Effect of aqueous ozone on microbial and physicochemical quality of Nile tilapia processing

Abstract

The efficiency of ozonated water as a disinfectant for removing microorganisms in freshwater fish was investigated. Nile tilapia samples (whole and fillets) were immersed in cold water (11°C), without ozone (0 ppm—control) and with ozone (0.5, 1.0, 1.5 ppm) for 0, 5, 10, and 15 min. Microbiological and physicochemical parameters were evaluated. The most efficient ozone concentration to reduce microbiological contamination of the whole tilapia was 1.5 ppm (88.25% of reduction) at 15 min of contact. Ozonated water at 1 and 1.5 ppm showed the greatest reduction (77.2 and 79.49%, respectively) in the fillet treatment. Neither the pH nor the color of fillets was influenced by ozonated water treatment; however, a small triggering of lipid oxidation process was observed by the increase in the TBARS value. These results prove that ozonated water was effective in reducing the microbial load and maintain the quality of fish, with low cost. Practical applications As an environmentally friendly disinfectant, ozone now is being studied as an alternative to chlorine sanitizers in many segments of the food industry. The use of ozone as a superficial disinfectant of meat surfaces has been reported in the fish industry. Few studies on the use of ozone in farmed freshwater fish have been reported. Ozonated water treatments improve the quality and extend the shelf life of fish. We evaluated and proved the microbial efficiency of ozonated water during Nile tilapia processing, and indicate that fillet quality was not adversely affected by ozone treatment.

Dielectric barrier discharge cold atmospheric plasma: Bacterial inactivation mechanism

“…Oxidation of nucleic acids, lipid as well as amino acids was another possible mechanism (Fernández & Thompson, 2012). Among the reactive species generated during cold plasma, ozone (O 3 ), produced from the interaction of a molecular diatomic oxygen (O 2 ) with an oxygen atom, is regarded as the most active antibacterial agent (de Mendonça & Gonçalves, 2017;Pastoriza, Bernárdez, Sampedro, Cabo, & Herrera, 2008). However, factors such as treatment time (TT), contact time, working gas composition (WGC), voltage, frequency, and power determines the antibacterial efficacy of cold plasma as well as antifungal (Olatunde et al, 2019a).…”

Fish preservation: a multi-dimensional approach

“…In a study conducted by Mendonça et al, 31 treatment of whole fresh water tilapia with 1.5ppm ozonated water for 15min was sufficient to result in 88.25% reduction of initial microbial load. The same study also reported a reduction of 77.2% and 79.49% of microbial load in fillets of the same fish species treated with ozonated water at concentrations of 1 and 1.5ppm respectively.…”

Nonthermal Processes for Shelf‐Life Extension of Seafoods: A Revisit

“…The interaction of molecular diatomic oxygen (O 2 ) to an oxygen atom gives rise to ozone (O 3 ), which is a highly unstable triatomic oxygen molecule (De Mendonça Silva & Gonçalves, ). Ozone has been employed as an oxidizing agent in water treatment and in the food industry and is considered a powerful sanitizer (Blogoslawski & Stewart, ; Gonçalves, ).…”

“…Shelf‐life could be extended to 20 to 25 days when oysters were treated with ozone, whereas the control had a shelf‐life of 5 to 10 days. Microbial contamination in whole tilapia was reduced by 88.25% by treating the fish with 1.5 ppm ozone for 15 min (De Mendonça Silva & Gonçalves, ).…”