Physico-chemical properties and quality assessment of corn flour processed by a continuous ohmic heating system and traditional nixtamalization

Abstract

Traditional nixtamalization is performed to produce corn flour and tortillas. This process has undergone several modifications for industrialization purposes. Extrusion is an industrially used process for nixtamalization and ohmic heating may be considered an alternative. For this study, a continuous ohmic heater was used to produce nixtamalized corn flour and the effects of the process parameters – process temperature, feed moisture, and screw speed – on the physicochemical and textural properties of dough and tortilla were reviewed. Data showed that the process temperature had a greater effect than the feed moisture on the resulting product, while screw speed did not appear to have any significant influence on this. Tortillas showed good quality characteristics because of good water absorption and retention during the process. The products obtained by continuous ohmic heating process show quality characteristics similar to those present in traditional corn flour products.