HPP: A ‘Cool’ Innovation in Food Packaging

For Chris Staudt, high pressure processing (HPP) is a key that has opened new doors, professionally speaking. As CEO of Chairman’s Foods, LLC, Staudt oversees production of custom fresh and frozen products for food service and retail customers in a 40,000-square-foot plant at the company headquarters in Nashville, Tenn. and a 38,000-square-foot facility in Columbus, Ga.

“HPP is nothing new,” Staudt says, “but it has opened doors for us, allowed us to provide solutions for our customers that traditional methods would not allow.”

Simply stated, HPP is a technique by which food and beverage products, already sealed in final packaging, are introduced into a cylinder-shaped pressure chamber where they are subjected to a high level of hydrostatic pressures (43,500-87,000 pounds per square inch) transmitted by cold water. The HPP process can take from one to six minutes.

Acknowledged by USDA and FDA as a kill step, HPP is a natural process that inactivates E. coli O157:H7, Salmonella, Listeria monocytogenes, and other foodborne pathogens, with minimal impact on a consumable product’s taste, texture, appearance, or nutritional value.

Tracing its roots to the 17th century, HPP is also called pascalization, as an homage to the French scientist Blaise Pascal (1623-1662) who studied the effects of pressure on fluids; bridgmanization, after physicist Percy Williams Bridgman (1882-1961) who won the 1946 Nobel Prize for Physics for his work on the physics of high pressures; and high hydrostatic pressure, abbreviated as HHP.

In June 1899, Bert Holmes Hite (1866-1921) published a bulletin entitled “The Effect of Pressure in the Preservation of Milk,” which first documents pressure being used as a food preservation method. Hite is credited as the first person to conclusively demonstrate the inactivation of microorganisms using pressure.

Founded in 1976, Chairman’s Foods started using HPP in 2011. Examples of the company’s products include kettle cooked fillings for chicken pot pies; sous vide cooked proteins; ready to eat chicken salad and other prepared items for food service delis and steam tables; and assorted co-pack queso dips for several grocery store chains, including Whole Foods.

Speaking of chicken salad, Staudt is quick to mention that HPP has helped Chairman’s Foods attract new customers to the wildly popular comfort food.

“Many companies make chicken salad, but, thanks to HPP, we can make it using fresh ingredients, with a longer shelf-life, and a clean label with a short list of ingredients void of powders and preservatives,” Staudt explains. “Since we are not stuck with old processing traditions, we have new opportunities.”

Chairman’s Foods utilizes the HPP services of Universal Pure, shipping products to the latter’s facilities in Villa Rica, Ga., Coppell, Texas, and Lincoln, Neb. From those locations, Chairman’s arranges shipping to its customers once HPP is completed.

HPP is typically used to enhance food safety and extend product shelf life, which is the technology’s biggest economic impact, says Mark Fleck, an HPP consultant for Universal Pure. “Because HPP addresses typical spoilage organisms such as bacteria, yeast, and mold, producers realize significant shelf life increases often a two to four times improvement,” he relates. “More times than not, HPP becomes a critical control point in a food producer’s Hazard Analysis and Critical Control Points (HACCP) plan.”

Another benefit, Fleck mentions, is that HPP can also serve as a package leak detector. “HPP uses simple water pressure which is applied uniformly (isostatic) to the packages,” he notes. “If the package integrity is faulty, operators can remove the defective packages post HPP, thereby delivering 100 percent quality packaged products to their customers. Food producers can reduce or eliminate credits and chargeback expenses.”

According to Fleck, the added shelf life benefit of HPP produces savings across the production and distribution spectrum. “Manufactures may be able to produce the product less frequently and in larger batches, thereby making their operation more efficient,” he explains. “Logistics may have the option to ship full truckloads rather than LTL (less than truckload) shipments, thereby obtaining better rates. And, extended shelf life helps retailers reduce stocking frequency and minimizing out of code date products.”

Impact on Food Packaging

“The first and major consideration when selecting packaging for HPP is that the package will be submerged in water during the process,” Fleck says. “Secondly, some flexibility must be a part of the package.”