Study On Preparation And Influence Factors Of Yuba

Yuba is one of the soy products that making from soymilk, and the water content is no more than11%.The processing conditions and using of ultrasonic, enzyme, edible gum and starch stabilizer on yield and mechanical properties of Yuba was discussed and the interaction mechanism of acetylated distarch adipate and soymilk also. The results indicated:The optimum conditions of Yuba were:soluble solid content5%, the soluble fat/protein ratio0.2, the soluble sugar/protein ratio0.3, soymilk pH8.0and temperature85℃. Under this condition the yield of Yuba was49.02%, tensile strength3.46MPa, elongation rate11.18%, and lightness49.72. Compare to blank group, the yield of Yuba increased8.31%, tensile strength increased70.44%, elongation rate increased35.68%, and lightness increased12.59%. The physicochemical indexes meted the DBS45/005-2013<Guangxi Zhuang autonomous region local standard-bean curd, bean curd stick quality and safety requirements>.The results of ultrasonic, transglutaminase, sodium alga acid and acetylated distarch adipate on yield and mechanical properties of Yuba showed that the most significant way to increased yield and lightness were adding9g/10g of acetylated distarch adipate, the yield of Yuba was53.51%, increased18.23%to blank group, and the lightness increased25.44%. The most significant way to increased tensile strength and elongation were adding1500u/kg of transglutaminase, and0.3g/100mL sodium alga acid, the tensile strength of Yuba increased118.82%to blank group, and the elongation84.43%.Sensory evaluation score values of Yuba was optimized Yuba>acetylated distarch adipate> sodium alga acid>ultrasonic>blank group> transaminase. So adding of acetylated distarch adipate to improved the yield and mechanical properties of Yuba showed more preponderance the ultrasonic, transglutaminase and sodium alga acid.Further studies indicated:during the dyestripping of Yuba, the acetylated distarch adipate was inlayed in the interspaced of network structure developed when the protein denaturized, which made the protein film more compacted and finally mechanical capacity improved, yield increased. That may be results of joint action of hydrogen bond stabilized, sulphur content reduced, disulfide bond content, emulsification ability and surface hydrophobic increased after adding the acetylated distarch adipate.