Convective Air Drying Characteristics and Qualities of Non-fried Instant Noodles

Abstract

Abstract Convective air drying characteristics and qualities of non-fried instant noodles at five temperatures from 80 to 120°C and velocities of 1.0, 2.0 and 3.0 m/s were investigated. Different mathematical models were fitted to study the drying behaviors and the Logarithmic model was the most adequate in describing the drying tests. Results showed that the drying process occurred in a falling rate periods and the effective moisture diffusivity increased with temperature and velocity, ranging from 4.41×10−8 to 1.75×10−7 m2/s with an activation energy of 16.73 kJ/mol. The rehydration attributes changed with both velocity and temperature. Increasing temperature and velocity decreased hardness, increased cohesiveness and resilience generally while had no impact on springiness. Drying temperature greatly influenced the color of noodles, whereas velocity displayed no significant effect. Microstructural analysis indicated that noodle presented hollow and porous structure with numerous and small voids, which might partly explain their distinct behaviors.