蓝莓渗透脱水的研究

在不同的渗透温度 ( 4 5～ 65℃ )条件下 ,高果糖浆和蔗糖的有效水分扩散率 (Dm)分别为( 4 90 60～ 5 2 3 66)× 1 0 - 10 m2 /s和 ( 3 5 5 1 8～ 4 0 1 0 9)× 1 0 - 10 m2 /s,有效固形扩散率 (Ds)分别为( 2 7740～ 3 691 5 )× 1 0 - 10 m2 /s和 ( 1 3 1 63～ 2 691 5 )× 1 0 - 10 m2 /s的规律。在渗透脱水处理过程中Dm 和Ds 随处理温度升高而增加。经高果糖浆 ( 70°Brix)渗透脱水的蓝莓的平均体积比随温度升高而稍微下降。其相对密度随温度的升高也略有增加

Study on Osmotic Dehydration of Blueberries

In this study, the kinetics of moisture loss and solids gain during osmotic dehydration of blueberries under different of temperature(45～65℃) and contact time between fruit and hypertonic solution (high fructose syrup and sucrose of 70° Brix) were modeled based on Fick's law of unsteady state diffusion. the study showed that temperature influenced moisture loss and solids gain, generally showing a positive response with the increase of temperature. Based on the diffusion model, the calculated effective moisture diffusivity (D m) ranged from 4.1×10 -10 to 5.2×10 -10 m 2/s (high fructose syrup), 3.5×10 -10 to 4.0×10 -10 m 2/s (sucrose) and the effective solids diffusivity (D s) ranged from 2.7×10 -10 to 3.7×10 -10 m 2/s (high fructose syrup), 1.3×10 -10 to 2.7×10 -10 m 2/s(sucrose). Both D m and D s were increased with the increase of temperature. The average volume ratio of the osmo dehydrated blueberries in the 70° Brix high fructose syrup decreased lightly with increasing temperature during the osmotic dehydration process. However, the relative density of osmo dehydrated blueberries in the 70° Brix high fructose syrup increased lightly with increasing temperature during the osmotic dehydration process.