a modulating machine is used to extract and recover the essential oil from citrus fruit such as lemons , oranges , mandarins , grapefruit , etc . not removing their peel , but by microperforating it and disrupting oil cells . the oil thus extracted is trapped in water so as to form an aqueous emulsion . the created machine includes a set of grooved disks mounted over corresponding supporting axes ; a base structure on which lower portion there is a transmission set installed , formed by pulleys and chains or grooved belts operated by a motor ; a set of supporting axes provided with alternate axial and rotational movement , by a set of operation members interconnected to rod transmitting alternate movement to the connected handles , alternating to the ends of the supporting axes . the machine also includes an emulsion tank laterally provided with collectors ; spillway ; disk cleaning set fruit washing and drying unit ; and an automatic lubrication system for application of oil and grease at specific points .