Optimization of a combined factors technology for preserving banana purée to minimize colour changes using the response surface methodology

A preservation process for banana purée based on combined factors technology was optimized using response surface methodology to minimize banana colour changes during storage of the product for at least 4 months. A Box-Behnken design was adopted and second-order polynomials models were computed for each month of storage to relate some process variables (sodium bisulphite concentration, storage temperature and thermal treatment time after packaging) to a colour function (Brown Index). It was seen that storage temperature had a highly significant effect on colour changes affecting the free bisulphite level and the browning kinetics. The optimum values of the three process variables for minimal colour development were determined.