Pulsed Electric Field (PEF) applications can be utilised to achieve disintegration of biological tissues or microbes. Various applications have been identified such as improvement of mass transfer during extraction or drying as well as gentle food preservation. The first commercial applications of the technique have been achieved. By development of equipment based on state of the semiconductor, equipment reliability and cost effectiveness of the equipment has been improved. The technology is heading for wider industrial application.
This document discusses pulsed electric field (PEF) technology. PEF uses short electric pulses to preserve foods without heat, maintaining fresh qualities and nutrients. It can extend shelf life while ensuring safety. PEF works by applying high-intensity pulses that cause microbial cell membranes to break down without significantly heating the food. PEF has various applications, including pasteurizing juices and milk. It provides advantages like minimal processing, color/flavor retention, and higher nutritional value compared to thermal treatments.
Radio frequency processing and Microwave heating in food processing prakashsp13
radio frequency and microwave heating ; these slides are explain about its principle and working mechanism ,application in food processing and its advantages .
W.A. Mihiravi Pamuditha gave a presentation on radio frequency (RF) heating technology for food processing. RF heating uses electromagnetic energy to induce volumetric heating within foods. It has advantages over conventional heating like faster and more uniform heating. Some applications of RF heating in food include thawing, baking, drying, pasteurization and using RFID tags for tracking. While it has benefits, high equipment costs are a disadvantage. The future of RF technology may include its expanded use in continuous food processing and integration with technologies like nanotechnology and smart refrigerators.
This document discusses pulsed electric field (PEF) processing as a non-thermal food preservation technique. PEF uses short, high-voltage electric pulses to induce pores in microbial cell membranes, leading to cell disintegration and microbial inactivation while minimizing negative impacts on sensory and nutritional properties. The document outlines various PEF applications, factors that influence microbial inactivation, commercially available PEF systems, ongoing research needs, and the potential future of PEF processing.
Pulsed Electric Field Processing of FoodStella Mariem
The document discusses various process factors that affect microbial inactivation using pulsed electric fields, including electric field intensity, temperature, pressure, and time of exposure. It explains that increasing any of these factors leads to greater inactivation. It also notes different pulse wave shapes that can be used, and describes how the high voltage electric field pulses cause electroporation, making cell membranes permeable and leading to cell death.
This document discusses microwave technology in food applications. It begins by describing the properties of microwaves, including their wavelength and frequency approved for food. It then explains how microwaves are absorbed by polar molecules in food, causing heating through molecular friction. Microwave heating is described as uniform throughout the food, unlike conventional heating which occurs from the surface in. Several food applications of microwaves are listed, including baking, cooking, drying, and enzyme inactivation. The document concludes by noting the magnetron is commonly used to generate microwaves in microwave ovens and tunnel ovens.
This document discusses pulsed electric field (PEF) technology. PEF uses short electric pulses to preserve foods without heat, maintaining fresh qualities and nutrients. It can extend shelf life while ensuring safety. PEF works by applying high-intensity pulses that cause microbial cell membranes to break down without significantly heating the food. PEF has various applications, including pasteurizing juices and milk. It provides advantages like minimal processing, color/flavor retention, and higher nutritional value compared to thermal treatments.
Radio frequency processing and Microwave heating in food processing prakashsp13
radio frequency and microwave heating ; these slides are explain about its principle and working mechanism ,application in food processing and its advantages .
W.A. Mihiravi Pamuditha gave a presentation on radio frequency (RF) heating technology for food processing. RF heating uses electromagnetic energy to induce volumetric heating within foods. It has advantages over conventional heating like faster and more uniform heating. Some applications of RF heating in food include thawing, baking, drying, pasteurization and using RFID tags for tracking. While it has benefits, high equipment costs are a disadvantage. The future of RF technology may include its expanded use in continuous food processing and integration with technologies like nanotechnology and smart refrigerators.
This document discusses pulsed electric field (PEF) processing as a non-thermal food preservation technique. PEF uses short, high-voltage electric pulses to induce pores in microbial cell membranes, leading to cell disintegration and microbial inactivation while minimizing negative impacts on sensory and nutritional properties. The document outlines various PEF applications, factors that influence microbial inactivation, commercially available PEF systems, ongoing research needs, and the potential future of PEF processing.
Pulsed Electric Field Processing of FoodStella Mariem
The document discusses various process factors that affect microbial inactivation using pulsed electric fields, including electric field intensity, temperature, pressure, and time of exposure. It explains that increasing any of these factors leads to greater inactivation. It also notes different pulse wave shapes that can be used, and describes how the high voltage electric field pulses cause electroporation, making cell membranes permeable and leading to cell death.
This document discusses microwave technology in food applications. It begins by describing the properties of microwaves, including their wavelength and frequency approved for food. It then explains how microwaves are absorbed by polar molecules in food, causing heating through molecular friction. Microwave heating is described as uniform throughout the food, unlike conventional heating which occurs from the surface in. Several food applications of microwaves are listed, including baking, cooking, drying, and enzyme inactivation. The document concludes by noting the magnetron is commonly used to generate microwaves in microwave ovens and tunnel ovens.
Ultrasonication processing of fruits and vegetables Gundewadi
1) Sonication is an alternative non-thermal technology to traditional heat processing of fruit juices that provides benefits such as less processing time, higher nutrient retention, and being more energy efficient.
2) Studies have shown that sonication of fruit juices for durations of 30-60 minutes can increase levels of antioxidants like polyphenols and carotenoids while reducing microbial loads.
3) The mechanism of action involves cavitation bubbles forming during sonication that cause cell membrane disruption in microorganisms leading to inactivation without heat.
NOVEL Food Processing Technologies: Emerging Applications, Research and Regul...senaimais
This document summarizes emerging food processing technologies and their applications, research, and regulations. It discusses the AAFC Food Safety Research pilot plant in Guelph, Canada, which was certified in 2011 to conduct food safety engineering research. It reviews available groups of food processing technologies, including thermal, non-thermal, and combined technologies. Key drivers for these technologies include freshness, convenience, safety, shelf-life extension, and sustainability.
1) The document presents a case study on tomato peeling using ohmic heating with lye-salt combinations. Experiments were conducted to determine the effects of electric field strength and salt-lye composition on peeling time and the diffusion of sodium hydroxide through the tomato peel.
2) Results showed that treatments with 0.01/0.5% NaCl/NaOH at 1610 V/m and 0.01/1.0% NaCl/NaOH at 1450 V/m had the shortest peeling times. Diffusivities for lye peeling with ohmic heating were greater than without at both 50 and 65°C.
3) It was concluded that the electric field enhances
Non thermal processing of food- Pulsed electric field and visible lightT. Tamilselvan
This document provides information on pulsed electric field (PEF) and pulsed visible light processing of foods. PEF uses short electric pulses to preserve foods through electroporation of microbial cell membranes, while minimizing heat production. PEF has been shown to effectively inactivate various microbes in foods like milk, eggs and juices. Pulsed visible light also uses intense, brief pulses of light to inactivate microbes in foods photochemically and through localized heating. Both techniques are non-thermal alternatives to traditional food processing that reduce degradation of nutritional and sensory qualities compared to heat treatments.
High pressure processing (HPP) is a method of preserving and sterilizing food, in which a product is processed under very high pressure, leading to the inactivation of certain microorganisms and enzymes in the food
pulse electric field for food processing technologyMaya Sharma
Pulse electric field (PEF) technology uses high voltage electric pulses to permeabilize microbial and plant cell membranes. It can be used as a non-thermal pasteurization method for foods like juices. PEF systems generate short pulses of 15-80 kV/cm for under 1 second using pulse-forming networks and fast switches. This disrupts microbial and plant cell membranes through electroporation. PEF can inactivate bacteria and yeasts while maintaining sensory and nutritional properties of foods. It has potential applications in juice, dairy, meat, and plant oil extraction processing. However, PEF is not effective against spores and requires further research toward commercialization.
Hurdle technology for food preservationDeepak Verma
This document discusses hurdle technology, which uses a combination of preservation methods at optimal levels to inhibit microorganisms without compromising food quality. It explains that hurdle technology combines physical hurdles like heat treatment, freezing or modified atmosphere with physic-chemical hurdles like low pH, salt or preservatives. Some examples given are pickles which use acid and salt, and sausages which employ smoke, salt and preservatives. The advantages of hurdle technology are maintaining food safety, quality and nutrition while allowing for minimally processed foods.
This document provides an overview of high pressure processing (HPP) of foods. HPP uses high pressure, around 400-600 MPa, to inactivate pathogens and microorganisms while minimally affecting the food's qualities. HPP retains food quality by preserving nutrients, texture, taste and appearance. It has applications for foods like meats, seafood, juices, sauces, dairy products and more. The advantages of HPP are that it achieves uniform microbial reduction without heat, maintains sensory qualities and is more environmentally friendly than thermal processing. The document discusses the basic principles, history, equipment, generation of pressure, applications and advantages and disadvantages of HPP.
Pulsed electric field (PEF) processing is an emerging non-thermal food preservation technology. PEF technology is established on the utilization of electric fields to remove food-borne pathogens and to subjugate the spoilage microorganisms in foods. This technology is notably acknowledged for its capability to amplify the mean life of food products without the utilization of heat also preserving the quality aspects such as sensory and nutritional attributes, together with enabling the safety of food products
Radio frequency heating is an emerging technology for food processing that uses electromagnetic energy between 1-300 MHz to induce volumetric heating. It has advantages over conventional and microwave heating such as faster and more uniform heating. The seminar discussed the principles, mechanisms, factors affecting, and applications of RF heating in food industries like thawing, pasteurization, drying, and baking. Research shows RF heating effectively inactivates pathogens in fruit juices, milk, meat and spices without negatively impacting quality.
Pulsed electric field (PEF) technology uses short, high voltage electric pulses to induce pores in cell membranes, causing microbial inactivation and cell disintegration without significantly heating the food. This allows for longer shelf life and fresh quality retention compared to thermal pasteurization. PEF works by exceeding the critical transmembrane potential of cells, typically around 10 kV/cm for E. coli. It is effective against vegetative microbes and can reduce microbial loads by 4-6 logs but has limited effectiveness against spores, viruses or enzymes. PEF is suitable for liquid, semi-liquid and some solid foods but requires expensive equipment and refrigeration to extend shelf life.
Microwaves are electromagnetic waves with wavelengths between 1 mm and 1 m that are used for heating. Microwave ovens generate microwaves at a frequency of 2.45 GHz to heat food through rotation and ionic conduction, causing more efficient heating than conventional methods. The key components of a microwave oven are the magnetron which generates microwaves, the waveguide which directs the waves, and the cooking cavity where food is placed. Microwaves are also used for industrial applications like pasteurization, sterilization, drying and heating materials.
High pressure processing is a non-thermal food processing technique that uses high pressures, usually between 100-1000 MPa, to inactivate microorganisms and extend the shelf life of foods. It has minimal effects on taste, texture, color, and nutrients of foods. HPP is being used commercially for products like guacamole, sliced meats, seafood, juices, and dairy to kill pathogens and spoilage microbes while maintaining quality. The high pressure is applied uniformly from all directions using a pressure vessel filled with water, which compresses the packaged foods within minutes and safely destroys microbes without heat.
Hurdle technology involves using two or more preservation methods together to inhibit microbial spoilage of foods. It allows for safer, stable foods without refrigeration. Common hurdles include reduced pH, increased salt content, reduced water activity, and heat processing. The hurdles work synergistically by disturbing the microbes' homeostasis. This technique is widely used in products like jam, fermented vegetables, meat, fish, and dairy. It improves safety and quality while reducing costs compared to using single preservation methods. However, some limitations exist in fully understanding and applying hurdle effects in practice.
Ohmic heating is a novel thermal food processing technique that uses electricity to rapidly and uniformly heat foods. It works by passing electricity through food materials, which act as resistors and generate heat. Key advantages are uniform heating from 1-100°C/s without hot surfaces, higher nutrient retention, and simpler controls than conventional heating methods. Ohmic heating has applications in meat processing, dairy pasteurization, fruit and vegetable blanching, and thawing. Further research is needed to address limitations such as potential metal contamination from electrolysis and difficulties heating non-conductive foods very high or low in moisture.
Ohmic heating is an advanced thermal processing method that uses direct resistance heating to heat food products. It works by passing an electric current through the food, with the food itself serving as the resistor to generate heat. Ohmic heating allows for rapid and uniform heating throughout the product at rates of 1-100°C/s. It has advantages over conventional heating like reduced nutrient loss, uniform heating, and faster processing times. Some potential applications of ohmic heating in food processing include meat processing, milk pasteurization, fruit and vegetable blanching, and waste water treatment. However, further research is still needed to fully understand and control the process and address issues like preventing electrolysis during heating.
Ankit Kumar presents information on novel food processing techniques. He provides details about his background and qualifications. The document then discusses several innovative processing methods including microwave heating, ohmic heating, irradiation, pulsed electric fields, and high pressure processing. It provides explanations of how each technique works and its advantages for food processing applications.
Pulsed electric field (PEF) technology uses short, intense electric pulses to non-thermally pasteurize liquids and semi-liquid foods. PEF systems generate high voltage pulses between electrodes to irreversibly break down microbial cell membranes. PEF processed foods maintain fresh qualities like flavor, color and nutrients since no heat is used. While PEF can extend shelf-life, products are generally refrigerated for safety or quality. PEF is a promising alternative to thermal pasteurization for heat-sensitive foods.
Pulsed electric field (PEF) technology uses short, intense electric pulses to non-thermally pasteurize liquids and semi-liquids like milk, juice, and soup. PEF systems generate high-voltage pulses between electrodes to irreversibly break down microbial cell membranes. PEF processing maintains fresh qualities like taste, color and nutrients since it does not use heat. While PEF can extend shelf-life, products are generally refrigerated for safety or quality. Commercial scale PEF systems can process thousands of liters per hour.
Ultrasonication processing of fruits and vegetables Gundewadi
1) Sonication is an alternative non-thermal technology to traditional heat processing of fruit juices that provides benefits such as less processing time, higher nutrient retention, and being more energy efficient.
2) Studies have shown that sonication of fruit juices for durations of 30-60 minutes can increase levels of antioxidants like polyphenols and carotenoids while reducing microbial loads.
3) The mechanism of action involves cavitation bubbles forming during sonication that cause cell membrane disruption in microorganisms leading to inactivation without heat.
NOVEL Food Processing Technologies: Emerging Applications, Research and Regul...senaimais
This document summarizes emerging food processing technologies and their applications, research, and regulations. It discusses the AAFC Food Safety Research pilot plant in Guelph, Canada, which was certified in 2011 to conduct food safety engineering research. It reviews available groups of food processing technologies, including thermal, non-thermal, and combined technologies. Key drivers for these technologies include freshness, convenience, safety, shelf-life extension, and sustainability.
1) The document presents a case study on tomato peeling using ohmic heating with lye-salt combinations. Experiments were conducted to determine the effects of electric field strength and salt-lye composition on peeling time and the diffusion of sodium hydroxide through the tomato peel.
2) Results showed that treatments with 0.01/0.5% NaCl/NaOH at 1610 V/m and 0.01/1.0% NaCl/NaOH at 1450 V/m had the shortest peeling times. Diffusivities for lye peeling with ohmic heating were greater than without at both 50 and 65°C.
3) It was concluded that the electric field enhances
Non thermal processing of food- Pulsed electric field and visible lightT. Tamilselvan
This document provides information on pulsed electric field (PEF) and pulsed visible light processing of foods. PEF uses short electric pulses to preserve foods through electroporation of microbial cell membranes, while minimizing heat production. PEF has been shown to effectively inactivate various microbes in foods like milk, eggs and juices. Pulsed visible light also uses intense, brief pulses of light to inactivate microbes in foods photochemically and through localized heating. Both techniques are non-thermal alternatives to traditional food processing that reduce degradation of nutritional and sensory qualities compared to heat treatments.
High pressure processing (HPP) is a method of preserving and sterilizing food, in which a product is processed under very high pressure, leading to the inactivation of certain microorganisms and enzymes in the food
pulse electric field for food processing technologyMaya Sharma
Pulse electric field (PEF) technology uses high voltage electric pulses to permeabilize microbial and plant cell membranes. It can be used as a non-thermal pasteurization method for foods like juices. PEF systems generate short pulses of 15-80 kV/cm for under 1 second using pulse-forming networks and fast switches. This disrupts microbial and plant cell membranes through electroporation. PEF can inactivate bacteria and yeasts while maintaining sensory and nutritional properties of foods. It has potential applications in juice, dairy, meat, and plant oil extraction processing. However, PEF is not effective against spores and requires further research toward commercialization.
Hurdle technology for food preservationDeepak Verma
This document discusses hurdle technology, which uses a combination of preservation methods at optimal levels to inhibit microorganisms without compromising food quality. It explains that hurdle technology combines physical hurdles like heat treatment, freezing or modified atmosphere with physic-chemical hurdles like low pH, salt or preservatives. Some examples given are pickles which use acid and salt, and sausages which employ smoke, salt and preservatives. The advantages of hurdle technology are maintaining food safety, quality and nutrition while allowing for minimally processed foods.
This document provides an overview of high pressure processing (HPP) of foods. HPP uses high pressure, around 400-600 MPa, to inactivate pathogens and microorganisms while minimally affecting the food's qualities. HPP retains food quality by preserving nutrients, texture, taste and appearance. It has applications for foods like meats, seafood, juices, sauces, dairy products and more. The advantages of HPP are that it achieves uniform microbial reduction without heat, maintains sensory qualities and is more environmentally friendly than thermal processing. The document discusses the basic principles, history, equipment, generation of pressure, applications and advantages and disadvantages of HPP.
Pulsed electric field (PEF) processing is an emerging non-thermal food preservation technology. PEF technology is established on the utilization of electric fields to remove food-borne pathogens and to subjugate the spoilage microorganisms in foods. This technology is notably acknowledged for its capability to amplify the mean life of food products without the utilization of heat also preserving the quality aspects such as sensory and nutritional attributes, together with enabling the safety of food products
Radio frequency heating is an emerging technology for food processing that uses electromagnetic energy between 1-300 MHz to induce volumetric heating. It has advantages over conventional and microwave heating such as faster and more uniform heating. The seminar discussed the principles, mechanisms, factors affecting, and applications of RF heating in food industries like thawing, pasteurization, drying, and baking. Research shows RF heating effectively inactivates pathogens in fruit juices, milk, meat and spices without negatively impacting quality.
Pulsed electric field (PEF) technology uses short, high voltage electric pulses to induce pores in cell membranes, causing microbial inactivation and cell disintegration without significantly heating the food. This allows for longer shelf life and fresh quality retention compared to thermal pasteurization. PEF works by exceeding the critical transmembrane potential of cells, typically around 10 kV/cm for E. coli. It is effective against vegetative microbes and can reduce microbial loads by 4-6 logs but has limited effectiveness against spores, viruses or enzymes. PEF is suitable for liquid, semi-liquid and some solid foods but requires expensive equipment and refrigeration to extend shelf life.
Microwaves are electromagnetic waves with wavelengths between 1 mm and 1 m that are used for heating. Microwave ovens generate microwaves at a frequency of 2.45 GHz to heat food through rotation and ionic conduction, causing more efficient heating than conventional methods. The key components of a microwave oven are the magnetron which generates microwaves, the waveguide which directs the waves, and the cooking cavity where food is placed. Microwaves are also used for industrial applications like pasteurization, sterilization, drying and heating materials.
High pressure processing is a non-thermal food processing technique that uses high pressures, usually between 100-1000 MPa, to inactivate microorganisms and extend the shelf life of foods. It has minimal effects on taste, texture, color, and nutrients of foods. HPP is being used commercially for products like guacamole, sliced meats, seafood, juices, and dairy to kill pathogens and spoilage microbes while maintaining quality. The high pressure is applied uniformly from all directions using a pressure vessel filled with water, which compresses the packaged foods within minutes and safely destroys microbes without heat.
Hurdle technology involves using two or more preservation methods together to inhibit microbial spoilage of foods. It allows for safer, stable foods without refrigeration. Common hurdles include reduced pH, increased salt content, reduced water activity, and heat processing. The hurdles work synergistically by disturbing the microbes' homeostasis. This technique is widely used in products like jam, fermented vegetables, meat, fish, and dairy. It improves safety and quality while reducing costs compared to using single preservation methods. However, some limitations exist in fully understanding and applying hurdle effects in practice.
Ohmic heating is a novel thermal food processing technique that uses electricity to rapidly and uniformly heat foods. It works by passing electricity through food materials, which act as resistors and generate heat. Key advantages are uniform heating from 1-100°C/s without hot surfaces, higher nutrient retention, and simpler controls than conventional heating methods. Ohmic heating has applications in meat processing, dairy pasteurization, fruit and vegetable blanching, and thawing. Further research is needed to address limitations such as potential metal contamination from electrolysis and difficulties heating non-conductive foods very high or low in moisture.
Ohmic heating is an advanced thermal processing method that uses direct resistance heating to heat food products. It works by passing an electric current through the food, with the food itself serving as the resistor to generate heat. Ohmic heating allows for rapid and uniform heating throughout the product at rates of 1-100°C/s. It has advantages over conventional heating like reduced nutrient loss, uniform heating, and faster processing times. Some potential applications of ohmic heating in food processing include meat processing, milk pasteurization, fruit and vegetable blanching, and waste water treatment. However, further research is still needed to fully understand and control the process and address issues like preventing electrolysis during heating.
Ankit Kumar presents information on novel food processing techniques. He provides details about his background and qualifications. The document then discusses several innovative processing methods including microwave heating, ohmic heating, irradiation, pulsed electric fields, and high pressure processing. It provides explanations of how each technique works and its advantages for food processing applications.
Pulsed electric field (PEF) technology uses short, intense electric pulses to non-thermally pasteurize liquids and semi-liquid foods. PEF systems generate high voltage pulses between electrodes to irreversibly break down microbial cell membranes. PEF processed foods maintain fresh qualities like flavor, color and nutrients since no heat is used. While PEF can extend shelf-life, products are generally refrigerated for safety or quality. PEF is a promising alternative to thermal pasteurization for heat-sensitive foods.
Pulsed electric field (PEF) technology uses short, intense electric pulses to non-thermally pasteurize liquids and semi-liquids like milk, juice, and soup. PEF systems generate high-voltage pulses between electrodes to irreversibly break down microbial cell membranes. PEF processing maintains fresh qualities like taste, color and nutrients since it does not use heat. While PEF can extend shelf-life, products are generally refrigerated for safety or quality. Commercial scale PEF systems can process thousands of liters per hour.
Pulsed electric field (PEF) technology uses short electric pulses to preserve foods in a non-thermal manner. PEF involves applying high-intensity electric pulses of microseconds to milliseconds to foods placed between electrodes, causing microbial inactivation through irreversible cell membrane breakdown. PEF has been successfully used to pasteurize various liquid foods like juices, milk, and soups without degrading quality, though it is limited to pumpable liquids without air bubbles smaller than the treatment gap. PEF is a continuous process that provides a fresh-like alternative to thermal pasteurization for heat-sensitive products.
Pulsed electric field (PEF) technology uses short pulses of high-intensity electric fields to preserve foods. It offers advantages over thermal pasteurization like shorter treatment times, lower temperatures, and better retention of sensory and nutritional properties. PEF works by creating pores in microbial cell membranes, killing bacteria and extending shelf life. It has been used successfully to pasteurize various liquids like juices, milk, and soups without chemical preservatives. PEF processing also has applications in improving mass transfer for oil extraction, meat curing, sugar processing and extraction of compounds from algae and plant cells. However, high capital costs and inability to process solid foods limit its commercial use.
This document summarizes a seminar presentation on pulsed electric field (PEF) food processing. PEF uses short pulses of electricity to preserve foods without heat, extending shelf life while maintaining quality. It can pasteurize liquids like juice and milk. The document discusses the history of PEF, how it works using electric fields to inactivate microbes, applications in juice and other foods, advantages like minimal nutrient loss, and limitations like only working on liquids. PEF is a promising non-thermal food processing technique still under development.
This presentation summarizes pulsed electric field (PEF) technology. PEF involves applying high-voltage electric pulses between electrodes to food for less than one second. This minimizes energy loss from heating. PEF induces pores in cell membranes through electroporation, inactivating microbes without detrimental effects to food quality. A square pulse generator uses capacitors, inductors, and solid state switches to produce the high-voltage pulses. Processing factors like electric field strength, temperature, time of exposure, and pulse shape influence microbial inactivation during PEF. PEF improves the shelf life of foods like bread, milk, fruit juices, and more through more efficient microbial inactivation than conventional heat treatment.
High voltage pulse technique or High intensity pulsed electric field processing involves the application of electric pulses of high voltage
20-80 kV/cm to the food placed between two electrodes.
The applied electric field create a pores on the cell membrane, thus the phenomenon known as Electroporation or electropermeabilization.
The effect of Electroporation can be divided into four steps:
An increase in the transmembrane potential
Pore formation
Evolution of the number and size of the pores
Pore resealing
Pulse electric field processing technologyMusiigeDenis
This document provides information about pulsed electric field (PEF) technology, including:
1. PEF uses short electric pulses to preserve foods while maintaining fresh quality and nutrients. It kills microbes through electroporation without significantly heating the food.
2. The principles of PEF involve applying high-voltage pulses between electrodes to create an electric field that makes microbe cell membranes permeable, causing death. Factors like pulse strength and time affect treatment effectiveness.
3. Studies show PEF effectively kills bacteria, yeasts and molds in orange juice with reductions of 2-6 log, extending its shelf life while retaining quality. It is a promising non-thermal method for food preservation.
FDA - kinetics of microbial inactivation for alternative food processing tech...Wouter de Heij
This document discusses pulsed electric fields (PEF) technology for non-thermal food preservation. PEF involves applying high-voltage electric pulses to foods placed between electrodes. Studies show PEF can effectively inactivate microbes in foods like apple juice, orange juice, milk, eggs, and pea soup. PEF preserves quality attributes better than thermal processing. However, challenges remain in scaling up equipment and handling issues like air bubbles. Future research is still needed on chemical effects and expanding applications.
Food processing transforms raw ingredients into marketable products through physical or chemical means. Key processing methods include drying, freezing, addition of preservatives, and canning. Emerging non-thermal technologies include pulsed electric fields, high pressure processing, ultrasound, and supercritical fluid extraction. These methods inactivate pathogens and extend shelf life while better retaining nutrients, flavors, and colors compared to thermal processing. Non-thermal processing is gaining popularity for commercial food production due to these advantages.
The document discusses pulsed electric fields (PEF) technology for food processing and preservation. PEF uses short pulses of high voltage electricity to inactivate microorganisms through electroporation and electrical breakdown of cell membranes. The document outlines the history, mechanisms, system components, factors affecting treatment, and applications of PEF for juices, beverages, dairy, eggs, meat and other foods. PEF is presented as a non-thermal alternative to traditional heating methods that can improve food safety, quality and extraction of nutrients and compounds.
Kinetics of microbial inactivation for Pulsed Electric Field (PEF, PurePulse)...CoolWave Processing b.v.
Pulsed electric fields (PEF) can be used to non-thermally preserve foods by inactivating microbes. PEF involves applying short pulses of high voltage electricity to food between electrodes. This disrupts microbial cell membranes, killing bacteria while avoiding significant heating and quality changes to foods. The document discusses PEF mechanisms and research on its effectiveness in reducing microbes in various foods like apple juice, orange juice, milk, eggs and pea soup. It also covers factors like pulse waveform, equipment design and limitations of the technology.
High-intensity pulsed electric field(PEF) processing involves the application of pulses of high voltage(typically 20-80 kV/cm) to foods placed between two electrodes.
It is an efficient non-thermal food processing technique using short, high-voltage pulses.
These pulses induce poration of plant, animal, and microbial cells, leading to cell disintegration and microbial inactivation.
Products have a longer shelf life whilst maintaining better nutritional value than traditional food processing techniques.
Pulsed Electric Field (PEF) processing uses high-voltage electric pulses to rupture the cell membranes of microorganisms and enzymes in liquids, killing harmful cells. PEF can be used to treat foods, wastewater, and biofuels, preserving qualities like taste and nutrients since no heat is used. DTI has developed commercial-scale PEF systems for food processing up to 50,000 liters/hour and wastewater treatment at 10,000 liters/hour, reducing biosolids volume by 50% and increasing methane production by 75%.
Processing and Preservation by Non-thermal Methods.pdfshahin211118
This document discusses various non-thermal food processing methods including ohmic heating, pulsed electric fields, high pressure processing, pulsed light, ultrasound, oscillating magnetic fields, and irradiation. It describes the objectives and mechanisms of each method, providing details on how each technique works to reduce microbes while maintaining quality attributes like color, flavor and texture. The conclusion states that non-thermal methods are useful for liquid foods and large-scale production but have high equipment costs, and that reducing costs could enable broader application in small industries.
high intensity pulsed electric field processingpptxKhushbu Kumari
The document discusses high intensity pulsed electric field (PEF) processing. PEF uses short pulses of electric fields to inactivate microbes in foods. A PEF system consists of a high voltage generator, switch, capacitor and electrodes. PEF generates pulses of electric fields that create pores in microbial cell membranes, killing the microbes. Square wave pulses are most effective for inactivation. The document also describes a pilot-scale integrated PEF and aseptic system for orange juice processing that achieved 99.9% microbial reduction while better retaining juice quality than heat pasteurization.
Pulsed Electric Fields for Food Processing Technology-ppt.pptxMaduni3
Pulsed electric fields (PEF) is a non-thermal food preservation technique that uses short, high-voltage electric pulses to inactivate microorganisms. PEF disrupts microbial cell membranes, causing leakage of intracellular contents and loss of ability to grow. It can pasteurize liquids like juice and milk with less effect on quality than heat. A PEF system consists of a power supply, capacitors, switches, pulse generator, and treatment chamber. PEF is used for applications like juice extraction enhancement and microbial inactivation in fruits and liquids. It allows for extended shelf life without heat-induced quality changes.
Pulsed Electric Fields for Food Processing Technology-ppt.pptxMaduni3
Pulsed electric fields (PEF) is a non-thermal food preservation technique that uses short, high-voltage electric pulses to inactivate microorganisms. PEF disrupts microbial cell membranes, causing leakage of intracellular contents and loss of ability to grow. It can extend shelf life of foods like juice and milk without negatively impacting quality. A PEF system consists of a power supply, capacitors, switches, pulse generator, and treatment chamber. PEF is used to pasteurize liquid and semi-solid foods below 40°C and can also enhance extraction of bioactives from plant cells.
Maruthi Prithivirajan, Head of ASEAN & IN Solution Architecture, Neo4j
Get an inside look at the latest Neo4j innovations that enable relationship-driven intelligence at scale. Learn more about the newest cloud integrations and product enhancements that make Neo4j an essential choice for developers building apps with interconnected data and generative AI.
Pushing the limits of ePRTC: 100ns holdover for 100 daysAdtran
At WSTS 2024, Alon Stern explored the topic of parametric holdover and explained how recent research findings can be implemented in real-world PNT networks to achieve 100 nanoseconds of accuracy for up to 100 days.
UiPath Test Automation using UiPath Test Suite series, part 6DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 6. In this session, we will cover Test Automation with generative AI and Open AI.
UiPath Test Automation with generative AI and Open AI webinar offers an in-depth exploration of leveraging cutting-edge technologies for test automation within the UiPath platform. Attendees will delve into the integration of generative AI, a test automation solution, with Open AI advanced natural language processing capabilities.
Throughout the session, participants will discover how this synergy empowers testers to automate repetitive tasks, enhance testing accuracy, and expedite the software testing life cycle. Topics covered include the seamless integration process, practical use cases, and the benefits of harnessing AI-driven automation for UiPath testing initiatives. By attending this webinar, testers, and automation professionals can gain valuable insights into harnessing the power of AI to optimize their test automation workflows within the UiPath ecosystem, ultimately driving efficiency and quality in software development processes.
What will you get from this session?
1. Insights into integrating generative AI.
2. Understanding how this integration enhances test automation within the UiPath platform
3. Practical demonstrations
4. Exploration of real-world use cases illustrating the benefits of AI-driven test automation for UiPath
Topics covered:
What is generative AI
Test Automation with generative AI and Open AI.
UiPath integration with generative AI
Speaker:
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
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4. PULSED ELECTRIC FIELD
Pulse:
A pulse is a single disturbance that moves through a
medium from one point to the next point.
A disturbance is in some identifiable medium.
Energy is transmitted from place to place, but the
medium does not travel between two places.
5. What is pulsed electric
field?
Pulsed electric field (PEF) used short electric pulses to
preserve the food.
Pulsed electric field (PEF) treatment is an innovative
and promising method for non-thermal processing of
foodstuff.
It is suitable for preserving liquid and semi-liquid foods
removing micro-organisms and producing functional
constituents. Examples:-milk, fruit juices, soup, egg
etc.
PEF treatment is conducted at Ambient temperature ,
sub ambient temperature and slightly ambient
temperature.
6. Provide consumer microbiological safe and minimally
processed foods.
Physical properties of food is maintained.
Energy lose due to heating of food is minimized.
For food quality attributes, PEF technology is consider
superior to any traditional methods of food processing.
Suitable for heat sensitive food items.
PEF also called mild Preservation Technique
7. PEF processing has been studied
across a wide range of liquid
foods which includes-
Apple juice and sauce
Orange juice
Yogurt
Milk
Tomato juice
Carrot juice
Pea soup
Liquid whole egg and liquid egg products
9. Fundamentals of PEF
PEF : Generation of very high intensity
electric pulses (up to 15kV), for a very short
duration of time (μs)to inactivate
microorganisms
11. The principle of this process is that the product is placed
between the two sets of electrodes and then delivered
electric current to food.
The processing time = the no. of pulse*effective pulse
duration
Food is capable of transferring electricity because of the
presence of several ions. So, when an electrical field is
applied, electrical current flows into the liquid food and is
transferred to each point in the liquid because of the
charged molecules present.
The food product experiences a force per unit charge, the
so-called electric field, which is responsible for the
dielectric cell membrane breakdown in MOs & interaction
with the charged molecules of food
This may cause temporary or permanent permeabilization of
cell membranes enables inactivation of vegetative cells of
bacteria and yeasts in various foods
12.
13. The electric field may be applied in the form of –
• Exponentially decaying,
• square wave,
• bipolar, or
• oscillatory pulses
Processing temperature can be –
• at ambient,
• sub-ambient,
• slightly above-ambient temperature.
15. The plasma membranes of cells become
permeable to small molecules after being exposed
to an electric field; permeation then causes
swelling and the eventual rupture of the cell
membrane.
17. How does PEF work to
inactivate microorganism
PEF technology is based on a pulsing power delivered to the
product placed between electrodes by high voltage pulses in
the order of 5-50 kV (usually for a couple of microseconds).
The equipment consists of a high voltage pulse generator and
a treatment chamber with a suitable fluid handling system
and necessary monitoring and controlling devices.
Food product is placed in the treatment chamber, either in a
static or continuous design, where two electrodes are
connected together with a nonconductive material to avoid
electrical flow from one to the other
Generated high voltage electrical pulses are applied to the
electrodes, which then conduct the high intensity electrical
pulse to the product placed between the two electrodes.
18. The food product experiences a force per unit charge,
the so-called electric field, which is responsible for the
irreversible cell membrane breakdown in
microorganisms
This leads to dielectric breakdown of the microbial cell
membranes and to interaction with the charged
molecules of food.
Hence, PEF technology has been suggested for the
pasteurization of foods such as juices, milk, yogurt,
soups, and liquid eggs.
21. Electro-permeabilization and cell disintegration, plays a
major role in food processing operations.
Due to high intensity treatment, inactivation of
microbes can be achieved.
Juice Processing
PEF treatment of microalgae, PFE treatment of
seaweed, and other aquatic species
Plant Oil Extraction
Meat & Fish Treatment
On microbial decontamination
Sugar Processing
22. PEF in Plant Oil Extraction
In fermentation and extraction of olives. PEF treatment
can be applied to raw olives at ambient temperature ,
leading to softening of the olive tissues. Also, PEF is
used for extraction of Maize germ oil and cotton seed
oil.
The advantages of olive tissue softening are: easier
olive fermentation and cold extraction of oil.
Advantages of PEF in Plant Oil Extraction are:
1) Increased oil extraction yield.
2) Higher process efficiency.
3) Improved oil quality.
23. PEF in Sugar Processing
Benefits of PEF in Sugar Processing are:
1) Reduction of cutting force.
2) Higher extraction and refining yields.
3) Enhanced juice and sugar parity.
4) Continuous process and rapid technique.
5) Low energy requirement.
6) Enhanced product handling by tissue softening.
∙ In Sugar Processing using PEF, the pulse generator is
combined with a robust and hygienic transport system
and a PEF treatment chamber.
24. PEF in Juice Processing
PEF treated juices are more closer to fresh juices based
on quality factors.
Therefore, a clear conclusion drawn is that PEF has the
potential to become a suitable replacement to
conventional process if improvements in design are
applied.
25. PEF in Microbial
Decontamination
The characteristics of the microbes to be inactivated
can impact the effectiveness of the PEF process.
Several recent studies have been carried out on the
inactivation of pathogenic bacteria (such as E.coli and
Salmonella Enteritidis) inoculated in milk, egg and juice
products using PEF treatment, with the treated
products shown to be safe.
This emerging technique can be used as integral part of
non-thermal pasteurization, or can be used in
combination with a hurdle method, depending upon the
characteristics of liquid food product.
27. No effect on enzymes and spores
Difficult to use with conductive materials
Only suitable for liquids or particles in liquids
Only effective in combination with heat
Products of electrolysis may adversely affect foods
Safety concerns in local processing environment
Energy efficiency not yet certain
May be problems with scaling-up process
29. Pulsed Electric Field(PEF) processing of sugar beets for
sucrose extraction involves the application of
microsecond high voltage pulses in the order of 10 to 60
kV.
PEF causes tiny pore4s in the sugar beet cell walls , also
known as cell permeabilization, which facilitates sugar
leaching.
30. By permeabilizing cell membranes of sugar beets, PEF
enables tissue softening and enhanced mass transport,
resulting in improved extraction of sucrose from sugar
beets, higher product quality and purity and increased
process capacity.
31. Sugar beet processing becomes more homogenous with
PEF processing,evening the structure and resulting in
the reduction of seasonal variation in raw materials.As a
result, an improved refining efficiency and a significant
reduction of energy input and water use can be
measured.
32. The new range of industrial scale equipment- named
conditioner- has treatment capacities from 1 ton an
hour to 50 tons an hour (about 110,00 lb/h) for sugar
beet processing systems.
The pulse generator is combined with robust and
hygenic transport system and PEF chamber.
33. Input requirement of pef
Microbial inactivation: 15-40kv/cm
Sludge disintegration: 10-20kv/cm
Improvement of mass transfer in plant/animal cell: 0.7-
3.0kv/cm
35. What is a PEF treatment
chamber ?
A PEF treatment chamber consists of
at least two electrodes and insulation
that forms a volume, i.e., PEF
treatment zone, where the foods
receive pulses.
The electrodes are made of inert
materials, such as titanium
36. System components of High
Intensity PEF Processing System
The test apparatus in the continuous system consists of
different major components that are follows:
1. High voltage power supply.
2. Energy storage capacitor.
3. A treatment chamber.
4. A pump to conduct the food through the treatment
chamber.
5. A cooling device.
6. Temperature measurement devices.
7. A computer to control the operation.
37. Continue…
Energy from the power source is stored in the capacitor and is
discharged through the treatment chamber to generate an
electric field in the food material.
The maximum voltage across the capacitor is equal to the
voltage across the generator .
The bank of capacitors is charged by a direct current power
source obtained from amplified and rectified regular alternative
current main source.
An electrical switch is used to discharge energy
(instantaneously in millionth of a second) stored in the
capacitor storage bank across the food held in the treatment
chamber.
38. Continue…
A pump is used to convey the food through the treatment
chamber.
A chamber cooling system may be used to diminish the ohmic
heating effect and control food temperature during treatment.
High-voltage and high-current probes are used to measure the
voltage and current delivered to the chamber.
40. A PEF system for food processing in general consists of
three basic components :
- a high voltage pulse generator,
- a treatment chamber and
- a control system for monitoring
the process parameters .
41.
42. Power supply
The voltage increases by a transformer from line 220V
to high voltage 1000 to 5000V.
It is rectified and stored in DC form in a capacitor by
the diode.
Capacitor voltage is transformed to narrow pulses by
triggering signal and using the switch.
the high voltage power supply is used to charge the
capacitor bank and store the energy to the capacitor
bank.
43. High-power capacitors
Capacitance is the measure of the AMOUNT OF CHARGE DIFFERENTIAL
which builds up ACROSS a material when subjected to a voltage
differential.
q = DV x C or DV = q / C
I.e. Larger capacitance ----> Larger charge stored
The energy stored in capacitors is used to generate electric or
magnetic fields.
Electric fields are used to accelerate charged particles, leading to
thermal, chemical, mechanical, electromagnetic wave, or
breakdown effects.
44.
45. Transformer: Necessary output voltage is 1 we need a
transformer so that it can change line power 220V to
output selective voltage between 1-5 kV. Switching Power
supply supply has been used so that changing its frequency
tends to various voltages in the output
Capacitor: The minimum desired load resistance is 150 ohm
Necessary maximum pulse width is 100µs; i.e. in the worst
situation, in interval of 100µs, the current of 33A must be
loaded. Assumed capacitor will be discharged after each
pulsing.
Capacitors number: 32 So each four capacitors are series
together and package. All eight packages are fastened
parallel. Finally the capacitor bank resin insulated and
constructed with dimension 13*13*15cm. Diode: The diode
rectifies ac output of transformer in the form of semi-wave
and charges the capacitor. It should tolerate the current
that charges the capacitor.
46. Switches
The discharging switch also plays a critical role in the
efficiency of the PEF system.
In increasing order of service life, suitable switches for
PEF systems include: ignitrons, spark gaps, trigatrons,
thyratrons, and semiconductors.
Solid-state semiconductor switches are considered by
the experts as the future of high power switching
(Bartos, 2000).
High-power switching systems are the connecting
elements between the storage device and the load.
47. Continue…
There are two main groups of switches currently
available: ON switches and ON/OFF switches.
ON switches provide full discharging of the capacitor
but can only be turned off when discharging is
completed.
ON switches can handle high voltages with relatively
lower cost compared to ON/OFF switches.
however, the short life and low repetition rate are
some disadvantages to be considered for selection.
The Ignitron, Gas Spark Gap, Trigatron, and Thyratron
are some of the examples from this group.
48. continue…
ON/OFF type switches have been developed in recent
years that provide control over the pulse generation
process with partial or complete discharge of the
capacitors.
Improvements on switches, mainly on semiconductor
solid-states witches, have resulted in longer life spans
and better performance.
The gate turn off (GTO) thyristor, the insulated gate
bipolar transistor (IGBT), and the symmetrical gate
commutated thyristor (SGCT) are some examples from
this group
49.
50. High voltage pulse generator
The high voltage pulse generator provides electrical pulses of the
desired voltage, shape and duration by using a more or less
complex pulse forming network (PFN).
PFN is an electrical circuit consisting of several components:
- one or more DC power supplies,
- a charging resistor,
- a capacitor bank formed by two or
more units connected in parallel,
- one or more switches, and
- pulse-shaping inductors and resistors.
- The DC power supply charges
the capacitors bank to the desired voltage.
51. Using this device, the ac power from the utility line (50-
60Hz) is converted in high voltage alternating current
(A) power and then rectified to high voltage dc power.
52.
53. Pump & Piping Used in PEF
To Bring liquid or semi liquid product from raw product
tank to treated product tank.
Postive Displacement pumps or peristaltic pumps are
commonly used.
Continuous or pulseless pumps are preferred to ensure
treatment homogeneity.
Stainless steel piping is preferred for sanitary reason.
No restriction exist for the use of other types of pumps.
54. Control And Monitoring
Devices
PEF System are usually hooked up to a central computer
that control the operation of
- high voltage pulse generator
- voltage and pulsing frequency
- operation of pumps and
electric valves
Computer also records data logs which includes
temperature at several points, flow rate of product,
voltage, currents and power curves applied pulses.
Commercially available sofwares that can be used in PC
to administer the control and data gathering process-
HP V Lab® or Lab view®.
56. PEF Treatment chamber :
The basic idea of the treatment chamber is to keep the
treated product inside during pulsing, although the
uniformity of the process is highly dependent on the
characteristic design of the treatment chamber.
A treatment chamber usually consists of two electrodes
held in position by an insulating material which also
forms an enclosure containing the sample to be
processed.
57. For proper designing of chamber the electrical
properties of slurries have to be treated and fluid
dynamic aspects related to the flow of viscous material
are to be considered.
Treatment chamber must guarantee the homogenous
and continuous Pulse Electric Field (PEF) treatment of
food material.
Several different treatment chambers have been
proposed. Example: parallel plate, concentric cylinder,
and co-field.
58. These chambers have been designed for inactivation
purposes of treating almost all liquid foodstuff and thus
homogenous material. In such cases, the presence of
solid particles in food material has been considered in
determining the chamber configuration.
The principal requirement to the guaranteed in
designing a treatment chamber is the homogeneity of
the generated electric field.
Homogeneity of the electric field exists throughout the
gap between the electrodes, in fact, it ensures
homogenous treatments.
59. The design of the treatment chamber is an important
parameter for microbial inactivation and must conform to
several specifications:
The treatment chamber should resist high current intensity.
The distribution of electric field in the treatment chamber
should be as uniform as possible.
`Dead zones' (absence of electric field or of sample
circulation) should be avoided.
Dielectric breakdown (arcing) should be avoided since it
would induce nonuniform processing and local overheating
of the sample. It can be induced by local field
enhancement on an electrode, electric tracking along an
insulator surface and/or the presence of gas bubbles in
samples.
The materials used should minimise electrochemical
phenomena at the electrodes.
60. PEF Treatment Chamber
Design:
Treatment chambers are mainly grouped together to
operate in either a batch or continuous manner; batch
systems are generally found in early designs for handling
of static volumes of solid or semi-solid foods.
61.
62. Batch Systems:
They are majorly of two types:
1) Parallel plate electrode chamber:
This consists of two electrodes supported on brass
blocks placed in a U-shape polystyrene spacer.
Different spacers regulate the electrode area and
amount of food to be treated.
This chamber could support a maximum electric field of
30kV/cm.
63. 2) Glass coil static
chambers:
This model uses a glass coil surrounding the anode.
The volume of chamber is 20 cubic cm.
The liquid media used is NaCl solution, with σ= 0.8 to
1.3 S/m, because there is no inactivation with a non
conductive medium.
64. Continuous flow systems:
Continuous flow PEF treatment chambers are suitable
for large scale operations and are more efficient than
static chambers.
There are majorly four types of continuous flow systems:
Parallel plate chamber
Co-field flow chamber
Coaxial continuous PEF chamber
Enhanced electric field continuous treatment chamber
67. 1. Parallel plate chamber:
They were first designed to treat a confined, static volume.
This design incorporates parallel plate geometry using flat electrodes
separated by an insulated spacer.
Due to the electric field strength limitation it is difficult to increase
product load and this made this chamber more efficient.
The major disadvantage of this type of design is the low productivity of
these cambers.
68. The parallel plate treatment chamber consists of two stainless steel
plate electrodes and a Teflon insulator.
The insulator is cylindrical and presents internal square cross section
cavities in which the two electrodes are placed.
Two side holes allows the electrical connection of the electrodes with
the pulser. The chamber consists of two symmetric halves, easily
opened for cleaning.
69. 2. Co-field flow chamber:
These chambers have two hollow cylindrical electrodes
separated by an insulator to form a tube through which the
product flows.
Field distribution in co-field flow chamber is not expected to
be uniform, though some useful advantages may be gained by
special shaping of the insulator.
The primary advantage of ci-field chamber is that they can be
designed to operate in PEF systems at lower currents than
coaxial chambers.
70.
71. 3. Coaxial continuous PEF chamber:
They are generally composed of an inner cylinder surrounded
by an outer annular cylindrical electrode that allows food to
flow between them.
A protruded outer electrode surface enhances the electric
field within the treatment zones and reduces the field
intensity in the remaining portion of the chamber.
Using the optimized electrode shape, the prescribed field
distribution along the fluid path without an electric field
enhancement point was determined.
This chamber can be used in inactivation of pathogenic and
non-pathogenic bacteria, molds, yeasts and enzymes present
in liquid foods.
72.
73. 4. Enhanced electric field
continuous treatment chamber:
In this we apply the concept of enhanced electric fields
in the treatment zones by development of continuous
co-field flow PEF chamber with conical insulator shapes
to eliminate gas deposits within the treatment volume.
The conical regions were designed so that the voltage
across the treatment one could be almost equal to the
supplied voltage.
74.
75. Reference
Mirzaee, H., & Pourzaki, A. (2011). Designing and
Manufacturing High Voltage Pulse Generator with
Adjustable Pulse and Monitoring Current and
Voltage: Food Processing Application. World
Academy of Science, Engineering and Technology,
International Journal of Electrical, Computer,
Energetic, Electronic and Communication
Engineering, 5(12), 1910-1915.
Mohamed, M. E., & Eissa, A. H. A. (2012). Pulsed
electric fields for food processing technology.
In Structure and function of food engineering.
InTech.
76. Handbook of Food Science, Technology,
and Engineering
Novel Food Processing Technologies
De Vito, F. (2006). Application of pulsed electric field
(PEF) techniques in food processing. Rozprawa
Doktorska, UNIVERSITÀ DEGLI STUDI DI SALERNO.