Effect of drying methods for inner parameters of red beetroot (Beta vulgaris L.)

In compliance with consumer expectations, careful processing and preservation are increasingly used with fruits and vegetables. The aim is that during these treatments the valuable nutritional characteristics of the raw materials change as little as possible. Drying has been used for the preservation of raw materials for a long time, which can distinguish two different groups based upon pressure. These are the atmospheric and the more careful vacuum drying.

During the research, Alto F1 beetroots were being dried in vacuum and under atmospheric pressure at different temperatures. Vacuum drying took place at 40, 50, and 60 °C, while atmospheric drying at 60, 70, and 80 °C. All drying processes lasted 150 minutes. During drying, changes of moisture content and water activity were monitored. After drying, colour measurement was realized and the inner parameters were investigated, such as polyphenol, betalain, and antioxidant capacity. These measured parameters were compared in the ease of atmospheric and vacuum drying.