The Jerusalem artichoke (Helianthus tuberosus), also called sunroot, sunchoke, earth apple or topinambour, is a species of sunflower native to eastern North America, and found from eastern Canada and Maine west to North Dakota, and south to northern Florida and Texas. It is also cultivated widely across the temperate zone for its tuber, which is used as a root vegetable.
It is a herbaceous perennial plant growing to 1.5–3 metres (4 ft 10 in–9 ft 10 in) tall with opposite leaves on the lower part of the stem. The leaves have a rough, hairy texture and the larger leaves on the lower stem are broad ovoid-acute and can be up to 30 centimetres (12 in) long, and the higher leaves smaller and narrower.
The tubers are elongated and uneven, typically 7.5–10 centimetres (3.0–3.9 in) long and 3–5 centimetres (1.2–2.0 in) thick, and vaguely resembling ginger root, with a crisp texture when raw. They vary in color from pale brown to white, red or purple.
Despite its name, the Jerusalem artichoke has no relation to Jerusalem, and it is not a type of artichoke, though both are members of the daisy family. The origin of the name is uncertain. Italian settlers in the USA called the plant girasole, the Italian word for sunflower, because of its resemblance to the garden sunflower (note: both the sunflower and the sunchoke are part of the same genus: Helianthus). Over time, the name girasole may have been changed to Jerusalem. To avoid confusion, some people have recently started to refer to it as sunchoke or sunroot.
The artichoke part of the Jerusalem artichoke's name comes from the taste of its edible tuber. Samuel de Champlain, the French explorer, sent the first samples of the plant to France, noting its taste was similar to an artichoke.
Jerusalem artichokes were first cultivated by the Native Americans long before the arrival of the Europeans; this extensive cultivation obscures the exact native range of the species. The French explorer Samuel de Champlain found domestically grown plants at Cape Cod in 1605. The Jerusalem artichoke was titled 'best soup vegetable' in the 2002 Nice Festival For The Heritage Of The French Cuisine.
Cultivation and uses
Unlike most tubers, but in common with other members of the Asteraceae (including the artichoke), the tubers store the carbohydrate inulin (not to be confused with insulin) instead of starch. For this reason, Jerusalem artichoke tubers are an important source of inulin used as a dietary fiber in food manufacturing.
Crop yields are high, typically 16–20 tonnes/ha for tubers, and 18–28 tonnes/ha green weight for foliage. Jerusalem artichoke also has potential for production of ethanol fuel, using inulin-adapted strains of yeast for fermentation.
Jerusalem artichokes are easy to cultivate, which tempts gardeners to simply leave them completely alone to grow. However, the quality of the edible tubers degrades unless the plants are dug up and replanted in fertile soil. This can be a chore, as even a small piece of tuber will grow if left in the ground, making the hardy plant a potential weed. In fact, the plant can be pernicious. It can be destructive to other plants and gardens and can overtake huge areas if left untamed. Commercial fields growing sunchoke which then change to other vegetables or crops often must be eradicated with glyphosate (sometimes twice) to stop the spread of the sunchokes. Each sunchoke root can make an additional 75 to as many as 200 tubers by fall end.
The tubers are sometimes used as a substitute for potatoes: they have a similar consistency, and in their raw form have a similar texture, but a sweeter, nuttier flavor; raw and sliced thinly, they are fit for a salad. The carbohydrates give the tubers a tendency to become soft and mushy if boiled, but they retain their texture better when steamed. The inulin cannot be broken down by the human digestive system, which can cause flatulence and, in some cases, gastric pain. Gerard's Herbal, printed in 1621, quotes the English planter John Goodyer on Jerusalem artichokes:
"which way soever they be dressed and eaten, they stir and cause a filthy loathsome stinking wind within the body, thereby causing the belly to be pained and tormented, and are a meat more fit for swine than men."
Jerusalem artichokes can be used as animal feed, and, while they must be washed before being fed to most animals, pigs forage and safely eat them directly from the ground. The stalks and leaves can be harvested and used for silage, though cutting the tops greatly reduces the harvest of the roots.
|Nutritional value per 100 g (3.5 oz)|
|Energy||73 kcal (310 kJ)|
|- Sugars||9.6 g|
|- Dietary fiber||1.6 g|
|Vitamin A equiv.||1 μg (0%)|
|Thiamine (vit. B1)||0.2 mg (17%)|
|Riboflavin (vit. B2)||0.06 mg (5%)|
|Niacin (vit. B3)||1.3 mg (9%)|
|Vitamin B6||0.077 mg (6%)|
|Folate (vit. B9)||13 μg (3%)|
|Vitamin C||4.0 mg (5%)|
|Calcium||14 mg (1%)|
|Iron||3.4 mg (26%)|
|Magnesium||17 mg (5%)|
|Phosphorus||78 mg (11%)|
|Potassium||429 mg (9%)|
|Zinc||0.12 mg (1%)|
|Percentages are relative to|
US recommendations for adults.
Source: USDA Nutrient Database
By the end of the end of the 19th Century Jerusalem artichokes were being used in Baden to make a spirit called "Jerusalem artichoke brandy," "Jerusalem artichoke", "Topi", "Erdäpfler" "Rossler" or "Borbel" .
Jerusalem artichoke brandy smells fruity and has a slightly nutty-sweet flavour. It is characterised by intense but pleasant earthy taste. The tubers are washed and dried in an oven before fermentation and distillation.
Jerusalem artichoke brandy is sometimes refined to give "red rossler". The roots of bloodroot are used. Red rossler is made by extracting the plant material extracted from the root making. It is red in colour and has a slightly bitter and astringent taste. Red rossler is considered good for the digestive system and can be used as a home remedy for cases of diahorrhea or abdominal pain. Besides bloodroot, other ingredients, such as currants, are used in the production of red rossler. The substance is as pure Tobinambur liquor with 40-45% alcohol by volume.
During fermentation and subsequent distillation of spirits, the length of the inulin molecules is of little importance, as they are not fermentable.
In the 1980s, the Jerusalem artichoke also gained some notoriety when its seeds were planted by midwestern US farmers at the prodding of an agricultural pyramid scheme. There was little market for the tuber in that part of the US at the time, but farmers were assured it would soon appear on the commodities market. The only profits were realized by the initial distributors and the first few levels of farmers (who sold their seeds to subsequent levels of the pyramid). As a result, many of the farms that had planted large quantities of the crop were ruined.
- Germplasm Resources Information Network: Helianthus tuberosus
- Purdue University Center for New Crops & Plants Products: Helianthus tuberosus
- Huxley, Anthony Julian; Mark Griffiths, and Margot Levy (1992). The New Royal Horticultural Society dictionary of gardening. London: Macmillan Publishers. ISBN 0-333-47494-5. OCLC 29360744.
- Smith, James Edward (1807). An introduction to physiological and systematical botany. p. 108f.. "A change, as I presume, of the Italian name Girasole Articiocco, sun-flower Artichoke, as the plant was first brought from Peru to Italy, and thence propagated throughout Europe."
- Flamm G, Glinsmann W, Kritchevsky D, Prosky L, Roberfroid M (2001). "Inulin and oligofructose as dietary fiber: a review of the evidence". Crit Rev Food Sci Nutr 41 (5): 353-62. doi:10.1080/20014091091841. PMID 11497328.
- "Artichoke". Collier's New Encyclopedia. 1921.
- Peter Barham. The Science of Cooking. p. 14.. "we do not possess any enzymes that are capable of breaking down larger sugars, such as raffinose etc. These 3, 4 and 5 ring sugars are made by plants especially as part of the energy storage system in seeds and beans. If we ingest these sugars we can't break them down in the intestines, rather they travel down into the colon where various bacteria digest them - and in the process produce copious amounts of carbon dioxide gas"
- Gerard's Herbal, cited in Davidson A. (1999). The Oxford Companion to Food, first edition. Oxford University Press ISBN 0-19-211579-0.
- USDA Agricultural Research Service, http://www.nal.usda.gov/fnic/foodcomp/Data//SR20/reports/sr20fg11.pdf
- C.A.R.M.E.N. e.V.: Topinambur - Energiepflanze für Biogasanlagen. In: Newsletter "nawaros" 11/2007, Straubing.
- "Jerusalem Artichoke", Commercial Vegetable Production Guides, Oregon State University
- Joseph Anthony Amato, The Great Jerusalem Artichoke Circus: The Buying and Selling of the Rural American Dream, University of Minnesota Press, 1993, ISBN 0-8166-2345-7 ISBN 978-0-8166-2345-7 (paperback), ISBN 0-8166-2344-9 ISBN 978-0-8166-2344-0 (clothbound)