Effects of rosemary extract (Rosmarinus officinalis) on the stability of bread with an oil, garlic and parsley dressing

Rosemary extract (RE) at different concentrations (0, 2, 4 and 6 g/l) was added to a dressing consisting of sunflower oil, garlic and parsley. The dressing was then treated at 140 °C for 1 h to simulate the process of baking and was later stored in an oven for 10 days at 50 °C, to promote oxidation and to check the efficacy of the antioxidant in the RE. 2-Thiobarbituric acid (TBA) test and determination of peroxide value (PV) were performed every 2 days. The results obtained for PV revealed that from day 8 onwards the RE caused an antioxidant effect on the samples to which it had been added. The most efficient concentration was 0.4 g/l. Sensory tests performed on the bread with an oil and garlic/parsley dressing revealed no rancid taste during the initial 6 days of storage at 50 °C. No taste of RE was detected by a trained sensory panel at the two lowest concentrations added.