Ph.D. Dissertation:

Investigation on the Possibility Functional Doughnut Production by Using Antioxidants Extracted from Linume usitatissmum and Salvia leriifolia Seeds with Pre-treatment of Pulsed Electric Field

In the present study, the purpose of the first stage, comparison of antioxidant activity of aqueous and alcoholic extracts extracted from two sources of Salvia leriifolia and Linum usitalissmum under the influence of pulsed electric field with zero intensities (without pre-treatment), 3 and 6 kV / cm And the number of fixed pulses was 30. The parameters of total phenolic composition and antioxidant activity by DPPH and TEAC were investigated. The effect of plant source pre-treatment and solvent (aqueous and alcohol) in extracting the extract was significant on the antioxidant activity of the extracts. (P<0/05). By increasing the intensity of the precursor and selecting an alcoholic solvent, the antioxidant activity of the extracts is significantly increased at the 95% confidence level. The extract extracted from leriifolia with alcoholic solvent and pre-treatment (with an intensity of 6 kV / cm and a constant pulse number of 30) was selected as the extract with desirable antioxidant properties. In the second phase, concentrations of zero, 1, 2 and 3% of the best extract were added to the doughnut formulation and the physicochemical, tissue, visual, durability and sensory parameters of the product in three time periods (two hours, fourth and seventh day) compared to the sample was assessed. Increasing the level of consumption of leriifolia extract had no effect on moisture content, specific volume, porosity, product texture stiffness (in all three time periods) and sensory characteristics of the product. However, with increasing the amount of this extract, the amount of peroxide index decreased compared to the sample without the extract and the amount of phenolic compounds, antioxidant activity increased (in all three time periods). Finally, the sample containing 3% of leriifolia extract was selected as the best sample

Keywords: Alcoholic & aqueous extract, Salvia leriifolia, Linum usitalissmum, Pulsed Electric Field, Antioxidant activity, Functional Doughnut