Serious tasting is held in an environment designed to eliminate as many outside influences as possible.
Professional tasting for the classification of olive oils is done in special tasting facilities where tasters have no contact with each other and the oils are heated to a standard temperature (around 26°) and tasted in blue glasses specially designed for tasting. The number of oils tasted is limited to 4 per day to eliminate the cumulative effects and fatigue caused by over stimulation of smell and taste receptors.
In a commercial tasting – such as an assessment of oils offered for sale – the tasting routine is more comparative and more oils will be tasted in a session.