Microwave assisted drying of banana: effects on reducing sugars and polyphenols contents

Abstract

The effects of microwave assisted drying on banana fruit was evaluated. Water, reducing sugars, and polyphenol contents, as well as poly-phenol-oxidase activity were evaluated along the radial and axial positions in thick slices of banana, according to a properly defined cutting and assaying protocol. The effects of the microwave-assisted drying process were compared to the convective air-assisted drying resulting faster than the conventional process. In particular, the resulting samples were homogeneous in the water content; the contents of reducing sugars were strongly decreased on drying with microwaves; the poly-phenol-oxidase was inactivated by the high temperature produced by the process and thus the polyphenols content remained practically the same as in the fresh product.

Keywords

• microwave
• banana
• reducing sugar
• polyphenolpoly-phenol-oxidase