Enhancing shelf life of refrigerated salmon: Synergistic roles of glutaric and azelaic acid with conventional preservatives

Glutaric acid (GA) and azelaic acid (AA) are emerging antibacterial agents with the potential to partially replace conventional preservatives in food systems. This study is the first to evaluate the preservative efficacy of triple combinations, GA–sodium bisulfite (SB)–AA (2:8:1) and GA–sorbic acid (SA)–AA (2:2:1), for improving the storage quality of sliced and minced salmon during a 12-day refrigerated storage period at 4 °C. In vitro screening revealed synergistic antimicrobial activity of both combinations against Salmonella enterica, Escherichia coli, Streptococcus pyogenes, Bacillus cereus, and Candida albicans (ΣFIC = 0.063–0.438). Notably, GA–SB–AA exhibited enhanced antioxidant properties. When applied to salmon products, the selected combinations significantly reduced microbial load, minimized weight loss, retained color, and decelerated increases in spoilage indicators, including pH, total volatile base nitrogen (TVB-N), peroxide value (POV), and thiobarbituric acid (TBA) levels. These preservative effects were dose-dependent. Beyond functional efficacy, this approach aligns with clean-label trends and regulatory initiatives aimed at reducing the use of synthetic preservatives, such as SB and SA. Notably, it offers substantial cost advantages: while AA and GA are relatively expensive, the optimized combinations predominantly rely on lower-cost components such as SB and SA, resulting in a cost-effective formulation with comparable or superior preservation outcomes.