The addition of ascorbic acid improves the microbiological quality and shelf life of Atlantic mackerel (<i>Scomber scombrus</i>) fillets stored in ice

Abstract

Ascorbic acid is one of the most promising additives for improving fish shelf life, but studies on its antimicrobial activity during product storage are limited. In this experiment, we assessed the effect of ascorbic acid on the preservability of Atlantic mackerel (Scomber scombrus) fillets during storage in ice. Fillets were treated to reach an ascorbic acid concentration of 0.30 mg/g (T1) and 0.15 mg/g (T2). Samples were stored in ice at 0°C and analyzed at 0, 2, 7, 9, and 14 days for total viable count, specific spoilage organisms (SSOs), Pseudomonas spp., potentially histamine-producing bacteria (HPB), and Enterobacteriaceae. Growth curves were constructed using the DMfit tool of Combase, and the shelf life was estimated in relation to microbiological limits reported in the literature. Sensory evaluation was performed using a quality index method scheme. At 7 and 9 days of storage, treated samples exhibited bacterial counts from 0.5 to 1.7 Log CFU/g lower than controls, with a logarithmic reduction proportional to the additive concentration. The antimicrobial action appeared to diminish after 14 days. A consistent effect was observed for potentially HPB, with counts of 1.7 Log CFU/g lower in T1 samples compared to controls at 9 days. The moderate effect on SSOs limited the estimated shelf life, as the critical limit was reached after 7 days and 8.4 days (T1 and T2). Ascorbic acid positively impacted the microbiological characteristics of mackerel fillets. Further investigation into the decay dynamics of the additive in fish products during storage is advisable.

Keywords

• Ascorbic acid
• shelf life
• histamine
• fish
• food safety