The process conditions were recorded during extrusion and SME
was subsequently calculated. Some variations in the extrusion
parameters were observed (Table 1) most notably the control
sample showing a higher torque value than samples containing
fruit. There were differences in the material temperature and
pressure when comparing the control to the other products, with
the SME for the control being higher than for the extrudates containing
fruit powder. Variances in SME and torque were observed in
a study of Dehghan-Shoar et al. (2010) when tomato paste powder
and skin were added to corn, rice and wheat formulations. These
variances were attributed to the lubrication effect of sugar and fibre
in the paste powder and skins. It is probable that the fruit powder
has had a similar effect but to differing degrees depending on the
sugar and fibre content of the differing powders.