Investigation of the Combined Effect of Ozonated Water and Chitosan on the Shelf Life of Tilapia ( Oreochromis spp.)

ABSTRACT

Fresh fish is highly perishable due to microbial spoilage, autolytic degradation, and lipid oxidation, resulting in a limited shelf life. This study investigated the effects of ozonated water (2 ppm, 2 min), chitosan coating (1% w/v ), and their combination on the quality of tilapia ( Oreochromis spp.) stored at 4°C for 10 days. Texture, pH, total volatile base nitrogen (TVB‐N), and total plate count were evaluated to assess efficacy in preserving the shelf life of tilapia. Ozonated water showed the lowest TVB‐N on Day 10 (15.05 ± 0.70 mg/100 g), significantly lower than chitosan (18.55 ± 2.65 mg/100 g) and ozonated water + chitosan (19.60 ± 2.80 mg/100 g) ( p  < 0.05), indicating its effectiveness in preserving fish freshness and delaying spoilage. The ozonated water group consistently exhibited the lowest total microbial load throughout storage (2.36 ± 2.057 to 6.93 ± 0.060 log CFU/mL). Overall, these findings suggest that ozonated water treatment may contribute to improved quality preservation and potential shelf‐life extension of tilapia.