Indicates the percentage expressed in oleic acid in an oil and it is a quality indicator. As the value increases, the quality of the product decreases. It can also increase due to negligence in the production process: use of overripe or unhealthy olives, excessively long time intervals between the collection and processing of olives, poor care or hygiene in processing.
The acidity can not be found in the taste of the oil but it is definable only through laboratory analysis. Extra virgin olive oil must have maximum acidity, expressed as oleic acid, 0.8% .
Bitter and spicy span
The bitter and spicy taste that is felt in the tasting of extra virgin olive oil is determined by particular polyphenols (hydroxytyrosol) whose presence, besides certain values, characterizes a product high quality natural as required by EC Regulation 432/12.
The storage of an extra virgin olive oil is very important to keep its properties intact: color, taste and aroma. Extra virgin olive oil fears three insidious enemies: smells, light and heat ; therefore it is a good idea to keep it in a cool and dry environment with not excessive temperature variations, protected from light direct and from the air.
It is a good rule to consume it within 18 months of bottling, since after this period the fragrance and the flavor fade and more and more defects appear evident to make it unusable. The best containers are those made of stainless steel. Also the dark glass containers are excellent. Conservation material not must be transparent to light.