The effect alginate nanoparticles containing essential oils edible coating on the reduction of aerobic mesophilic bacteria in shrimp

Aim and Background: Postponing the deterioration of seafood quality is one of the most important challenges in recent years. The main objective of this study was to investigate the growth of aerobic mesophilic bacteria in shrimp coated with sodium alginate nanoparticles containing Zataria multiflora and Cuminum cyminum essential oils (EOs) during storage in the refrigerator. Methods: Nanoparticles were prepared by ionic gelation method and characterized using DLS. Also, DPPH test was used to check the antioxidant properties of nanoparticles. Shrimp samples were classified into three different categories, including (a) uncoated sample, (b) sample treatment with nanoparticles alginate coating, and (c) sample treatment with alginate nanoparticles containing Z. multiflora and C. cyminum EOs. Microbiological analyses were performed at 3-day intervals to determine the quality of coated shrimp samples. Results and discussion: the results showed that at the end of the storage period (15 days of storage at 4 °C), The number of aerobic mesophilic bacteria in treatment c was 2.85 Log CFU/ml, While in treatment a and b, it was 3.52 and 3.20 Log CFU/ml, respectively. These findings can be the result of delaying the microbial activity by nanoparticles and EOs. Conclusion: The coating of sodium alginate nanoparticles containing Z. multiflora and C. cyminum EOs can reduce the growth of aerobic mesophilic bacteria in shrimp during refrigerated storage.