Mushrooms
Dried ShiitakeSun-Drying to Boost Vitamin D, Rehydrating and Storage
Dried shiitake is one of the easiest dried foods to make at home. As the water leaves, the savory flavor and aroma intensify, and once completely dry, they keep a long time at room temperature.
Shiitake contain ergosterol, which turns into vitamin D when exposed to ultraviolet light. Most store-bought dried shiitake are machine-dried, so a big advantage of sun-drying them at home is that you can increase their vitamin D.
| Drying time | Storage | |
|---|---|---|
| Dry | 2 days–1 week | 3 months at room temperature |
| Semi-dried | Half a day–1 day | 5 days in the fridge |
Drying times assume drying during the day in sunny weather and bringing them in at night. They vary a lot with size and weather.
How to dry shiitake
- Choose: Pick ones whose caps aren’t too open, with pale gills. Thicker caps have more flavor but take longer to dry.
- Clean: Don’t wash them; wipe off any dirt with a paper towel. Soaked mushrooms are slow to dry.
- Trim the base: Cut off only the hard tip of the stem. The stems are full of flavor, so leave them on and dry them too.
- Lay out: Lay them on a basket gills up, without overlapping. The compound that becomes vitamin D is concentrated in the gills, so getting sun on them is the key.
- Dry: Put them somewhere sunny and breezy, and bring them indoors by evening.
- To slice them: Cut about 5 mm (¼ in) thick, and they’ll dry in 1–2 sunny days. Handy to add straight to mixed rice and stir-fries.
Where and when to dry is covered in How to Dry Vegetables, and tools in Tools for Drying Vegetables.
When they’re done
Dry (2 days–1 week)
They’re done when the caps have shrunk and hardened and snap when bent. The center of the cap dries last. Even if the edges and stems are dry, press the center of the cap; if it still feels moist and springy, keep drying.
Semi-dried (half a day–1 day)
Only the surface is dry. Even half a day of drying boosts the flavor and aroma, so they’re great grilled or stir-fried the same day.
Day by day
Before drying
Day 1
Day 2
Drying jumbo shiitake
In Hokkaido, where mushrooms grow well, supermarkets sell jumbo shiitake with huge caps. The two in the photo cost about 250 yen. The basket is 36 cm (14 in) across, so you can see how big they are.
They’re big enough to cook as a steak and full of flavor, so we treated ourselves and dried them too. Whole, they’d take a long time to dry, so we sliced them.
Dry
Semi-dried
Day by day
Before drying
Day 1
Day 2
Storage
- Dry: Put completely dry shiitake in a bag or airtight container with a desiccant, and keep somewhere cool and out of direct sun. About 3 months. In humid summer weather, the fridge is safer.
- Semi-dried: Keep in a bag in the fridge and use within about 5 days.
- Frozen: Both dry and semi-dried can be frozen. Add them straight from frozen to simmered dishes and soups.
If they soften from moisture during storage, put them in the sun again to dry. Fuzzy white or green growth, black spots or a bad smell are signs of mold or spoilage; throw them away.
Dried shiitake keep well, so they’re good for an emergency food stock too. More in How to Store Dried Vegetables.
Rehydrating and using them
- For the most flavor, soak slowly in cold water: Rinse quickly, cover with cold water, and rehydrate in the fridge: 5–8 hours (overnight) for whole caps, 30 minutes to an hour for slices. Slow soaking at a low temperature gives a better aroma and a cleaner taste.
- In a hurry: Soak slices in lukewarm water for 10–15 minutes. Faster, but the flavor is a little weaker.
- Use the soaking water: It’s full of flavor, so use it as the liquid in simmered dishes, soups and mixed rice. Keep it in the fridge and use it by the next day.
- Put them in the sun again before using: Whether fresh or dried, putting shiitake in the sun before cooking increases their vitamin D.
Recipe
Mixed rice with dried shiitake
- About 10 slices dried shiitake
- 180 ml (¾ cup) Japanese short-grain rice
- 200 ml (about ⅘ cup) water
- A: 1 tbsp soy sauce, 2 tbsp sake
- Rinse the dried shiitake quickly and soak in the measured 200 ml of water for about 10 minutes. Keep the soaking water.
- Wash the rice and drain in a colander.
- Pour A over the rehydrated shiitake and mix.
- Put the rice and step 3 into a rice cooker, add the soaking water from step 1, and cook.
Mixing in dried green shiso after cooking is great too. The same recipe works with dried king oyster mushrooms or dried shimeji.
