The Effect of Different Concentrations and Storages Time of Thyme and Rosemary Essential Oils on Qualitative Properties of Button Mushroom

Button mushroom gets rotten rapidly immediately after harvest and its color changes, due to lack of cuticle, high respiration rate, high humidity, and severe enzymatic activity. The aim of this study was to investigate the effect of essential oils of thyme and rosemary herbs on some qualitative characteristics of the button mushroom.
This research was conducted in a completely randomized design with the aim of evaluating the effects of concentrations of 0, 2.5, 5.0, 7.5, and 10.0 μl/l of rosemary and thyme, and storage duration of 0, 5, 10, 15, and 20 days on the qualitative properties of the button mushroom including tissue stiffness, moisture of the fruiting body, browning index, and antioxidant capacity.
Findings: With increasing the storage time, the moisture and texture stiffness decreased compared to those in control treatment. Evaluating the essential oil concentration, it was observed that the highest moisture content was obtained in the concentrations of 0 and 5.0 μl/l in 13.5% and 13% of essential oils, respectively; and the highest stiffness was obtained at concentrations of 7.5, 5.0, 10.0, and 2.5 μl/l of thyme essential oil as 10.95%, 10.52%, 9.90%, and 9.87%, respectively. The highest rate of antioxidants was observed at 0, 5 and 10 days in the range of 60%-75%. Moreover, increasing the storage time compared to the day of zero, a significant increase was found in the browning index.
Using the essential oils based on the type, concentration, and storage time of the product showed different results on the qualitative properties of the button mushrooms; the suitable concentrations can be selected based on the objective. According to the results, it seems that the concentration of 5 μl/l of thyme essential oil is a suitable treatment to maintain the qualitative properties of the fruiting body of button mushroom during the storage period.