Pulsed Electric Field Processing: An Emerging Technology for Food
Preservation
Mahendra Pal
*
Ex-Professor of Veterinary Public Health, College of Veterinary Medicine, Addis Ababa University, Debre Zeit, Ethiopia
*
Corresponding author: Mahendra Pal, Ex-Professor of Veterinary Public Health, College of Veterinary Medicine, Addis Ababa University, Debre Zeit, Ethiopia, Tel:
091-9426085328; E-mail: palmahendra2@gmail.com
Received date: March 16, 2017; Accepted date: April 28, 2017; Published date: May 5, 2017
Copyright: © 2017 Pal M. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use,
distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
In recent years, technological revolution, nutritional awareness, and continuous demand for new generation have
necessitated the search for new techniques of food processing in industries. Pulsed electric field is one of the
emerging techniques to preserve the foods, especially the liquid ones such as milk, yoghurt, juices, soups, rice
pudding, and liquid eggs, but not suitable for solid foods. It has the potential to produce the foods with excellent
sensory and nutritional quality besides extends shelf life and ensures safety. Pulsed electric field uses short electric
pulses to preserve the foods. This technology is best suited to pasteurize heat sensitive foods. It is hoped that India
has great opportunity to develop this novel technology for the food processing. Emphasis is given to undertake
comprehensive studies on the efficacy of pulsed electric field on various bacteria and fungi, which are associated
with spoilage of foods.
Keywords: Emerging technology; Foods; Preservation; Pulsed
electric ield processing; Milk; Yoghurt
Introduction
Since ancient time, humans have used methods to preserve the food
for storing so that it can be used later to eat. A number of techniques
such as pasteurization, drying, pickling, smoking, canning, irradiation,
cooling, freezing, etc. are employed to preserve the foods from
microbial spoilage that can result into economic loss as one fourth of
world’s food supply is lost. Spoiled food becomes inedible due to
undesirable changes in the appearance, color, odor, lavor, and texture.
Microbes are widely prevalent in the environment (air, water, soil) and
can easily contaminate the food at any stage from farm to table. Hence,
preservation of food is highly imperative to ensure the safety, prevent
spoilage, extend shelf life, enhance keeping quality, control the food
poisoning and reduce economic loss [1].
Presently, many non-thermal food processing technologies such as
cold plasma, high pressure processing, irradiation, microwave heating,
ohmic heating, pulsed high intensity light, pulsed x-rays, oscillating
magnetic ield, pulsed electric ield, and high power ultrasonic are
developed to improve, replace or complement the conventionally
existing methods. hese techniques are mostly employed for liquid
foods as against solids ones, and are mostly used in large scale
production. Further, the cost of equipment’s used to impart non-
thermal processing is high as compared to equipment’s employed for
conventional thermal processing. Out of several non-thermal
processing methods, pulsed electric ield is one of the most promising
techniques, which can preserve the liquid foods by inactivation of
microbes, and also retains the nutritional and sensory attributes of
foods. his system is associated with minimum energy utilization and
greater energy eiciency than thermal processing [2]. Pulsed electric
ield is considered superior to traditional heat treatment because it
greatly minimizes the detrimental changes of the physical and sensory
properties of food [3]. Furthermore, a consumer likes to purchase the
processed food that gives fresh appearance. Application of pulsed
electric ield as a non-thermal method of food processing is gaining
popularity. It kills the vegetative cells but the texture, color, lavor and
nutrients of the food are maintained [3].
Pulsed electric ield processing is suitable for the decontamination
of heat sensitive foods. Furthermore, there is no environmental hazard,
and there is no evidence of toxicity [2]. he major constraint to employ
this technology on wider scale for the pasteurization of heat sensitive
foods is high initial investment. he engineering aspects of pulsed
electric ield processing include bench top unit, lab scale pulser and
treatment chamber. A pilot size pulser may cost approximately US
Dollar 250,000. he other units of industrial use are available at the
price of US Dollar 450,000 to 2,000,000 [2]. he aim of present
communication is to delineate briely the importance of pulsed electric
ield as novel method to preserve the foods.
Principle of Pulsed Electric Field
he basic principle of pulsed electric ield is the application of short
pulses of high electric ields with duration of micro seconds and
intensity of 10-80 kV/cm. he processing time is calculated by
multiplying the number of pulses with efective pulse duration. he use
of high voltage results in electric ield that causes the inactivation of
organisms. When an electric ield is applied, electric current lows into
the liquid food and is transferred to each point in the liquid because of
charged molecules present [4]. It is imperative that ater the treatment,
the food must be aseptically packaged and properly stored under
refrigeration to have long shelf life.
Efect of Pulsed Electric Field on Microbial Inactivation
Two mechanisms are proposed for the mode of action of pulsed
electric ield action on the microbial membrane of the organism. he
irst is electroporation in which the cell is exposed to high voltage
electric ield pulses that temporarily destabilizes the lipid bilayer and
Journal of Experimental Food
Chemistry
Pal, J Exp Food Chem 2017, 3:2
DOI: 10.4172/2472-0542.1000126
Review Article OMICS International
J Exp Food Chem, an open access journal
ISSN:2472-0542
Volume 3 • Issue 2 • 1000126