Affordable Novel Alternative Methods for the Enumeration of Lactic Acid Bacteria in Vacuum Packed Fishes

This study proposes two alternative new methods for enumerating lactic acid bacteria: sodium bicarbonate-acetic acid with palladium catalyst (SBC-AA-PC) and vacuum petri dish (VPD). Both were evaluated for cost-effectiveness, time, and efficiency by enumerating Lactobacillus sp. in vacuum-packed Euthynnus affinis (Tuna). Results obtained in these methods were compared to the Anerogas pack (AGP) method and carbon dioxide incubatior (COI) method. No significant difference in bacterial count was found among the four methods (p > 0.05). Considering both investment and consumable expenses, the new methods reduce total costs by about $1,740–$1,782 compared to previous methods. These methods are functionally suitable for routine monitoring of facultatively anaerobic or microaerophilic bacteria reflecting fish spoilage under reduced atmosphere packaging.