Heat-Tolerant Quinoa as a Multipurpose Crop in the Tropics

Quinoa (Chenopodium quinoa Willd.) is increasingly valued as a climate-resilient crop due to its nutritional quality and adaptability; however, there is limited information on the nutritional composition of heat-tolerant genotypes grown in tropical environments or the potential of quinoa leaves as an additional nutrient source. This study assessed the nutritional composition of leaves and grains from three heat-tolerant quinoa genotypes (Ames 13746 (Pison), Ames 13748 (Copacabana), and Ames 13745 (Kaslae)) to support their use as multipurpose crops in warm regions. Crude protein, amino acid, dietary fiber fraction, total fat, total starch, and mineral (Ca, Mg, P, K, Fe, and Zn) concentrations were quantified using AOAC, AACCI, and AOCS standardized methods. The grains exhibited a balanced essential amino acid profile, with lysine concentrations exceeding those of most staple cereals. The protein contents in the leaves and grains did not differ among genotypes (p > 0.05), although combustion analysis yielded consistently higher values than the Kjeldahl method. The leaves differed significantly in insoluble and total dietary fiber (p < 0.05), with Kaslae presenting the highest levels. In grains, the dietary fiber, total fat, total starch, and mineral contents did not vary among genotypes. The leaf mineral composition differed in terms of Ca and P, while Mg, Fe, K, and Zn levels remained similar across genotypes. These findings underscore quinoa’s potential as a nutrient-dense, multipurpose crop for food production in tropical environments.