Physico-chemical characteristics, and bioactive compounds of red fruits of sweet pitaya (Stenocereus thurberi)

Abstract

The objective of this study was to determine the physical and chemical characteristics and the content of bioactive compounds of ripe fruits of red sweet pitaya (Stenocereus thurberi). Sweet pitaya fruits are spherical, with a high moisture content (85.8%), a pulp percentage of 71.6%, soft texture (3.4 N), low acidity (0.18%), a total soluble solids content of 12.83 °Brix, with glucose and fructose being the main sugars with a content of 35.65 and 17.48 g 100 g-1 dry weight, respectively. The fruit has a low protein content (0.86% fresh weight) with tyrosine, glutamate, and methionine are the main essential amino acids. The pitaya flesh showed traces of carotenes, low content of L-ascorbic acid (12.45 mg 100 g-1 fresh weight), a content per gram of dry weight of total phenols of 11.31 mg gallic acid equivalents (GAE), total flavonoids of 13.70 mg quercetin equivalent (QE) and total betalains of 2.43 mg. The peel had a higher content of phenols and total flavonoids (5.5 and 4.3 times higher, respectively) than the flesh, which could be considered a potential source of these compounds. The red fruits of sweet pitaya can be considered a source of phenolic compounds and betalains with potential benefits to human health.