What Is High Pressure Processing (HPP) and Why Is it Better Than Pasteurization?

High pressure turns coal into diamonds. It also makes Little West cold pressed juice safe for everyone (yes, that includes pregnant women and people with weakened immune systems!) and extends the refrigerated shelf life of our juices without using heat (a.k.a. pasteurization) or chemical preservatives. 

Thanks to a method called high pressure processing (HPP), every bottle of Little West retains peak nutritional value and tastes just as fresh as the day it’s juiced. Now that’s im-press-ive.

So what is high pressure processing, and why do we use this method instead of pasteurization? Here’s a hot hint: it’s all about the temperature. Our juices are too cool for old skool sterilization, literally. Pasteurization is an effective way to kill harmful bacteria and food borne pathogens, but it also “kills” the health benefits of cold pressed juice by heating it. 

High pressure processing makes our juices just as safe as pasteurization, but it uses pressure instead of heat. It allows Little West cold pressed juice to remain raw, healthy, and delicious. Wondering how it works? Let’s put on our geek glasses and take a closer look:

Pasteurization vs. High Pressure Processing (HPP): A History

Although it’s named after French chemist Louis Pasteur, the pasteurization process -- heating liquids to reduce the risk of disease and extend potability -- actually dates back to eleventh century China. Around 1117 AD, the Chinese heated their wine. The Japanese used a similar technique for sake in the 1500s.

But Louis Pasteur popularized the practice in the West in 1864. He proved that heating freshly fermented wine killed the microbes that caused it to taste acidic as it aged. Pasteur’s method was soon adapted to beer, then to milk, juice, and other beverages. In the United States, the first mandatory pasteurization laws went into effect in 1947. 

Today, pasteurization involves heating liquids at a high temperature for a short time. This is sometimes referred to as “flash” pasteurization. Most commercial juices, like big brand orange juice, are heated to 160 degrees Fahrenheit (or above!) for 10-30 seconds. Then, the juice is refrigerated or frozen in cold storage, sometimes sitting in a vat for months before bottling.

High pressure processing, also known as pascalization, also shares a French origin story. The technique was inspired by Blaise Pascal, a French mathematician who studied fluid dynamics in the 1600s. According to Pascal’s Law, when pressure is applied to a fluid inside a closed container, the pressure will be distributed evenly. 

Over 200 years later, Pascal’s work inspired chemists in the United States at the West Virginia Agricultural Experimental Station. They discovered that applying high pressure to liquids in a closed container killed the pathogens and microorganisms responsible for food borne illnesses. Thus, high pressure processing was born! 

How High Pressure Processing (HPP) Works

First, the fresh juice is hermetically sealed in a sterile, BPA-free bottle. (“Hermetically sealed” means the bottle is completely airtight, which prevents oxygen, other gases, and airborne contaminants from getting inside and spoiling the juice.)

Next, the bottles are loaded into a high pressure processing machine. They’re placed within a special chamber called a “pressure vessel.” After all the bottles have been loaded, the pressure vessel is sealed with two plugs and braced with an industrial yoke.

Then, the pressure vessel fills with cold water. The water is pressurized until it reaches 85,000 to 87,000 psi. For comparison, the pressure at the deepest point in the ocean, the Mariana Trench, only reaches 15,750 psi!

This high pressure is uniformly applied to all juice bottles inside the pressure vessel. After the designated amount of seconds, the vessel is depressurized. The bottles are unloaded, dried, inspected, and ready to drink! 

A Difference You Can Taste 

Using high pressure processing (HPP) is just one of the ways Little West stands apart. By making our juices safe without heat, high pressure processing enables us to provide cold pressed juice that’s packed with raw nutrients and fresh, crisp taste.

Discover the benefits of our juice cleanse and juice subscription options. Find Little West cold pressed juice at Whole Foods locations in California, Nevada, and Arizona or order online. Free shipping on all orders of 12 bottles or more!