Studies on vacuum drying of coconut

Abstract

The coconut (cocos nucifera) has multifarious uses. The coconut oil is a good source of MCFA and has higher degree of digestibility. It is mostly included in diets all over the world. Traditional method of oil extraction has many limitations which results in low quality oil. An investigation was undertaken to study the effect of vacuum drying of coconut and also to study the quality of the dried kernel. Grated coconuts were dehydrated under three vacuum levels and two temperatures in a vacuum drier to optimize drying process. Vacuum levels used were 640, 600 and 510 mm of Hg vacuum (gauge). Sun dried samples were taken as control. Drying characteristics were studied by plotting drying curve. Oil was extracted by solvent extraction method and different quality tests were done. The oil extracted from samples dried at 640 mm Hg vacuum (gauge) and 50 ̊C resulted in an excellent quality product with faster drying rate and other quality attributes such as high oil content, low acid and iodine values and no rancidity. Therefore a vacuum level of 640 mm Hg (gauge) and a chamber temperature of 50°C may be chosen as optimum operating parameters for vacuum drying of coconut.