Thesis:

Studying the effect of Echium amoenum powder on the physicochemical, textural, and sensory properties of stirred yogurt during storage.

The aim of the present study is to add Echium vulgare plant powder to stirred yogurt and evaluate the physicochemical, textural and sensory properties of yogurt during storage. For this purpose, plant powder was added to yogurt at three levels of 0.5, 1 and 1.5% w/w after incubation and packaging was performed again and all tests were performed on days 1, 11 and 22 of storage at refrigerator temperature. The results indicated that all treatments studied in this study had a significant decrease in the trend of pH changes and an increase in acidity; it was also determined that the time and amount of Echium vulgare plant powder used in all treatments had a significant effect on pH and acidity during storage at the level studied (p?0.05). With increasing Echium vulgare plant level, moisture content increased and dry matter decreased, and the highest amount belonged to the sample containing 1.5% plant powder. While during the storage period, moisture content decreased and dry matter increased. The results showed that the addition of borage plant powder reduced the amount of syneresis and the lowest was in the sample containing 1.5% plant powder. The results of texture analysis indicated that with increasing the percentage of Echium vulgare plant powder, the amount of firmness, cohesion, gumminess, and the amount of tissue adhesion force increased and increased during the storage period. Among the samples studied, the control sample obtained the highest score in terms of taste, but in terms of other sensory indicators, the sample containing 1.5% Echium vulgare plant powder obtained the highest sensory evaluation score.

Keywords: Echium vulgare plant powder, functional compounds, stirred yogurt, physicochemical and textural prop