PROVIDED IS A SOYBEAN PROTEIN MATERIAL WHICH SHOWS HIGH EMULSION STABILITY IN THE CASE WHERE 30% BY WEIGHT OF SODIUM CASEIN HAS BEEN REPLACED WITH SOYBEAN PROTEIN. A SUGAR-CONTAINING SOYBEAN PROTEIN MATERIAL IS PRODUCED BY MIXING A SOYBEAN PROTEIN RAW MATERIAL WITH A REDUCING SUGAR AND PERFORMING A HEAT TREATMENT AT A TEMPERATURE HIGHER THAN 100°C AND 170°C OR LOWER FOR 10 SEC TO 300 SEC AT PH 6.3 TO 8.0, FOLLOWED BY A HYDROLYSIS TREATMENT. FURTHER, A SUGAR-CONTAINING SOYBEAN PROTEIN MATERIAL IN WHICH PROTEIN IS CONTAINED IN AN AMOUNT OF 80% BY WEIGHT OR MORE ON A DRY WEIGHT BASIS, THE 0.22 M TCA SOLUBILITY IS 5% BY WEIGHT OR MORE, 180 µMOL OF MORE OF SUGAR IS BOUND PER G OF PROTEIN AND THE CONTENT OF β-CONGLYCININ IN PROTEIN BY THE ELISA METHOD IS 35% OR LESS, OR A SOYBEAN PROTEIN MATERIAL FOR A COFFEE WHITENER IN WHICH THE 0.22 M TCA SOLUBILITY IS 15% BY WEIGHT OR MORE AND 30% BY WEIGHT OR LESS, THE PROTEIN SOLUBILITY IS 80% BY WEIGHT OR MORE, AND THE TOTAL CONTENT OF β-CONGLYCININ AND GLYCININ BY SDS-PAGE IS 30% OR LESS USED. BY USING THESE SOYBEAN PROTEIN MATERIALS HAVING HIGH EMULSIFIABILITY, EMULSIONS AND FOODS AND DRINKS CAN BE OBTAINED.
