by Daphne Lambert
JERUSALEM ARTICHOKES - Helianthus tuberosus
There are few plants less fussy than Jerusalem artichokes. The tubers grow well in tubs (the crop in the image above was grown in a tub with 1/3rd bokashi compost) or in an open situation in rich soil. The plants grow tall so can be used to make an effective wind break.
Plant tubers 4 – 6” deep about 12” apart in the spring. If growing in a tub they will need watering, however in garden soil they are very water efficient and will only need watering in cases of severe drought. The top growth dies back in late autumn, prune down to a 3” stump. Lift the tubers as and when required throughout the autumn and winter months. Any tubers left in the ground will regrow the following spring.
The Jerusalem artichoke plant bears many starchy edible rhizomes, with either a grey, purple, or pink skin with a sweet, delicate textured white flesh inside. Scrub well and boil or steam before turning into a creamy soup. Great peeled and roast before tossing into salads, they make a delicious houmus – see below for the recipe.
Health benefits of Jerusalem artichoke
Jerusalem artichokes are an excellent source of minerals and electrolytes, especially potassium, iron, and copper. 100 g of fresh root provides 9% of daily required levels of potassium. Potassium is a heart friendly electrolyte which can reduce blood pressure and heart rate by countering pressing effects of sodium.
Jerusalem artichokes contain, probably the highest amount of this trace element among the common edible roots and tubers. They also contain small amounts of anti-oxidants such as vitamin C and carotenes.
They also contain small levels of some of the valuable B-complex group of vitamins such as folates, pyridoxine, pantothenic acid, riboflavin, and thiamin. Thiamine, also known as vitamin B1, is crucial for the proper functioning of the nervous system and the muscles. It is also needed for carbohydrate metabolism as well as for the production of hydrochloric acid in the stomach. Lack of hydrochloric acid may impair protein digestion and cause stomach pain by inhibiting the activation of the enzyme pepsin. The natural level of hydrochloric acid decreases as we age, and therefore especially older people might want to eat plenty of Jerusalem artichokes and other foods that promote the production of hydrochloric acid.
Jerusalem artichokes are one of the best sources of the fructo-oligosaccharide (FOS) inulin, a type of prebiotic fibre which has many health benefits. Inulin is not digested in the small intestine and moves into the large intestine where it is fermented by the gut bacteria specifically bifidobacteria and lactobacilli. Naturally present in the large intestine, bifidobacteria fight harmful bacteria in the intestines, prevent constipation, and give the immune system a boost. The digestion is accompanied by the production of hydrogen, carbon dioxide, and other gaseous products. This leads to flatulence an undesirable side-effect of eating Jerusalem artichoke and other inulin-rich foods.
Inulin & the gut-brain axis
There is growing evidence that microbes in the gut can play a key role in regulating brain functions, particularly anxiety, depression, cognition, stress response and social behaviour. Recent research on two prebiotics, fructo and galacto-oligosaccharides led by Prof John Cryan and Prof Ted Dinan, have shown that a combination of these two prebiotics, can modulate anxiety, cognition and stress-related behaviors in healthy mice. Their findings strengthens the evidence supporting therapeutic targeting of the gut microbiota for brain-gut axis disorders, “If such robust findings could be translated to humans we may have a whole new ‘psychobiotic’ way of managing stress-related disorders such as depression and anxiety disorders” says prof. John Cryan
Artichoke houmus
350g peeled and roast Jerusalem artichoke
2 tablespoons tahini
3 cloves garlic crushed
juice and zest of 2 lemons
black pepper & salt
Blend the cooked artichokes to a smooth consistency add the remaining ingredients and blend adding water if necessary until you have a smooth cream.