Investigating the effect of adding palm kernel flour on gluten-free cookie based on rice flour

Dates are one of the oldest fruit trees grown in warm and subtropical regions of the world. Each year in date-producing countries, a significant amount of palm kernel is produced as a byproduct in palm fruit processing. Due to its significant amounts of carbohydrates, vitamins, minerals and fiber, as well as low cost and ease of access, date palm kernel has been considered today as a functional source of high economic justification for food products. In this research, this by- product was used in the production of functional cookies. So that the effect of replacing 0 to 30 percent of date palms flour in the formula on the moisture, ash, raw and diet fiber content, phenolic compounds, antioxidant properties, colorimetric indices, firmness and sensory properties of treatments, was investigated. The results of this study indicate that increasing the replacement of palm kernel flour increased ash, phenolic compounds, antioxidants, fiber types, total acceptance, texture firmness and color index a *, and also reduced the moisture content and the index L * and b *. The evaluation of the findings especially the taste, showed that the replacement of palm kernel flour up to 20% caused producing high-quality, nutritious and durable cookies.