Preserving mushrooms with salt is an old Russian and Karelian method.

Mushrooms preserved this way keep for a long time, even for years, and are usually used in making delicious mushroom salad.

fresh milkcaps: *)

rufous milkcaps (Lactarius rufus),
woolly milkcaps (L. torminosus) and/or
northern milkcaps (L. trivialis, L. utilis)

water (for quantity, see instructions below)
coarse sea salt (for quantity, see instructions below)

When raw, these milkcaps are inedible and have an unpleasant, bitter taste. They become edible after parboiling. Note that some northern milkcaps may turn slightly bluish during cooking, which is normal and perfectly harmless (see the picture on right).

In picture on right: pieces of northern milkcaps having obtained a bluish tint after boiling.

Scrape the milkcaps clean under running water with a knife. Detach the stems from the caps and discard them. Cut the caps in 2 - 4 pieces. Weigh the mushrooms.

If you do not have a large enough saucepan, cook the mushrooms in batches. Fill a large saucepan with water: use 2½ litres of water per 500 grams of mushrooms. Bring the water to the boil and add the mushrooms. Cook for 10 minutes, no less. Pour the mushrooms in a colander and rinse thoroughly with plenty of cold, running water. Discard the water used for boiling: it must not be used for cooking. Repeat the boiling and rinsing.

Continue boiling and rinsing twice with the rest of the mushrooms. When all the mushrooms have been prepared, drain and squeeze them as dry as possible. Let them cool thoroughly and weigh them. Place the mushroom pieces, their gill-side downwards, in sterile glass jar(s) in layers with salt, starting with salt on the bottom. Use 50 to 100 grams of coarse sea salt per 500 grams of cooked mushrooms. Sprinkle the rest of the salt on top of the mushrooms.

Press the mushrooms tightly in the jar and place a weight on top: eg a tightly closed small clean plastic freezer bag filled with cold water or clean pebbles. Close the jar with sterile lid and store in refrigerator for 5 - 6 days. During this time, a salt brine will develop in the jar.

Check the mushrooms periodically to ensure that the brine entirely covers them, otherwise the mushrooms may start to dry out. If this happens, add some boiled, cooled 10 %-salt brine in the jar: use 50 grams of salt per ½ litre of water. Store the jar in a cool place, the temperature of which should be between 2 and 7 °C at the maximum.

The mushrooms will be "ready" after 4 - 6 weeks. Before eating they must be soaked in plenty of cold water for several hours in order to remove the excess salt. But be careful not to remove all of the salt, so keep tasting the mushrooms every now and then while soaking, until the taste is suitable.

In Finland, readily salted mixed forest mushrooms are sold practically in every store (see the picture above right). They just need to be soaked in water before use, as described above.

In picture on bottom right: store-bought vacuum-packed Finnish salted mushrooms (pickle milkcaps).

*) When picking your own mushrooms, if you are not sure whether a mushroom is edible or poisonous, just leave it unpicked. Better be safe than sorry. Also check that the mushrooms used in this recipe are edible in your country or region. In Finland these mushrooms are edible, provided that they are first thoroughly soaked and/or cooked in a way described in this recipe.
Read more about Finnish mushrooms here.

Recipe source: family recipe/traditional Finnish recipe.