High Pressure Processing (HPP) is widely used to pasteurize food, but most food producers ‘hide’ the method because of consumer perceptions, a HPP consultant said.
“Right now almost all companies that HPP their products do not advertise this process,” said Gerald Ludwick, CEO, All Natural Freshness in Michigan.
“They hide the fact that they HPP the product for fear of consumer backlash for fear of understanding.”
HPP is a technique which kills microorganisms and enzymes using extremely high pressure. Machines surround food with cold water and pressurize it for about 15 minutes at forces up to 87,000 lbs per square inch. The process kills yeast, mold and bacteria, preserving food for longer.
HPP’s advocates claim the technique keeps products stable without losing taste or nutrition associated with traditional sterilization methods.
The technique can “double or triple the existing shelf life” added Ludwick.
Consumers “throw away” HPP meat
Ludwick believes the extra shelf life of pressure-processed foods could differentiate brands in a fierce market, but consumers need more education on how it affects products.
“HPP can give foods 90-120 days shelf life with no preservatives. But the issue is the consumer isn’t going to eat it,” he said.
“A few months back, I did a presentation for a large grocery chain. The grocery's chef was very excited about all the possibilities for extending the shelf life and bringing fresher products to the store level.
“We took the example of fresh hamburger patties that could be flash-grilled, processed via HPP, then vacuum-sealed and sold in the deli section with a shelf life of 30 days. But if you took them home and your spouse asked how long had they been in the refrigerator and you said two weeks, the spouse would throw them away".
“Folks won’t be too excited about eating a tomato you can’t see”
There are other hurdles to consumer acceptance, claims Ludwick. For example, HPP can have unusual effects on food color.
Fresh tomato and onion turn translucent after pressure processing because of liquid loss. “Folks won’t be too excited about eating a tomato you can’t see,” said Ludwick.
But companies have started introducing “natural” buffers, such as vitamins, which cause the vegetables to retain water and therefore their color.
Nature Seal is one company providing these buffers to maintain color, texture and flavor. A.J. Martinich, director of sales, claimed the firm's buffers for fresh-cut produce are being used by clients in more than 40 countries.
“Although we are best known for our applications for sliced apples, we also have very effective products for fresh-cut avocados and potatoes,” he said.
Making rare hamburgers “safe”
Treating meat with HPP provides its own problems and benefits.
Hamburgers are a traditional hazard unless cooked well done because mincing meat grinds up bacteria into the inside of the burger.
Because HPP “penetrates the whole product, inactivating the listeria”, burgers can be safely eaten rare, claimed Ludwick.
But the marketplace remains a huge hurdle, he said. After HPP, raw beef will oxidise and turn brown, even though it has not been cooked, and once cooked, “even though it’s medium rare it doesn’t look medium rare”.
“It’s hard to sell retail consumers on the product”, he said, but restaurants could be more amenable.
“Perceptions need to change, ” said Ludwick, but added HPP companies lack the funds for the massive PR campaign needed.
“Maybe someone with a lot of money that can get the word out – Walmart, for instance.”
“It’s always dollars,” he added.