Back in grade school (which admittedly goes back further than I care to admit), Mom wrapped my sandwich in waxed paper and put it in a brown craft bag with a piece of fruit. As far as food protection went, that was about it. In those days, the stale life of a PB&J was about as long as it took to get to lunch hour. Later, about the time I got into the hot lunch program, plastic sandwich bags had come along and fixed that problem. Sadly, it was a bit too late for me.
However, what still remains an issue, even up to today, is not necessarily how to prevent bread from becoming stale but how to prevent foods from spoiling. It’s a challenge as old as mankind, but we’ve made some progress over the years. From dehydrating to salting, brining, canning, freezing and cryovacing, each successive new method of food preservation has not only prolonged the shelf life of perishable foods but also advanced civilization in countless ways, from the initial building of cities far away from farms to exploring galaxies far away from our own planet. Now, another chapter in the ancient history of food preservation schemes is just becoming mainstream. It’s called High Pressure Pasteurization or HPP for short. What’s High Pressure Pasteurization?
While it’s rather new to you and me, HPP has been around for centuries (or at least the theory of it). To some, it’s known as “Pascalization,” named after Blaise Pascal, a 17th-century French scientist who studied the effects of pressure on fluids. His technique, which used more than 50,000 pounds per square inch of pressure applied for about 15 minutes to foods, resulted in the rupturing and (as a result) inactivating of the cells of pathogenic bacteria like salmonella, E. coli and listeria. As it turned out, HPP affects food cells and disables the unwanted pathogenic microorganisms that cause food to spoil.
Nowadays, pressures of up to 120,000 pounds per square inch (PSI) are occasionally used (and that’s more than 10 times greater than the pressure exerted on things in the deepest part of our deepest oceans). Now, you might think all this pressure would totally squish anything into some unrecognizable something. Nope.
In a typical HPP process, the food is packaged in a flexible container and loaded into a pressure chamber filled with water. The fluid (normally water) in the chamber is pressurized with a pump, and this pressure is transmitted through the package into the food itself. Pressure is applied and maintained for a specific amount of time, usually about 3 to 5 minutes. Now, because this enormous pressure is transmitted uniformly (in all directions simultaneously), food retains its shape, even at these extreme pressures. When the time is up, the water is drained, the pressure released (again evenly) and the finished product is removed, stored and distributed in its usual manner. Best of all, because no heat and no preservative chemicals are used or needed, the characteristic quality and integrity of the food is retained without compromising its microbial safety.
What’s not to like? No heat added, no preservatives needed, minimal if any vitamins lost with the same great texture and flavor and a much longer shelf life. In some cases, a product with a shelf life of one week is safely extended to two months! Top it all off with the added benefit that the HPP process is what’s called a sustainable technology. For the most part, you only need water and electricity to make it all happen.
Although HPP is an extremely effective means of extending the shelf life of many products, such as guacamole, fruits, yogurt, and vegetables (especially acidic ones like tomato products), it’s still necessary to refrigerate many HPP products to maintain their wholesomeness.
Where will you find HPP products at Nino’s?
HPP listings aren’t required on labels, so you won’t always know what’s been pressure packaged. Fortunately, its lack of preservatives and long shelf life WILL give you a clue. One product on our shelves, Garden Fresh Salsa of Ferndale, Michigan, was among the leaders in the HPP industry. Jack Aronson, Garden Fresh Gourmet’s founder, can proudly boast that it is one of THE first privately held companies in America to install an HPP system. The company installed it about six years ago.
Garden Fresh HPPs all of its natural products, except for a few high-pH salsas. “It’s expensive,” Jack admits. “It adds about 15 to 20 cents a pound to our products, but we’re not a commodity item. We sell high-quality salsas and dips. It’s worked out perfect for us.” Currently, the majority of Garden Fresh Gourmet’s 100-plus products are preservative free. Aronson says, “Eventually everything we do is going to be all-natural, and HPP is a big part of that.”
High Pressure Pasteurization is a new tool in the arsenal of spoilage warfare and one I’m excited to watch in the coming years as the prices for these machines get cheaper and more within the reach of smaller businesses. Who knows? Perhaps someday in the future we’ll all have a small HPP machine on our kitchen counters, right next to the microwave. Our leftovers will last for months!
Actually, I’m not really sure that’s a good thing… For now, I’d just be happy if I could remember to reapply the twist tie to my loaf of bread. I suppose I just got used to those stale PB&J’s.