The red-fleshed pitaya or dragon fruit (Hylocereu polyrhizus) belongs to the family of Cactaceae and order of Caryophyllales. It is also known in Chinese as huǒ lóng guǒ 火龍果 / 火龙果 “fire dragon fruit” and lóng zhū guǒ “dragon pearl fruit”.
The glabrous berry with large red scales can weigh up to 1kg. Its flesh is translucent dark-red flesh with numerous soft black seeds.
Dragon fruit is a rich source of nutrients and minerals such as vitamin B1, vitamin B2, vitamin B3 and vitamin C, protein, fat, carbohydrate, crude fiber, flavonoid, thiamin, niacin, pyridoxine, kobalamin, glucose, phenolic, betacyanins, polyphenol, carotene, phosphorus, iron and phytoalbumin.
Dragon fruit has a remarkably high content of the amino acid proline (1.1 to 1.6g/litre of the juice). Mineral content is relatively high with potassium, the most prevalent ion, followed by magnesium and calcium.
The red colour of pitaya fruit is attributed to betalains, a rare and potent class of antioxidants.
Dragon fruit is reputed to help the digestive process, prevent colon cancer and diabetes, neutralize toxic substances such as heavy metal, reduce cholesterol levels and high blood pressure.
Ruzainah Ali Jaafar, Ahmad Ridhwan Bin Abdul Rahman, Nor Zaini Che Mahmod and R.Vasudevan. Proximate Analysis of Dragon Fruit (Hylecereus polyhizus). Am. J. Applied Sci., 6 (7): 1341-1346, 2009
Stintzing F.C., Schieber A., Carle R., Phytochemical and nutritional significance of cactus pear, Eur. Food Res. Technol. 212 (2001) 396–407.
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