静电场对葡萄糖溶液和蔗糖溶液冰晶生长的影响

为了探讨静电场对糖溶液冷冻过程冰晶生长的影响,本文采用自行设计的静电场辅助冷冻实验台,以不同浓度(5、50、100、150 g/L)的葡萄糖溶液和蔗糖溶液作为研究对象,在样品冷冻过程中施加不同强度(分别为0、4、6、8、10 k V外加电压)的静电场。以过冷温度和相变时间为考察参数,分析静电场对糖溶液冰核产生和冰晶成长的影响。结果表明:不同强度的静电场对糖溶液冰晶生长的影响不同,且其影响与溶液浓度有关。对于5 g/L、50 g/L葡萄糖溶液和5 g/L蔗糖溶液,较高强度(6 k V和8 k V)静电场有促进冰核产生的影响;对于150 g/L葡萄糖溶液和蔗糖溶液,较高强度(6 k V)静电场可能对冰核产生有促进的影响。静电场对葡萄糖溶液和蔗糖溶液的冰晶成长都有抑制水分子扩散运动的不利影响。

Effects of Electrostatic Field on Ice Crystals Formation of Glucose and Sucrose Solution

The self-designed and electrostatic field-assisted freezing-equipment was used to investigate the effects of electrostatic field on ice nucleation and crystals growth in freezing process using different concentrations (5, 50, 100, 150 g/L) of glucose and sucrose solution. Different electrostatic field intensity (0, 4, 6, 8, 10 kV) was applied during the process of freeze, and super cooling temperature and phase transformation time were used as the evaluation parameters. The results showed that the effects of different electrostatic field intensity on ice growth of glucose and sucrose solution were different, which was concerned with solution concentrations. Higher electrostatic field intensity (6 kV and 8 kV) could promote the formation of ice nucleation for 5 g/L, 50 g/L glucose solution, as well as 5 g/L sucrose solution, and the higher electrostatic field intensity (6 kV) might be favorable to ice nucleation formation for 50 g/L glucose and sucrose solution. Consequently, the electrostatic field had an unfavorable effect on the diffusion of water molecules in glucose and sucrose solution in the process of ice crystals growth.