Evaluation of quality and safety of beef hamburgers fortified with Ozonated Extra Virgin Olive Oil

This study investigates the impact of Ozonated Extra Virgin Olive Oil (OEVO) on the shelf life and quality of beef hamburgers during a 15-day storage period. Firstly, the Extra Virgin Olive Oil (EVO) was ozonated, and its oxidative stability and Fatty Acid Profile (FAP) were evaluated before and after ozonation. The oxidative stability of EVO decreased insignificantly (p > 0.05) after ozonation with a 3.54% Reduction in Induction Period (RIP). However, ozonation significantly increased (p < 0.05) the oleic acid and lignoceric acid contents. Then, the EVO and the produced OEVO were used to formulate two hamburgers. A conventional hamburger was also prepared as the control sample. The quality and safety of the prepared hamburgers were analyzed using TBARS, colorimetric, and microbiological assays. The TBARS index was extremely low, ranging from 0.049 to 0.270 mg MDA/kg hamburgers. There was no significant difference (p > 0.05) between the redness (a* value) of hamburgers on different days, excluding days 7, 13, and 15. The combined properties of EVO and ozone had a prominent antimicrobial effect, increasing the shelf life of the beef hamburgers by reducing the number of Total Viable Count (TVC), Lactic Acid Bacteria (LAB), Enterobacteriaceae (EB), and Coliforms (CF).