The malaxation phase completes the development process of flavours and the organoleptic properties of olive oil started in the crushing phase. Malaxing involves slowly stirring the paste while it is thermal conditioning which causes the microscopic oil and water drops to coalesce, forming increasingly larger drops. The shape, volume and size of the paddles and the number of revolutions are key factors in obtaining the maximum yield and quality.
Pieralisi malaxing systems are composed of independent malaxer unit, suitable for both batch processing and industrial processing, designed to operate at different temperatures and speeds.
The optimum diameter of the Pieralisi malaxing tanks ensure top performance in heat exchange, reducing the possibility of the formation of emulsions. Larger volumes may reduce the efficiency of the heat exchange and require a longer malaxing time for the paste to achieve the optimal temperature. This can result in a loss in output of the process and a deterioration in the quality of the oil due to fermentation which may give it a winey taste and cause the very important values of alkyl esters to rise. The particular geometry of the paddles, the different diameter of the two blades and the angle of rotation make it possible to mix the paste thoroughly.
The rotation speed is set to prevent emulsion. The fully independent units are made of stainless steel, and have double walls for hot water circulation. Each unit is equipped with probes to check the minimum/ maximum level and temperature of the paste and also feature an automatically operated butterfly for draining them. Each unit has a washing system that operates on demand or at the end of processing each batch of olives. Pieralisi malaxing units are second to none. As a matter of fact, they are built according to the highest standards in terms of efficiency and effectiveness, ensuring the absolute lowest malaxing times and dramatically improve the quality of the oil. The Pieralisi Group produces tanks for 600 ÷ 2000 litres to meet all needs: from small batches to industrial-sized quantities. The top-of-the-line models allow the traceability of all parameters of the batch being processed.
• Maximum energy efficiency and reduced malaxing times thanks to the optimum diameter.
• No wastage since the paste is fed into the tank by means of a three-way valve.
• The modular design of the malaxer makes it possible to add even just one unit based on the miller’s requirements.
• Control of process parameters via an electronic control panel with a computerised touch screen.
• Processing can be done in each tank at different temperatures.
• Special automatic washing systems to ensure that each batch is not contaminated by the previous batch.
• The tanks are equipped with an electronic flow meter which measures the water added in three-phase processing and the draining process after each batch. A special device stops the pump if there is not enough water.