Food Engineering
TECH FLASH

Fresh juice processor automates pasteurization with continuous process

Holland’s Hoogesteger first in Europe to use pulsed electric field technology to treat fresh juice

November 28, 2012
Fresh juice processor automates pasteurization with continuous process

This PEF pilot line is installed at Food & Biobased Research, Wageningen UR in Holland (PEF unit is circled). FDA approved this process as a safe alternative to fresh juice in the 1980s under FDA Juice HACCP-66 FR6137. The Hoogesteger project was an award nominee at the 2012 Food Valley Awards, which were held in Arnhem, the Netherlands in October.

Hoogesteger BV of Zwanenburg, the Netherlands, has been selling unpasteurized freshly squeezed juices under its own brand and to private label operators for several years. The juices, whose appeal is their close taste to truly fresh juices, are produced and distributed cold under rigorous hygienic standards. The juices have a shelf life of one week, which until recently, has considerably limited their market reach outside Holland.

To extend its geographical market for these products, Hoogesteger wanted to find a preservation method gentle enough to maintain outstanding flavor, while extending shelf life to 21 days or more. In its search, the company teamed up with food scientists and process specialists at Food & Biobased Research, Wageningen UR in Wageningen, the Netherlands, considered the “Silicon Valley” of food R&D in Holland.

The two companies chose to focus on pulsed electric field (PEF) technology as a possible solution. PEF, as a mild preservation method for foods, is not new, but its application to freshly squeezed juices is, especially in Europe.

Fresh juice processor automates pasteurization with continuous process inline

Market demand for Hoogesteger BV’s fresh juices and smoothies continues to grow. PEF treatment does not affect the taste or nutrient content of these products, but does extend their shelf life from seven to 21 days.

The PEF unit preheats incoming fresh juice to about half of the normal pasteurizing temperature, which conditions the microorganisms to the treatment to come. An instant later, while the microorganisms are “exposed,” the machine applies a micro-burst of electricity to the juice through two opposing electrodes.

The PEF treatment creates pores or “holes” in the membranes of the microorganisms, causing cell components to leak, eventually causing the cells to die. The result is an extension of the product’s refrigerated shelf life to 21 days from its previous seven days. The product has virtually the same taste, color and nutritious quality as before, thanks to the low processing temperature used. Longer shelf life also means less product waste from lower past-code date returns.

“We’re delighted to be working with Hoogesteger on this project and, now that it’s launched commercially, to continue our work in upscaling the process to meet growing market demand for their juices,” says Marjolein van der Glas, business development manager, food and biobased research at Wageningen UR.