The effect of high voltage pulsed electric field on water molecular

Abstract

Abstract. In order to study the mechanism of high voltage pulsed electric field pretreatment on the food drying technology. In this paper, water was treated with high pulse electric field (HPEF) in different frequency, and different voltage, then, the viscosity coefficient and the surface tension coefficient of the water were measured. The results showed that indicated that the viscosity coefficient and the surface tension coefficient of the treated water can be decreased, and while HPEF pre-treatment was applied for 22.5kV at a frequency of 50Hz and 70 Hz, the surface tension and the viscosity coefficient of the pre-treatment treatment were reduced 13.1% and 7.5%, respectively. IntroductionFresh fruits and vegetables have a moisture content ranging from 75 to 90%. They are highly heat sensitive and are apt to be highly perishable. Drying is defined as the reduction of moisture from the products and is an efficient and cheap method for the preservation of fruits and vegetables. Hot air drying is one of the most commonly used procedures in dried food with main disadvantages being prolonged duration and high energy consumption. Therefore it is necessary to explore low power consumption processing for hot air drying.Dry pretreatment technology is utilized to treat food through some physical methods before drying it. Pretreatment can not only improve the quality of dried food but also increase drying rate and thus reduce energy consumption. For example, during the process of drying and dehydration for fruits and vegetables, ultrasound pretreatment certain intensity will enhance their drying rate and thus reduce the drying energy consumption [1][2][3].In recent years, a novel pretreatment technique, high voltage pulsed electric field drying pretreatment technology has been developed only recently, Angers Bach et al. showed an increase in permeability of potato tissue by high intensity electrical field pulse treatment, which resulted in improved mass transfer during fluidized bed drying [4]. Ade-Omowaye et al. found that high voltage pulsed electric field pretreatment could increase the cell membrane permeability and improve the drying rate [5]. Gachovska found that pulsed electric field treatment could increase the drying rate of carrots and enhance the quality of dried carrots [6]. Electrically assisted drying would reduce the processing time, operating temperature, and energy consumption [7]. Other papers reported similar results that pulsed electric field pretreated samples could significantly improve the drying rate [8][9].But, it is not a profoundly explored method of drying pretreatment, and, its mechanism has not been accurately determined, therefore, study the mechanisms of high voltage pulsed electric field pretreatment is one of the important theoretical basis for the technology industrialization application use.

Measurement of Apparent Electrical Impedance of Soil with Water Flow Inside

“…Electric double layers are formed in the vicinity of the surfaces of soil minerals, where negative ions are absorbed. Water flow carries positive ions in the double layer to downstream and produces a current, which is called a convection current [20][21][22]. An electrical field is also formed by the accumulated and separated charges, and this field can be modulated by the externally applied AC electric field.…”

Optimization and simulation of pulsed electric field treatment chamber for food sterilization

“…Previous studies (Zhang et al, 2016a) have pointed out that one of the most important indicators in PEF cell lysis is the magnitude of the transmembrane voltage, that is, the distribution of the electric potential in the treatment chamber and the magnitude of the electric field intensity in the treatment area are an important link to determine the rate of cell lysis, while the structure of the treatment chamber is one of the main factors to determine the distribution of electric field.…”