Nutritional quality and technological potential of pitaya species

Abstract

Hylocereus costaricensis, H. undatus, and H. megalanthus are pitaya species produced and marketed in Brazil. The cultivation of this fruit has increased in recent years owing to its attractive appearance and sweet taste, and it may be either consumed fresh or processed for beverages and desserts. Studies on the biochemical traits and antioxidant capacity of these species can contribute to the development of new pitaya cultivars for fresh consumption and/or industrial processing. Sugars and organic acids were extracted from fruit, separated, and quantified using a chromatographic system. Total phenolic content and antioxidant capacity were quantified by spectrophotometric analysis using the Folin-Ciocalteu assay and 2,2-diphenyl-1-picrylhydrazyl radical scavenging, respectively. The data were subjected to analysis of variance and the Tukey’s test. H. undatus presented 9.83% of the total sugars, distributed as 4.75% glucose and 5.08% fructose. Total sugar concentration for H. megalanthus was 5.93%, with 0.99%, 3.25%, and 1.69% of glucose, fructose, and sucrose, respectively, and was the only species containing sucrose. The concentrations of organic acids for H. costaricensis, H. undatus, and H. megalanthus were 0.83%, 0.71%, and 0.62% for malic acid and 0.37%, 0.36%, and 0.40% for citric acid, respectively. Ascorbic acid (vitamin C) was not detected in the pulp samples. H. costaricensis had the highest content of total phenolic content and antioxidant capacity, 33.75 mg gallic acid equivalents 100 g-1 and 175.51 μmol Trolox equivalent antioxidant activity 100 g-1, respectively. Thus, the consumption of H. megalanthus fruits is recommended for people who require carbohydrate-restricted diets, although sensorially it seems to have the sweetest pulp, probably owing to the presence of sucrose. H. undatus pulp is interesting for the desserts and beverages industry owing to its high sugar content and low acidity, whereas fruits of H. costaricensis have the highest antioxidant capacity and can be used for natural food coloring.