The foxtail amaranth (Amaranthus caudatus L.) is one of the most popular species of domesticated amaranths. It has been cultivated for a long time as a multipurpose pseudocereal of high nutritive value, as a vegetable, and as an ornamental plant (eFloras, 2021). The plant residue after grain harvest may be fed to livestock or used for thatching.
It is mainly used as a source of food in India and South America (Agong, 2006). Known as kiwicha in Peru, its seeds are reported to be flavourful and highly nutritious and, unlike quinoa, do not contain saponins. The seeds are used to feed infants and pregnant women, disabled and elderly people (NRC, 1989). They can be used in several recipes. They produce a crunchy nutty “popcorn” when heated, they can be used as a snack, as a cold cereal with milk and honey, in sweets, or as a “breading” on chicken or fish.
The grain can be ground into flour, rolled into flakes, “puffed”, or boiled for porridge. The flour can be blended with cereal flour to improve its nutritive value (higher protein, better amino acid balance, and higher vitamin content). It enters bakery specialties. In Ethiopia, foxtail amaranth seeds are considered a famine food in times of scarcity and are combined with teff to make injera flatbread in times of abundance (Agong, 2006).
The plant contains pigments that can be used for food coloring. Young leaves and stems of foxtail amaranth can be boiled as greens, like spinach (NRC, 1989). Although they are not reported in statistics, the various amaranths may actually be the most widely grown vegetable crop in the humid tropics (NRC, 1989).
After grain harvest, the stover can be fed to livestock or used for thatching. Feed uses of the stover have been reported in South America and in other countries such as China (NRC, 1989; Brenner et al., 2000). All parts of foxtail amaranth have ethnomedicinal applications and have been reviewed for their potential benefits (anti-diabetic, anti-hyperlipidemic, anti-atherogenic, regulator of arterial pressure, cardioprotective) in human health (Martinez-Lopez et al., 2020; Agong, 2006).
Forage harvest and forage yield
After the grain is threshed, the crop residue (straw, stover) can be used as a source of fodder for cattle. Research in Peru demonstrated that it has much better nutritional value than the residues of other Andean crops. Andean farmers traditionally maintain their livestock on foxtail amaranth stover during the dry season, when forage is limited.
Amaranthus caudatus has the potential as a forage crop. It can rapidly produce a large amount of biomass with high protein content, in tropical areas where high-protein forages yield poorly (NRC, 1989). In Central Yakutia (Russia), the annual green biomass yield was 28.1 t/ha, and the DM yield was 6.44 t/ha (Maksimova, 2020).