Gather only mushrooms that you can, with certainty, identify as edible mushrooms
There are thousands of mushroom species in Finland. Of these, more than two hundred are edible. For most of the mushroom species, we have no information as far as their edibility is concerned. Mushroom toxicity is always specific to the species. For this reason, it is important to pick up only species that can be identified, with certainty, as edible! Deadly toxic mushrooms include at least the European destroying angel (Amanita virosa), the death cap (Amanita phalloides), the deadly webcap (Cortinarius rubellus) and false morels (Gyromitra esculenta). Correct handling of false morels nevertheless can remove toxic compounds.
Once collected, mushrooms should be cleaned and processed fast, preferably during the same day. If not processed immediately, they should be kept stored in an airy container in fridge temperature (+2 – +6°C). Washing of hands before and after handling mushrooms is recommended. Mushrooms need dedicated chopping boards and knives; alternatively, the implements used in their handling must be carefully washed before using them on other foods.
In addition, certain forest mushrooms must be processed in a correct way to prevent possible harmful effects. Certain milkcaps, especially, contain bitter compounds, which may cause nausea. For this reason, certain mushroom species must be cooked before consuming them. Recommended cooking (by parboiling) times for the following common forest mushrooms are:
- northern milkcap 5 mins.
- rufous milkcap 10 mins.
- woolly milkcap 10 mins.
- honey fungus 10 mins.
Parboiled mushrooms must be cooled quickly before freezing them if they are not immediately prepared for food. Frozen mushrooms are preserved in good condition for at least several months. Mushrooms thawed from their frozen state must be used as soon as possible because otherwise they will go bad soon after thawing. Dried mushrooms must be stored well protected because they go bad quickly if affected by moisture.
To avoid harmful substances in the environment, do not pick edible mushrooms from the vicinity of polluting industrial plants, urban centres or alongside roads with heavy traffic. According to the recommendations of the European Commission (2003/274Euratom), the limit for Cesium 137 content in foods to be sold is 600 becquerels per kilogram (Bq/kg). Trade with wild mushrooms in the area of the EU must also comply with this limiting value. In Finland, some mushroom species occurring in the worst areas of fallout from the Chernobyl nuclear plant accident (1986) may breach that limit.