is a red delicious. The old tree is dropping apples all over the place. Some have a coral-colored blush; others are still greenish yellow. The coral tinted ones are definitely ready, but the others aren’t, probably because apples in the sun ripen more quickly than apples growing in the interior of the tree. However, the red delicious apples are ripening later.

According to University of Minnesota Extension: “As apples ripen, their starch converts to sugar. If you bite into an unripe apple, the starch will create a feeling on your tongue that some may describe as dry, sticky, or astringent. Unripe apples may also be quite tart. If you taste an apple like this, it is not a fault of the variety — the apple is meant to be left alone to ripen longer.” The flavor of an apple is the best indicator of ripeness. Pick one and try it.

I don’t use the apples that have dropped on the ground, whether for fresh eating, juicing, baking or canning because they can be contaminated with patulin.

“Patulin is a mycotoxin produced by molds like Penicillium… when apples or other fruits are injured. The toxin is heat-stable, meaning it is resistant to heating, even at pasteurization temperatures. You cannot see or smell or taste the toxin, so it is not possible to know if it is present without laboratory testing. Patulin has been shown to cause serious illness in animals and humans, especially to the nervous systems and might cause problems with blood flow, nausea, vomiting and other symptoms” (UMN).

Apples continue to ripen off the tree. Since I prefer crisp rather than mealy apples, particularly with the red delicious, I like to pick them before they are completely ripe and put them in the refrigerator to finish ripening. This makes their texture much firmer than store-bought apples. Commercial orchards actually harvest apples one to two weeks before peak ripeness and then store them.

There is a correct way to pick apples. Never pull the fruit off or shake the branch. Lift the apple upward in the palm of your hand rather than your fingers, which can bruise the fruit, and then twist lightly to pick it. If it’s ready, it will come off easily in your hand. Apples with the stems on them last longer. Remember to place them gently in your basket or bag to avoid bruising them. It is true that “one bad apple can spoil the whole bunch.”

JoAnne Skelly is associate professor & extension educator emerita at University of Nevada Cooperative Extension. Reach her at skellyj@unr.edu.