What is arrowroot

Arrowroot (Maranta arundinaceae) is a tropical plant that produces an edible starchy tubers (rhizomes) widely used by indigenous peoples for medicine and cooking. The arrowroot plant is native to South America, and to the West Indies where the native Arawaks used the plant as a dietary staple and also used the arrowroot powder to draw out toxins from people wounded by poison arrows. Native Americans in both North and South America apply arrowroot as a poultice for snakebite, insect stings or bites, and skin sores. There is evidence this plant has been cultivated for at least 7,000 years. The arrowroot plant is an herbaceous perennial that dies to the ground each winter when the tubers can be dug. The plants grow about 4 foot tall in full sun to light shade, and bear small white flowers in the summer. The cylindrical underground arrowroots grow 6-8 inches long, on average, and are sharply pointed at the end (hence the name arrowroot).

At the end of the growing season there will be a cluster of these arrowroot tubers under each plant. Each individual tuber will grow a new plant for the following year so they can multiply rapidly if you dig and replant the parts that you don’t consume. In areas where the ground doesn’t freeze, just leave a few tubers in the ground after harvest. In colder climates, store the tubers in a cool dry location and replant them in the spring.

Arrowroot 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 Asian sweet and sour sauce. It is used in cooking to produce a clear, thickened sauce, such as a fruit sauce. It will not make the sauce go cloudy, like cornstarch, flour, or other starchy thickening agents would.

Arrowroot thickens at a lower temperature than flour or cornstarch, is not weakened by acidic ingredients, has a more neutral taste, and is not affected by freezing. Arrowroot does not mix well with dairy, forming a slimy mixture. It is recommended that arrowroot be mixed 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. Overheating tends to break down arrowroot’s thickening property. Two teaspoons of arrowroot can be substituted for one tablespoon of cornstarch, or one teaspoon of arrowroot for one tablespoon of wheat flour.

Allergic reactions to arrowroot has been reported like this case of generalized urticaria caused by arrowroot ingestion ¹⁾.

Figure 1. Arrowroot

Arrowroot benefits

The arrowroot tubers can be eaten boiled, roasted, baked, or fried. According to Marsono ²⁾, boiled arrowroot has a low glycemic index (GI) as little as 14. In the Victorian era arrowroot was used, boiled with a little flavoring added, as an easily digestible food for children and people with dietary restrictions. With today’s greater understanding of its limited nutritional properties, arrowroot is no longer used in this way. In some cultures they are ground and made into pastries. In Burma, arrowroot tubers, which are called artarlut, are boiled or steamed and eaten with salt and oil. Kudzu arrowroot (Pueraria lobata) is used in noodles in Korean and Vietnamese cuisine.

Test tube and animal study indicated that the diet containing arrowroot extracts increased the serum IgG, IgA and IgM levels in mice ³⁾. These results revealed that the arrowroot tuber extracts have immunostimulatory effects in vivo as well as in vitro. However further work is needed to better define the mechanisms for immunomodulation and the active substances in arrowroot extracts. Preliminary data suggests that there are two kinds of active substances in arrowroot extracts, one is kind of starch and the other one is protein, which could form some kind of prebiotic fibers that can modulate parameters in gut-associated lymphoid tissue, as well as the systemic immune system ⁴⁾.

In traditional medicine, the easily digested arrowroot starch was often used to soothe bowel irritations by dissolving in hot water or hot milk where it forms a gelatinous solution that cools to a jelly-like mass ⁵⁾. A tablespoon of arrowroot starch to a pint of liquid forms a sufficient consistency. It should first be formed into a smooth paste with a little cold water and then the hot liquid should be added while stirring briskly. A little lemon juice, or herbs and spices may be added for flavor. Arrowroot is bland, making it suitable for neutral diets, especially for people who are feeling nauseous ⁶⁾. In a small pilot study ⁷⁾ involving 11 patients, all of whom had irritable bowel syndrome (IBS) with diarrhea as a feature. The patients took 10 mL arrowroot powder three times a day for one month and discontinued the treatment for the subsequent month. Questionnaires were completed after one month on treatment and at the end of the trial after one month off treatment. The result of that small pilot study showed arrowroot reduced diarrhea and had a long-term effect on constipation. It also eased abdominal pain ⁸⁾. However, larger randomized controlled trials are needed to substantiate these preliminary results.

Arrowroot flour

Arrowroot flour can be used for gluten-free baking and is mainly used in cookies and baked goods. The lack of gluten in arrowroot flour makes it useful as a replacement for wheat flour for those with a gluten intolerance. It is, however, relatively high in carbohydrates (approximately 88.15%) and low in protein (approximately 0.3%) and does not provide a complete substitute for wheat flour in bread-making. Arrowroot can be consumed in the form of biscuits, puddings, jellies, cakes, hot sauces, and also with beef tea, milk or veal broth. Substitution with 30% arrowroot flour in the cookie bars resulted in the lighter color and the more easily crumbled texture and showed higher total dietary fibers and resistant starch content ⁹⁾. One recent study suggested that the arrowroot flour is a potential source of prebiotics and has an immunomodulatory effect ¹⁰⁾.

Arrowroot tubers contain about 23% starch. The extraction of the arrowroot starch is a somewhat laborious process: The tubers are first washed and then cleaned of the paper-like scale. The scales must be carefully removed before extracting the starch because they impart a disagreeable flavor. After removing the scale, the arrowroots are washed again, drained and finally pounded to a pulp by beating them in mortars or subjecting them to the action of a wheel rasp, rinsed in clean water, fibrous parts are removed, and the starchy water is allowed to settle. The milky liquid thus obtained is passed through a coarse cloth or hair sieve and the pure starch, which is insoluble, is allowed to settle at the bottom. The wet starch is dried in the sun. The starch yield is about 1/5 of the original weight of the tubers. The result is arrowroot starch, the “arrowroot” of commerce, that is quickly packed for market in air-tight cans, packages or cases.

Figure 2. Arrowroot flour / Arrowroot starch

Arrowroot starch

Arrowroot starch has in the past been quite extensively adulterated with potato starch and other similar substances. Pure arrowroot starch, like other pure starches, is a light, white powder (the mass feeling firm to the finger and crackling like newly fallen snow when rubbed or pressed), odorless when dry, but emitting a faint, peculiar odor when mixed with boiling water, and swelling on cooking into a perfect jelly, which can be used to make a food that is very smooth in consistency—unlike adulterated articles, mixed with potato flour and other starches of lower value, which contain larger particles.

The arrowroot starch can be used as a thickener  in many foods such as sauces, gravies, puddings, jellies, cookies, and other baked goods or pie fillings, or as a clear glaze for fruit pies. As a thickener, it is two to three times as effective as cornstarch. In Suriname, the Amerindians use the starch as a baby powder.

Arrowroot powder nutrition

The starch from arrowroot flour has a nutrition composition of 11.37% water, 0.08% ash, 21.9-29.4% amylose, 7.7% protein, 0.1% fat, 8.7% insoluble dietary fiber, 5.0% soluble dietary fiber and 15.9-33.2% resistant starch ¹¹⁾.

Table 1. Arrowroot (raw) nutrition facts

Nutrient	Unit	Value per 100 g
Approximates
Water	g	80.75
Energy	kcal	65
Energy	kJ	271
Protein	g	4.24
Total lipid (fat)	g	0.2
Ash	g	1.42
Carbohydrate, by difference	g	13.39
Fiber, total dietary	g	1.3
Minerals
Calcium, Ca	mg	6
Iron, Fe	mg	2.22
Magnesium, Mg	mg	25
Phosphorus, P	mg	98
Potassium, K	mg	454
Sodium, Na	mg	26
Zinc, Zn	mg	0.63
Copper, Cu	mg	0.121
Manganese, Mn	mg	0.174
Selenium, Se	µg	0.7
Vitamins
Vitamin C, total ascorbic acid	mg	1.9
Thiamin	mg	0.143
Riboflavin	mg	0.059
Niacin	mg	1.693
Pantothenic acid	mg	0.292
Vitamin B-6	mg	0.266
Folate, total	µg	338
Folic acid	µg	0
Folate, food	µg	338
Folate, DFE	µg	338
Vitamin B-12	µg	0
Vitamin A, RAE	µg	1
Retinol	µg	0
Carotene, beta	µg	11
Carotene, alpha	µg	0
Cryptoxanthin, beta	µg	0
Vitamin A, IU	IU	19
Vitamin D (D2 + D3)	µg	0
Vitamin D	IU	0
Lipids
Fatty acids, total saturated	g	0.039
14:00:00	g	0.002
16:00:00	g	0.035
18:00:00	g	0.002
Fatty acids, total monounsaturated	g	0.004
16:1 undifferentiated	g	0
18:1 undifferentiated	g	0.004
Fatty acids, total polyunsaturated	g	0.092
18:2 undifferentiated	g	0.074
18:3 undifferentiated	g	0.018
Fatty acids, total trans	g	0
Cholesterol	mg	0
Isoflavones
Daidzein	mg	0
Genistein	mg	0
Total isoflavones	mg	0.01

[Source: United States Department of Agriculture Agricultural Research Service ¹²⁾]

Table 2. Arrowroot flour nutrition facts

Nutrient	Unit	Value per 100 g
Approximates
Water	g	11.37
Energy	kcal	357
Energy	kJ	1494
Protein	g	0.3
Total lipid (fat)	g	0.1
Ash	g	0.08
Carbohydrate, by difference	g	88.15
Fiber, total dietary	g	3.4
Minerals
Calcium, Ca	mg	40
Iron, Fe	mg	0.33
Magnesium, Mg	mg	3
Phosphorus, P	mg	5
Potassium, K	mg	11
Sodium, Na	mg	2
Zinc, Zn	mg	0.07
Copper, Cu	mg	0.04
Manganese, Mn	mg	0.47
Vitamins
Vitamin C, total ascorbic acid	mg	0
Thiamin	mg	0.001
Riboflavin	mg	0
Niacin	mg	0
Pantothenic acid	mg	0.13
Vitamin B-6	mg	0.005
Folate, total	µg	7
Folic acid	µg	0
Folate, food	µg	7
Folate, DFE	µg	7
Vitamin B-12	µg	0
Vitamin A, RAE	µg	0
Retinol	µg	0
Vitamin A, IU	IU	0
Vitamin D (D2 + D3)	µg	0
Vitamin D	IU	0
Lipids
Fatty acids, total saturated	g	0.019
14:00:00	g	0.001
16:00:00	g	0.017
18:00:00	g	0.001
Fatty acids, total monounsaturated	g	0.002
16:1 undifferentiated	g	0
18:1 undifferentiated	g	0.002
Fatty acids, total polyunsaturated	g	0.045
18:2 undifferentiated	g	0.036
18:3 undifferentiated	g	0.009
Cholesterol	mg	0
Amino Acids
Tryptophan	g	0.004
Threonine	g	0.012
Isoleucine	g	0.01
Leucine	g	0.019
Lysine	g	0.013
Methionine	g	0.006
Cystine	g	0.006
Phenylalanine	g	0.012
Tyrosine	g	0.009
Valine	g	0.014
Arginine	g	0.012
Histidine	g	0.004
Alanine	g	0.014
Aspartic acid	g	0.047
Glutamic acid	g	0.05
Glycine	g	0.014
Proline	g	0.009
Serine	g	0.013

[Source: United States Department of Agriculture Agricultural Research Service ¹³⁾]

Table 3. Arrowroot starch nutrition facts

Nutrient	Unit	Value per 100 g
Approximates
Energy	kcal	344
Protein	g	0
Total lipid (fat)	g	0
Carbohydrate, by difference	g	87.5
Fiber, total dietary	g	3.1
Sugars, total	g	0
Minerals
Calcium, Ca	mg	0
Iron, Fe	mg	0
Sodium, Na	mg	0
Vitamins
Vitamin C, total ascorbic acid	mg	0
Vitamin A, IU	IU	0
Lipids
Fatty acids, total saturated	g	0
Fatty acids, total trans	g	0

[Source: United States Department of Agriculture Agricultural Research Service ¹⁴⁾]