Preserving Mushrooms and Mushroom Salt

Given my previous post about how little I generally find while foraging with the family, it would seem contradictory to now write about storing a large haul. However, knowing the growing habits of those winter chanterelles, I couldn't resist returning solo for a couple of hours.
After doing this a couple of weekends on the trot I ended up with 3-4kg of winter chanterelles (craterellus tubaeformis) and close to another 1kg of hedgehog mushrooms (hydnum repandum). There was considerably more than this out there, but I went each time with a friend who took his share, and with a time limit I couldn't stay picking all day.

Much as a binge on mushrooms would have been great, being able to reach for a few wild mushrooms over the leaner foraging months has too much appeal, so I've preserved them in a variety of ways. 

Freezing

The method really depends on the age and condition of the mushroom. Young small mushrooms can be frozen whole, then defrosted and used in any recipe as a fresh mushroom.
If the mushrooms are older or not in perfect nick, then sauté them before you freeze. Keep small ones whole and chop up any larger ones. Heat up a mix of butter and oil over a medium heat, add the mushrooms and increase the heat until most of the liquid has evaporated and the mushrooms are cooked. Cool, then freeze. It is worth mentioning that you shouldn't adorn these mushrooms with garlic/seasonings etc as this can produce some bitter off flavours; that can be done once they are defrosted. 

Freezing should not be considered a long term storage solution; try to use the mushrooms within 2-3 months. 

Drying

This is possibly the most widely practised mushroom preserving technique. Not only will it allow them to be kept indefinitely, but the flavour of most mushrooms will intensify once rehydrated. I say indefinitely, but really they'll keep around a year, bringing us nicely back to the next season. Certain mushrooms such as the Cep (boletus edulis) are dried almost as standard.
This can be done by threading a small amount of mushrooms onto a string and hanging in a warm spot with airflow until dry, or can be done using a dehydrator if you have one. Personally I use the oven method as I generally have more than the string method would allow and no dehydrator. When using any method the aim is to fully dry the mushrooms before they spoil but without cooking them

Start off by cutting the mushrooms into 3-4mm slices and laying on a baking tray. Some people recommend using a rack for airflow all around the mushrooms, some baking paper to stop them sticking. Me, I just stick them straight onto the tray and haven't had any issues. Put the tray in the oven, a temperature of around 50c will be ideal for the process and leave the door of the oven open which will create airflow and allow the moisture to escape.

It will probably take 6-8 hours for the mushrooms to dry, but it could be a lot more depending on the size of the slices and the moisture content to begin with.

To use the mushrooms, soak in warm water for approx 15 minutes, or add them directly to a dish which will simmer for a decent length of time. If soaking them first the soaking water can also be added as this has a decent mushroom flavour.

Pickling/Salting

I'd only ever dried or frozen mushrooms so this was a bit of an experiment. There was a method of pickling which involved boiling in white whine vinegar with salt, peppercorns and a couple of spices before placing into sterilised jars and covering with olive oil, but I decided against this as I wanted to retain as much of the mushroom flavour as possible.
Salting is an  Eastern European method of preserving mushrooms and can be done either wet (brining) or dry. To salt them you take a large pot and add a layer of course salt, followed by a layer of mushrooms and repeat. Brining seems to involve boiling the mushrooms in salty water and then covering with a vinegar brine.

I ended up using a method which sits somewhere between the two above.

The mushrooms were laid in a dish, covered with salt and left for a couple of hours. After this time I drained the liquid which had formed, covered with more salt and left for another couple of hours.

 I then put the mushrooms in a sieve, leaving as much of the salt in the dish as I could (more on that in a moment) and quickly rinsed them off.
I then put them into simmering cider vinegar for a couple of minutes, switched off the heat and left for 4 hours. After this time they were drained, added to a sterilised kilner jar and covered with olive oil.
 These were absolutely delicious with cold meat and cheese platters over christmas and received a big thumbs up from anyone who tried them.

Mushroom Salt

The salt I saved earlier was for an experiment. I figured that if it has been hydrated in the juices from the mushrooms, once dried out again there may be a little extra flavour in the salt. So I spread it out on an oven tray and dried it in the same way as the mushrooms. It worked! Once dry there was a taste of mushrooms to the salt. Not strong, but rather nice. I will definitely try to save more of the salt next time and make this a regular part of preserving.

Soup

The last of the mushrooms were turned into soup and the soup frozen. There are hundreds of mushroom soup recipes on t'interweb and I'm sure there will be one for everyones tastes.
I gently cooked diced potato, onion, leek and garlic in butter for 10 minutes, added mushrooms and thyme and cooked for another 10 minutes. Seasoned, simmered in veg stock for 10 minutes and then blended worked for me. When I defrost some, I'll probably add a dash of cream but it isn't necessary.

There are still a few species of edible mushroom out there, in fact some of the experts/old hands I follow in various places are still finding baskets full of Winter Chanterelles, Hedgehogs, Velvet Shanks and Oyster mushrooms, so it's not too late to get out and have a search yourself. I know if it ever stops raining in Dorset I'll be back out there.