| In this paper, the preparation of single vegetable juice, the formulation of mixed vegetable and fruit juice, the adjustment of taste and flavor, the improvement of cloudy stability, the physiochemical properties including rehylogy, colorimetry and the general oxidative stability were studied.In the improved technics of carrot juice, the carrot was kept in steam chamber (65℃)for 70min before and blanched with citric-Vc solution at 100℃ for 5min. The new blanching conditions (pH8.5, Zn2+ 0.05%, 85℃, Imin) were determined to protect the greenness during extraction of vegetable juice such as cucumber.The mixed fruit-vegetable juice (hereafter named mixed juice) was prepared, from apple, tomato, wax gourd, carrot and six kinds of green vegetables namely celery, cucumber, caraway, cabbage, cole and spinach. Two kinds of formulas of mixed juice, PDHL (9-mixed) and PDHFL (10-mixed), were determined through the mixture design of SAS Software. The method of the designing formula of mixed juice or food was generalized from the application of SAS Software.Then, PDHL beverage, with ginger juice 1.0%, honey1.0%, CMC-Xanthan Gum (2:1) compound stabilizer 0.15% and VeltolPlus 10mg/kg added and homogenized under 25 MPa, was made. The final product showed pH 3.8 and 癇rix 8, and kept good cloudy stability.The physiochemical data proved more information for its possible industrialization, such as the data on rehylogy, colorimetry study and general oxidative stability. PDHL beverage appeared Non-Newtonian fluid, and holded pseudoplastic flow profile of shear thinning; its viscosity decreased with the increase of temperature. Different kinds of color were shown when P, D, H, L four basic elements had different proportions in the whole system. However the sensory scores changed linearly with the value of L*, a*, b*. The digesting test in the situation of simulated gastric juice testified that the comprehensive oxidative stability of PDHL juice was stronger than any other juice.
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