Prevent Berry Mold: Wash With Hot Water.
Strawberry lovers used to have to wait until summer for their berry fix, but these days you can get good berries almost year round. Nothing makes a good berry go bad faster than mold. But with a simple change to your berry-washing routine, you can keep your strawberries (and other berries) mold free much longer.
Mold, like all living things, likes to make more mold. It does so by spreading tiny airborne spores that are pretty much everywhere (just ask your average allergy sufferer). Mold loves the moist, humid surfaces of berries because their thin skins provide both a steady flow of moisture and break easily.
Cold temperatures slow mold growth – which is why berries left on your counter get moldy faster than those in your fridge. But heat is actually your best defense against berry mold according to New York Times food writer Harold McGee.
Here’s the trick: When you first get your berries home, instead of rinsing them in cool water, give them a quick soak in hot. About 30 seconds in hot (not boiling) water should do it for strawberries. Blueberries might need a little longer (or hotter). The best temperature varies by berry but is between 120° and 140° F (strawberries are 125° F).
If your water heater is set to the default 140° F, you don’t even need to heat the water. But be careful! Water can burn skin at 130° F.
And don’t forget to dry your berries before you refrigerate them – lay them on a paper towel or dry them gently by hand. Any extra moisture on their surface will encourage mold growth.