Production of fortified stirred-yogurt containing allium iranicum powder and evaluation of its shelf-life, physicochemical and sensory properties

In this study, the effects of Allium iranicum adding to yogurt were studied to improve the quality and shelf-life of the product. Allium iranicum powder was used in 3 levels of 0.5 %, 1.25% and 2% in the production of stirred yogurt. Two quantitative factors such as concentration of Allium iranicum powder and storage time were investigated using a growing factorial design with central points. After collecting data, analysis of variance and linear regression were used to investigate the effects of factors and their significance. After data modeling, the effects of powder percent and storage time on physicochemical properties (pH, acidity, WHC, antioxidant property, synergistic, dry matter, viscosity, color properties and sensory properties) were investigated. The results showed that with increasing the percent of Allium iranicum powder, the acidity of the samples increased during storage and the dry matter increased with increasing the concentration of Allium iranicum powder. Viscosity, WHC, synergy and sensory and colorimetric properties were desirable in lower levels of Allium iranicum powder. Antioxidant activity increased with increasing powder percent and decreased during storage time. The highest total acceptance of yoghurt samples was for samples containing powder (1.25%) and 2% showed a negative effect on sensory function. According to the results, it was found that the Allium iranicum powder at 1/25% level could improve the properties and durability of yogurt samples.   [1] Water Holding Capacity