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ARS Home » Northeast Area » Wyndmoor, Pennsylvania » Eastern Regional Research Center » Food Safety and Intervention Technologies Research » Research » Publications at this Location » Publication #319851

Title: Inactivation of Staphylococcus saprophyticus in chicken meat and exudate using high pressure processing, gamma radiation, and ultraviolet light

Author
item Sommers, Christopher
item Scullen, Butch - Butch
item MACKAY, WILLIAM - Edinboro University Of Pennsylvania

Submitted to: Food Control
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/14/2016
Publication Date: 12/22/2016
Citation: Sommers, C.H., Scullen, O.J., Mackay, W. 2016. Inactivation of Staphylococcus saprophyticus in chicken meat and exudate using high pressure processing, gamma radiation, and ultraviolet light. Food Control. 75:78-82.

Interpretive Summary: Staphylococcus saprophyticus is a common contaminant in meat and poultry and is a significant cause of urinary tract infections (UTI). Women are at particular risk of UTI from this microorganism. The Centers for Disease Control and Prevention recommends foods treated with non-thermal processing technologies for individuals with underlying conditions which may make them susceptible to illness. In this research we determined the inactivation kinetics of S. saprophyticus in chicken meat and exudates (purge), using high pressure processing (HPP), gamma radiation (GR), and ultraviolet light (UV-C), all of which are green and sustainable food safety technologies which are in commercial use. In our research we found that HPP and GR can kill ca. 99.9 – 99.99% of S. saprophyticus in chicken meat using conditions that do not affect product quality. In addition, we found that a modest UV-C dose of 120 mJ/cm2) can kill 99.99-99.999% of S. saprophyticus in chicken exudates on food contact surfaces such as stainless steel and plastic, and ca. 50% on skinless chicken breast pieces. The results of this study will allow regulatory agencies, women’s health groups, and the food processing industry to conduct risk analysis and provide safer meat and poultry to consumers. Consumers will benefit from having more information about foods treated with alternative processes such as HPP, GR, UV-C.

Technical Abstract: Stapylococcus saprophyticus is a common contaminant in foods and causes urinary tract infections in humans. Three nonthermal food safety intervention technologies used to improve the safety foods include high pressure processing (HPP), ionizing (gamma) radiation (GR), and ultraviolet light (UV-C). A five isolate cocktail of S. saprophyticus was inoculated into ground chicken which was then treated using HPP (5 degrees C, 0-25 min) at 200, 300 or 400 MPa. HPP D10, the processing conditions needed to inactivate 1 log of STEC, was 15.5, 9.43, and 3.54 min, respectively. When the S. saprophyticus cocktail was inoculated into ground chicken and gamma irradiated (5 and -20 degrees C) the GR D10 were 0.64 and 0.77 kGy, respectively. The S. saprophyticus cocktail was inoculated into chicken exudate which was then placed on food contact surfaces including stainless steel, and high density polyethylene and polypropylene and treated with UV-C (0-120 mJ/cm2). UV-C D10 ranged from 14.9 – 18.5 mJ/cm2. UV-C (100 - 120 J/cm2) inactivated ca. 0.4 - 0.5 log of S. saprophyticus on skinless chicken breast meat. These results indicate that nonthermal processing technologies such as HPP, GR, and UV-C can be used to kill S. saprophyticus in poultry meat, decontaminate exudates on food contact surfaces, and reduce the risk of foodborne illness for consumers.