Analysis of the inhibition of proteolytic microorganisms in red tilapia (Oreochromis spp) fillets preserved with propolis (Apis mellifera Linnaeus)

The food industry is focused on replacing chemical preservatives with organic alternatives for food preservation and safety. The present study seeks to analyze the use of propolis in the conservation of red tilapia fillets. Propolis was applied in two concentrations (15% and 30%) and two impregnation times (1.5 and 3 hours) to red tilapia fillets stored at 4-5°C for 30 days. Several parameters, including pH, water-holding capacity (WRC), and basic volatile nitrogen concentration (N-BVT), were evaluated at 10-day intervals. In addition, a microbiological analysis of mesophilic microorganisms and E. coli present was carried out. From day 20, significant differences were observed in the color of the fillet according to the chromatic coordinates L*, a* and b*. The sensory analysis showed that the sensory properties were maintained when the acceptance values were higher than 6.5. The most effective treatment was propolis in a concentration of 15% with a soaking time of 1.5 hours and preserved for 20 days. This approach showed that propolis effectively extends the shelf life of fillets by preventing proteolytic damage. In addition, it inhibits the proliferation of microorganisms by maintaining the load of mesophiles and E. coli, as well as the physicochemical parameters (pH, CRA and N-BVT) according to the NTE-INEN 183-2013 standard. In conclusion, propolis is a promising organic preservative for the food industry.