Cold plasma for food processing

Authors: Niemira, Brendan; Bermudez-Aguirre, Luz; Boyd, Glenn; Sites, Joseph

Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 11/6/2022
Publication Date: 10/16/2023
Citation: Niemira, B.A., Bermudez-Aguirre, L.D., Boyd, G., Sites, J.E. 2023. Cold plasma for food processing. In: Smithers, G.W., editor. Encyclopedia of Food Safety. 2nd edition. Elsevier: Academic Press. p. 591-598. https://doi.org/10.1016/B978-0-12-822521-9.00076-9.
DOI: https://doi.org/10.1016/B978-0-12-822521-9.00076-9

Interpretive Summary: The manuscript presents a review of conventional and novel technologies for egg pasteurization. The need of alternative technologies to common thermal processing is emphasized. Heat in conventional thermal processing usually degrades the egg quality because of the long processing time to inactivate pathogens. Some novel technologies for egg pasteurization are presented and their effects on microbial inactivation are discussed. Furthermore, some parameters related to the egg quality are presented using novel technologies. This review shows radio frequency processing in egg pasteurization as one of the best options to provide safe eggs with high quality.

Technical Abstract: Salmonella Enteritidis is a pathogen related to many foodborne outbreaks involving eggs and egg products. Regulations about whether eggs should be pasteurized or not are very different and inconsistent worldwide. In the United States, eggs are not required to be pasteurized. Hence, less than 3% of the eggs in the country are pasteurized. The standard pasteurization method uses a long thermal process that increases the cost of the product and affects its quality. Foodborne outbreaks can be reduced if eggs are properly pasteurized to inactivate Salmonella spp. However, the technology to pasteurize eggs needs to offer a faster and reliable method that can be scaled up to industry settings at a low cost and without affecting the product quality. Several novel technologies have been tested for egg pasteurization and disinfection. Some thermal technologies have been evaluated for the inside pasteurization of eggs. Microwaves have limited penetration depth and are therefore a technical challenge for shell egg treatment. However, radio frequency can penetrate shell eggs effectively to inactivate Salmonella, considerably reduces processing time, and maintains the quality of the product. For surface cleaning of the intact egg, nonthermal technologies such as ultraviolet, pulsed light, cold plasma, ozone, or natural antimicrobials have been explored as alternatives without affecting the internal quality. This review presents some of these novel technologies. It discusses the possible combination of factors to achieve the internal pasteurization of the egg and the disinfection of the eggshell without affecting the quality, at a low cost for the consumer.