Posts by Wouter de Heij

Owner of Food4Innovations. CEO of TOP b.v. Partner of BOX n.v.

Cold Press and PurePulse technology, a golden match

PurePulse technology enables juice producers to maintain the fresh quality of fruit and vegetable juice beverages. But to achieve the best results it is important the processed juice has the best quality to begin with. The Cold Press No.1 is a juice extraction machine that can extract the juice out of most fruits and vegetables with high extraction yields without negative impact on flavor, vitamins and enzymes.

Apples, roots or leafy greens; the Cold Press No.1 easily presses the juice out of it. Depending on the type of fruit or vegetable the extraction yield is 50 – 80% without using heat. The juice that is extracted is smooth, without particles and tastes as fresh as can be.

Batch size is crucial for design. Do you know your optimal batch size?

Large-scale processing of drinks and juices almost always happens through continuous processing technology.

Through heat exchangers amounts of thousands to ten thousands liters of juice, drinks or milk are pasteurized and then filled into bottles or cartons. The capacity of the industrial fillers is mostly expressed in number of packs per hour, while the capacity of the heat exchangers is expressed in liters per hour.

Between a filler and a pasteurizer (also when using a PurePulse system), often one or more sterile tanks are placed.  At the design of a complete production line some serious engineering is required. To conduct this engineering process in a successful way, the so called typical batch size is crucially important.

PurePulse makes raw milk safe

Raw milk contains bacteria that can damage your health. Through heating (pasteurizing or sterilizing) the damaging effects are impeded, but it also changes the nutritional value and taste of the milk. PurePulse makes it possible to render bacteria harmless while taste and quality of the raw milk are preserved.

PurePulse is the technology of the technology company CoolWave Processing from Wageningen. It is a modern preservation method in which a series of short electric pulses are generated. These pulses inactivate bacteria in the food. This accomplishes a shelf life comparable to heat-pasteurized products.

Safety of fresh nut milk is not obvious

Just like cow milk, nut milk isn’t sour, which means that the acidity (pH) is relatively high. When performing a correct risk analysis, you will conclude that there is a potential hazard for food safety, caused by growing spores of pathogenic bacteria present in the nut milk, which can make consumers seriously ill.

That is why sterilization is often chosen to kill the spores, still making the product safe. This gives the product without cooling an almost endless shelf life, but the taste will have deteriorated significantly.
Another option to produce safe nut milk is by adding fruit. The combination of nut milk and fruit lowers the acidity, and in addition tastes great.

Milk made of nuts

At CoolWave Processing we already have a significant amount of experience with fresh and cold pressed juices. Next to these applications we get a lot of questions about other special applications.

One that surfaces remarkably often is nut milk. This is actually not surprising, because next to tasty nuts are healthy, as stated in the advice of the Health Council in their guidelines of 2015 to consume about 15 grams of nuts daily.

Nut milk is a milky drink made of nuts, by grinding them mixed with water and then sifting them. A useful tool to produce fresh nut milk on a semi-industrial scale is a cold press (, with which you can easily press the nut milk out of the nuts and water.

PurePulse now also for vegetable juices, soups and sauces

PurePulse, the technology of the young tech-company CoolWave Processing, has had an upgrade. This makes it possible to also increase the shelf life of high conductive products like vegetable juices, soups and sauces with PurePulse, without loss of taste, color or nutritional value.

PurePulse is a modern conservation method, which generates short electric fields that kill bacteria in the food, which cause premature decay. Thus a shelf life is achieved comparable to that of heat-pasteurized products. After treatment a product can be kept for a couple of weeks when refrigerated. Because of the short pulses, the product itself is hardly heated, preserving quality, taste and color. So the products taste the same before and after the treatment.

Cold brews, nut milk, infusions: Trends in fresh cold beverages

Did you notice that there’s a lot more to choose from than standard soda or lemonade in premium supermarkets and trendy bars? A lot of new beverages have been developed in the last few years. It is noteworthy that many of these new beverages are fresh or have a cold preparation process. That makes them easy to combine with the mild preservation method PurePulse. A selection of the latest trends in the field of beverages:

Cold brews – one of the coolest drinks currently is a cold brew. Ground coffee beans or tealeaves are soaked 14 to 18 hours in cold water with a temperature of 12 to 18°C. As a result, the taste is very pure. This cool coffee and tea is sweeter, lighter and more refreshing than ‘traditional’ iced coffee or tea.

The difference between PEF and PEF 2.0 explained

When explaining the PurePulse method the term PEF 2.0 is often used. This is the improved version of PEF. But what is that difference exactly? Let us explain:

The 1st generation PEF works with a pulsed electric field at a high frequency. In this process the treated product is heated up to 60°C or even 70°C. This makes the impact on the product similar to regular pasteurization or hot fill: a long shelf life, but only very limited quality gains in terms of taste and nutrient retention. A minor benefit, and that is why this PEF method was never fully embraced by the food industry.

Cool Wave Processing has solved this problem by developing PEF 2.0. The pulse frequency used by PEF 2.0 is much lower, as a result of which the temperature of the product does not exceed 40°C to 45°C.

PurePulse now also available for small-scale production

Cool Wave Processing introduces a new, smaller-scale version of the PurePulse system: the PurePulse 350L system, with a throughput of 350 liters per hour. Because the system is smaller, the investment is also lower. This makes the technology more accessible for small-scale producers.

Wouter de Heij, director of Cool Wave Processing: “Implementing a new preservation method remains a challenge for many producers. With this entry-level model, we lower the threshold. Fresh, natural and a long shelf life will remain an important issue for the industry. By starting small and then being able to scale up, the risk for producers is limited. In addition, the PurePulse system is 3 to 4 times cheaper in investment costs compared to the entry level of the HPP technology.”

Better cold pasteurized than cooked until nothing’s left

Fresh, cold pressed juices contain naturally a lot of healthy micronutrients and enzymes. When fruit and vegetables are heath pressed or heath pasteurized most of these micronutrients and enzymes are lost. Cold pressing is a mild way of pressing that optimally preserves the taste and nutrients.

The combination with PurePulse as a mild pasteurization method is ideal, because none of the benefits of cold pressing are lost. Besides, it extends the shelf life of your cold pressed juice from a few days to a few weeks without heating or high pressure. The arrival of this technology makes heating juices for safety and shelf life reasons unnecessary.