The objectives of this study were to determine the impact of packaging methods and temperature abuse on the pathogen loads in ground beef inoculated with E. coli O157 and Salmonella and on the spoilage characteristics and shelf life of ground beef.
Increases in numbers of E coli O157:H7 in ground beef were higher in the overwrap (OW) and high oxygen (OX) packaging treatments than carbon monoxide (CO), no oxygen (NO), and vacuum (VAC) packages during temperature abuse. Salmonella counts did not differ among packaging treatments during temperature abuse. Ground beef packaged in CO exhibited an extended shelf, less odor development, greater color stability and less oxidative rancidity development compared to OW, OX, NO and VAC packaging treatments. Trained panel, 97%of panelists, detected some type of off-odor in the packages after the 20-day storage and display period. Conversely, 20% of consumers were unable to detect off-odors in all packages and indicated they would consume the ground beef based on its odor regardless of packaging type. With the exception to meat color, CO and VAC packaged exhibited similar color, odor, TBA and microbial characteristics. A significant percentage of consumers would purchase and consume ground beef packaged in CO after 5 days of temperature abuse and 15 days of lighted display.
Under temperature abuse scenarios, packaging type effected the prevalence of E coli O157:H7 in shelf-life and organoleptic studies. Low oxygen packaging techniques resulted in extended shelf life, less odor production and reduced oxidative rancidity development compared to oxygenated packaging techniques.