Enhancing the shelf life of rainbow trout fillets using edible sodium caseinate coating with Oliveria decumbens essential oil nanoemulsion, vitamin E and sodium dodecyl sulfate.

Background: The use of essential oil nanoemulsions has emerged as a promising strategy for extending the shelf life of highly perishable foods, like fish, by leveraging their natural antimicrobial and antioxidant properties.

Aims: This study investigated the effects of an edible sodium caseinate coating incorporating Oliveria decumbens essential oil (Od-EO) and its nanoemulsion (Od-NEO), along with vitamin E and sodium dodecyl sulfate (SDS), on the shelf life of rainbow trout fillets during refrigeration.

Methods: Fish samples were coated by immersion in pure sodium caseinate (SC), SC+Od-EO, and SC+Od-NEO. Sensory (odor, color, texture, overall acceptance), chemical (pH, total volatile basic nitrogen [TVB-N], thiobarbituric acid [TBA], and peroxide value [PV]), and microbiological analyses (total mesophilic aerobic bacteria, psychrophilic anaerobic bacteria, and Pseudomonas spp. counts) were conducted over 15 days of storage at 4°C.

Results: The study results indicated that fillets treated with SC+Od-NEO exhibited significantly higher quality compared with other treatments. Additionally, the combination of nanoemulsion, vitamin E, and SDS showed synergistic effects in reducing microbial growth, delaying lipid oxidation, and improving organoleptic quality, extending the shelf life of rainbow trout fillets up to 15 days. Overall, the correlation analysis highlights the interdependence of microbial, chemical, and sensory parameters and reinforces the role of SC-NEO-based treatments in mitigating spoilage and maintaining the sensory quality of fish fillets during storage.

Conclusion: The results highlight the potential of nanoemulsion-based coatings as an innovative and effective strategy for extending the shelf life of highly perishable fish products. Coting with SC+Od-NEO+Vit E+SDS can be recommended as an effective food preservative.