ANTIOXIDANT ACTIVITY OF THYME AND SAGE AND THEIR ANTIMICROBIAL IMPACT AGAINST Listeria monocytogenes AND Pseudomonas putida IN BEEF BURGER

The aim of this study was carried to evaluate the role of natural antioxidant and antimicrobial activity against Listeria monocytogenes and Pseudomonas putida from each thyme and sage powders as well as their ethanolic extracts in beef burger to help factories to extend the shelf-life of their products under storage at -18 C. Results revealed that by using 1.5 % of sage powder and 0.1% of ethanolic extract of thyme represented the optimum concentration for decreasing of Listeria monocytogenes count but the ethanolic extract of thyme at 0.1% gave the highest decreases in population of Pseudomonas putida in beef burger especially after 60 days of freezing storage condition. On the other hand, the results indicated that all treated samples with spices were recorded decreasing in thiobarbituric acid, peroxide and acid values compared with control sample. Moreover, moisture, protein and ash were decreased by increasing storage period. Meanwhile, only fat content was increased.