真空、脉冲真空和常压下蓝莓渗透脱水的研究

Study on Osmotic Dehydration of Blueberries at Vacuum Pressure,Pulsed Vacuum and Atmosphere Pressure

研究了真空渗透脱水、脉冲真空渗透脱水和常压渗透脱水下蓝莓水分含量和水分活度的变化规律,结果表明:真空渗透脱水时,蓝莓的水分含量和水分活度降低得最快。真空渗透脱水、脉冲真空渗透脱水、常压下渗透脱水蓝莓的有效水分扩散率分别为1.6777×10-9、1.3629×10-9、0.5679×10-9m2/s。真空渗透脱水、脉冲真空渗透脱水、常压下渗透脱水的有效固性物扩散率分别为9.1705×10-10、6.3919×10-10、5.1007×10-10m2/s。

In this experiment, the moisture content and water activity of blueberries during osmotic dehydration at vacuum pressure, pulsed vacuum and atmosphere pressure were studied. The results showed that the moisture content and water activity of blueberries during osmotic dehydration at vacuum pressure fell down most quickly. The effective moisture diffusivity （Dm） of blueberries during osmotic dehydration at vacuum pressure, at pulsed vacuum and at atmosphere pressure respectively 1.6777 ×10^-9, 1.3629×10^-9 and 0.5679 ×10^-9m^2/s. The effective solids diffusivity （Ds） of blueberries during osmotic dehydration at vacuum pressure, at pulsed vacuum and at atmosphere pressure were 9.1705 ×10^-10, 6.3919 ×10^-10 and 5.1007 ×10^-10m^2/s, respectively.