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Olive Oil Acidity

What is olive oil acidity? 

One way the olive oil industry measures the quality of an oil is through its free acidity levels. Olive oil is made up of triglycerides which are groups of three fatty acids connected to a glycerol backbone. Fatty acids in fresh, high quality olive oil are chemically bound to the glycerol. This chemical bond is broken in oil made from diseased or bruised fruit or when there are delays in milling, exposure to high temperatures, or poor storage conditions. In other words, the fatty acids become free of the glycerol backbone. The acidity test measures the percentage of free fatty acid content in the oil. In general, the better the oil – the lower the acidity. All COOC certified EVOO will have a free acidity level less than 0.5%.