Nutritional composition, physical properties, and sensory evaluation of cookies prepared from wheat flour and pitaya (Hylocereus undatus) peel flour blends

Food waste produced from fruits and vegetables processing plants possesses an important natural and valuable material in producing less expensive functional food due to the presence of several bioactive substances. Therefore, the aim of the present study is to investigate the nutritional composition, physical properties, and sensory quality of the control, wheat flour cookies substituted with 5, 10, and 15% pitaya peel flour (PPF). The proximate analyses results demonstrated that PPF-containing cookies had significantly higher ash, fiber, and carbohydrate content but lower moisture and protein than the control. Physical analyses results showed that cookies incorporated with PPF had higher diameter and spread ratio but lower crumb height than the control. Sensory evaluation results indicated that wheat flour partially substituted with PPF up to 15% level did not affect to the overall acceptability ratings of cookies by panelists. Thus it can be concluded that PPF can be partially substituted for wheat flour in cookies to improve the nutritional quality without affecting the sensory acceptability of composite cookies.