ABSTRACT
In Mexico, alkali cooking called “nixtamalization” is extensively used to improve maize texture and nutritional value. From maize nixtamalization, “nixtamal” is obtained, which is good to produce soft dough and “nejayote,” which is the wastewater generated from this process. During maize nixtamalization, the arabinoxylans (AXs) present in the maize cell wall are partially hydrolyzed generating low molecular weight AX. A nixtamalization process with prolonged lime soaking could result in more effective polysaccharide 380hydrolysis; however, to the best of our knowledge, the characteristics of AX generated by different maize lime soaking time have not been investigated elsewhere. In the present study, AX recovered from nejayote after 6 (AX6) or 12 h (AX12) of maize lime soaking presented a molecular weight of 74 and 57 kDa and ferulic acid content of 0.14 and 0.10 µg/mg polysaccharide, respectively. The intrinsic viscosity and arabinose to xylose ratios of AX6 and AX12 were 206 and 161 mL/g and 0.55 and 0.53, respectively. Both AX formed covalent gels induced by laccase. The storage modulus (G′) AX6 and AX12 at 8% (w/v) were 4 and 2 Pa, respectively. These results indicate that an increase in lime soaking from 6 to 12 h during maize nixtamalization reduces the AX molecular size and ferulic acid content which forms, therefore, less elastic gels.
