| 摘要: |
| 针对高压脉冲电场处理室内电场分布不均匀,供液体流过的截面面积小的问题,对高压脉冲电场处理室进行改进。采用Laplace方程数值模拟方法,模拟改进前后处理室中的电位分布和电场强度分布;研究高压脉冲电场对啤酒酵母菌、青霉菌和大肠杆菌的杀菌效果。结果表明:当流量为30 mL/min,脉冲电场频率128 Hz,脉冲宽度17 μs,脉冲处理时间3.92 ms,电场强度为2.50、5.00、7.50、10.00、12.50和15.00 kV/cm时,改进后处理室中啤酒酵母菌、青霉菌和大肠杆菌的致死效果明显优于改进前处理室;当电场强度为15.00 kV/cm时,啤酒酵母菌、大肠杆菌和青霉菌在改进后处理室中的相对存活率仅为无法检出、0.01和0.05,而在改进前处理室则高达0.30、0.77和0.76。改进后的高压脉冲电场处理室可用于液体食品的杀菌,杀菌效果和液体流通量相对改进前的处理室均有所提高。 |
| 关键词: 高压脉冲电场 数值模拟 Laplace方程 电场分布 |
| DOI：10.11841/j.issn.1007-4333.2015.04.25 |
| 投稿时间：2014-09-03 |
| 基金项目:国家自然科学基金资助项目(31401597;31101327);2013年福建省战略性新兴产业发展专项;福建省自然科学基金项目(2013JO1084) |
|
| Research on the improvement of pulsed electric field chamber and the inactivation effect on microorganisms in liquid foods |
|
FANG Ting, WEI Qi, CHEN Jin-quan
|
| (Food Science College, Fujian Agriculture and Forestry University, Fuzhou 350002) |
| Abstract: |
| For the non-uniform distribution of electric field in the chamber of Pulsed Electric Field (PEF) and limited sectional area in chamber, the chamber of PEF was improved and the distribution of potential and electric field strength were simulated by the Laplace equation simulation.Under the conditions that flow rate was 30 mL/min, pulse electric field frequency was 128 Hz, pulse duration time was 17 μs, treatment time was 3.92 ms, and the electric field strength was 2.50, 5.00, 7.50, 10.00, 12.50 and 15.00 kV/cm, the lethal influence on Saccharomyces cerevisiae, Escherichia coli and Penicillium was obviously better in the improved chamber than that unimproved.When the strength reached 15.00 kV/cm, the relative survival rates of Saccharomyces cerevisiae, Escherichia coli and Penicillium were under the limit that could be detected, or only 0.01, 0.05 in the improved chamber;while they reached up to 0.30, 0.77 and 0.76 in the unimproved chamber.The improved chamber could be applied in liquid food sterilization as the inactivation effect and the liquid circulation were improved compared to unimproved chamber. |
| Key words: pulsed electric field numerical simulation Laplace equation electric field distribution |
