Studies on effect of various operating parameters & foaming agents - Drying of fruits and vegetables

The foam mat drying is a good way of dehydrating liquids foods in short times. Due to the porous structure of the foamed materials, mass transfer is enhanced leading to shorter dehydration times. This technique can be successfully employed for drying a variety of fruit juice concentration and pulps. The dried powders have good reconstitution characteristics. These studies are particularly applicable for drying of fruit and vegetable pulps drying such as guava, bananas and tomato etc. with some of the commonly used foaming agents like egg albumin and soya protein. The drying studies are carried out in a tray drier. The drying curves are drawn with different operating parameters and foaming agents. Falling rate is observed for the foam at different timings. Drying rates are compared and the drying time is evaluated by drying the foam at 55 o C to 80 o C. These studies are helpful for evaluating best drying to get good quality dried powders.