Blueberries

Blueberries keep 1–2 weeks refrigerated — considerably longer than other berries — and as always should not be washed until you eat them.

Store them in a ventilated container in the fridge, in a shallow layer, with a paper towel to catch condensation. The clamshell they came in works well.

Handle them gently to preserve the bloom, the dusty gray-white coating on the skin. That is the fruit's own protective wax, not residue, and rubbing it off shortens their life.

Sort out any soft or moldy berries when you get home.

Blueberries are the best of the berries for freezing, keeping 8–12 months with very little texture loss. Freeze them unwashed and loose on a tray, then bag them — washing before freezing makes them stick together and turns the skins tough.

Blueberries outlast strawberries and raspberries by a wide margin, and the reason is visible on the fruit: the bloom.

That powdery pale coating is epicuticular wax the plant produces, and it is a genuine barrier. It limits water loss and it physically impedes mold spores from reaching the skin. Combined with a tough, continuous skin — unlike a strawberry's exposed flesh or a raspberry's fragile aggregate structure — it gives blueberries the best natural packaging of any common berry.

They are also fairly acidic and dense, which further discourages microbial growth.

The failure mode is still Botrytis gray mold, just slower, along with softening as the fruit loses turgor. Berries that have gone soft, wrinkled, or leaky should be removed; those touching a moldy one should go with it.

Red or purple-tinged berries in a punnet are underripe rather than spoiled. A very dark, dull appearance with a wrinkled skin is over-ripeness.

Discard moldy berries entirely. As with all high-moisture soft fruit, the visible colony is only part of what is present.