The effect of temperature and toasting time of blue maize was evaluated to develop and optimize a pinole mixture. For toasting, total anthocyanins (TA), polyphenols (TP), antioxidant activity (AA), color, viscosity, and microscopic analysis of starch were determined. With the best conditions, a pinole formulation was developed by adding amaranth, chickpea, chia, and oat through a D-optimal mixture design. High temperature and toasting time decreased the TA, TP, lightness, and viscosity; and increased the AA, color (a*, b*), and starch damage. Toasting at 200°C for 4.5 min was adequate, with TA, color (a*), and viscosity retention of 55.68%, 86.83%, and 81.11%, respectively. All four ingredients had significant effects and the special cubic model described the nutritional, physicochemical, functional, and rheological properties. Optimum pinole mixture (1.0% amaranth, 4.97% chickpea, 7.80% chia, and 4.63%) based on reaching the maximum contents of protein, fiber, AA, and TP, had better properties than a local blue maize pinole.

Novelty impact statement

This study informs about the importance of establishing the temperature and time conditions for toasting blue maize in order to obtain a base of toasted maize for the formulation of pinole with minimal losses of bioactive compounds and color, but with adequate physical and rheological properties. In addition, contributes to the development of a blue maize pinole with ingredients that improve its color, nutritional, rheological, and functional properties; representing an alternative of healthy consumption.