Peaches

Peaches ripen on the counter and should stay there until they are ready — 3–5 days depending on how firm they were. Refrigerating an unripe peach ruins it.

Once ripe — fragrant, and yielding to gentle pressure at the shoulder rather than the tip — move them to the refrigerator, where they hold for about 5 days.

To speed ripening, put them in a paper bag, optionally with a banana or apple. To slow it, spread them out in a single layer, stem-side down, out of the sun.

Do not stack peaches or leave them in the bag from the store. They bruise readily and a bruise becomes a rot site within a day.

Peaches freeze well as slices for 8–12 months, treated with lemon juice or a light syrup to prevent browning.

Peaches are climacteric, ripening after harvest in response to ethylene, and they are picked firm for shipping. That is why a supermarket peach in July is often hard and flavorless — it has not finished ripening, and it needs counter time.

But there is an important caveat: peaches develop sweetness only on the tree. After harvest they will soften, become juicier, and grow more aromatic, but the sugar content is fixed at picking. A peach picked too early can never become a good peach, however long you wait. Softening is not the same as ripening.

Refrigerating an unripe peach causes chilling injury — sometimes called internal breakdown or mealiness. Cell membranes are damaged and the enzymes that soften the flesh properly are disrupted, so the peach turns dry, woolly, and grainy instead of juicy, and often browns internally. This is irreversible and is the most common way a good peach is spoiled at home.

The typical rot is brown rot (Monilinia), which appears as an expanding tan-brown lesion, often with fuzzy spore masses. It moves fast, and infected fruit spreads to neighbors.

Wrinkled skin is water loss. Discard fruit that is leaking, moldy, or smells fermented.