Olive extracts may slow spoilage of meats

The olive extract, obtained from the waste waters of olive oil pomace, performed better than a commercial antioxidant sourced from wine, according to findings published in the journal Food Chemistry​

“The polyphenol extract from the waste water of olive oil’s pomace significantly inhibited lipid oxidation in pre-cooked ground beef and pork. The antioxidant effect increased with the dose and was higher in beef than in pork,”​ wrote Sharon DeJong from Food Science Australia and Maria Cecilia Lanari from Argentina’s National Council for Scientific and Technical Investigation (CONICET).

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.

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.

The research taps into this trend, and found that hydroxy-tyrosol, caffeic acid and oleuropein were amongst the highest contributors to the antioxidant activity of the olive extract.

Tests were performed in both pre-cooked beef and pork, and the crude polyphenol extracts were added at a dose of either 50 or 100 mg gallic acid equivalents (GAE)/kg meat. Using the thiobarbituric acid-reactive substances (TBARS) assay to measure the degree of lipid oxidation, DeJong and Lanari report that that the olive extract reduced TBARS formation by between 63 and 83 per cent in the beef, and by between 47 and 66 per cent in the pork.

When compared to commercially available tea and wine extracts, the best performance was observed for tea, while the wine extract performed the least effectively.

The commercial wine extract was prepared by aqueous extraction of red grape (Vitis vinifera) skin, while the green tea extract was Polyphenon 30, manufactured by Mitsui Norin Ltd., Japan.

Source: Food Chemistry​Volume 116, Issue 4, Pages 892-897“Extracts of olive polyphenols improve lipid stability in cooked beef and pork: Contribution of individual phenolics to the antioxidant activity of the extract”​Authors: S. DeJong, M.C. Lanari