| Abstract: | Understanding the association between industrial quality and biochemical and biophysical properties of commercial maize cultivars may help breeders develop cultivars best adapted to diversified processing requirements, and processors choose cultivars best for specific requirements. The suitability of cultivars for extrusion cooking is important in this regard. To supply information useful to maize breeders and processors, biophysical (endosperm texture and hardness) and biochemical (protein and starch composition) properties of kernels, grits and extruded curls of several commercial maize cultivars were determined and related to extrusion performance. Results show that extrusion alters protein hydrophobicity and degree of aggregation, though differently between cultivars. Under conditions of this study, grits from harder maize expand more, consume less energy upon extrusion, and cook more rapidly than do grits from softer maize. These behaviors appear related to differing protein compositions and endosperm textures of cultivars. Results also suggest that reversed-phase high-performance liquid chromatography of zeins (the storage prolamin proteins of maize) may be valuable for predicting end-use properties of extruded maize products, and as a quality estimator during maize breeding. |
