Effects of drying methods on the functional properties of flaxseed gum powders

The effects of different drying methods (spray drying, freeze drying, vacuum drying, oven drying at 80 and 105 degrees C, and ethanol precipitation) on the color and functional properties such as zeta potential, foaming, gelling, and emulsion properties of flaxseed gum were studied. Spray dried powders had the lightest color among all the powders. The powder obtained from ethanol precipitation had the lowest zeta potential and the resultant emulsion was in the most stable state. The ethanol precipitated powders had the best emulsion capacity and stability, better than even the untreated samples. The oven dried (105 degrees C) powders had the best foaming capacity and the foam stability, while the 80 degrees C oven dried powder had highest gel strength among all the dried samples. These results will be helpful in selecting suitable drying method depending on the functional properties of the flaxseed gum powders. (C) 2010 Elsevier Ltd. All rights reserved.