Study on Preparation and Storage Stability of Whole Soybean Milk by High-pressure Microfluidizer

In order to avoid the production of okara in soybean milk industry, whole soybean milk (WSM)was prepared using dehulled soybeans as raw materials by high-pressure microfluidizer without filtration process, and the storage stability of WSM was also studied. Taking sensory evaluation and stability as indicators, according to single factor and orthogonal experiments, the optimum process parameters of preparing whole soybean milk were as follows: the ratio of material to water was 1:8 (w/w), the content of soluble solid was 10%, the pressure of microfluidizer was 90 MPa, the steam heating condition was 5 min at 95 ℃, the added amount of sugar was 4% and the sterilization condition was 145 ℃ for 5 s. The results of storage experiment showed that the whole soybean milk prepared by this optimized process possessed the best sensory score and excellent stability. The soymilk showed no precipitation and stratification within 90 days at 4 ℃, and the total number of bacterial colonies met the national standard of soybean milk products. According to the shelf-life calculation, it was estimated that the shelf life of WSM could reach 8 months under the storage of 4 ℃ and 3 months under the storage of room temperature (25 ℃). In summary, the optimized process could prepare a kind of WSM that was self-stable and had a good taste and flavor without filtering and adding stabilizer.