Pitaya powder potential as antioxidant functional ingredient in food products

The use of natural pigment with additional benefits were highly appreciated by consumers. Natural active colour of pitaya fruit betalain is stable over a higher range of pH (3-9) and a better substitute for anthocyanin pigment which is easily influenced by pH changes. The objective of this study is to develop a powdered colouring made from pitaya juice. Pitaya juice was spray dried using maltodextrin with 10 dextrose equivalent (DE), 15DE and 20DE as carrier and ascorbic acid as additive to preserve the colour. The dried powder content for antioxidant and polyphenolic was evaluated using Folin-ciocalteau reagent, 2,2-diphenyl-1-picryldrazil (DPPH) and ferric reducing power (FRAP) antioxidant assay. The results showed that maltodextrin at different degree of dextrose equivalent did not show any significant difference (p > 0.05) in total phenolic content, DPPH and FRAP assay. Ascorbic acid at 0.1, 0.5 and 1.0% showed that the highest percentage of ascorbic acid content exhibited the higher (p < 0.05) total phenolic acid value of 350.4 mg gallic acid equivalent/100 g sample. DPPH and FRAP assay showed similar trend with 46.3% and 9.7 mg catechin equivalent/100 g sample. Pitaya powder with ascorbic acid has potential to be incorporated as functional ingredient into other products being developed.