Effect of processing parameters on coconut oil expression efficiencies

Abstract

The effect of process parameters on oil expression efficiency from freshly dried coconut gratings was investigated. The range of parameters investigated were: pressing time, 4 and 8 min; particle size, fine (0.6 - 1.18 mm) and coarse (1.18 - 2.36 mm); pressure, 3-33 MPa; moisture content, 3%, 7%, 11% and 15%; and temperature, 30 degrees C, 60 degrees C and 90 degrees C. Results showed that 8 min of pressing and finer particles both led to significantly (P < 0.05) higher oil expression efficiency. The pressure increase within the range 3-13 MPa led to significantly higher oil yields, with yields leveling off thereafter. The effect of pressure increase was highly associated with the moisture content of the gratings, and the optimum moisture content under low-pressure pressing was found to be 11%. A pressing temperature of 60 degrees C led to higher oil expression efficiency, whereas a further increase of temperature to 90 degrees C did not lead to a significant increase in oil yield.

Optimisation of microwave‐assisted extraction of Gac oil at different hydraulic pressure, microwave and steaming conditions

“…A possible explanation is that the optimum microwave drying time resulted in rupturing the cell membrane (Oberndorfer et al ., ; Chan et al ., ) and hence assisted the enhanced release of carotenoids. Furthermore, the microwave‐dried Gac tissues can be softened and broken down under hot steaming process (Mpagalile & Clarke, ). As a result, the oil‐dissolving β‐carotene and lycopene were easily released by pressing.…”

“…To obtain a good quality of plant oil, in general, plant materials such as Gac fruit are extracted using a hydraulic press. The oil yield is often low (Bargale et al ., ; Owolarafe et al ., ); therefore, several treatments such as air drying and hot steaming before pressing were employed to enhance the extraction efficiency (EE) (Fasina & Ajibola, ; Mpagalile & Clarke, ). However, the oil quality may be degraded due to using heat in the processing steps.…”

Exergetic Efficiencies Evaluation of Flows and Operations on the Mechanical Extraction Process of &lt;i&gt;Jatropha curcas&lt;/i&gt; Oil

“…Oil recovery increases from a low moisture content of 1% (wb) to a maximum value at moisture contents between 4% and 5% (wb) for all applied pressures [37] [57]. Optimum moisture content for maximum oil yield during extraction process is 5% at low pressure [58]. During the drying process, 1 kg batches are oven dried at 30˚C, 65˚C, 80˚C.…”

Efecto de la Refinación Física Sobre el Aceite de la Almendra del Corozo (Acrocomia aculeata)

“…Igual tendencia se observó con la presión de prensado desde 2.000 psi hasta 8.000 psi, donde se estabilizó. En este sentido Mpagalile y Clarke (2005), reportaron en su investigación sobre la eficiencia del prensado de aceite de coco, un valor de presión (13 MPa) en la que no se producen igualmente cambios importantes en este parámetro. Por otra parte, es notorio destacar que entre 8.000 y 10.000 psi, no se presentaron diferencias apreciables en el rendimiento para un tiempo de prensado de 30 minutos, lo que se explica por el hecho de que transcurrido cierto tiempo y presión, el sedimento se hace incompresible, de modo que ya no es posible continuar la operación de prensado (Mafart y Béliard, 1994).…”