All oils have a specific function, independently of what they are made from, but not all are good alike. Some, such as olive oils, have more personality, and differ extensively one from another.
Extra virgin olive oils are an important component of sauces, because of their lubricating, non-stick properties, and their addition to the condiment confers a pleasant creaminess.
These functions however could also be carried out by other, more nondescript oils. What makes extra virgin unique is its intense aroma.
Since oil in sauces is a must, given its emulsifying and binding properties, it is essential to choose the right extra virgin, pairing it properly so that it won’t cover the flavour and perfume of the other ingredients.
White sauces. These delicate sauces call for an equally delicate, sweet oil, soft, buttery and harmonious. Should the oil have a stronger character, only scant amounts should be added.
Brown sauces. For these, it is best to use medium fruity, harmonious oils. Even if they possesses a powerful aroma and strong, pungent and bitter notes, they are fine, as long as they are perfectly balanced, so as not to alter the flavour of the sauce. Strongly fruity oils may be used too, but with due care and moderation.
How to use the more bitter, pungent oils. These are perfect with warm tomato sauces, such as classic, Provençale or Neapolitan sauces, or those where piquancy is an asset.
A last piece of advice. Never use too much oil, but always be moderate, so as not to alter the organoleptic balance of the dish (flavour, smell and tactile sensation).