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.
Objectives of the Study
The major objective of the study is the
comparative assessment of some physiochemical properties of groundnut
oil and palmolein sold in Nigeria.
1.4 Research Questions
(1) what is palmolein?
(2) How is it produced?
(3) what are its economic importance?
(4) why the need to conduct comparative assessment of some physiochemical properties of groundnut oil and palmolein?
1.5 Significance of the Study
This study gives a clear insight into
the comparative assessment of some physiochemical properties of
groundnut oil and palmolein sold in Nigeria. The findings of these
research will show if the physiochemical properties of palmolein
co.pares favourably with groundnut oil as it is used as a substitute for
1.6 Scope of the Study
This research focuses in the comparative assessment of some physiochemical properties of groundnut oil and palmolein.
There was difficulty experienced in the
procurement of pure groundnut oil needed for the research because most
of the groundnut oil are adulterated.
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