Chicken blood promotes growth of Listeria monocytogenes, Salmonella Typhimurium, Campylobacter jejuni and Pseudomonas aeruginosa in minced chicken during refrigerated storage

Microorganisms are typically introduced to poultry meat through cross-contamination during processing, visible matters, including residual blood can further affect levels of contamination and deterioration of the meat. This study is aimed to investigate effects of chicken blood that may be left from slaughtering process or methods typically at retail environments (fresh markets) on microbiological quality of minced chicken during refrigerated storage. Medium broth with chicken blood added at 1, 2.5 and 5 μmol/g showed no difference in the growth of Listeria monocytogenes, Salmonella Typhimurium, Campylobacter jejuni and Pseudomonas aeruginosa, compared with the no blood-added broth at 48 h of incubation. After 2 days of storage at 4°C, mesophilic and psychrophilic bacteria increased rapidly in both the minced chicken with and without blood. At 8 days of storage, minced chicken without blood showed lower counts of Pseudomonas aeruginosa, Salmonella Typhimurium, and Campylobacter jejuni (P < 0.05), except for Listeria monocytogenes. Comparison of microbial growth in minced chicken obtained from the Islamic slaughtering method (IM) and conventional neck cut method (CM) showed that only Campylobacter jejuni had higher growth in the CM-minced chicken than those found in the IM-minced chicken during 8 days of refrigerated storage. Our study suggests that chicken blood can promote bacterial growth. The conventional slaughtering process may allow for the presence of more blood residual in poultry meat or environments which could allow for higher counts of Campylobacter jejuni than in minced chicken from the Islamic method. Minimizing residual blood in chicken meat or partial tissues and in preparing or retailing environments is important to prevent an increase of some pathogenic and spoilage bacteria.