May 2, 2025 | Food Bioscience |
Researchers from the Federal University of Pelotas and the Federal Institute of Education, Science and Technology Sertão Pernambucano, Brazil, conducted a study to evaluate the potential use of pitaya peel powder (PPP) as a natural food colorant and functional ingredient. Pitaya processing generates approximately 30% co-products, primarily peels, which are rich in dietary fiber, phenolic compounds, and betacyanins—pigments responsible for the peel’s coloration with known antioxidant properties.
The study assessed the physicochemical properties, phenolic profile, antioxidant activity, and digestibility of PPP prepared by drying pitaya peels at 60, 70, and 80 °C. All samples showed low moisture and water activity, with pH values ranging from 4.5 to 5. PPP dried at 60 °C retained the highest levels of soluble solids, betacyanins, and phenolic compounds, along with a lower darkening index, suggesting better preservation of color and bioactive compounds.
Although samples dried at 70 and 80 °C showed reduced betacyanin content, they maintained high antioxidant activity due to preserved phenolics. PPP dried at 60 °C demonstrated stability across pH 3–7 and showed strong coloring potential in food hydrocolloid systems such as cassava starch and gelatin over 7 days of storage.
The findings support PPP as a promising natural alternative to synthetic food colorants, with added functional benefits.
