What is High-Pressurized Pasteurization (HPP)?
Updated: Jan 25
High-Pressurized Pasteurization (HPP) is a cold pasteurization technique by which the raw food is introduced to a high level of isostatic pressure provided by water. This process pasteurizes the food, all living bacteria, enzymes, and microorganisms are killed.
HPP premade raw companies state, "the HPP process is 100% natural and recognized by the FDA and USDA as an anti-pathogen treatment". While HPP is an excellent way for many companies to comply with the FDA, this causes there to be two kinds of "raw" foods on the market: sterile and raw.
HPP works by applying high hydrostatic pressure to the product. High hydrostatic pressure is created by a liquid water bath that surrounds the product.
The pressure is applied from all sides, which keeps the product's shape. HPP is USDA-approved for being 100% natural and states that it does not undergo severe chemical change. HPP successfully removes all pathogenic microbes such as Listeria, Salmonella, and E. Coli. This process is used on both pet and human foods.
Depending on the recipe, the food can undergo hydrostatic pressures between 100 and 1,000 MP (below sea level) and is applied for 1 to 6 minutes.
Proteins and enzymes may be denatured depending on the amount of pressure used. Denaturing means altering the natural qualities of the food. This rids the raw food of the benefits of microorganisms. For this reason, many believe that HPP should not be called "raw." The removal of all living microorganisms directly affects the health and diversity of the gut biome.
The HPP process does rid foods of pathogens, which means all bacteria, including beneficial. The feeding of sterile foods is inorganic, but there is a higher chance of recontamination from spores, bacteria, and more. Many HPP foods are recalled due to recontamination. Since the food is sterile, it invites more pathogenic bacteria changes after processing and opening the package.
Many experienced raw feeders do not fear any bacteria contamination as they use proper safety & sanitary measures such as hand washing and cleaning work surfaces. Healthy dogs also naturally have 36% salmonella in their GI tract, and they are equipped to deal with such pathogens. For example, dogs can lick their rears and eat their own feces without becoming ill.
Furthermore, HPP changes in color, taste, and texture due to myoglobin changes, making the food a "cooked" appearance. This prevents HPP meats from being sold as "fresh meat." Companies will often remix the food as HPP changes the color to a more pale color, which opens more chances for harmful bacteria to be introduced into the sterile environment.
HPP can be a middle ground for those weary of bacteria contamination from raw food. It can also benefit pets who cannot consume 100% raw foods if they are immune-compromised. Pets with compromised GI systems such as dysbiosis may not have the healthy flora needed to handle normal bacteria levels from raw foods.
Veterinarians also tend to be more open and accepting of HPP "raw" diets as it is theoretically safer to feed. This process also increases the shelf-life and gives consumers a "fresher" product. With the FDA becoming stricter on raw feeding companies, HPP is an easy way to ensure that they still offer "raw" food.
Like any food, HPP does still pose a risk for contamination if not handled properly. Do not leave a bag of HPP food out and deem it "safe" since it's undergone the HPP process. Ensure to use proper handling and sanitary practices with any food you feed. I hope you learned something new today & Always Keep Exploring!
Choosing What's Best
In the end, it comes down to what you're comfortable with. HPP has pros and cons, and it is up to you to choose!
While fresh raw foods are optimal, HPP does have its place for those weary of raw and immune-compromised pets.
To find out if a food has undergone HPP, you can search on the company's website or contact them. Down below is a list of some premade raw brands that undergo HPP:
Stella & Chewy's
Steve's Real Food
Nature's Variety Instinct
Primal Pet Foods (Poultry recipes only)
We Feed Raw
North West Naturals
HPP raw foods are still significantly better than processed foods, but with more companies implementing HPP, it's important to weigh the risks and benefits between HPP and non-HPP. You have the ultimate power to do what is best for you and your animals!