Effect of Pasteurization on the Keeping Quality of Frozen Pitaya (Hylocereus Polyrhizus) Pulp

Abstract

Red pitaya fruit consider as attractive colour fruits since it contains bright dark colour with good taste. Many products can be produced from red pitaya such as confectionery, beverage, powder and bakery products. The attractive colour and the nutritional content possess in pitaya contribute to the acceptance of the products. The study was conducted to evaluate the best pasteurization time on the physical, antioxidant capacity, flavonoid content and microbiological aspect of pitaya pulp before being used in food formulations. Three treatments were 1 min (T1), 2 min (T2) and 3 min (T3) of pasteurization time and no treatment consider as control (T0). 3 min pasteurization time showed the highest in DPPH (2,2-Diphenyl-1-picrylhydrazyl), FRAP (Ferric Reducing Antioxidant Power) and TPC (Total Phenolic Content) assay compared to other treatments. It might be the longer time will convert the compound into other molecules which contribute to its antioxidant capacity. Meanwhile, the treatment done influence the viscosity and colour characteristic of the pitaya pulp. Pasteurization breaks the cell wall of the pulp and liberate out more active compounds in the medium. Therefore, 3 min pasteurization time is sufficient to control the appearance, enhance the active components and safety of the fruit pulp produced.