Non-Thermal Processing


Alternative Food Processing Methods to Enhance Microbial Safety and Quality

Keeping Produce and Shellfish Safe to Eat Without Heat

Traditional food processing relies on heat to kill foodborne pathogens (bacteria, viruses, and parasites) to make food safe to eat. Researchers have been studying nonthermal processing methods (methods that do not use heat) that will destroy pathogens and keep foods safe to eat, while retaining sensory attributes and nutrient content similar to raw or fresh products.


Exploring Specific Nonthermal Processes to Enhance the Safety of Produce and Shellfish

Foods treated with nonthermal processes are safer to eat than untreated products (e.g., oysters, sprouts) but still require refrigeration to delay spoilage. However, as with any traditional processing method used to preserve food and keep it safe, such as canning or pasteurization, a processor must validate that the nonthermal method will work to destroy the specific, targeted pathogen(s) in their specific product.

There are strict scientific parameters and data criteria that must be achieved to establish equivalence - you cannot just use a method and hope it works! The same nonthermal method and processing parameters that may work on, say, a fruit puree or salsa may not work on oysters or whole blueberries.

Nonthermal processing methods that are currently being explored as part of this project for a variety of ready-to-eat products include:

  • High Pressure Processing (HPP)

  • Gases (ozone, chlorine dioxide, cold plasma)

  • Light (ultraviolet, pulsed light)

  • Chemical (chlorine, surfactants)

  • Ionizing radiation (gamma irradiation, electron beam)


Copyright 2015, New Mexico State University Board of Regents. These animations were developed to support "Non-Thermal Food Processing Methods to Enhance Microbial Food Safety and Quality," a multi-state, collaborative project funded by USDA-NIFA #2011-68003-30005 and including personnel from the University of Delaware, Ohio State University, Cornell University, the University of Rhode Island, Oregon State University, Delaware State University, the University of Cincinnati and USDA ARS Eastern Regional Center. The universities named are equal opportunity/affirmative action employers and educators, in cooperation with the U.S. Department of Agriculture.

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