Food Engineering

Keep it simple

March 22, 2003
Ammonia chiller eliminates glycol chilling and uses direct expansion ammonia as the cooling medium.



There's nothing simple about the frozen orange juice/concentrate market. Fluctuating wholesale prices always make profitability unpredictable. And now there's a new squeeze on profits, changing customer demands on the wholesale supplier.

As more and more players enter the orange juice-based drink marketplace, existing suppliers, both retail and wholesale, are forced to find new ways to differentiate their offerings to gain their share of the consumers' dollar. One new product enhancement has been the addition of stabilized orange cells, or pulp, to the finished product to give it a more "fresh squeezed" consumer appeal.

While this may seem like an insignificant product change to the consumer, it presents a tremendous challenge to wholesale supplier executives like Paul Ballentine, vice president and plant manager at Louis Dreyfus Citrus in Winter Garden, Florida. Processing over 5,000 tons of citrus a day in its Florida plant, Louis Dreyfus is a major worldwide wholesale supplier of bulk orange juice and frozen orange juice concentrate. So when customers started requesting stabilized orange cells along with their concentrate products, it proved to be no small production challenge.

Facing increasing demand for product from wholesale customers and its own in-house retail group, Louis Dreyfus had to upgrade its entire system, which was small and inefficient, or risk losing long-term customer relationships.

According to Ballentine, the new system would have to meet very specific criteria that included price and stated performance. The new product was very sensitive to breakdown from shear, so pressure drop was very important. "The lower the pressure drop, the better to ensure gentle treatment of the pulp," Ballentine notes.

After looking at several major system suppliers both in the U.S. and abroad, Louis Dreyfus chose Waukesha Cherry-Burrell. "Their system recommendation clearly met or exceeded all our specified criteria," states Ballentine. Much of this success Ballentine attributes to the system's unique ammonia chiller.

Typically, ammonia is used to chill glycol that becomes the cooling medium that chills the product. This entails a more complicated and expensive system. The WCB system eliminates the glycol chilling step and uses direct expansion ammonia as the cooling medium. A PLC feature provides precise control of the ammonia temperature.

"The ammonia chiller adds a tremendous production efficiency. " Ballentine says. "As long as you can control the direct expansion ammonia, it's a much less expensive and more efficient way to chill your product." Ballentine adds that skipping the glycol chilling step saved nearly twenty percent in overall system equipment cost.

In addition to equipment cost savings, Louis Dreyfus also has realized an increase in revenues of twenty five percent. Ballentine attributes this to increased production and bringing on new customers.

"We specified a system for 20 metric tons of pulp a day...now we're routinely getting 25 to 28 metric tons a day. We can actually make more product than we can sell at this time," Ballentine says.

Ballentine also likes the system's automatic shut down feature. If the product fails to meet specified temperature parameters, the system goes into an automated clean up stage that cannot be bypassed by the operator.

The WCB system has a proven performance track record so far, Ballentine reports. If service is needed, the system can interface directly with Waukesha Cherry-Burrell via modem and problems can be diagnosed right away.