Raw yellow or white onions contain flavonoids which have antioxidant and antimicrobial properties. This makes them a terrific alternative for preserving food. Onions inhibit the growth of micro-organisms that make food decompose and delay lipid oxidation in oil and water emulsions which means you should consider adding them to mayonnaises.
Onions effectively prevent the development of Bacillus cereus, Staphylococcus aureus, Micrococcus luteus and Listeria monocytogenes, microorganisms typically associated with the deterioration of foods.
On top of this, the onion flavonoids are good eating. They are antioxidant, anti-inflammatory, cardioprotective, vasodilatory and anti-carcinogenic.
Onions: The onion (Allium cepa) is one of the most cultivated and consumed vegetables on the planet (around 66 million tonnes in 2008, of which 1.1 million were produced in Spain, especially in Castilla-La Mancha), and one of the main ingredients of the Mediterranean diet.
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