Rheology of Stirred Yogurts

Rheological characteristics of 2 commercial brands of stirred yogurt were evaluated using a Haake Rotovisco Model RV 20 with an M‐5‐Osc measuring head and MV‐1 rotor assembly from measured shear stress values under a programmed 3‐cycle up‐ and down‐shear rate at 100 s −1 /min from 0–500 s −1 (5 min). The upward shear‐rate flow behavior of the yogurt samples could be described by a Herschel‐Bulkley model while the downward shear‐rate curves were essentially linear. Both upward and downward shear rate curves demonstrated progressive structural degradation with repeated shearing. The dependency of rheological parameters on temperature in the range 10–25°C followed both Arrhenius and Turian models.