Dried OnionDrying Time, Storage and Using Its Sweetness

Onions are a staple of savory flavor in almost every kind of cooking.

Drying takes away their sharpness and makes them sweeter and crunchier. Use them in soups, stews and stir-fries to make the most of their flavor.

Onions are high in sugar and water, so they don’t get crisp when dried. They mold easily partway through drying, so stop after 3–4 days and store them in the fridge.

	Drying time	Storage
Dry	3–4 days	2 weeks in the fridge
Semi-dried	Half a day	3 days in the fridge

Drying times assume drying during the day in sunny weather and bringing them in at night.

How to dry onion

1. Cut: Peel, trim the root end, and cut lengthwise into 8 wedges.
2. Separate: Separate each wedge into individual layers before drying, so nothing overlaps and they dry faster.
3. Lay out and dry: Spread on a basket without overlapping, somewhere sunny and breezy. Toss about once a day and bring in by evening.
4. Stop after 3–4 days: The longer they dry, the more likely they are to mold. After 3–4 days, stop and put them in the fridge.

Where and when to dry is covered in How to Dry Vegetables, and tools in Tools for Drying Vegetables.

When it’s done

Dry (3–4 days)

It’s done when the pieces have shrunk thin and the edges look translucent and slightly amber. It stays a little soft, but no moisture should seep out when pressed.

Semi-dried (half a day)

The surface is dry and the pieces are limp. They release their sweetness quickly when fried, saving time on curry or onion soup.

Day by day

Before drying

Day 1

Day 2

Day 3

Day 4

Storage

• Dry: Keep in a bag in the fridge and use within about 2 weeks.
• Semi-dried: Keep in a bag in the fridge and use within about 3 days.
• Frozen: Both can be frozen for 1–2 months. Use straight from frozen in stir-fries and soups.

Fuzzy white or green growth, black spots or a bad smell are signs of mold or spoilage. Don’t eat it; throw it away. More in How to Store Dried Vegetables.

How to use it

• Use it dry: Add straight to soups, miso soup, curry, stew and stir-fries. Simmering brings out its sweetness.
• If it’s still sharp: Blanch for about 30 seconds to soften any remaining bite.
• Good in: Onion soup, curry, hashed beef, nikujaga (Japanese meat and potato stew), kakiage.