**1.2 Utilisation of olive oil wastes**

Alperujo presents many environmental problems due to its high organic content and the presence of phytotoxic components that make its use in further bioprocesses difficult (Rodríguez et al., 2007a). Most of these components mainly phenolic compounds, confer bioactive properties, to olive oil. The extraction of the phenolic compounds has a double benefit: the detoxification of wastes and the potential utilisation as functional ingredients in foods or cosmetics, or for pharmacological applications (Rodríguez et al., 2007a). Although olive mill wastes represent a major disposal problem and potentially a severe pollution problem for the industry, they are also a promising source of substances of high value. In the olive fruits, there is a large amount of bioactive compounds, many of them known to have beneficial health properties. During olive oil processing, most of the bioactive compounds remain in the wastes or alperujo (Lesage- Meessen et al., 2001).Therefore, new strategies are needed for the utilisation of this by-product to make possible the bioprocess applications and the phase separation of alperujo.

Until now, efforts focussed on detoxifying these wastes prior to disposal, feeding, or fertilisation/composting, because they are not easy degradable by natural processes, or even used in combustion as biomass or fuel (Vlyssides et al.*,* 2004). However, the recovery of high value compounds or the utilisation of these wastes as raw matter for new products is a particularly attractive way to reuse them, provided that the recovery process is of economic and practical interest. This, added to the alternative proposals to diminish the environmental impact, will allow the placement of the olive market in a highly competitive position, and these wastes should be considered as by-products (Niaounakis & Halvadakis, 2004).
