A real-time
monitoring of those characteristics during processing is important to obtain a good quality of the final
product and to reduce production waste. This work investigates the measurement of rheological in-line
flow properties of tomato ketchup, using a real-time technique that combines ultrasound velocity
profiling (UVP) and pressure difference (PD) assessment. In-line data were compared to those obtained
off-line using a rotational viscometer. There was a poor correlation with the Bostwick measurement,
whereas the flow curves calculated from flow velocimetry data were very similar to those measured offline.
The extensional viscosity of ketchup was determined through the measurement of Hyperbolic
Contraction Flow; the curve