Evaluation of antioxidant and antimicrobial effects of Thymus vulgaris essential oil on cream cheese

Cheese is a dairy product that is susceptible to contamination by pathogenic and spoilage microorganisms. Microbial contamination can reduce its shelf life and Cause serious health risks to consumers. Thymus vulgaris essential oil has high antioxidant and antimicrobial activity and can improve and enhance the storage time of food systems. In order to evaluate the effect of thymus vulgaris essential oil on physicochemical, microbial and sensory properties of cream cheese, different percentages of thymus essential oil (0, 0.005, 0.01% and 0.015%) were added to cream cheese. Cheese sample were analyzed in the first, fourth and seventh weeks of storage. The results showed that Changes in essential oil percentage had significant effect (P<0.05) on acidity, dry matter, adhesiveness, IC50 and peroxide. With increasing essential oil percentage, a decrease in the level of acidity, adhesiveness, peroxide and IC50 was observed. Changes in essential oil percentage had no significant effect (P<0.05) on pH, fat, hardness and protein content of cheese. The results showed that storage period had a significant effect (p<0.05) on acidity, pH, dry matter, IC50, peroxide, adhesiveness, but had no significant effect (P<0.05) on protein, fat and hardness. During the storage time, Acidity, dry matter, protein and IC50 increased and pH and adhesiveness decreased. The addition of thymus essential oil did not have a significant effect (P<0.05) on coliforms but significantly decreased (P<0.05) mold and yeast and total count. The results showed that the addition of essential oil to cheese did not have a significant effect on color and texture but had a significant effect on taste and acceptance of cheese and improved the taste and acceptance. High percentage of essential oils reduced the sensory characteristics of cheese. In general, the treatment containing 0.005% essential oil was the best treatment for the sensory properties.