摘要：

Rheological properties of corn starch octenylsuccinate (OSA starch) pastes (5%, w/w), at different 1-octenylsuccinic anhydride (OSA) contents (0, 1.0, 1.5, 2.0 and 2.5%, w/w) were evaluated in steady and dynamic shear. The OSA starch pastes had high shear-thinning behaviors and their flow behaviors were described by power law, Casson, and Herschel-Bulkley models. Magnitudes of consistency index ( K , K h ) and yield stress (σ oc , σ h ) increased with the increase in OSA content and the decrease in temperature. Over the temperature range of 10–50°C, the effect of temperature on apparent viscosity (η a,100 ) was described by the Arrhenius equation. The activation energy values ( E a = 10.7–13.9 kJ/mol) of OSA starches were lower than that ( E a = 15.9 kJ/mol) of native starch. Dynamic frequency sweep test showed that both storage modulus ( G ′) and loss modulus ( G ′′) of OSA starch pastes increased with the increase in OSA content. Dynamic (η * ) and steady shear (η a ) viscosities of OSA starch pastes at various OSA contents did not follow the Cox-Merz superposition rule.

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