Improved Functionality of Food Additives with Electrostatic Coating

Electrostatics is widely used in the snack food industry as an alternative to traditional powder coating. The purpose o f this study is to determine whether electrostatics improves the functionality of different food powders and to evaluate the mechanisms involved in the process. French fries were coated at 0kV and -25kV with smoke extract or glucose and mozzarella cheese slices with sodium erythorbate or cellulose with natamyacin. French fries were evaluated based on color and the cheese slices were evaluated on appearance o f mold. Transfer efficiency was higher for all electrostatically coated products except for powdered cellulose on cheese. This effect was removed by comparing samples that had the same amount o f powder. Electrostatically coated samples showed a greater color development and less mold growth than nonelectrostatically coated samples for the same amount o f powder. This improvement in color and shelf life could be explained by improvement in evenness. Charge to mass ratio was larger for all powders electrostatically charged except cellulose. The particle size, flowability and size distribution may also contribute to the efficiency of the electrostatic coating. Small, free flowing powders with narrow size distribution showed the biggest improvement in color and shelf life while large, cohesive powders with wide size distribution had the least. Powder mixtures with flow agents or that have the tendency to tribocharge during transportation have decreased overall charge received by the powder particles. Cellulose with natamyacin did not show an improvement in transfer efficiency, mold suppression or charge to mass ratio with electrostatic coating.