FAQ about Pulsed Electric Field Processing

What is pulsed Electric Field Processing?

Pulsed Electric Field (PEF) processing is a non-thermal food processing method that utilizes short, high-voltage pulses. These pulses facilitate poration in plant, animal, and microbial cells, which leads to cell disintegration and microbial inactivation. PEF is instantaneous, precise, adaptable, and energy-efficient. As it minimizes heat, the processed products retain better nutritional values and have an extended shelf life compared to those processed through traditional methods.
PEF enhances the extraction rates of juices, sugars, colorants, and other active compounds, and it significantly prolongs the shelf life of products. It accelerates diffusion processes such as the removal of water from plant or animal tissues and the absorption of marinades, spices, and auxiliary substances. This acceleration results in valuable time savings during production processes.Electroporation of plant and animal raw materials enhances mass transport processes such as extraction, drying, freezing and pressing, saving time and money and increasing value.

Is PEF Processing the Same as Electroporation?

Yes, it is. PEF processing and electroporation both refer to the same technique. The pulsed electric field induces poration of cell membranes, which is the origin of the term ‘electroporation.’ ‘Permeabilization’ is another term used in this context.PEF treatment damages cell membranes and inactivates micro-organisms.

What is the Aim of PEF Processing or Electroporation?

The primary goal is to add value by maximizing the effectiveness of natural raw materials. Electroporation leads to significant enhancements in yield, freshness, and flavor across a diverse array of foods and applications.Electroporation of plant and animal raw materials enhances mass transport processes such as extraction, drying, freezing and pressing, saving time and money and increasing value.

How Does PEF Work?

PEF processing involves applying microsecond high-voltage pulses ranging from 10 to 60 kV. These high-voltage pulses create pores in cell membranes, leading to a loss of their barrier function, leakage of intracellular contents, and a decrease in vitality. The treatment is continuously applied in a chamber, which consists of multiple electrodes. As the products—liquids, semi-viscous liquids, or solids—are pumped or transported through the treatment chamber, they are exposed to these high-voltage pulses. The required treatment duration is less than a second. The pulses are administered at repetition rates of up to 1,000 per second to ensure adequate treatment of all volume elements. In addition to electrical parameters like field strength and specific energy input, factors such as product temperature and recipe also influence the treatment intensity.PEF treatment leaves vitamins, antioxidants, colorants, proteins, fatty acids and polysaccharids unaffected

What Types of Foods Can Be Treated?

Depending on the application’s objective, solid, semi-liquid, and liquid foods can be treated. When the goal is cell disintegration in plant or animal tissue, there are practically no size limitations.
This technique can be applied to whole fruits, vegetables, potato tubers, as well as to pieces of fruits or vegetables and their mashes, prior to separation processes. However, the maximum size of the plant or animal tissue must be smaller than the gap in the treatment chamber.
For achieving microbial inactivation, a higher treatment intensity is required. This limits its applicability to pumpable products with a particle diameter of less than 20 mm.Applications of PEF processing are microbial inactivation in beverages and liquid foods, and cel disintegration of solid raw materials such as potatoes, fruits, vegetables, meat and fish for improved mass transport processes and product quality.

Can PEF Processing Be Applied to Products Containing Air Bubbles?

The dielectric strength of the food matrix significantly influences the applicability of PEF processing, as it is essential to prevent dielectric breakdown. Air bubbles cannot withstand high electric field strengths. They might be present in sparkling products or released due to an increase in temperature. Particularly for microbial inactivation, which requires a higher electric field strength, it is necessary to remove air from the product. Techniques like vacuum degassing or applying positive back pressure to pressurize the treatment media during PEF processing can help minimize the presence of air bubbles.
The dielectric strength of the food matrix has a significant influence on the applicability of pulsed electric field technology

What are Typical Applications of PEF Processing?

PEF processing has a variety of applications, including the mild preservation of beverages and semi-liquid food products. It is used in treating potatoes to replace thermal preheating and in various extraction processes. These processes include extracting antioxidants, oils, and proteins from algae, sugar from sugar beets, and nutrients or fibers from peels and stems. Additionally, PEF processing can be applied to reduce acrylamide levels, concentrate protein from potatoes, and enhance the production processes of cooked ham and dry sausage.PEF treatment leaves vitamins, antioxidants, colorants, proteins, fatty acids and polysaccharids unaffected

What are the Benefits of PEF Application?

Pulsed Electric Field (PEF) processing offers numerous benefits, including time and cost savings, and enhancing product quality. It accelerates slow mass transport processes, such as during the drying of plant or animal tissue, thereby reducing processing times. Juice and oil extraction yields are increased through its use. Another advantage is the reduction of tumbling times in meat processing due to improved brining processes. In dry sausage production, PEF technology enhances the drying process, thus shortening the required drying time.
 
When applied for food preservation, PEF produces high-quality, fresh-like liquid foods and beverages with high nutritional and functional value. Unlike thermal pasteurization, PEF does not negatively impact vitamins, proteins, and other valuable nutritional and functional components. This makes it advantageous for heat-sensitive liquid foods where thermal pasteurization is not suitable.
PEF enables the generation and precise measurement of significant increases in yield, freshness, and flavor preservation across a broad range of food types. It brings positive and substantial changes to manufacturing by improving output, reducing labor costs, streamlining supply chain logistics, and reducing retail waste.
PEF processing for mild preservation of beverages and liquid foods

What are the Benefits of Replacing Thermal Preheating in Potato Processing with PEF Treatment?

Replacing traditional preheaters with PEF systems in potato processing offers several advantages. PEF treatment enhances cut quality and significantly reduces breakage in French fries. It also leads to reductions in water and energy consumption. Additionally, blanching, drying, and pre-frying times are shortened. The treatment also improves the leaching of sugars. Furthermore, PEF can reduce the absorption of frying oil and the fat content in potatoes by up to 50%.PEF treated and fried potato products contain less oil. The treatment can reduce frying oil absorption and fat content up to 50%.

Which Other Ingredients Does Electroporation Affect?

Electroporation primarily impacts cell membranes with targeted effects. It can inactivate various kinds of vegetative spoilage and pathogenic microorganisms. However, its effect on enzymes, spores, and viruses is limited. Other constituents like vitamins, minerals, pigments, and flavors are retained. Unlike heat treatment, the functionality and nutritional value of proteins are hardly affected by electroporation.
PEF treatment leaves vitamins, antioxidants, colorants, proteins, fatty acids and polysaccharids unaffected

Is Food Sterilization Also Possible with PEF Technology?

PEF technology’s use in food preservation extends beyond mild pasteurization. Food sterilization is achievable with PEF, especially when combined with higher temperatures, to effectively eliminate spores.
PEF treatment allows cold pasteurization of liquid foods, such as baby food

Is the Shelf Life of PEF-Treated Foods Comparable with Thermally Pasteurized Foods?

Generally, the shelf life of PEF-treated foods is comparable to that of thermally pasteurized foods. Similar to thermally pasteurized products, PEF-treated foods are typically stored under refrigeration.In general, the shelf life of both PEF-treated and thermally pasteurized foods is comparable. Like thermally pasteurized foods PEF-treated products are usually stored refrigerated.

Is Commercial Scale Equipment Available?

Yes, Pulsemaster has developed industrial-scale equipment, named the Conditioner, with treatment capacities of up to 5,000 liters per hour (1320 US gallons per hour) for microbial inactivation, and up to 50,000 kilograms per hour (110,000 pounds per hour) for cell disintegration. Well-proven pulse generators and treatment chambers are available. This equipment is industry-ready and complies with all safety regulations.
Pulsemaster has also developed PEF systems for the science sector. The company manufactures a range of PEF systems specifically for science and research organizations, tailored to meet particular research needs. These tailor-made pulsed electric field systems are designed to be compact and modular, facilitating easy integration and power upgrades. The science systems are user-friendly and easy to service and maintain, thanks to their modular design featuring field-replaceable units.
PEF Machine by Pulsemaster

Can PEF Systems Be Implemented in Existing Processing Lines?

Yes, as a continuous, short-time process with low space requirements, pulsed electric field (PEF) processing can easily be integrated into existing lines. For applications involving cell disintegration, a typical processing line consists of a treatment tank unit and a pulse generator unit. In the case of mild preservation of fruit juices, a standard processing line includes a supply tank, a fluid pump, a pulse generator unit, a cooler (if required), and a buffer tank. The processing line can be cleaned using Clean In Place (CIP) or Steam In Place (SIP) methods.PEF treatment damages cell membranes and inactivates micro-organisms.

What Are the Costs of PEF Technology?

PEF is a low-energy process. Depending on the application type, the specific energy consumption ranges from 10 to 100 kJ/l (2.6-26.4 kJ/US gal.) of product. The smaller the target cells, the higher the required treatment intensity. On a commercial scale, the total costs are expected to be around 1 Euro per ton (approximately 0.1 Eurocent per liter or kg) for the treatment of plant cells and 10 Euros per ton (approximately 1 Eurocent per liter or kg) for microbial inactivation.
In US Dollars, the total costs on a commercial scale are expected to be approximately 0.056 US Dollarcent per pound for cell disintegration and 4.92 US Dollarcent per gallon for microbial inactivation.
Results of PEF processing are enhanced drying, extraction and pressing, fresher food products with a higner nutritional value and longer shelf life, and the saving of time, energy and water.

Where Can Electroporation Be Tested?

Pulsemaster provides customers with access to lab-sized PEF systems and other laboratory facilities for testing purposes, product and process development, and challenge tests. They offer confidential product evaluations, as well as validation of food safety and shelf life.Pulsemaster supports innovation and manufactures a range of PEF systems for science and research organizations, tailored to suit specific research need

Do You Have Examples and Cases of PEF Implementation and of PEF Treated Foods and Beverages Placed on the Market?

Providing specific examples and cases of PEF implementation and market-placed PEF treated foods and beverages is challenging due to confidentiality issues. However, the commercial adoption of PEF systems is expanding globally. To date, several PEF-treated juices are available in markets worldwide. Particularly in potato processing, there is a growing interest in PEF technology as an efficient alternative to traditional preheaters. Potato applications using PEF are already operational in the US and Canada. Additionally, a juice pasteurization application in the US has been utilizing PEF for several years. There are also commercial PEF food applications in various countries across Europe, as well as in Australia, India, and China.
Pulsemaster’s highly skilled engineering experts, with deep knowledge and industry experience, have designed and built over 70 PEF systems since 2009. These systems cater to a broad spectrum of applications and outputs in the global food industry. The applied pulse generators have a proven track record in the food industry and PEF research applications.
All PEF systems used in the industry for producing French fries and crisps, built according to the Marx solid-state typology and successfully running in the potato industry in Germany, the US, Canada, the Netherlands, Belgium, Austria, Australia, India, and China, technically originate from the work of Pulsemaster’s highly qualified team of German engineering experts.
Each Pulsemaster PEF system is constructed with the highest quality German and Dutch engineering, ensuring the capability to withstand continuous operation (24/7) in the industry.
Pulsemaster combines years of unique experience with pulsed power technology

Is Food Treated by Electroporation Considered a Novel Food?

Under the Novel Food Legislation, which applies to food products and ingredients in specific categories marketed within the European Union (Regulation EG 258/97), new production processes for foods must be evaluated. To be classified as non-novel foods, they should not induce any significant changes in the composition or structure of the foods or food ingredients that could affect their nutritional value, human metabolism, or the level of undesirable substances. So far, PEF treatment has not been shown to cause significant changes in the composition or structure that would impact nutritional value, metabolism, or the level of undesired substances. Therefore, it can be assumed that PEF-treated fruit juices are not considered novel foods.PEF systems for science and research

For further information contact:

Pulsemaster BV
pulsemaster.us
e-mail: info@pulsemaster.us
tel. +31 497 820300