M.A. Thesis:

Formulation of fanctional yogurt by Echinophora platyloba extract and evaluation of it's Antioxidant ٫ Reological and Physico-chemical propertic

Plant extracts that contain natural ingredients because medicinal properties, flavor and aromatic properties and antimicrobial effects are important in food industries. This extracts are widely used as spices, preservatives and antioxidants . In this study, Echinophora platyloba extract are used to enhance the diversity of formulations for produce of a functional yogurt . In this research work, effect of three concentrations of the platyloba extract respectively 0.02, 0.03 and 0.04 during the 19 days and the times of 1, 10 and 19 days were evaluated on physicochemical, antioxidant, phenolic compounds, sensory proerties, viscosity and color parameters of produced yogurt and changes was compared with a control sample. The results showed that with increasing of extract concentrations, antioxidant activity and phenolic compounds increased the rate but over time it increases to 10 and then are becoming declined to 19th day. Synersis value by increasing of time and concentration of the extract has a significant reducing . Both storage time and extract concentration had a significant effect on viscosity . Effect of Acidity had a significant increase during storage time and increasing of concentration (P <0.05). By increasing the storage time and concentration, pH Dropped significantly. Effect of storage time on the extract concentration on Color index was relatively significant, as concentrations of 0.03 and 10 th days, color index was in most level. b * and a * were lowest in concentran of 0.03. The sensory evaluation showed more acceptable concentration was 0.02

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