Investigation the effect of Dill extract (Anethume graveolens) using on the Antioxidant and Physicochemial properties of Set Yogurt

In present study dill extract was used in yoghurt in order to increase its consumption acceptability and promote its functional properties. So, the dill extract in (0, 5 and 10%) concentration was added to the milk that used to prepare yoghurt and its pH, acidity, total phenolic compounds, DPPH inhibition percentage, viscosity, synersis, water holding capacity, colour evaluation, and sensory properties were investigated after 1st, 7th, 14th and 21th day of production. Investigation of the results showed that with increase of the extract amount, inhibition percentage and phenolic compounds amount increased, significantly (P<0.01), The effect of storage time was also significant on the indexes, in a way that antioxidant properties and phenolic compounds increased in all treatments until 7th day and then it decreased. The effect of treatment type was significant on some physicochemical characteristics (such as pH, acidity, viscosity, synersis and water holding capability) of the yoghurt with dill extract (P<0.01). Throughout storage time, acidity level and pH increased significantly in all yoghurts and synersis and viscosity decreased. The results of color evaluation indicated that addition of dill extract reduced red spectrum (a*) and lightness (L*) and increased yellow spectrum (b*). In sensory evaluation, the highest score was given to the yoghurt with 5% of dill extract.