Percolation - Sinolea:

Rows of metal discs or plates are dipped into the paste. The oil preferentially wets and sticks to the metal and is removed with scrapers in a continuous process.

Advantages

- higher polyphenol content of oil

- low temperature method

- automated

- low labor

- oil/water separation step unnecessary

- low energy requirement

Disadvantages

- often must be combined with one of the above methods to

maximize oil extraction which requires more space, labor, etc.

- large surface areas can lead to rapid oxidation

Sale of future machines are currently outlawed in European Union due to difficulty in cleaning such large surface areas.