Predicting fillability of viscoelastic product in Tetra Recart

It is of interest to design a methodology in predicting the fillability of non-Newtonian viscoelastic product such as meat batter by analyzing its rheological properties, reducing the need to perform pilot plant scale tests. Meat batter with different added water produced in laboratory and pilot plant were analyzed to represent meat batters with different rheological characteristics and filling behaviour. The analysis of the rheological properties of the samples were performed in duplicates using rotational rheometer. The rheological tests done include flow curve determination, build-up test, break down test, and amplitude sweep test. The results showed that the meat batter had shear thinning time-dependent property (thixotropy) and could be described by Power Law at shear rate range 1-200s-1 which was applicable to the filling machine. The calculated K value, apparent viscosity, and calculated Pressure drop derived from the model showed decreasing trend as the % water increased, which could provide information on the limit of the machine. On the other hand, the trend of n value which ranged from 0.10-0.15 was not dependent on the % added water. The samples with lower added water was found to have higher thixotropy and elastic property compared to those of more added water, which influenced its fillability. The samples were tested in the filling machine to study the pressure profile curves. Samples which were able to be filled showed a steady state region and followed a viscous fluid behaviour. The prediction model was found to have a good estimation of the experimental pressure drop value for higher water added meat batter. In conclusion, the calculated K value and amplitude sweep test can be used to predict the meat batter’s fillability in the filling machine with a standard tank. For products which exceeded the limit, the filling machine with pressurized tank can be recommended.