Studying the Penetration Ability of Various Pathogenic Bacteria into Raw Beef Meat Surface and the Antibacterial Effect of Ozonated Water

Abstract

Colonization of meat with bacterial pathogens potentially affects the quality of the meat products. This study aimed to determine the penetration ability of psychrotolerant bacterial pathogens into the surface of red beef meat. The penetration experiment was carried out on raw beef meat to see how different time intervals (1 day, 2 days, and 3 days) and temperatures (5°C, 15°C, and 20°C) affected the penetration process. When bacteria are found at a depth of about 2 cm in the tested meat block, this is considered a positive penetration occurrence. In this study, the action of ozone treatment (at variable exposition times) on the bacterial loads of beef meat samples in which bacterial penetration occurred was evaluated. The formation of ozone was accomplished by utilizing an O3 generator (A2Z/AQUA-6, USA). The O3(ppm) concentration in water was defined using the HI 38054 Ozone Test Kit (Hanna Instrument®, USA). The results of bacterial penetrability suggest that at low temperatures, the rate of germ penetration onto the meat surface decreases. The results revealed that the penetration rate increased in the case of dual and triple bacterial species. This can be explained by the fact that all the bacterial species that were used in the study are actively motile and have proteolytic activity. These proprieties together absolutely play a major role in the acceleration of the penetration process by these bacteria, or even so, their existence together is synergistic for migration deeper into meat. To ensure freshness and public health protection, raw meat must be treated and processed in a sanitary manner. Under the conditions used in this study, a concentration of 0.5 ppm of O3 was found to be highly effective in reducing the bacterial count in meat blocks. This decline was aided by rising the exposing time to 45 minutes to achieve 3 log10 CFU/ml-1, and the bacterial count diminished with increased exposure time to ozonated water at the same concentration. These results suggest that O3 treatment could be used to lay the groundwork for a new method of reducing meat contamination by foodborne bacterial pathogens.