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Traditional salad have high amount of egg yolk and oil, resulting in the "high calorie,high fat, high cholesterol," which has aroused people’s attention. Soybeans is rich in fiber anda variety of nutrition composition, if soybean can be the main raw material of salad, thehealth problems can be solved. The experiment is based on lower egg yolks and oil, treatsoybean as the main raw material of salad dressing with high fiber, through the optimizationof the process, formulation and shelf life, making a soybean salad that can stored at roomtemperature.First, studied on the technological process of soybean salad, determined the rapid stirringspeed, stirring time and homogeneous Ⅲ time. Through single factor experiment, theoptimum process parameters were: fast mixing speed is900rpm, stirring Ⅰ (5min)+mixing Ⅱ (5min)+mixing Ⅲ (15min), slow stirring300rpm/5min, colloid millhomogeneous time9min.Second,improved the formula of salad.Determined the formula through the single factorand orthogonal experiment,the formula were:soybean9.5%,salad oil13%,egg yolk power9%,thickening agent0.4%,water56.5%(40%of soybean milk,16.5%of ingredients),canesugar9.2%,citric acid0.4%and salt2%.The salad made by this formula is similar tocommercially salad in aspect of rheological,texture and viscosity.Again, salad is oil content food, so fat oxidation will occur in storage that will affect theshelf life,the antioxidants compound with inhibition of soybean salad dressings during thestorage was tested, determined the amount of adding antioxidants to: TBHQ0.15g/kg+BHT0.05g/kg. With the antioxidant content, the fat oxidation kinetics model was established,the model can predict the normal temperature(25℃) shelf life, the predicted results showedthat based on the theory of lipid oxidation, shelf life is249days at room temperature(25℃).Finally, in salad dressing’s microbial shelf life study, determined the amount of addedpreservatives as: Nisin0.08g/kg+potassium sorbate0.268g/kg+EDTA disodium0.015g/kg.On this basis, established the microbial growth model of salad dressing under differentstorage temperature, through the growth model of delay time under different temperature andthe maximum growth rate, predicted their relationship with the temperature from4℃to25℃, Within the scope of this article, the comparison of measured and predicted valuesshowed that the error between predicted values and measured values are within10%. Inaddition, combined with the shelf life in room temperature storage of TPA, sensory, andcoliform bacteria,eventually determined the salad dressing’s shelf life at room temperature(25℃) is4months.
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