Optimization of microwave drying conditions of two banana varieties using response surface methodology
Food Science and Technology
Dptimization of microwave drying conditions of Luvhele and Mabonde banana varieties were studied using response surface methodology. The drying was performed using a central composite rotatable design for two variables: microwave power level (100, 200 and 300 W) and drying time (40, 26, and 12 min.) for Luvhele; (100, 200 and 300 W) and (42, 27, and 12 min) for Mabonde. The colour and texture (hardness) data were analyzed using ANDVA and regression analysis. The fitness of the models obtained
... s good as the lack of fit for each of the models was not significant. The coefficient of determination R 2 of the models was relatively high, hence the models obtained for the responses were adequate and acceptable. Drying conditions of 178.76 W, 12 min. drying time were found optimum for product quality at a desirability of 0.91 for Luvhele; while 127.67 W, 12 min. with a desirability of 0.86 was predicted for Mabonde. The result of this study could be used as a standard for microwave processing of Luvhele and Mabonde banana varieties. Practical Application: Drying refers to the removal of moisture from a material with the primary aim of reducing microbial activity and product deterioration. Drying of agricultural products offer other advantages such as reduced packaging, handling, storage and transportation costs. Microwave drying has advantages of high drying rates, high energy efficiency, better product quality and efficient space utilization. Response surface methodology has important application in the design, development and formulation of new products, as well as in the improvement of existing product design.