High pressure processing (HPP) (also known as high hydrostatic pressure - HHP) is a non-thermal alternative to thermal pasteurization, which is gaining popularity as consumers continue to demand foods that maintain their freshness, offer a clean label, and deliver superior sensory and nutritional characteristics compared to heat-treated products.
HPP is commonly applied when products are in their final package, and as such can be used as a terminal process for both food safety and shelf life extension.
Prerequisites for HPP treatment include:
- Foods must be packaged in flexible containers that allow the transmission of pressure and can withstand the high pressures without rupturing or leaking.
- HPP-treated foods should contain minimal amounts of air or dissolved gasses.
Three types of customized services offered at the HPP Validation Center
- Products will be inoculated in the typical product container or package with the representative foodborne pathogens (i.e. Listeria monocytogenes, E. coli O157:H7, and Salmonella strains)
- Cocktail of 5 strains for each pathogen will be used for inoculation.
- Inoculated samples will be treated with varying pressures (max. 87,000 psi) for varying times (typically up to 10 min) or the or the pressure/time combination previously established for that product.
- Samples will be analyzed for surviving pathogens using standardized FDA Bacteriological Analytical Methodology.
- Target pathogen inactivation: 5-log (99.999% reduction). The pressure and time capable of achieving this reduction will be reported in a formal write up to the client, as HPP processing conditions to meet the regulatory requirements for pathogen inactivation.
Shelf Life Studies (microbiological and physicochemical analyses):
- NO pathogens will be inoculated into the food samples.
- Packaged food products will be treated with varying pressures (max. 87,000 psi) for varying times (up to 10 min), or the pressure/time combination showing a 5-log reduction of pathogens for that product.
- HPP treated samples will be evaluated for spoilage bacteria, yeast, and molds, at typical refrigerated temperatures or accelerated shelf life temperatures for up to 6 months. Samples can also be tested for pH, soluble solids contect, turbidity, viscosity, color, texture, and product quality aspects specific for the product, if requested.
- Microbiological sampling will occur throughout the shelf life of the product, and sampling times will vary depending on holding temperatures
- NO consumption of product will be permitted, and the samples must be retained in the BL2 facility until disposal
To Request an HPP Testing Request Form please email Andy Humiston at GAH78@cornell.edu
*Pricing scheme available upon request.
If you have any questions for us about High Pressure Processing (HPP) safety validation studies, microbiological shelf-life studies, physicochemical evaluations or any of our other value added services, please reach us through the contact information listed below.
HPP Validation Center, Cornell University
Randy Worobo, Ph.D.
Professor, Department of Food Science, Cornell University
630 West North Street, Geneva, NY 14456
Phone number: 315-787-2255