Effect of glucose, sucrose, and lactose solution on the stability of betacyanin pigment from red dragon fruit (Hylocereus polyrhizus) peels

Abstract

People use peels, stems, leaves, and fruits of plants as a natural colorant. One part of fruit peel that has potentially used as a food colorant is red dragon fruit peels. The pigments found are betacyanin, but betacyanin compounds are easily degraded by heat, pH, and light. Degradation of betacyanin forms betalamic acid compounds (yellow) and cyclo-DOPA acids (cloroless). In this work, an attempt was made to increase the stability of betacyanin pigment against temperature by adding stabilizer such as glucose, sucrose, and lactose. Betacyanin extract was obtained from extraction using water solvent at pH 6 with a ratio of 1:4 (w/v). Extract was diluted and added stabilizer at concentration 0 ppm, 100 ppm, and 150 ppm. The solution was heated in a water bath at temperature of 60 °C for 1 hour. The content of betacyanin was examined by a UV-VIS spectrophotometer at a wavelength of 534.8 nm every 15 minutes. The retention value for 150 ppm of lactose was the greatest of all the stabilizer with the value of 61.95%. Pigment betacyanin was degraded more slowly in a lactose solution. The highest half-life time increased by 24.24% for dissolution in 150 ppm lactose. Thus, lactose has the potential to increase the stability of betacyanin.