Cranberry dehydration method promises cost, time savings

Developed by Canadian firm EnWave, the nutraREV process is said to compete with standard freeze drying technology at one sixth of the capital cost.

The Radiant Energy Vacuum (REV) process, which uses vacuum microwave technology, is targeting a number of different product categories, including dehydrated tomatoes, potatoes, onions, herbs, and some fruits. However, EnWave told NutraIngredients-USA.com that nutraREV can also be used in combination with grinding to produce cranberry and blueberry powders for use as nutraceutical ingredients.

Time and money​

“Cranberry powders are generally produced either as a freeze-dried juice extract, or by freeze drying the whole berries and grinding them. EnWave has successfully produced cranberry powder in our lab-scale nutra​REV machine as part of our testing program, and we could definitely provide an alternative, very competitive technology to these other two methods,”​ said VP of corporate development Jennifer Thompson.

As well as providing a potentially cheaper dehydration method – partly because it utilizes less energy – the technology can also process the berries much faster than freeze drying, said Thompson.

“Generally, production of freeze dried berries takes a minimum of 48 hours. In our nutraREV machine, we can dry the berries in about 40 minutes​,” she said. The dehydrated berries would then pass to the grinding stage.

In order to produce dehydrated whole blueberries, Thompson explained that an extra three hours would be necessary to allow for pre-drying on a hot-air conveyor. This reduces moisture content and produces the required ‘puffed’ appearance.

“We can dry pretty much anything which comes in the form of solid pieces in the commercial nutra​REV machine, but in order to take advantage of the potential energy savings over freeze drying, products should be less than 50 percent moisture content. Because of the rotating basket design of the feed system, the machine does not yet work with fragile fruit if the user wants to keep it in its original appearance,”​ said Thompson.

Blueberry and probiotic deals​

Last month, EnWave completed the first sale of its nutraREV equipment to Cal-San, one of the largest blueberry producers in British Colombia. The deal also includes a licensing and royalty agreement, which provides Cal-San with the exclusive license for the use of the technology with blueberries in several west coast states.​

Another technology developed by EnWave – powderREV – is currently being used by Danish ingredient giant Danisco, which is testing its applicability to the production of probiotics.

PowderREV, which also uses vacuum microwave technology, is designed to produce powder from liquids. The objective of the agreement between EnWave and Danisco is to create a dehydration method that delivers high-speed continuous bulk powder processing that can handle sensitive biological materials, such as cultures.

“We believe that we will be able to dry anything that has 20-25 percent solids (ie milk texture) using the prototype ​powder​​REV machine, but we would need to test every material individually to determine viability if we are using material which contains live or active ingredients,”​ Thompson told NutraIngredients-USA.com.