Vliv přírodních extraktů na senzorické vlastnosti a prodloužení skladovatelnosti masa pstruha duhového (Oncorhynchus mykiss)

This bachelor thesis evaluates the effects of natural rosemary extract "Inolens 4" on microbiological quality, sensory attributes, colour change and oxidative effect of rainbow trout (Oncorhynchus mykiss). The evaluation is expressed in comparison with the control sample (no additive). Individual analyses took place in different days (0, 3, 6, 10 and 14 days). The microbiological analysis showed values in the range of 1.93 - 2.25; 5.10 - 5.27; 5.12 - 5.80 and 6.34 - 7.66 log CFU*g-1 on days 0, 6, 8 and 10. The limit for freshwater fish consumption (7 log CFU*g-1) was exceeded on 10th day of storage. On the contrary Inolens 0.5 achieved the best result. Sensory analyses also showed that Inolens 0.5 achieved the best results in all sensory attributes (odour, taste, aftertaste, consistency) of cooked fish. Also TBARS analysis evaluating lipid oxidation proved that the application of Inolens 4 extract had a positive effect causing an inhibition of oxidative processes in the muscle. Therefore all the results of this study have shown that the natural extract "Inolens 4" has antioxidant effects extending the storage of rainbow trout meat in combination with suitable storage (vacuum and cooling at 4 +- 1 °C) for up to 10 days. Moreover it has a mild effect on the improvement of sensory properties