HPP is an industry term to reference the equipment used to create Cold Pressure to apply to food and beverage products.
High Pressure Processing is recognized by the FDA, USDA, Health Canada, the EU and other authoritative bodies for preserving freshness and increasing shelf life without preservatives or high heat. The process leads to the elimination of harmful bacteria while maintaining a higher yield of vitamins, minerals and enzymes, and preserving a fresher taste.
HPP can be used on a variety of fresh food products including juices, dips, salsas, dairy, meat products, seafood products and even cosmetics. The main food chemistry component is for all products to have enough water activity for the pressure to be effective.
Cold Pressure always refers to the non-thermal technique also known as HPP. “Cold Pressed”, usually refers to the technique by which fruits or vegetables are squeezed or pressed in a machine to extract the juice from them. Once the fruits and veggies are pressed, their contents are bottled and then subjected to Cold Pressure Technology (HPP).
To achieve microbial inactivation and/or to remove chemical preservatives while providing consumer desired qualities cold pressure retains food quality maintains natural freshness and extends microbiological shelf life by inactivating most vegetative bacteria at pressures above 60,000psi
Cold Pressure Technology causes minimal changes in the fresh characteristics of foods while achieving food safety requirements. Compared to thermal processing, cold pressure results in foods with fresh taste and better appearance, texture, and nutrition. The technology is especially beneficial for thermally processed products.
Cold Pressure can be used in a broad range of foods. Typically foods with higher acid content are good candidates for Cold Pressure technology.
Some products that are commercially produced using HPP are cooked Ready-to-eat meats, avocado products (guacamole), tomato salsa, applesauce, juice, and oysters to name a few.
Cold Pressure is uniformly applied hydrostatic pressure applied to the entire food product equally and instantly.
For example, a grape placed between fingers can be easily squeezed and broken; this is because the pressure is not applied evenly from all sides simultaneously. On the other hand, if the same grape is squeezed from all sides simultaneously, it will not be crushed. This can be demonstrated by placing a grape inside a bottle filled with water. By squeezing the bottle, you pressurize the water inside the bottle as well as the grape. Yet the grape is not damaged, no matter how hard you squeeze. In the same way, foods processed by high pressure will not be damaged by the applied pressure.
Cold Pressure can extend shelf life up to 10 fold and improve food safety. Cold pressure can also provide shelf life similar to thermal pasteurization without changes to color, texture, or flavors that would have been induced by heat. As commercial products are developed, shelf life is established based on microbiological and sensory testing.
It is generally known that high pressure has very little effect on low molecular weight compounds such as flavor compounds, vitamins, and pigments compared to thermal processes. Accordingly, the quality of cold pressure treated food is very similar to that of fresh food products and the quality degradation is influenced more by subsequent storage and distribution rather than the pressure treatment. Pressure also provides a unique opportunity to create and control novel food textures in protein-based or starch-based foods. In some cases, pressure can be used to form protein gels and increase viscosity without using heat.
HPP does not present any unique issues for food processors concerning regulatory matters or labeling. The requirements are similar to traditional thermal pasteurization or sterilization in the United States, where the Food and Drug Administration (FDA) and the Department of Agriculture (USDA) are responsible for evaluating and monitoring the safety of HPP processed foods.
There are a number of research facilities throughout the world where food processors can evaluate HPP technology. Contact us for details.