STRUCTURAL, THERMAL AND RHEOLOGICAL PROPERTIES OF NIXTAMALIZED MAIZE MASA OBTAINED FROM VARYING THE CONCENTRATION OF CALCIUM HYDROXIDE AND COOKING TIME

Juan De Dios Figueroa Cardenas, Rodolfo Rendon Villalobos, Geronimo Arambula Villa, Jesus Abraham Mendez Albores, Francisco Rodriguez Gonzalez, Rodrigo Saavedra Rosiles

Abstract: In this work, we have evaluated the effect of the concentration of calcium hydroxide (0.1 – 3.9% w/v) and cooking time (15 – 85 min) of maize grain (Pioneer 30G54 and QPM H-374C) on the structural, thermal and rheological characteristics during the nixtamalization process and compared with those without nixtamalization. The X-ray diffraction analysis of both samples of maize grain were shown to be standard type A-pattern, characteristic of most starches of cereal origin with a relative crystallinity of 44.39 – 34.12% and 42.29 –
2.51% for Pioneer and QPM, respectively. The ΔH showed values of 6.22 to 4.93
(J/g) and 5.8 to 4.24 (J/g) for both samples. The results showed that both the yield stress and the fl ow curves were influenced by the increasing calcium concentration and cooking time. The yield stress in the “masa”, increase sharply (e.g., from 2.51 to 63.10 Pa) and the viscosity signifi cantly (p < 0.05) decreased with the increasing of shear rate, due to processing conditions and that the water retention capacity increases with temperature and particle size. SEM micrographics showed that when the concentration of lime increases, agglomerates occurred only in the Pioneer sample; however, this situation is lost when the temperature varies. For QPM sample SEM micrographics showed that the nixtamalization process did not affect the granules with the increasing of calcium hydroxide.

Keywords: cooking time; nixtamalization; rheological properties; X-ray

Date published: 2017-09-08