Process design of virgin coconut oil (VCO) production using low-pressure oil extraction

Abstract

Virgin coconut oil (VCO) has become one of the most prominent high-value coconut product in coconut producing countries because of its versatility. This research attempts to design a fresh-dry process based on the Low-Pressure Oil Extraction Method for the production of VCO to reduce the settling time of the oil after extraction, that usually takes 1-2 weeks. Different parameters, such as drying temperature, centrifuge speed, and centrifugation time were varied and analysed. Three mathematical models were examined to describe the drying behaviour of the grated coconut meat at 65, 70, and 75°C using a tray dryer. A VCO production fresh-dry process based on the Low-Pressure Oil Extraction Method was developed through the employment of a centrifuge. The modified method lessens the settling time while still producing standard quality VCO. As predicted by the Laplace Transform Model, the shortest time for the comminuted coconut meat to reach a moisture content of 11% at which oil from nuts can be extracted using low pressure is at 29.07 minutes using a tray dryer. The best setting of VCO production using the modified method is at a drying temperature of 70°C and at 2700 RPM and 60 minutes of centrifugation as it produced the clearest oil with a yield of 92.84 % v/v and a recovery of 18.43%. The produced VCO was tested for free fatty acid (FFA), moisture and volatile matter, colour, peroxide value, and iodine value, and the results are 0.03%, 0.11%, 0R/0.3Y, 0, and 5.77, respectively, which all passed the Philippine National Standards for VCO.