Influence of rosemary extract (Rosmarinus officinalis) Inolens to extend the shelf life of vacuum-packed rainbow trout (Oncorhynchus mykiss) fillets stored under refrigerated conditions

The effects of three concentrations (0.5, 1.0 and 2%) of rosemary extract Inolens 4 and control (without additive) on microbiological quality, sensory attributes, colour parameters and oxidative stability of rainbow trout (Oncorhynchus mykiss) fillets during refrigerated storage after different periods (0, 3, 6, 10 and 14 days) were investigated. Microbial communities grew to between 1.93 and 2.29 colony-forming units per gramme (log CFU g(-1)), 5.10 and 5.27, 5.12 and 5.80 and 6.34 and 7.66 log CFU g(-1) after 0, 6, 8 and 10 days of storage, respectively, and fillets treated with Inolens 0.5 showed the lowest total viable counts among all analysed groups. Also, sensory analyses showed that Inolens 0.5 achieved best scores in all sensory attributes of cooked flesh. Evaluation of lipid oxidation parameters proved that treatment with Inolens 4 had a positive effect, leading to delay oxidation processes in flesh.