Chestnuts, chestnuts!

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Not being a native English speaker, I was a little puzzled when, as a teenager, I read that expression in J.R.R. Tolkien's "The Hobbit", specifically in the most memorable (and my favorite) chapter "Riddles in the Dark". Gollum used it to indicate that Bilbo's riddle was an old one. In English, an "old chestnut" is a joke that has been often repeated, to the point of being not funny anymore.  Apparently, the use of this expression dates back to the early 19th century, and it's not really related to the chestnut trees and their nuts, which are really the topic of this post :)

To me both the sweet, edible chestnut and the horse chestnut —which is neither sweet nor edible: in fact, it's toxic— are a symbol of autumn, and I love to gather and use both. I didn't want to let autumn pass (although temperatures here are already in the winter realm, the trees are still showing the wonderful yellow and red colors of the fall) without dedicating a post to these trees. Even if they are both called "chestnut", they aren't really related. Their leaves look a bit similar, but upon closer inspection there are differences in the position of the leaves, and also in the flowers and fruits, as highlighted in this beautiful video and in this side-by-side comparison. In fact, the nuts look so different that, once you've learned which one is which, there's little chance that you'll ever mistake them.

Let's start with the sweet chestnut (Castanea sativa), a tree native to southern Europe and parts of Asia. The nuts are wrapped in spiky pods that look a bit like little green hedgehogs and are very painful to touch: I highly recommend to wear gloves (if possible, thick leather ones) when picking and opening them.

The nuts are delicious. They are a classic of European Christmas markets, and of pedestrian streets in autumn and winter. Although the chestnuts sold in the market are much bigger (and require no cooking or preparation whatsoever), I still love to pick my own from the woods around our house. It has become a ritual of October for me and my husband to go to the forest with our dog to search for chestnuts (the dog only accompanies us; he is in no way trained to find and/or pick chestnuts!). And we're not the only ones: we meet a lot of people doing the same, especially on weekends. 

Chestnuts, just picked from the forest.

Preparing the chestnuts can be a bit laborious; but it's still a task that I enjoy. Before roasting or boiling  them, one must cut the hard shell with a sharp knife, otherwise they might explode (as this video attests). Most people cut an X shape on the pointed side of each nut. In previous years I roasted the chestnuts in the oven for 20-40 minutes; however, they have an inner, softer skin which also needs to be removed (as it tastes quite bitter), and it wasn't easy for me to do this after baking them. This year, I tried a new method: first I cut and removed the hard shell, and then proceeded to boil the chestnuts for a short time (about 10 minutes). It's easier to peel the inner skin while the nuts are still hot, so you might sacrifice your fingers a bit during this operation. For me it isn't so bad, as I have realized that my hands are not that sensitive, so I can peel them without problems.

Once cooked, the chestnuts taste delicious eaten as nuts, in pumpkin soup, or in salads. This year, I also made a great focaccia bread with chestnuts and some meaty mushrooms called "Kräuterseitlingen". All amazing. 

As for the toxic cousin, the horse chestnut (Aesculus hippocastanum L.) has a fruit that is larger in size and rather ball-shaped, not pointy as the edible chestnut. The pods are also smooth and have fewer (and less painful) spikes, and the leaves are all attached to the same point of the stem (so that a leave looks like a 5- or 6-fingered hand). 

Although horse chestnuts are poisonous and should never be eaten, their extracts are widely used in herbal medicine. In pharmacies there are standardized extracts that can be taken internally; but home preparations should only be used externally. Horse chestnuts are often an ingredient of creams and gels used to treat problems such as varicose veins and chronic venous insufficiency in the legs. Their main constituent, aescin, is a mixture of saponins that has been found to strengthen the veins and reduce swelling.

Every autumn I pick horse chestnuts and use them to prepare an alcohol-based tincture. For this, I cut them, put them in a jar, fill it with vodka, and let it stand for a few weeks, after which the liquid will have taken a dark brown color. The tincture has a soapy feel (due to the saponin content), and although it can be applied directly to the skin, I prefer to use it to prepare a cream (with almond oil) or a gel (using a thickening agent called Xanthan gum). There are, of course, creams and gels ready to use, but I like to make my own experiments!

Horse chestnut tincture in process (left) and ready (right).