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The Jerusalem artichoke is a tuber with an apple-like flavor and is not related to the globe artichoke (Cynara scolymus). It is grown for its edible tubers and foliage. The leaves are lanceolate with upper leaves clasping the stem, 10 to 30 cm long and 2 to 5 cm broad, coarsely toothed or lobed, and deeply ribbed: they resemble wild chicory (Cichorium intybus).
Within the tubers of Jerusalem artichoke, storage carbohydrates are in the form of both starchy amylopectin and high molecular weight non-starch polysaccharides (NSP). The composition of NSP, soluble glucans (oligosaccharides with beta 1–4 linkages), and fructose oligosaccharides (mainly inulin) comprise about 4% of the weight of dry tuber. The carbohydrate composition varies depending on whether it is derived from sun or shade-grown tubers.
NSP is particularly resistant to human digestion and recent research has demonstrated potential prebiotic activity. The tuber is a good source of beta-carotene and phosphorus. The Jerusalem artichoke also contains the flavonol silymarin, which may have antioxidant activity in humans, and other polyphenols such as quercetin and rutin. In addition to carbohydrate content, Jerusalem artichoke tubers are a source of dietary fiber.
Jerusalem artichoke is especially high in fructooligosaccharides (FOS), making it a prebiotic, which increases the number of Bifidobacteria and Lactobacilli bacteria. Since these two types of bacteria help to boost the immune system, Jerusalem artichoke has potential health benefits for people with autoimmune diseases such as rheumatoid arthritis and multiple sclerosis. Jerusalem artichokes are also rich in potassium, magnesium, iron and phosphorus. Jerusalem artichokes can be included as part of a healthy diet for disease prevention.
Jerusalem artichoke is known for its tuber which can be eaten cooked or raw, but it is also used in livestock feedstock due to its high starch content. Here we describe some of the key issues that are debated in literature regarding Jerusalem artichoke's nutritional value and health benefits.
The edible tubers contain a carbohydrate-rich storage polysaccharide inulin. Inulin is a soluble fiber which can be considered prebiotic, promoting the growth of beneficial gut bacteria and improving overall digestion.