Researchers from the University of Kentucky and Mississippi State University report that oxidation of the fat content of the meat was significantly reduced by addition of the oregano oil, but the pereption of off-flavours was increased, showing that more work is needed to perfect the use of oregano oil in such formulations.
The authors, led by Stacy Scramlin, report their findings in the Journal of Food Science.
“Decreases in meat consumption have led the meat industry to become more innovative in product development,” explained the authors, led by. “Reducing lipid oxidation is a viable method to reduce rancidity, and improving product acceptability.
“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,” they added. “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.”
Oxidation processes in food can lead to organoleptic deterioration in taste, colour and texture. The food industry has long been aware of this, and is increasingly seeking natural solutions rather than artificial additives, such as like butylhydroxyanisole (BHA) and butylhydroxytoluene (BHT), to extend the shelf life of milder-tasting products.
Using meats of animals of various ages, ranging from 18 up to 60 months, Scramlin and her co-workers tested the effects of a brine containing oregano oil (0.5 per cent) to reduce lipid oxidation and affect palatability of the resulting meat product after 4,7 and 11 days of storage.
Results showed that lipid oxidation, measured using the thiobarbituric acid-reactive substances (TBARS) assay, decreased in all the samples. The oregano oil was also associated with a decline in the rate of colour change of the meat, added the researchers.
On the flip side, an increase in off-flavours was detected, and tasting tests showed a lower overall acceptability of the meat.
“This indicated oregano oil can effectively reduce lipid oxidation and extend shelf-life of meat products, but further investigation would be needed to avoid off-flavor and acceptability of product quality,” concluded the researchers.
According to a 2003 report by Frost and Sullivan, the synthetic antioxidant market is in decline, while natural antioxidants, such as herb extracts, tocopherols (vitamin E) and ascorbates (vitamin C) are growing, pushed by consumer desire acceptance and easier market access.
Source: Journal of Food Science
Published online ahead of print, doi: 10.1111/j.1750-3841.2009.01459.x
“Effects of Oregano Oil Brine Enhancement on Quality Attributes of Beef Longissimus dorsi and Semimembranosus Muscles from Various Age Animals”
Authors: S.M. Scramlin, M.C. Newman, R.B. Cox, H.A. Sepe, A.L. Alderton, J. O'Leary, W.B. Mikel