High protein, gluten-free cookies made with rice, beans and avocado

Cookies are versatile foods that can supply specific needs and can be used as food vehicles to increase the intake of various nutrients. The objective was to create a gluten-free butter cookie based on rice flour (Oryza sativa). A central composite design 2² was used for analyzing the substitution of rice flour for bean flour (Phaseolus vulgaris, L.) (0-60%) and the substitution of butter for avocado puree (Persea americana) (0-100%). Response Surface Methodology were used to analyze the data with a significance of 10% (p<0.1) and a minimum R² of 0.6. Variables analyzed were protein content (%), fat content (%), spread ratio, weight loss (%), water activity, moisture content (%), and ash content (%). Increases in the percentage of substitution of bean flour and avocado puree increased the amount of protein, ash, and moisture significantly. Fat content increased significantly following the decrease in avocado substitution. The minimum weight loss was obtained on intermediate values of bean flour. Water activity and spread ratio were not affected by changes in the variables measured. Three different formulas were obtained for the optimization: 46% bean flour and 86% of avocado puree, a formulation with an appropriate moisture range by reducing the lipid oxidation (59% bean flour and 82% avocado puree), and a formulation with 100% avocado (40% bean flour and 100% avocado puree). Sensory evaluation results of optimized treatments indicated that the formula with 46% bean flour and 86% avocado puree presented the highest global acceptance. Results from this study showcase the possibility of producing gluten-free cookies with good protein content.