Nutrient content of micro/baby-green and field-grown mature foliage of tropical spinach (Amaranthus sp.) and roselle (hibiscus sabdariffa l.)

Abstract

Micro/baby-greens are gaining popularity in human diets as functional foods that deliver superior nutritional values and health benefits to consumers. This study conducted multiple times between 2017 and 2019 under greenhouse conditions and in the field at Rutgers University, New Brunswick, New Jersey, USA, showed that micro/baby-greens from tropical spinach (Amaranthus sp.) and roselle (Hibiscus sabdariffa L.) are rich in digestible carbohydrates, digestible protein, and dietary fiber. On dry weight basis, both vegetables have high relative percentages of P, K, and Mg; and relatively high ppm Fe, Mn, and Zn. Foliage tissues of both species are relatively low in total fat, Ca, and Cu. Between 10 and 20 days after sowing (DAS), percent digestible carbohydrates in fresh foliar tissue increased 100% in tropical spinach and 50% in roselle, while digestible protein dropped 21% in tropical spinach and 50% in roselle. Compared to field grown mature foliage, greenhouse-grown micro/baby-greens were lower in digestible carbohydrates and Ca but higher in digestible protein, P, K, Mg, Fe, Mn, and Zn.