The Monodisperse Spray Drying Of The Milk Proteins And The Analysis Of The Properties Of The Products

The spray drying is a common drying method in the food processing. In theordinary spray drying system, the size of the droplets is high dispersed, the size andshape of the particles in the product are not uniform, and then the properties of theproduct will be affected. The monodisperse spray drying can producehighly similar size droplets and uniform drying particles, so the product will bedifferent. But the effect of different drying process for the characteristic of the dryingproducts of the raw milk whose component ratio (whey protein/casein) is differentand its mechanism have not been exhaustive researched.In order to better understand of this important scientific problem, optimize thedrying process and improve the product quality, this project has studied themonodisperse spray drying of the milk protein and has analyzed the characteristics ofits products. Firstly we have optimized the monodisperse drying parameters by thesingle factor experiment. By testing with the milk solution whose the concentrationis10%, we have confirmed that the driving frequency of the nozzle is7kHz and theappropriate heating temperature of the electric heating core is240?. Then bypreparing7kinds of10wt%milk protein solution with different proportion ofprotein (whey protein and casein) and12formulas composed by4components (wheyprotein, casein, lactose and maltodextrin), we have simulated the monodisperse spraydrying of the the raw milk of different component ratios and analyzed thecharacteristics of the products. Finally we have determined the granularity, the densityand the hydrability of the7milk protein powder and the product of12formulas. Theexperimental results show that, when the components of the products are the same,the particle dispersion is greater, the external density is greater. The dispersibility andthe solubility of the milk powder decrease with the increasing of the content ofcasein. The addition of lactose can increase the external density of the product, andthe addition of maltodextrin can greatly improve the dispersibility of the product. Inaddition, the lactose and malto dextrin can increase the wettability and solubility ofthe product.