Phenol and polyphenol compounds are common to all olives. Some of these phenol compounds contribute to the color of the olive. Others have antimicrobial activity against a wide variety of microorganisms (including lactic acid bacteria).The phenol fraction of olives (and olive oil) also may have positive dietary and nutritional benefits, due to their antioxi-dant activities (Box 7-5). The most important and abundant phenol is oleuropein (part of a class of compounds called secoiridoids).
Structurally, oleuropein is a glucoside ester of 3,4-dihydroxytyrosol and elenic acid (Figure
7-6). Glucosidic phenols, and oleuropein in particular, are important in olives owing to the pronounced bitter flavor they impart. Some olive varieties can contain as much as 14% oleuropein (on a dry basis) during the early stages of growth, although most contain no more than 3% to 6%.As the olives mature, the oleuropein concentration decreases, and at maturation, about 1 mg to 2 mg per g of pulp is present. Still, between the remaining oleu-ropein and related derivatives, the olives are too bitter to consume. Thus, manufacturing processes for most olives, including some fermented varieties, include sodium hydroxide-treatment steps to remove the bitter oleu-ropein fractions.
Olives, of course contain a significant amount of oil (12% to 30%, depending on cultivar).The fermentable carbohydrate concentration of ripe olives generally ranges from 2% to 5%; most of this carbohydrate is glucose. However, when the olives are washed or treated to remove the bitter components, sugars are also lost.
Was this article helpful?
You may be forgiven for thinking that these passed down secrets had gone for good, washed away with time and the modern age, But they're not. You can now own three of the best traditional did you know style reports that were much loved by our parents and grandparents. And they were pretty smart too because not only will these reports save you time and money but they'll also help you eliminate some of the scourges of modern day living such as harmful chemical usage in the home.