Effect of lime content on the processing conditions of cooked maize tortillas: changes of thermal, structural, and rheological properties

Basic data on thermal, dielectric, and IR spectral properties of cooked tortillas were investigated with the major aim to understand the role of lime, Ca(OH)2, incorporated during the alkaline cooking process. The data are further supplemented by x-ray diffraction and texture mea- surements. The changes in the thermal diffusivities, measured by the photoacoustic technique, as well as the changes in texture, x-ray pat- terns, dielectric, and IR spectral properties are presented as a function of the lime concentration. The results show strong evidence that there is a marked concentration of lime (around 0.2%) above and below which different behavior patterns of the measured properties of tortilla were observed. In particular, the results for the dielectric constant and thermal diffusivity provide strong evidences for enhanced starch crosslinking tak- ing place for lime content close to 0.2%.