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This study was conducted to assess the antibacterial efficacy of Artemisia persica Boiss essential oil (APBEO) at a concentration of 75 and 150 ppm with probiotic bacterium Lactobacillus paracasei in preserving the microbial and organoleptic quality of Doogh during storage at 4°C. The results indicated a gradual increase in acidity, whereas a decline in pH was noted in all the samples (p < .05). The addition of APBEO (150 ppm) and probiotics in doogh exhibited a synergistic effect and increased death rate of L. monocytogenes and E. coli O157: H7 in Doogh samples after 15 days. Also, the high score of overall acceptability was associated with the sample with 75 ppm APBEO. The incorporation of APBEO and probiotics in the sample exhibited a synergistic trend to ensure the safety of doogh and keep the quality of products. Highlights• The addition of Artemisia persica Boiss essential oil and probiotics in Doogh exhibited a synergistic effect.• The acidity increased significantly of Doogh, while the pH decreased significantly in all the samples.• The high score of overall acceptability was associated with the sample with 75 ppm Artemisia persica Boiss essential oil. | INTRODUC TI ONRecently, the interest in fermented dairy products has increased worldwide due to their specific organoleptic properties, extended shelf life, and the health-promoting potential. Doogh as a fermented product is the most commonly consumed Iranian yogurt drink which is usually prepared by mixing water, salt, and yogurt, and acidified by fermentative bacteria including Streptococcus thermophilus and Lactobacillus delbrueckii ssp. Bulgaricus (Sasanian et al., 2018).Dairy products, including Doogh, are frequently associated with the presence of E. coli O157: H7 and L. monocytogenes, two of the most important food-borne bacterial pathogens, which are considered a serious threat to the safety of fermented milk (Al-Nabulsi et al., 2016). The ability of these pathogens to survive and grow under various adverse environmental conditions, including low pH and high salt concentration, makes them potential hazards after the consumption of milk and dairy products (Cataldo et al., 2007).Chemical additives are commonly used to prevent spoilage or growth of pathogenic microorganisms, but their toxigenic residuals and impact on human health are under discussion. So, naturally occurring antimicrobials especially plant essential oils (EOs) have gained attention among researchers and food manufacturers due to their safety and preservative effects (Saeed et al., 2019). Among these, Artemisia persica Boiss with the local name of "Dermaneh" grows abundantly in the West, Central, North East, and South East of Iran. It is a medicinal plant that is a subject of considerable attention due to its biological and chemical diversity, and essential oil production. The leaves have high levels of diterpenes, such as Totarol, which have cytotoxic effects on bacteria and can stimulate the secretion of ɑ-interferons (Kalemba et al., 2002).

Lipid and protein oxidation are important reactions in food systems and can degrade food quality and decrease consumer acceptability. Several factors affect the rate and severity of these undesirable reactions in food products. However, lipid and protein oxidations can occur in the digestive system, which is much more complex than in simple food systems. Under digestive conditions, food matrix and composition are the major factors affecting lipid and protein oxidations in the body. Lipid and protein oxidation in food matrixes or the digestive system, as well as product absorption rate, can have serious consequences for human health. This review aimed to present recent information and discussion on the effects of digestion conditions and natural and synthetic antioxidants on lipid and protein oxidation.