STUDY of the POSSIBLE FORMATION of CALCIUM CROSS‐LINKS IN LIME TREATED (“NIXTAMALIZED”) CORN

The possible formation of calcium cross-links in lime-cooked (“nixtanalized”) corn was investigated. A 23 factorial design was utilized, with the following independent variables: lime (calcium hydroxide) dose, 1 and 3%, based on dry corn weight; cooking time, 1 and 2 h; and postcooldng holding time, 0 and 18 h. All samples were rinsed, air-dried, and ground in a hammer mill with a 40-mesh screen, and the corresponding viscoamylograms obtained. an untreated and milled (40 mesh) raw corn sample was used as control. Dependent variables were viscosities corresponding to attainment of maximum and minimum temperatures (95 and 50C) and end of holding periods at the same temperatures. Viscosities increased with increasing lime dose, decreased with increasing cooking time and were unaffected by holding time. These observations suggested that calcium cross-links were probably formed, and that degree of cross-linking increased with increasing lime dose (1 to 3%), and also with increasing cooking time (1 to 2 h).