COMPARATIVE ASSESSMENT OF SOME PHYSIOCHEMICAL PROPERTIES OF GROUNDNUT OIL AND PALMOLEIN SOLD IN NIGERIA.
1.1 Background to the Study
Vegetable oils have wide application in foods where they are used in frying, cooking, salad dressing, shortening of pastry e.t.c ( N Baker et al., 1997). They mainly consists of lipids with some other minor components including antioxidants, colorants, flavours and emulsifiers (O. Fashina et al., 2006). Some of these compounds occur naturally and some are added during manufacturing process. The presence of hydrocarbons or mineral oils such as n-alkenes in vegetable oils has also been reported ( S. Johnson et al.,2009). Vegetable oils act as carriers if fat soluble vitamins (A,D,Eand K) and play important sensory and functional roles in food products. They provide the most concentrated source of energy, supply essential fatty acids, linoleic and linolenic acids which are precursors for important hormones, the prostaglandins and responsible for growth, provide safety and increases the palatability of food (V. Atasie et al., 2009).
In Nigeria, theajor sources of edible oils are groundnut and palmoil. These vegetable oils are used mainly as cooking oil and for the production of soap, margarine and cosmetics (C. Jambunathan and S. Reddy, 1991). The quality of vegetable bottling and storage (F. Shahidi, 2005). Therefore, appropriate control throughout the production chain is important to ensure physical and/or chemical parameters are usually monitored such as acidity, density, viscosity, color, refractive index, moisture, volatility, Di electric constant, total polar compounds, as well as saponification, peroxide, iodine, ester and carbonyl values. Oil quantity and it’s stability are therefore very important for the consumers and in application to industries (F. Wali et al., 2015). Various brands of vegetable oils are sold in markets, some are produced in the country while some are imported. Despite the strict regulations and enforcement by relevant regulatory agencies of the sale standard commodities to consumers, at times manufacturers and importers do not comply with standards. In spite of the wide range of applications of vegetable oils.
1.2 Problem Statement
Various research has been conducted on vegetable oils such as palm oil, groundnut oil, soya oil but not palmolein. Over the years due to the scarcity and high cost of groundnut oil, palmolein which is a fraction of palmoil has been use as a substitute for groundnut oil in household cooking. Hence there is need for comparative assessment of some physiochemical properties of groundnut oil and palmolein sold in Nigeria.
