In the world of food safety, it’s not just about food poisoning outbreaks and recalls. Sometimes there’s some good news to share. That’s the case in breakthroughs and advances in science and technology that can stop foodborne pathogens dead in their tracks. And sometimes that sort of news appears in unexpected places.

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Take, for example, the January edition of Popular Mechanics. In a section about the “Ten Tech Concepts You Need to Know,” readers learn that “this year’s big ideas in tech will make your food safer, make hybrid cars more energy efficient, and sentence overpriced texting plans to death.”

Right out of the gate, at the top of the list, is a USDA-approved food-safety process that the magazine refers to as “Pascalization,” commonly known in the food industry as HPP, or high pressure processing. And while it’s only been used on the commercial level for the past 2 decades or so, the technology has been around far longer than that.

Turns out that none other than French scientist, mathematician  and philosopher Blaise Pascal (1623-1662) conducted research on food preservation. What he came up with — high pressure processing — is what  Popular Mechanics describes as “changing the way we think about food.”

This process doesn’t rely on heat, such as pasteurization; or chemicals, such as preservatives; or irradiation to kill the harmful bacteria on food. And while heat and cooking are good ways to kill bacteria, they can also impair the flavor, texture, color and nutrition of the food. For the most part, the same is true of irradiation.

Under high pressure processing, already packaged products such as fresh hamburger and turkey; processed fruit such as apple sauce; oysters; fish; guacamole; and ready-to-eat meats such as sliced turkey, pastrami and beef are put inside a pressure chamber. Water is then added to the chamber before it is sealed. From there, the pressure is increased to the maximum desirable level and sustained for a set period of time. The chamber is then decompressed and drained and the packaged products are removed.

We’re talking about a lot of pressure. For example, at sea level, air pressure is 14.4 pounds per square inch. In the case of products put under HPP, the pressure ranges from 60,000 to 87,000 pounds per square inch.

And while that sounds like enough pressure to squash or damage the packaged food, that doesn’t happen because the pressure is applied equally on all areas of the product.

The good news is that the pressure zaps foodborne pathogens such as E. coli O157:H7, Listeria and Salmonella, as well as “spoilage” microorganisms such as molds and yeasts — without affecting the nutritional qualities or the taste of the food products. That’s because while it has enough force to significantly disrupt cellular activity, it doesn’t affect the structures of the food components that are responsible for nutrition and flavor.

Another plus is that because HPP is applied when the products are already packaged, it eliminates the possibility of cross-contamination. In other words, the products are free of pathogens when they get to the customers, whether they be grocery shoppers, restaurants, schools or other institutions.  Even so, people preparing the food must follow basic food-safety procedures, such as washing their hands and preventing cross-contamination with other foods or cooking utensils to keep the food safe from foodborne pathogens.

But HPP isn’t a one-step-and-it’s-safe sort of approach to food safety. Companies that use it also follow standard food safety principles all the way down the line.

Last year when Food Safety News wrote about HPP, the big news was that meat-processing giant Cargill had introduced a patent-pending process for a new line of fresh hamburger patties produced under high pressure processing. At the time, the company hailed it as a “natural option for food safety” and a “technological breakthrough.” Until then, no one had figured out how to use high pressure processing on fresh hamburger meat without affecting its taste, texture or appearance.

The patties were slated for the food service industry, with customers such as restaurants saying that they were looking for a “fresh hamburger” option with good shelf life. According to a news release from Cargill, the HPP burgers have double the shelf life of non-HPP burgers. Yet the fresh flavor stays intact and food safety is enhanced.

The company’s name for these HPP burgers is “fressure.” The idea is that the fressure logo could be used on restaurant menus so customers would know the burgers were fresh, not frozen. And while the label advised that the meat be cooked to 160 degrees, the “fressure” burgers gave cooks and chefs the option to cook them to lower temperatures and therefore satisfy customers who wanted medium-rare burgers, for example. Even so, restaurant menus are required to carry a warning that undercooked or uncooked meats and shellfish can pose a risk to human health.

At the time, long-time HPP researcher V.M. Balasubramaniam, Department of Food Science and Technology at Ohio State University, told Food Safety News that this new development on the part of Cargill was “the most promising food-safety innovation in recent years.” And he predicted that the technology would become a key player in food safety.

Ten months later, he echoed similar thoughts in the comments he supplied to Popular Mechanics, pointing out that sauces, fruit juices, guacamole, lunch meats, and fish hold up well to HPP and and that treated versions of these foods can be found in stores today.

He also pointed to falling equipment costs for HPP and the demand for longer shelf life, coupled with a poor consumer acceptance of food irradiation, which he referred to as “HPP’s competition” as reasons that HPP will enter into the mainstream.

Indeed, it’s almost there, with the industry having grown into a multi-billion-dollar business in recent years, he said.

Two Heavy-Hitters

As 2011 came to an end, more news about HPP found its way into mainstream media, thanks to two heavy hitters in the food industry.

The first of these is Cargill, which once again turned to HPP, this time for some of its ground turkey. Michael Martin, spokesman for Cargill, told Food Safety News that in the wake of the company’s August and September 2011 recalls of millions of pounds of ground turkey (triggered by the possible contamination of the product by multi-drug resistant strain of Salmonella Heidelberg), the company explored all current food safety technologies to determine which could be effective at further reducing the potential for foodborne illness.

“One of those is high pressure processing (HPP), which we are using on some ground turkey products packaged in chubs,” Martin said. Chubs are thin plastic packages containing ground meat or poultry, with the ends fastened together with a metal clasp.

Martin said the company continues to evaluate the food-safety value and consumer acceptance of the product undergoing HPP, which is being done by a third-party supplier.

The second heavy hitter to enter the HPP scene late in 2011 was none other than Starbucks. With its purchase of juice-maker Evolu
tion Fresh in November, Starbucks cast its vote for HPP. In acquiring the company, Starbucks emphasized the competitiveness of high pressure processing since juices treated with HPP are never heated.

In the Starbuck’s news release about the purchase of the company, Jimmy Rosenberg, founder of Evolution Fresh and the newly named chief juice office of the company, said that using High Pressure Pasteurization (another term for HPP) to help ensure the inherent nutrients are kept intact during the juicing process is a key point of differentiation for a growing number of the company’s juices.

Rosenberg founded Naked Juice, which is now owned by PepsiCo. Another juice contender, Odwalla, was bought by CocaCola. But companies pasteurize their juices.

Starbucks plans to serve Evolution juices at juice and health bars, in stores, and also at its company-owned retail stores, thus bringing the HPP juices to the attention of about 60 million people worldwide each week.

In an email to Food Safety News, a spokesperson for Starbucks said that juices processed with HPP will be noted as such on the bottle labels.

“As more information becomes available about HPP, we believe customers will seek out these juice products,” said the spokesperson.

The news about Starbuck’s plans for Evolution juices found its way into USA Today and the LA Times, among many other mainstream media outlets.

“For us, this is exciting because Starbucks will be marketing the juice as HPP,” Glenn Hewson, vice president of Global Marketing for Avure, the global leader in HPP food processing equipment, told Food Safety News. Last year, Avure described HPP as “food safety’s best kept secret” and pointed to $3 billion in food products worldwide created with HPP each year.

Among the companies using it for all or some of their products are Hormel, Fresherized Foods, Garden Fresh Gourmet, Perdue, Puro Fruits, SimplyFresco, Maple Lodge Farms, and Wholly Guacamole.

America is the leader in HPP, with Mexico coming in second. HPP products are also being produced in Europe, Japan, Australia, New Zealand and Korea.

And while there’s an additional cost of using HPP, food companies are finding that consumers are becoming increasingly concerned about food safety and that many are willing to pay the extra cost.


When people learn about HPP, the first question they usually ask is how they can know which foods are processed with HPP.

Unfortunately, said Avure’s Hewson, many companies don’t include that information on their labels, although they do include it on their websites.

With that in mind, Hewson said that manufacturers of HPP products should consider joining the ranks of companies like Fresherized Foods, Maple Lodge Farms and Ifantis in developing HPP branding that tells consumers about the benefits on the technology right on the package.

“Processors will find that branding cements consumer awareness and drives market demand for their products that stand out from the crowd,” he said.

He predicts that before long, there will be an industry mark that signifies that HPP has been used to produce the food items that have undergone the process.

To watch some videos about HPP processing, go herehere, and here.

Companies using HPP are invited to list the products they make with the technology in readers’ comments at the end of the article.