This annulated tuber looks a bit like a puffy caterpillar. It is called "knotroot" because it resembles a succession of knots, but there is also another variety that looks more like a shell. Its refined, slightly sweet flavour is reminiscent of salsify or artichoke, hence its other names: Chinese or Japanese artichoke. The French writer Simone de Beauvoir called it a "sad vegetable"… but writers aren't necessary gastronomes!
Some say it originated in China, while others claim it came from Japan. Whatever the case, it was introduced into France in 1882 by Messieurs Bois and Pailleux, who grew it in their garden in Crosnes. They began selling it throughout France. In 1887 stachys affinis was given the French name "crosne," after the village in which it had been cultivated. Though it became widely known in France, it was gradually forgotten over the years. It is beginning to reappear, in "ready to cook" format, which saves the cook from the tedious job of cleaning it. It can be found for sale between November and March and in certain regions of France it has even been adopted as a Christmas food.
The Chinese call it "kam lu," (sweet pink) or "tsao che tsan" (silkworm stone plant).
The plant itself is a nettle-like herb of the Lamiaceae (mint) family. It puts out a stem approximately 30 cm (12") high that bears deciduous, somewhat tousled leaves and white flowers. The edible parts are the tubers that grow underground and which can be harvested beginning in November once the foliage has dried up completely.
Choose plump light-coloured tubers, preferably pearly white and smooth. Fresh knotroot is whitish, but when stored in too dry an environment it will soften and turn a beigish colour.
- Never peel.
- Place in a towel with coarse salt and rub,
- then remove the last layer of skin under running water.
- Place into cold acidulated water to preserve the colour.
- Boil and serve simply with butter and parsley or cream.
- Cook covered in a small amount of butter or liquid.
- Sauté with small pieces of bacon and chives or onions.
- Blanch for two minutes in salted water; drain and dry; serve in salads, accompanied by eggs, smoked uncooked ham and chopped parsley.
- Blanch for two minutes in salted water; dry; sauté in a wok Japanese-style with marinated plums, beef, mushrooms and cubes of tofu.
- Can be substituted for water chestnuts in some Asian dishes.
Nutritional values per 100 g
This is a low calorie vegetable with 75 calories, 2.6 g protein, 16 g carbohydrates and no fats. Rich in nutrients, it contains starch, sugar and minerals, making it an excellent source of energy. If you're on a diet and looking for something different, try it!