Control of Escherichia coli O157:h7, generic Escherichia coli, and Salmonella spp. on beef trimmings prior to grinding using a controlled phase carbon dioxide ([subscriptCP]CO[subscript2]) system
1500 psi CPCO2 for 15 min achieved 0.83, 0.96, 1.00, and 1.06 log reductions for Total Plate Count (TPC), Generic E. coli (GEC), E. coli O157:H7 (O157), and Salmonella spp. (SS), respectively. Bacterial reductions in ground beef and beef trimmings were similar (P?0.05).
CIE L*, a*, and b* values in raw patties showed no differences (P?0.05) immediately after CPCO2 application on beef trimmings. Nevertheless, significant (P<0.05) interactions were found in pressure by packaging for L*, in pressure by packaging by days of simulated retail display for a*, and in packaging by days of simulated retail display for b* scores. Nevertheless, after 5 days of simulated retail display, L*, a*, and reflectance (630/580nm) ratios were similar for all treatments (P?0.05), and b* scores were most acceptable with 1500 CPCO2 (P?0.05), regardless of the packaging conditions.
After 5 days of display, cooked patties showed similar (P?0.05) values for crude protein (%CP) and crude fat (%CF), the extent of lipid oxidation (TBARS), was higher (P??0.05) in aerobic trays than flushed packages with 100% CO2.
Ground beef patties manufactured from beef trimmings treated with CPCO2scored higher values for tenderness (P??0.05) than other treatments. In addition, no differences (P?0.05) for juiciness, beef flavor intensity, or off flavor intensity were found between non-treated and the 1500 psi CPCO2 treated patties.
Microbial control of spoilage organisms and foodborne pathogens in ground beef patties with CPCO2 application in beef trimmings was effective (0.6 to 1.2 logs). Lethality levels are comparable to other intervention strategies. Discoloration of beef trimmings after CPCO2 application may not be a concern for grinding purposes. Further packaging with 100% CO2 is viable for controlling spoilage and pathogenic microorganisms after packaging and during refrigerated storage, although discoloration of raw ground beef patties packaged with 100% CO2 may be a concern for product marketing.
School:Kansas State University
School Location:USA - Kansas
Source Type:Master's Thesis
Keywords:carbon dioxide pathogen control ground beef antimicrobial trimmings agriculture food science and technology 0359 biology microbiology 0410 health sciences public 0573
Date of Publication:01/01/2006