This operation consists in the continuous working and mixing of the crushed olive mass in the large basin described above until it reaches a uniform degree of density. The operation also reduces the oil and water emulsion and increases the yield of pure olive oil.

Percolation

This is an operation performed with machinery that was invented in relatively recent years. It originated from the observations of a Spanish technician concerning the adhesion of oil and water to the sides of metal strips. The latter were dipped into an emulsion of olive oil and water during a series of experiments. Analysis of the substance on the strip after withdrawal showed that more oil than water remained on it.
The water ran off freely; the oil was stripped off easily and rapidly with a simple tool resembling a caliper. At this point it was postulated that the residual water could be easily drawn off with well known existing techniques and equipment already in practice.
Automatic equipment (a percolator) for oil recovery was designed, built and put into operation. The oil and water were stripped from the metal strips into a container then drawn therefrom into a process of centrifugation that separates the two substances. The installation was successful after a very short run-in period. It is a process used today in the most modern olive oil production plants.

• Defoliating and washing the olives
• The olive crushing operation