July 7/Beijing/Food Business Week -- According to a study from Beijing, China, "Three soy protein isolates (SPIs) were obtained by different drying methods, including freeze-drying, spray-drying and vacuum-drying. These SPIs were found to be significantly different in color of CIELAB L*, a*, b* values, enthalpies of denaturation (Delta H) in differential scanning calorimetry, 1-anilino-8-napthalene-sulfonate surface hydrophobicities and total sulfhydryl group contents (P<0.05)."
"The solubility of spray-dried SPI was significantly higher than that of freeze-dried SPI and vacuum-dried SPI (P<0.05), except at pH 4-5. Spray-dried SPI had much lower turbidity, higher solubility and better emulsifying and foaming properties than freeze-dried and vacuum-dried SPIs," wrote X.Z. Hu and colleagues, China Agricultural University.