Volatile oils are natural products with high antioxidant activity but their chemical composition and antioxidant activities may change due to the thermal storage conditions. In the present study, the changes in antioxidant activity and thermal stability of bay laurel, lemon peel, and orange peel essential oils stored at refrigerator temperature (4°C), room temperature (20°C), and elevated temperature (37°C) for 12 months were examined. In the determination of antiradical activity measured using DPPH method at the beginning of storage, the bay laurel essential oil (82.82%) showed a better inhibition percentage when compared to lemon (32.30%) and orange (46.52%) peel oils. During the storage, a decrease was observed in the antioxidant and antiradical activity values of the oils. The aromatic compositions of volatile oils were determined using GC/MS and the main components of volatile oils were found to be 1,8 Cineolene (50.4%) for bay laurel, d-limonene (80.1%) for lemon peel, and d-limonene (94.6%) for orange peel. At the end of this study, it was found that the change in the compositions of essential oil samples stored in the refrigerator was at a lower level, whereas significant changes were observed in both volatile compositions and antioxidant activity values of the samples stored at elevated temperatures. Moreover, it was also observed that the volatile oils obtained might form natural potential agents that can be used as antioxidant in food products.

The present study aims to develop gluten-free product formulations by using different seed flours to determine their effectiveness in gluten-free products. For this purpose, a baton cake model was selected; the cake production process was conducted by adding hemp, okra, mustard, or coriander seed flours with rice flour at a ratio of 25% seed flour to 75% rice flour to prepare the cake batters. The physicochemical, textural, and sensory properties, as well as the baking behaviors of the resulting products, were determined. The TOPSIS method was used in the sensory analyses. With the addition of seed flours, a color change occurred in the inner and crust values of the baton cake samples. It was observed that the hardness value of the baton cake samples increased with the addition of seed flour. In the TOPSIS evaluation, which is a multi-criteria decision-making method, the most preferred product in the free baton cake samples was the cake with hemp seed flour added, while the least preferred product was the control group baton cake. According to the findings, it was concluded that the use of seed flours can be used as an alternative ingredient in the production of gluten-free baton cakes that celiac patients can consume in their diets.