Effect of Red Dragon Fruit ( Hylocereus polyrhizus ) Peel Powder on Physical, Antioxidative, and Sensory Properties of Biscuits

Red dragon fruit peel powder (RDPP) consists of precious phytochemicals, which could contribute greatly to the control of chronic illnesses and are still underexploited. The impacts of RDPP on the bioactive compounds, antioxidant, and sensorial properties of biscuits were investigated. The incorporation of RDPP at the amount of 1–5% caused the increase in a* value and decreases in b* and L* values of the biscuits. Moreover, higher cutting force and lower density were observed in the RDPP-enriched biscuits. The total phenolic, flavonoid, and betacyanin contents of the biscuits ranged from 0.0035 to 0.028 mg GAE/g, from 77.44 to 218.41 mg QE/g, and from 5.31 to 8.78 mg/100 g, respectively. The incorporation of RDPP in biscuits could increase the antioxidative activities. Increased appearance and overall likeness scores were recorded in the biscuits added with RDPP up to 4%. Thus, RDPP could be utilized as a nutraceutical constituent in the production of biscuit.