The pros and cons of various pasteurization methods

Multiple outbreaks of E coli and Salmonella the last 15 years raised concerns about the safety of fresh fruit and vegetable juices and the latest generation of cold pressed juices. This created the urge to develop better pasteurization methods and equipment in order to save the juice industry and particular consumers. In the beginning there was simply thermal/heat pasteurization, but within the last decade there has been a vast number of pasteurization methods developed.

Every new method is an attempt to find a better way of pasteurizing. Better, in terms of pasteurization, usually means to further extend shelf life and preserve taste, look, and other sensory aspects, while effectively killing harmful bacteria and pathogens. This article gives a brief overview of the current pasteurization methods and technologies.

Method Thermal / non-thermal Time Notes
Low Temperature Long Time Pasteurization (LTLT) Thermal: 60°C – 70°C 30 – 60 minutes Classic method with a lot of undesirable quality changes during the process.
High Temperature Short Time (HTST) Thermal: 70°C – 90°C 1 minute Widely used nowadays, but due to heating nutritional value, taste and color breaks down.
High Pressure Processing (HPP) Non-thermal Ca. 2-5 minutes Through the use of extremely high pressures (500-600 MPa) for usually about 2-5 minutes, the microbes are “crushed” to death.
Pulsed Electric Field (PEF) Non-thermal < 5 seconds PEF uses lower temperatures than thermal pasteurization, in combination with a pulsed high voltage (25,000 Volts) across a gap through which the juice flows. This allows for lower temperatures than thermal pasteurization. PEF 2.0 is even a non-thermal treatment.
PurePulse (PEF 2.0) Non-thermal < 2 seconds Laminar flow treatment resulting in a much lower peak temperature treatment compared to a normal PEF treatment.
Ultraviolet Light (UV) Non-thermal < 5 seconds A cheaper method than thermal for producers, whom could simply not afford a thermal pasteurizer. UV is a method for the lab, and not for industrial processes. UV inactivates vitamins and not sufficient microbial inactivation is obtained.
Membrane Filtration (Ultrafiltration and Microfiltration) Non-thermal < 5 seconds Traditionally these methods are used for filtration, and are able to actually filter out microbes as well. The effectiveness depends on many factors and is generally more applicable for more processed juices that are filtered anyway, like clear apple juice, hard cider, or beer. Since these methods cause color changes and some flavor changes, they are not widely used for natural juices that contain a cloud.

As you can see, there are many non-thermal pasteurization techniques that can be an alternative for the classic thermal pasteurization methods. The most serious alternatives for commercial juices and smoothies producers are HPP and Pure Pulse (PEF 2.0). The advantages of no loss of nutritional value, taste and flavor are nowadays for consumers of big importance. More information about these techniques you can find on the TOPwiki, which is developed by partner TOP.

The first cold press technology that meets European hygiene standards

The Dutch companies JFPT/foodlife and Cool Wave Processing have joined forces and developed a new cold press technology. “The Cold Press No. 1” fully complies with the latest European legislation for hygiene (EHEDG) and safety (CE). With cold pressing both nutrients and flavour of fresh fruit and vegetables juice will remain best preserved.

In the United States, the cold press technology has been used for decades and has become the standard in juice production. The demand for healthy, fresh and natural juices is also on the rise in Europe, and therefore the demand for cold pressing too. JFPT/foodlife and Cool Wave Processing have designed the new press to exactly meet the European standards.

The Cold Press No. 1 is built mainly from stainless steel, even the electrical cabinet that is normally made of plastic. It has round pipes instead of pipes with straight angles and all the plastics are blue instead of white. This makes it the first cold press that completely complies with the strict EHEDGE guidelines. Current presses demand for high maintenance and are difficult to clean; these two aspects are especially taken into account in the design of the new press.

Combined with the mild preservation technology PurePulse from Cool Wave Processing, the two companies offer a complete package for producers of fresh fruit and vegetable juice. Interested producers can discover the new press in the test center of JFPT/foodlife in Zwolle. The first series of The Cold Press No. 1, with a capacity of 100 liters per hour, will be delivered in December. From the beginning of January the next 10 presses are available. Cold presses with larger capacities will be available in the course of 2015.

Contact for more information.

Coldpressing facility for fruit and vegetable juices in The Netherlands

Producers of fruit and vegetable juices that are interested in producing fresh, cold pressed juices, but want to test first, can come to the cold press pilot facility at TOP bv in Wageningen. Here, producers can perform tests to find out which pressing method is most suitable for their juices. The demand for healthy juices is increasing and coldpressing is the best way to preserve the healthy nutrients in fresh juices.

The cold presses of TOP b.v. are of course also part of this pilot facility. CoolWave Processing has made arrangements with TOP to make different industrial pressing techniques available. For example, producers can test with the small CP01press that has got the same effect as our largest press, the CP20. The unique thing about the pilot facility is that the pressed juices can directly be treated with the mild pasteurization method PurePulse. This makes the juice safe because harmful bacteria are killed, but without loosing the healthy nutrients. It also gives the juice a couple of weeks shelf life, without loss of flavor.

We are proud to be able to help producers make the best decision with regards to their equipment. As a juice producer starting with cold pressing, it can be very hard to decide what equipment to buy as the ideal press technique may differ for each product. For example a screw press is best for leafy vegetables, while a hydraulic press is best for fruit and vegetables with lots of flesh. We invite you to come over to Wageningen and find out yourself what solution suits your products best.

Read more about the press principle of our ColdPress juice extraction equipment.

Did you know there is loads of (free) information on PEF 2.0?

During the development of PEF 2.0 we have collected a lot of information on the technology. And we still are. This helps us in making the story on the technology stronger, and convince future users of the potential of the technology. In order to help you with the orientation on the technology and its benefits, we have launched different platforms where we share the information we have.

On our Slideshare you can find various reports on consumers perception, FDA requirements, the effect of pH and temperature during PEF treatment on micro organisms, quality changes in PEF treated juices during storage and so on.

On our Pinterest board we share a lot of inspirational content, such as pictures of products that are treated with PurePulse, movies and presentations about the technology and its applications.

The wiki page of PurePulse provides extended information about the possible applications of PurePulse on food products. Here you can learn everything about how it works, what the parameters are, the benefits of course and the costs.

If you have a question on which you cannot find the answer on these pages, or you just want to have a conversation about PurePulse and your production process, do not hesitate to contact us. We are here to help you.

Read more about the second generation Pulsed Electric Field, PurePulse.

PurePulse pilot line available for risk analysis

The preservation method Pulsed Electric Field (PEF) is officially approved by de U.S. Food and Drug Administration (FDA). Research indicates that inactivation of relevant pathogens is possible, which is an important requirement of the FDA. PurePulse, the new generation of PEF, is hereby recognized as a base technology that meets the rigorous standards in the USA.

A new method also brings up questions such as: will harmful pathogens be killed sufficiently and does it meet the requirements of the legislation? Because PurePulse is such a young technology it was necessary for us to built a broad experience with FDA legislation and to carry out numerous risk analyses on different kind of fruit and vegetables juices. With success, because the outcome is positive.

The legislation on food safety in America and Europe is basically the same. In both cases it is necessary to provide a risk analysis of the raw materials. In addition, the FDA requires for juice preserving methods that they are able to prove a 5-log reduction of pathogens. That means that 99,999% of the pathogens are inactivated. In case of juices and smoothies, E.coli is often the target pathogen. To prove this, studies were carried out on Pulsed Electric Field with relevant surrogate pathogens, and the results are very positive. PurePulse therefore fully meets the standard requirements of the FDA. This underlines that the method is not a ‘novel food’ technology, which means that there are no obstacles in the EU to apply PurePulse in food production.

At Cool Wave Processing in Wageningen, we have a pilot line available for producers that want to do a risk analysis of their raw materials with surrogate pathogens. This line is also available for sensory testing and more extensive test programs.

Market of raw juices continues to growth

The rise of health juices that help to reset or detox the body is enormous. More and more new and existing juice producers choose to produce healthy, raw juices. The method of extraction is crucial. This is evident since the sales of our ColdPress presses are on a rise. The presses seem to be popular with small-scale producers, who focus on healthy and honest products. That is why we offer both large presses for large-scale production as very compact and easy to operate machines, such as the CP01. The young Dutch company Greenz Love makes healthy juices based on fruit and vegetables. The company emphasizes on the extraction technology cold pressing, because that makes it so healthy. There is no heat involved with cold pressing. The result is a pure juice: it does contain all the goodness of the fruit and / or vegetables, but no unwanted components that cause taste abnormalities and accelerated oxidation. Therefore Greenz Love selected the CP01 juice press of ColdPresses. Menno Bernard, managing director Greenz Love: ‘our goal is to conquer the Netherlands and then the rest of Europe with our healthy and delicious juices. With the compact and flexible CP01 we can quickly respond to the needs of our consumer, which is essential in this rapidly emerging market.’

Read more about the press principle of our ColdPresses coldpressing equipment.

Raw milk food safe with PurePulse

There is an increasing interest in raw milk because of health benefits and the intense and full flavour. Currently, the PurePulse technology is used for treating fresh juices. But at Cool Wave Processing we are also very interested in the possibilities with raw milk. Treating raw milk with PurePulse ensures that all harmful organisms that are naturally found in raw milk, will be disabled. Moreover, the original flavour and nutrients are substantially retained. This is a breakthrough as it offers the opportunity to make fresh raw milk available on a larger scale and in a safe way, as this is a major issue. Research into the optimal process parameters for treating raw milk is still on going. However, CWP is already looking at the potential market and consumer acceptance of raw milk treated with PurePulse and the legal framework. Currently we are working together with other parties on a consortium to market raw milk. The plan is that in 2015 the first products will be available on the market.

Read more about the second generation Pulsed Electric Field PurePulse

PurePulse, the profitable alternative for HPP

Juices are classically treated with heat. The process called pasteurization – treatment between 80-100 °C – is more than 150 years old. Since 10 years two alternative treatments have emerged on the market: Pulsed Electric Field (PEF) and High Pressure Processing (HPP). Both technologies provide excellent tasty (raw) food products with extended shelf life. The results in terms of shelf life and taste are the same. But not for business. PEF is much more profitable! PurePulse, the newest generation of PEF treatment is therefore a very interesting alternative for HPP.

The PurePulse technology is a continuous flow that enables juice producers to treat high volumes at a much lower cost per liter than HPP. The multiple handling that HPP requires for these refrigerated foods is a cost disadvantage that can only be borne by high-margin products. PurePulse technology (PEF 2.0) can easily kill 5-6-log food pathogens and extend the shelf life to 4-6 weeks or more. The downside of PEF is that liquid products with particles cannot be cold pasteurized. A PEF treatment can also be done at elevated temperatures; the effect is partial spore-inactivation as well.

PurePulse finally makes it possible to apply mild preservation technique in a profitable manner, and on a large industrial relevant scale. HPP will probably remain the standard for small batches, tolling and specifically ‘solid’ food products like meat and ready-to-eat meals. But PurePulse will be the next standard in large continuous liquid food production.