Influence of sunflower oil based nanoemulsion (AUSN-4) on the shelf life and quality of Indo-Pacific king mackerel (Scomberomorus guttatus) steaks stored at 20 °C

The influence of nanoemulsion (AUSN-4) on the microbiological, proximal, chemical, and sensory qualities of Indo-Pacific king mackerel (Scomberomorus guttatus) steaks stored at 20 °C was studied for a time period of 72 h. AUSN-4 treatment showed initial reduction (P > 0.05) in the heterotrophic, H2S and lactic acid bacterial populations in 12 h, followed by a gradual increase in their respective populations. Irrespective of treatments, reduction in total carbohydrate, protein, and fat contents were observed in all samples with an increase in storage time (h), with AUSN-4 treated steaks having the lowest reduction. AUSN-4 treatment significantly (P < 0.05) decreased the values of chemical indicators of spoilage throughout the storage period. Organoleptic evaluation revealed that AUSN-4 treated steaks showed an extension of shelf life of 48 h, when compared with control and antibiotic treated samples, respectively. Based on the results obtained in our present study we conclude that sunflower oil based nanoemulsion preservative technique is able to extend the shelf life and maintain the quality of S. guttatus steaks during storage.