عنوان مقاله [English]
In this study, the effect of adding ginger (Zingiber officinale) essential oil (500 ppm and 1000 ppm) and storage time (1, 7, 14, and 21 days) on the physicochemical, microbial and sensory properties of yogurt was investigated. The results showed that the amount of ginger essential oil had a significant effect on acidity, synersis and the total population of mold and yeast (p < 0.05). As the amount of ginger essential oil increased, the synersis and the amount of mold and yeast decreased significantly, but the amount of ginger essential oil did not have a significant effect on the dry matter (p < 0.05). Storage time also had a significant effect on all measurement factors except acidity (p < 0.05). Over time, the amount of synersis and mold and yeast population in the control sample and treatment containing 500 ppm of essential oil increased and the pH decreased, but in the sample of yogurt containing 1000 ppm of ginger essential oil, no mold and yeast was observed until the last day of storage also pH remained constant during storage. The results of statistical analysis of sensory evaluation of yogurt samples also showed that with increasing the amount of ginger essential oil, the tissue score did not change significantly, but with increasing the amount of essential oil, the flavor and overall acceptance index increased (p < 0.05).The results show that adding ginger essential oil increases the shelf life of yogurt and improves yogurt sensory properties.