Ground beef microbiome changes with antimicrobial decontamination interventions and product storage.

Area of Science:

• Food Microbiology
• Microbial Ecology
• Genomics

Background:

• Ground beef is a major U.S. meat product, with existing research focusing on microbial safety and shelf-life, often using culture-dependent methods.
• Limited studies have explored the complete microbial community of fresh ground beef using culture-independent approaches.
• Understanding the fresh ground beef microbiome is crucial for ensuring food safety and quality.

Purpose of the Study:

• To characterize the fresh ground beef microbiome using 16S rRNA gene amplicon sequencing.
• To investigate the effects of antimicrobial interventions and antioxidants on microbial community composition.
• To assess the impact of product storage duration and conditions on the ground beef microbiome.

Main Methods:

• Utilized 16S rRNA gene amplicon sequencing on 52 selected samples from a larger study.
• Applied antimicrobial treatments (peroxyacetic acid, sulfuric acid/sodium sulfate blend) and an antioxidant to beef trimmings before grinding.
• Stored samples in modified-atmosphere packaging, including dark storage and retail display, with periodic microbiological analysis.

Main Results:

• Antimicrobial treatments significantly altered bacterial alpha and beta diversity (P < 0.001).
• Storage duration impacted alpha diversity (P = 0.001), with increased raw reads and aerobic plate counts over time.
• Lactic acid bacteria and Enterobacteriaceae were dominant; rare taxa like Geobacillus, Thermus, and Sporosarcina were identified. Enterobacteriaceae abundance was highest in control samples.

Conclusions:

• Culture-independent 16S rRNA sequencing provides a comprehensive understanding of the fresh ground beef microbiome.
• Antimicrobial interventions and storage conditions are key drivers of microbial community structure in ground beef.
• This approach identified previously unrecognized microbial genera, enhancing insights into ground beef microbial ecology beyond traditional methods.