In recent years, there has been a global trend toward the use of natural plant food components, such as: dietary fiber including soy fiber pea fiber. However, the by-product fiber moisture content (>80 %) require an efficient way to properly process it. Lately new and innovative drying methods that increase the drying rate and enhance product quality have achieved considerable attention. Microwave drying is a method that is gaining popularity due to meet the four major requirements in the drying of foods: speed of operation, energy efficiency, cost of operation, and quality of dried products.

Some natural-food enthusiasts have argued that microwaves "kill" food, breaking down its natural antioxidants. Antioxidants are substances that theoretically protect against cell-damaging free radicals in the body, and they abound in fresh fruits, vegetables , grains and nuts, according to the American Dietetic Association.

To test these concerns, a team of researchers from the Universidad Complutense Madrid in Spain got out their cutting boards. They chopped up a variety of veggies, from artichokes to zucchini, and cooked them with techniques ranging from boiling to frying to microwaving. They measured the amount of antioxidants present before and after cooking.

They found that baking, griddle-cooking and, yes, microwaving produced the lowest losses, while boiling and pressure-cooking were the hardest on antioxidants. Frying was somewhere in between.

On the other hand, microwave drying did not change lightness of food products significantly than that of fresh on. According the field test, product dried by microwaves was less brown than the conventionally oven-dried product, maybe due to faster microwave heating. These results have also been found by Arslan and Özcan (2010) who reported that microwave dried onion ,and coconut husk revealed better color values, compared with oven dried onion.

For your by-product fiber material or inhibit undesired enzymes, you could contact with us.