Effects of different drying methods on solubility of whole egg powder

To improve the quality and solubility of whole egg powder, the effect of five different drying methods (heated-air drying, vacuum freeze drying, microwave drying, spray-drying, far-infrared drying) on nutrition constituent and key evaluation indexes about solubility such as wetting sinking time，hydratability，coefficient of solubility，agglomerate rate and stability were evaluated. The results indicated that whole egg powder made by spray-drying has the highest nutrition retention rate and the best solubility, wetting sinking time was 198.24 s, hydratability was 4.8516 mL/g, coefficient of solubility was 1.8525 (revolving speed:140 r/min), agglomerate rate was 18.08 %, and coefficient of stability was 81.91%. Egg powder particles presented as spongy porous structure and its condition most likely to be original status. The quality and solubility of whole egg powder by vacuum freeze drying was inferior to that of made by spray-drying, and then the whole egg powder made by far-infrared drying and microwave drying. The whole egg powder made by heated-air drying has the lowest nutrition retention rate, the worst solubility, obviously shrinkage and agglomeration. Overall, it could be found that whole egg powder made by spray-drying has the best quality. This could provide a theory basis for producing instant whole egg powder.