PROCESS DEVELOPMENT IN THE PRODUCTION OF VEGETABLE OIL FROM LOCAL RAW MATERIAL

Thesis Abstract

The project was melined on the process description of producing vegetable oil using locally made raw materials. To accomplish the aim of he project, the necessary steps which include extraction of the oil from the seed, pre-treatment like de-gumming, bleaching and deodorizing was also carried out. In the extraction stage, two different extraction process which include expeller pressing and solvent extraction was carried out on two different seeds which were palm kerned and soya bean. The result of the extraction showed that the palm kerned seed contains more oil than the soay bean seed. For expelle extraction, roller press was used and for solvent extraction two different solvents were used which include acetone and hexane. The characteristics of the two different solvent were compared as a result of this project. The de-gumming treatment on the oil was hinged oil was hinged at removing the gum which could be presents in the oil. In de-gumming operation the following chemical were used citric acid, sodium chloride and sodium silicate, other chemicals which could be used apart from those choosen for this project are sulphuric acid, hydochilonic acid, boric acid, salicyle acid, tartaric acid, inorganic phosphate and sequestering agents. For edible purpose, the most widely used e-gumming operation are hydration and hosphoric acid treatment and that was why they were used in this project. After the de-gumming operations, the alkali refining operation was carried out. the aim of this step ws to remove the free fatty acids which ave developed in the oil. The refining operation was also referred to as neutralization because of its objective. The operation involve the neutralization with caustic soda to form soap and free glycerol which was filtered off from the oil. The bleaching operation was carried out after the alkali refining to remove the colour pigment in the oil. The bleaching treatment available that could be use for oil bleaching are chemical treatment, heat treatment and bleaching by adsorption. The most important bleaching treatment used for edible oil is adsorption bleaching where filter earth like natural activated coal were used to adsorb the colour of the oil. The results of these operations carried out on palm kernel and soya bean showed that oil from palm kernel could be of high quantity but they were of low quality compare to soya bean oil which was of very low quantity when extracted but with high quality.