Specification and implementation of a continuous microwave-assisted system for paste malaxation in an olive oil extraction plant

• A microwave-assisted system (MWS) has been developed to condition the olive paste.
• Extraction efficiencies using the traditional system and MWS were compared.
• The use of the olive paste with microwaves promotes coalescence.
• The MWS allows the process of olive oil extraction to be continuous rather than batch.
• Extraction efficiencies using the traditional system and MWS are comparable.

An industrial prototype continuous microwave-assisted system (MWS) to condition olive paste was specified, built and implemented as an industrial process. The developed system was tested to assess its performance during implementation in an industrial olive oil extraction plant. The extraction efficiency of the olive oil plant was investigated for different operating conditions of the MWS and compared with conventional methods to condition the olive paste. The results indicate that exposing the olive paste to microwaves determines the thermal and non-thermal effects that influence the coalescence phenomena and the extraction efficiency.The experiments showed the feasibility of the continuous microwave-assisted prototype and great the potential to become an alternative technique to effectively condition olive paste. The MWS removes the limitations of the batch malaxation process and produces an olive oil extraction process that is truly continuous.