Changes in the microbial communities of air- and water-chilled yellow-feathered broilers during storage at 2 °C

Carcass chilling is a critical step in broiler processing. Understanding the effect of chilling on the bacterial communities of broilers is important, as these communities may be largely responsible for the spoilage process. This study examined the effect of chilling systems (air chilling [AC] and water chilling [WC]) and subsequent aerobic storage on the microbiota of yellow-feathered broiler carcasses using a high-throughput sequencing technique targeting the V3-V4 region of the 16S RNA gene. Evidence of the clear differences in the microbiota structures between AC and WC carcasses was illustrated by principle coordinates and heat map clustered analyses. The distinctions between the AC and WC carcass bacterial communities were more pronounced during the later storage stages. The major genera on the spoiled AC carcasses were Pseudomonas, Psychrobacter and Shewanella, whereas the major genera on the spoiled WC carcasses were Psychrobacter, Pseudomonas and Carnobacterium. These data suggest that the chilling method has a marked effect on the microbiota composition of yellow-feathered broilers along the entire storage period. The chilling method was also of great importance for surface color. However, there was no significant difference in the sensorial shelf-life of chicken when comparing the chilling methods.