Application of High-Intensity Pulsed Electrical Fields in Food Processing

High-intensity pulsed electric fields (HIPEF) treatment is gaining popularity as a nonthermal processing technology due to its instant penetration characteristics and short processing time. It is evolving as a potential alternative to other thermal and chemical unit operations in food processing. In recent years, numerous research groups have demonstrated the possibility of inactivation of a range of microorganisms and food quality-related enzymes. This article focuses on the potential to use the HIPEF treatment as a preservation technology and as an adjunct to other processing steps, such as extraction, osmotic dehydration, air dehydration, and rehydration.     

高压脉冲电场杀菌技术研究进展

高压脉冲电场用于食品杀菌具有时间短、能耗低,能有效保存食品营养成分和天然色、香、味特征,具有广阔的工业化应用前景,本文从高压脉冲电场处理系统设计、灭菌机理、处理效果、影响因素、能量消耗与经济性等方面对其研究现状和工业化应用前景做了探讨。     

Review: Potential of High Hydrostatic Pressure and Pulsed Electric Fields for Energy Efficient and Environmentally Friendly Food Processing

The application of emerging, novel processing techniques such as high hydrostatic pressure or pulsed electric fields can be utilized to replace, enhance or modify conventional techniques of food production. In addition to quality improvements and consumer benefits by gentle microbial inactivation and improvement of mass transfer processes, their potential to improve energy efficiency and sustainability of food production will be discussed within this review.     

Review: Potential of High Hydrostatic Pressure and Pulsed Electric Fields for Energy Efficient and Environmentally Friendly Food Processing

The application of emerging, novel processing techniques such as high hydrostatic pressure or pulsed electric fields can be utilized to replace, enhance or modify conventional techniques of food production. In addition to quality improvements and consumer benefits by gentle microbial inactivation and improvement of mass transfer processes, their potential to improve energy efficiency and sustainability of food production will be discussed within this review.     

脉冲电场技术在食品工业上的应用进展

当前食品工业加工方法主要依赖于传统的热处理与化学方法,这些方法往往会对食品质量和安全性产生负面影响,且存在高成本、环境不友好等弊端,开发高效、绿色的食品加工方法已成为食品业界亟待解决的难题。脉冲电场(Pulsed Electric Field,PEF)技术是一种利用高电压振幅的电磁脉冲对物料进行处理的物理方法,作为一种新兴的非热加工技术,PEF技术因其独特的优势吸引了广大学者对其进行广泛而深刻的讨论,以期将其应用于食品工业。该研究综述了脉冲电场技术的原理、应用机制,包括电穿孔理论、电流体、等离子体以及电化学反应与自由基激活假说,并对其在食品工业上的应用进行总结与归纳,为食品加工领域提供了有效的解决方法,有利于推动脉冲电场技术在食品加工领域的发展与应用。     

Apricot Nectar Processing by Pulsed Electric Fields

Application of pulsed electric fields to process apricot nectar by determining the pH, °Brix, total acidity, conductivity, color, non-enzymatic browning index, concentration of mineral ions, and retention of ascorbic acid and beta carotene as well as inactivation of Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus, Pseudomonas syringae subs. syringae, Erwinia carotowora, Penicillum expansum, and Botrytis cinerea was explored in this study. Processing of apricot nectar did not cause a significant difference in measured attributes (p > 0.05). However, inactivation of all microorganisms was significantly increased with increased electric field strength and treatment time (p ≤ 0.05). Microbial inactivation data fit both the Weibull distribution and log-logistic model.     

高压脉冲电场在食品灭菌方面的研究现状及展望

高压脉冲电场杀菌能保持食品的原有风味和营养成分,具有处理时间短、能耗低的特点.介绍了高压脉冲电场的杀菌机理、处理系统、影响因素、处理效果及其经济性这五个方面,并展望其在食品灭菌方面的应用前景.     

高压脉冲电场杀菌技术在紫菜食品加工中的应用

高压脉冲电场(PEF)用于食品杀菌具有时间短、能耗低、能有效保存食品营养成分和天然色、香、味特征,非常具有工业化前途。本文是高压脉冲电场(PEF)在食品杀菌中的实践及它在工业生产加工中的应用。鲜紫菜加工厂应用PFE杀菌的技术工艺过程,设备的选型,参数设计。以往高压脉冲电场(PEF)技术多数停留在实验研究阶段,实际生产中的应用不多,此项目是对高压脉冲电场(PEF)杀菌技术的集成实施,从生产反馈中获得优化数据,有较好的推广前景。     

高压脉冲电场杀菌技术在食品工业中的应用

食品杀菌是食品处理过程中的一个重要环节。高压脉冲电场杀菌因其杀菌时间短、效率高、能耗少等特点在食品灭菌中发挥着越来越重要的作用,综述了高压脉冲电场杀菌机理、特点、杀菌效果和在食品工业中不同方面的应用。并对此技术的发展前景提出了展望。     

Microbial and Enzymatic Changes in Fruit Juice Induced by High-Intensity Pulsed Electric Fields

High-intensity pulsed electric fields (HIPEF) treatment is a nonthermal technology that has been studied in the last few years as an alternative to heat treatments. It consists of applying pulses of high electric field (kV/cm) during a short time (μsec or msec) at low or moderate temperature.

Because of their properties, fruit juices are appropriate products to be processed by HIPEF. Studies on the effects of HIPEF on microorganisms show that this treatment destroys microorganisms at levels of heat pasteurization with lower destruction of vitamins, flavor compounds, and other micronutrients. The majority of enzymes that are responsible for adverse biological reactions in fruit juices are inactivated by HIPEF. The effects of HIPEF, as for thermal treatments, are mainly described by first-order models. Furthermore, others models are also proposed to fit some effects of HIPEF on the enzymatic activity or microorganisms population. Fewer works are focused on the effects on organoleptic, physical, and chemical properties of fruit juices, but results show that most of the properties remain unchangeable. The changes, if they occurred after a HIPEF treatment, are always less important than those produced by heat.     

高压脉冲电场在食品工业中的应用

介绍了高压脉冲电场应用于食品工业。高压脉冲电场(HPEF)是一种低能耗、高效率的食品加工技术,在杀菌,干燥,保持风味和营养成分等方面,HPEF技术都表现很好的效果。     

高压脉冲电场非热杀菌技术对原料乳的预处理

针对国内原料乳质量低下这一问题,运用高压脉冲电场非热杀菌技术对原料乳进行预处理。发现原料乳的细菌总数随电场强度、脉冲数、初始温度的增加而降低,随流速的增加而升高。当出口温度为常温20℃,电场强度E=50kv/cm,脉冲频率为1000Hz,流速为20ml/min时,能使其菌落总数降低2.6个数量级,从四级原料乳提升至一级原料乳,且不改变其营养结构和风味。     

Effects of High-Intensity Pulsed Electric Fields on Lipoxygenase and Hydroperoxide Lyase Activities in Tomato Juice

ABSTRACT:  The influence of high-intensity pulsed electric field (HIPEF) parameters, namely, pulse frequency, pulse width, and polarity on tomato juice lipoxygenase (LOX) and hydroperoxide lyase (HPL) activities was studied using a response surface methodology. Samples were subjected to square-shaped pulses of 35 kV/cm for 1000 μs, with pulse width ranging from 1 to 7 μs at frequencies from 50 to 250 Hz, either in monopolar or bipolar mode. Tomato LOX was more resistant to HIPEF than HPL within the range of assayed conditions. An increase in frequency or pulse width resulted in a decrease of both residual LOX ( RA_LOX ) and HPL ( RA_HPL ) activities. The lowest  RA_LOX  (81%) was observed when tomato juice was treated at 250 Hz for 7 μs in bipolar mode. Moreover, the same conditions led to the highest HPL activity reduction ( RA_HPL  = 10%). A validation of the predictive models determined that 2nd-order expressions were accurate enough to fit the experimental results.     

高压脉冲电场对酵母和大肠杆菌的杀灭效果

研究了高压脉冲电场的电场强度和脉冲时间对胡萝卜汁中接种的啤酒酵母 (CGM CC 2 60 4)和大肠杆菌 (CGMCC 1 90 )的杀灭效果。结果表明 ,啤酒酵母和大肠杆菌的残活率都随着电场强度的增大和脉冲时间的延长而逐渐下降 ,同轴式电极中 ,在 2 3kV的电压和1 2 42ms的脉冲处理时间下 ,酵母达到最小残活率 -4 113个对数 ;平板电极中 ,在 17kV/cm的电场强度和 0 45ms的脉冲处理时间下 ,大肠杆菌达到最小残活率 -2 3 97个对数。同时发现 ,酵母对电场强度和脉冲时间的敏感程度大于大肠杆菌。     

Quality-Related Enzymes in Plant-Based Products: Effects of Novel Food Processing Technologies Part 2: Pulsed Electric Field Processing

Pulsed electric field (PEF) processing is an effective technique for the preservation of pumpable food products as it inactivates vegetative microbial cells at ambient to moderate temperature without significantly affecting the nutritional and sensorial quality of the product. However, conflicting views are expressed about the effect of PEF on enzymes. In this review, which is part 2 of a series of reviews dealing with the effectiveness of novel food preservation technologies for controlling enzymes, the scientific literature over the last decade on the effect of PEF on plant enzymes is critically reviewed to shed more light on the issue. The existing evidence indicates that PEF can result in substantial inactivation of most enzymes, although a much more intense process is required compared to microbial inactivation. Depending on the processing condition and the origin of the enzyme, up to 97% inactivation of pectin methylesterase, polyphenol oxidase, and peroxidase as well as no inactivation have been reported following PEF treatment. Both electrochemical effects and Ohmic heating appear to contribute to the observed inactivation, although the relative contribution depends on a number of factors including the origin of the enzyme, the design of the PEF treatment chamber, the processing condition, and the composition of the medium.     

Commercial-Scale Pulsed Electric Field Processing of Orange Juice

Effects of commercial‐scale pulsed electric field (PEF) processing on the microbial stability, ascorbic acid, flavor compounds, color, Brix, pH, and sensory properties of orange juice were studied and compared with those of thermal processing. Freshly squeezed orange juice was thermally processed at 90 °C for 90 s or processed by PEF at 40 kV/cm for 97 ms. Both thermally processed and PEF‐processed juices showed microbial shelf life at 4 °C for 196 d. PEF‐processed juice retained more ascorbic acid, flavor, and color than thermally processed juice (P<0.05). Sensory evaluation of texture, flavor, and overall acceptability were ranked highest for control juice, followed by PEF‐processed juice and then by thermally processed juice (P<0.01).     

高压脉冲电场杀菌电力系统的研究

高压脉冲电场用于液态食品杀菌 ,具有时间短、能耗低 ,能有效保存食品营养成份和天然色、香、味特征 ,非常具有工业化应用前途。本文重点介绍高压脉冲电场杀菌电力系统的结构特点和应用。     

Food Processing by Pulsed Electric Fields: Treatment Delivery, Inactivation Level, and Regulatory Aspects

Industrial implementation of pulsed electric field electro-technology (PEF) for food preservation has been rather slow, despite its potential to produce safe, nutritious and high-quality products. Several research groups around the world are in a race to validate and optimize the operation of PEF systems. Insufficient kinetic studies and inaccurate treatment delivery assessment are some of the main obstacles to the implementation of this technology. Equivalency among PEF systems, treatment delivery and control variables need to be clearly defined before actual industrial implementation takes place. Limited commercial availability of PEF systems, mainly due to the complexity and high cost of pulsers, and to technical and economical limitations of the scaling-up process, reflects into high initial investment and operation costs. This paper reviews the state of the art on the above-mentioned issues, and also discusses engineering, biological, and regulatory aspects that should be considered for optimization and commercial implementation of PEF as a food preservation technology.     

高压脉冲电场对百合混汁灭菌的研究

研究了高压脉冲电场(PEF)对百合混汁的灭菌效果。操作过程中电场强度和处理时间是影响其灭菌效果的主要参数,随着电场强度的增大和处理时间的延长,灭菌效果越来越好。当电场强度达到30 kV/cm时,灭菌效果非常显著,处理时间为400μs时菌落总数已降低了4个对数值。经PEF处理后,百合混汁的理化指标没有明显的变化,可以保持其原有品质。     

高压脉冲电场对大肠杆菌胞内蛋白的影响

通过聚丙烯酰胺凝胶电泳和傅里叶变换红外光谱研究了高压脉冲电场(PEF)处理对大肠杆菌(E.coli)胞内蛋白的影响,并应用去卷积和曲线拟合等数学方法和圆二(CD)色谱进一步分析PEF处理前后蛋白二级结构中α-螺旋、β-转角、β-折叠和无规卷曲相对含量的变化。结果表明,经过PEF(30 kV/cm,400μs)处理后,在分离胶的顶端出现了蛋白质的聚集。蛋白二级结构中β-折叠相当含量从45.40%降至21.50%,β-转角相对含量从23.8%降至8.81%,而无规卷曲结构从0.13%升至36.95%,α-螺旋结构没有明显的变化。