The effects of manothermosonication on tomato pectic enzymes and tomato paste rheological properties

摘要

The effect of manothermosonication (MTS), the simultaneous application of heat and high energy ultrasound waves under moderate pressure, on tomato juice rheology and on tomato pectinmethylesterase (PME) and polygalacturonase (PG) activity in tomato juice was examined. Tomato juice was subjected to MTS treatments (20 kHz, 2 kg pressure, 117 μm amplitude and 70 deg. C), or to control thermal treatments (TT), for 1 min. Flow curves, yield stress and apparent viscosity were measured on both kind of samples. Apparent viscosity of MTS samples were 1.6-fold higher than that of TT samples.