| Abstract
| - Rheological studies were carried out on solutions of zein in N,N-dimethylformamide (DMF), wherethe specific lot of zein, concentration, time, and temperature were varied. DMF is a good solvent forzein, giving clear, relatively low viscosity solutions. It was found that all of the zein solutions behavedin a non-Newtonian fashion. At high concentration and elevated temperature, zein solutions willincrease in viscosity with time. A temperature study on the rate of viscosity rise illustrated that attemperatures above 40 °C, the rate of viscosity rise increased in a non-Arrhenius fashion. There canbe significant lot to lot variations in commercially obtained zein that gives rise to differences in viscosityand rate of viscosity rises. With the samples studied, viscosity was found to double from one lot ofzein to another. Size exclusion chromatography suggests that compositional differences betweenthe lots drive the observed differences in viscosity. Keywords: Zein; rheology; lot variation
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