Andersen & Sons Pasteurization

At Andersen & Sons, attention to consumer demands is a key component of our family business. We live in a time where consumers rightfully want to know every growing and handling step that their food goes through, from farm-to-table. We are committed to providing this level of transparency on all the walnut products that we supply.

We have partnered with John Bean Technologies Corporation and installed a new pasteurization system. The Stein JSP-1 Jet Stream Pasteurizer uses a steam and heat treatment method that eliminates salmonella and other pathogens without compromising the integrity of the raw nut. The JSP-1 is like no other pasteurizer. It operates at high temperatures yet processes the product passing through with virtually no damage to the nut surface.

Andersen & Sons Pasteurization Manager, Christopher Shaw, explains the key components that set the JSP-1 apart from other systems.

“The JSP-1 has two chambers. The first is a concentrated steam environment which encapsulates the nut surface. The second chamber is a high velocity heat impingement process that treats the product from top to bottom while maintaining tight moisture parameters as it exits the machine. The result is product that is not saturated in moisture and is already drying out.”

“After the nuts have been heat and steam treated they enter the chiller to start cooling. Complete cooling to ambient room-temperature is achieved within two minutes.”

How does this system perform better than other pasteurizing systems?

“PPO systems use a chemical treatment to achieve pasteurization. Other pasteurization methods use steam in a vacuum chamber environment. Both of these methods can noticeably degrade the product quality.”

“The JSP-1 achieves a 5-log pathogen reduction so quickly that the nut quality is preserved.”

Our customers demanded it and we listened.
- Michael Andersen, VP of Sales
Michael Andersen, Vice President of Sales, says the JSP-1 gives tree nut processors across California an opportunity to achieve the same high quality.

“The other methods out there put the walnuts under a vacuum, heat-and-steam treatment for longer than 30 minutes which impregnates the walnuts with moisture. The JSP-1 steams the outside for just a short period of time, less than 90 seconds, then the walnuts are immediately cooled to room temperature in under 120 seconds. The whole process takes about 4 minutes.”

As industry quality standards continue to rise, it has never been more important to choose the right pasteurization system. Michael explains why Andersen & Sons chose the JSP-1:

“The JSP-1 limits liability of recall structures. There are no chemicals and is approved for organic product. Our customers demanded it and we listened.”

Andersen & Sons installed the JSP-1 and is available to serve others in the industry.

“It is a really good option for Northern California handlers and packers in both almond and walnut industries. We are ready for anyone who needs our services.”

More Information

For further information about the Stein JSP-1 Jet Stream Pasteurizer and the pasteurization services that Andersen & Sons provides, please contact Michael at 530.839.2236 or