“I threw out more chestnuts than I roasted”, the old storage method that starts with a bowl of water and keeps them fresh for weeks
A bag of chestnuts can look perfectly good until you start scoring them for the oven. One feels hollow. Another has a tiny hole you missed at the store. By the time you’ve sorted out the ones worth roasting, there’s barely enough left to cover the tray.
That’s why an old Italian storage method starts with a bowl of water. Some of the chestnuts give themselves away as soon as they hit the surface. The rest stay in the bowl for days. That second part is what turns a quick sorting trick into a method for keeping fresh chestnuts.
How long to leave the chestnuts in water
Start with fresh, unpeeled chestnuts. Set aside any with split shells, visible mold, soft spots, or small round holes. Put the rest in a clean bowl and add enough drinking water to cover them completely. Use unheated water and keep the bowl in a cool spot out of direct sunlight.
Leave them submerged for five to seven days. That’s the traditional schedule for Italy’s Combai chestnuts, and it includes one full change of water halfway through. If you’re doing the seven-day soak, drain the bowl around day three or four and refill it with clean water. Check the water level each day and top it up if the shells start poking through.
In Italy, this soak is called curatura. Fresh chestnuts contain far more water than most nuts, which is one reason they don’t keep like a bag of walnuts. The long soak is a traditional way to prepare them for storage and help limit decay. The FAO describes how growers sort, soak, and dry chestnuts before storing them.
What to do with the chestnuts that float
Scoop out and discard the chestnuts that float when you fill the bowl. Do the same if any rise to the surface later in the soak. A floating chestnut may be empty, dried out, or damaged by insects. Take a look at the sinkers when you drain them, too. A chestnut can sink and still have a hole or a soft patch.
Dry the shells before you put the chestnuts away
At the end of the soak, tip the chestnuts into a colander and let the water run off. Spread them in a single layer on a clean wire rack, with a little space between them. A tray lined with a clean, dry towel works too. Turn the chestnuts as they dry so the side resting on the towel gets some air.
Start checking after a few hours. Feel the flat underside and look around the pointed tip, where drops can linger. The shells should be dry all over before you bag them. You’re drying the outside so the chestnuts don’t go into storage wet.
Where to store them once they’re dry
Leave the shells on and put the chestnuts in a perforated produce bag in the refrigerator’s crisper drawer. If you only have a plain produce bag, poke a few small holes in it before filling it so moisture can escape.
Plan to roast or cook the chestnuts within a few weeks. If you’re taking out a handful at a time, check the rest of the bag while it’s open and discard any that have softened, grown mold, or developed a sour smell. The bowl does the first round of sorting, but this last look is what keeps a bad chestnut off the roasting tray.