MODELING AND CONTROL OF A FOOD EXTRUSION PROCESS

This contribution reports on the process systems engineering analysis of a food extrusion process leading towards the development and implem entation of an on-line process control scheme. A versatile dynamic mod el of the process predicting the quality variables product gelatinisat ion, specific mechanical energy, specific volume and residence time ha s been developed and fitted to experimental data. The model is used to investigate the practicality of an adaptive inferential estimator (Gu ilandoust et al., 1987) for predicting infrequently measured quality v ariables on-line. The simulated performance of simple PI and model pre dictive control of these quality variables is compared.