Oregano oil extends shelf life, but causes off-flavors
February 3, 2010
MISSISSIPPI STATE, MISS. — Results of a study that appeared on-line Jan. 29 in the Journal of Food Science indicated oregano oil may reduce lipid oxidation and extend the shelf life of meat products, but further investigation would be needed to avoid off-flavor and acceptance of product quality.
The study involved researchers from Mississippi State University and the University of Kentucky in Lexington. They used beef longissimus dorsi and semimembranosus mucles from animals of various ages, including 18 months, 30 to 60 months, and greater than 60 months.
The researchers halved six muscles of each age group and enhanced them with either a control brine containing no antioxidants or a brine containing oregano oil. The meat pieces then were cut into steaks and stored in modified-atmosphere packaging for 0 days, 4 days, 7 days and 11 days. Each sampling day the researchers measured surface color, lipid oxidation, cook yield, sensory analysis and Warner-Bratzler shear force.
The steaks enhanced with oregano oil decreased lipid oxidation but had no effect on Warner-Bratzler shear force or sensory tenderness and juiciness scores when compared to the steaks that had no antioxidants. The steaks enhanced with oregano oil had less rancidity detection, more off-flavor and lower overall acceptability in sensory analysis.
“Our research indicated that although oregano oil did reduce lipid oxidation, the adverse effects of flavor were too great and thus would not be tolerable in fresh meat products at this concentration,” the researchers wrote. “However, there is potential to use oregano oil at lower concentrations and in a variety of processed products which could be beneficial to further the use of natural antioxidants.”