Vegetables

How to make Fermented Mushrooms

Button mushrooms blanched then fermented in a garlicky brine until savoury, tangy, and firm. Expect about 25 minutes of active prep, then 7-14 days of fermentation, with a taste check to decide when to refrigerate.

Quick answer

Prepare the mushrooms, mix the brine, and pack everything into a clean jar with the mushrooms fully submerged. After 3 days, make sure the mushrooms stay submerged and look for the first signs of fermentation. After 7 days, taste the mushrooms and decide whether to refrigerate now or let them keep fermenting. After 14 days, do a final taste check, then refrigerate the mushrooms in their brine.

Difficulty
Beginner
Total time
14 days
Ingredients
5
Steps
4

Safety

  • • Keep the mushrooms fully submerged below the brine throughout fermentation.
  • • Use non-iodized salt and non-chlorinated water for a more reliable ferment.
  • • A clean sour smell is normal. A rotten smell, slimy brine, or fuzzy mold means the batch should be discarded.

Step-by-step

Day 0

Step 1: Prepare and pack

Prepare the mushrooms, mix the brine, and pack everything into a clean jar with the mushrooms fully submerged.

  • Set up clean equipment Wash the jar, weight, bowl, and any utensils before you start.
  • Clean mushrooms Wipe the mushrooms clean and halve any large ones.
  • Blanch mushrooms Blanch the mushrooms briefly, then drain and cool them.
  • Mix brine Dissolve the salt fully in the water before pouring it over the mushrooms.
  • Pack jar Pack the mushrooms with the aromatics, pour in the brine, and keep everything below the surface.
Day 3

Step 2: Check fermentation

Make sure the mushrooms stay submerged and look for the first signs of fermentation.

  • Check submersion Press any floating mushrooms back below the brine if anything has shifted upward.
  • Check activity Look for a few bubbles, slightly cloudy brine, or a fresh sour smell.
  • Check aroma The jar should smell fresh and earthy and savoury rather than rotten.
Day 7

Step 3: Taste and decide

Taste the mushrooms and decide whether to refrigerate now or let them keep fermenting.

  • Taste Lift out a piece with a clean fork and judge the balance of salt and tang.
  • Resubmerge and cover Return the mushrooms below the brine before continuing the ferment.
Day 14

Step 4: Finish and store

Do a final taste check, then refrigerate the mushrooms in their brine.

  • Taste final batch Confirm the mushrooms are as tangy as you want before ending room-temperature fermentation.
  • Refrigerate Seal the jar and refrigerate the mushrooms in their brine to slow the fermentation.

What to look for

  • • Day 0: The mushrooms are fully covered by brine and held down with a weight. That gives the batch the best chance to ferment cleanly and stay mold-free.
  • • Day 3-4: The brine looks slightly cloudy and you may see a few small bubbles. Those are normal early signs that fermentation has started.
  • • Day 7 and beyond: A piece tastes savoury, tangy, and firm. Use taste to decide whether to refrigerate now or ferment a few more days for more tang.

Troubleshooting

  • The brine does not cover the mushrooms. Some liquid was lost or the pack was loose. Top up with a 3 percent salt solution until everything is covered again.
  • No bubbles appear after a few days. The room is cool or fermentation is starting slowly. Give it another day or two and rely on smell and taste as well as visible bubbles.
  • A piece floats above the brine. The weight shifted or the jar was packed loosely. Push it back down, adjust the weight, and make sure all solids stay submerged.
  • It tastes too salty early on. The ferment is still young or the brine ran slightly strong. Let it ferment a little longer before judging, then serve with unsalted foods if needed.
  • The mushrooms turn slimy. They were not blanched, were left exposed to air, or fermented too warm. Discard the batch and start again with blanched mushrooms kept fully submerged in a cooler spot.

Storage

Seal the jar and refrigerate once it tastes balanced to you, keeping the mushrooms below the brine. It will continue to mature slowly in the cold.

Shelf life: about 1 month refrigerated

Serving suggestions

  • • Add to antipasto and charcuterie boards.
  • • Stir into grain bowls and salads.
  • • Serve alongside grilled meats.

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Frequently asked questions

What is Fermented Mushrooms?

Button mushrooms blanched then fermented in a garlicky brine until savoury, tangy, and firm. Expect about 25 minutes of active prep, then 7-14 days of fermentation, with a taste check to decide when to refrigerate.

How long does it take to make Fermented Mushrooms?

Most batches of Fermented Mushrooms are ready in about 14 days, though exact timing depends on temperature and how the ferment tastes along the way.

Is Fermented Mushrooms hard to make?

Fermented Mushrooms is a great beginner project — no special skills required, just clean equipment and a little patience.

What do you need to make Fermented Mushrooms?

You'll need Button mushrooms, Filtered water, Sea salt, Garlic, Fresh thyme.

How do I know when Fermented Mushrooms is ready?

Watch for these cues: Day 0: The mushrooms are fully covered by brine and held down with a weight.; Day 3-4: The brine looks slightly cloudy and you may see a few small bubbles.; Day 7 and beyond: A piece tastes savoury, tangy, and firm..

How do I store Fermented Mushrooms?

Seal the jar and refrigerate once it tastes balanced to you, keeping the mushrooms below the brine. It will continue to mature slowly in the cold. Shelf life: about 1 month refrigerated.

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