چكيده انگليسي :
As regards to growing demand for vegetable oils, it is essential to find new plant sources that have good nutritional and therapeutic properties. Therefore, in this study, we tried to find a new plant source for oil production. One of these new sources is oak fruit, which is includes more than 500 species of plants, most of which are native to the Mediterranean region, and in Iran, more than 70% of the plant types of Zagros forests are oak. Oak oil has a high nutritional potential and is a good source of essential fatty acids such as oleic, linoleic and linolenic acids. Also, the high amount of tocopherols has made this oil more valuable. In this study, the optimization of extraction efficiency was investigated by Soxhlet apparatus and the physical and chemical characteristics of the extracted oil including: refractive index, specific gravity, color, acid number, peroxide number, soap number, iodine number, fatty acid profile, tocopherols and Sterols were measured. Finally, the oil refining process took place. 3 time levels (6, 8 and 10 hours) and 3 levels of sample to solvent ratio (1: 8, 1:14 and 1:20) were used to optimize the extraction, and the percentage of efficiency, acidity and peroxide number as the design response in Was considered. Optimal conditions with a time of 7.25 hours, sample to solvent ratio of 14.86%, efficiency of 7.60%, free fatty acids (in terms of oleic) were 2.34% and peroxide number was 6.32. The amount of ash, moisture, protein, fiber and fat of oak fruit were measured as 1.72, 9.59, 05.05, 1.35 and 8.3%, respectively. By examining the physical and chemical parameters of the oil extracted with Soxhlet and the control sample, there was a difference between acid number, soap number, peroxide number and L and a indices in oil color. The indices of acid number, soap number and peroxide number in Soxhlet sample were higher than the control sample, the main reason being the use of temperature in the oil extraction process. The L-index in the Soxle sample was higher than the control sample because the sample was not in direct contact with the solvent, but the A-sample in the control sample was longer than the Soxele sample, because more time was spent in the control sample and more pigments were removed. Became lawful. The values of iodine number were 80.6 mg of iodine per 100 g of oil, soap number of 190.52 mg of profit per gram of oil, refractive index of 1.4684 and specific gravity were determined to be 0.9129. Finally, the purification process reduced free fatty acids to 0.26%, peroxide number to 0.77% and reduced tocopherol and sterol compounds. However, the amount of tocopherol compounds in the oil after the refining process is sufficient for the antioxidant activity in the oil.
