Abstract

ORTEGA-MOODY, Jorge; MORALES-SANCHEZ, Eduardo; HERNANDEZ-ROMAN, Miguel Ángel  and  RUIZ-TORRES, Maximiano. Sistema para producir harina nixtamalizada con transporte de bajo cizallamiento. Ingenier. mecáni. tecnolog. desarroll [online]. 2011, vol.4, n.1, pp.033-042. ISSN 1665-7381.

The tortilla is the most widely consumed food product in Mexico and is produced through the traditional process of Nixtamal. This method has two down-sides: the first is the amount of contaminated water that the process generates (Nejayote); the second is the time loss generated by a batch-based production system. As a possible solution to this various methods have been developed that are based principally in extrusion. Through heat extrusion the product is converted in a fluid pseudo-plastic due to the fact that the product is being cooked at the same time as it is being sheared and transported. This causes the viscosity of the cornmeal to be altered. In response to this problem, this investigation presents a system that transports and cooks cornmeal with specific quantities of water and calcium in order to obtain the nixtamal. The stages of transport contain a low shear screw that is connected to the rectangular oven by way of a geometric adapter. The rectangular oven was designed according to the rheological and thermal properties of the cornmeal. Consequently, the geometry obtained suits the cooking process and offers a laminate flow in order to diminish the amount of shearing during the cooking process.

Keywords : Nixtamal process; low shear; mechanical design; cornmeal; simulation.