Arrowroot starch, also called arrowroot flour, arrowroot powder, or simply arrowroot, is an edible starch from the rhizomes (rootstock) of the West Indian arrowroot plant.
Arrowroot tubers contain about 23% starch. They are washed, cleaned of the paper-like scale, washed again, drained, and finally reduced to a pulp by beating them in mortars or subjecting them to the action of the wheel-rasp. The milky liquid thus obtained is passed through a coarse cloth or hair sieve, and the insoluble pure starch settles at the bottom. The wet starch is dried in the sun or in a drying house. The result is a powder that is then packed for market in air-tight cans, packages, or cases.
Pure arrowroot, like other pure starches, is a light, white powder that feels firm to the finger and crackles like newly fallen snow when rubbed or pressed. It is odorless when dry, but it emits a faint odor when mixed with boiling water. When mixed with water and cooked, it swells into a jelly. Arrowroot starch has in the past been quite extensively adulterated with potato starch and other similar substances, so care is needed in selection and buying. Cooked pure arrowroot is very smooth in consistency, unlike adulterated arrowroot mixed with potato and other starches containing larger particles.
Arrowroot thickens at a lower temperature than does flour or cornstarch. It is recommended to mix arrowroot with a cool liquid before adding to a hot fluid. The mixture should be heated only until the mixture thickens and removed immediately to prevent the mixture from thinning again, since overheating tends to reduce arrowroot's thickening ability.
Arrowroot can be incorporated into biscuits, puddings, jellies, cakes, hot sauces, beef tea, milk or veal broth, or noodles. When boiled with a little flavoring added, arrowroot make an easily digestible food for children and people with dietary restrictions. It makes clear, shimmering fruit gels and prevents ice crystals from forming in homemade ice cream. It can also be used as a thickener for acidic foods, such as oriental sweet and sour sauce.
The lack of gluten in arrowroot flour makes it useful as a replacement for some of the wheat flour in many recipes. Like other pure starches, however, arrowroot is almost devoid of protein and does not equal wheat flour functionally or nutritionally.
If you eat a large quantity of arrowroot it may cause stomach pains and very bad gut illnesses.