Fatty acid profiles, correlation of iodine value, refractive index of heated, unheated palm kernel oil and palm olein.

Abstract

Consumption of palm kernel oil and palm olein in Nigeria is on the increase, this is because palm kernel oil is cheap and readily available. Heated palm kernel oil and palm olein were determined for iodine values, refractive indices and fatty acid profiles of heated palm kernel oil and palm olein, at temperatures of 100, 150, 200OC and time intervals of 20, 40 and 60mins were determined. The fatty acid profile of palm kernel oil shows that lauric acid and oleic acid were the dominant fatty acids with a total of about 60.13% to the fatty acid pool of the oil. The fatty acid profile for palm olein showed palmitic acid (C16.0) contributing a total of 36.60% and oleic acid (C18.1) contributing 46.18%, making both palmitic acid and oleic acid the major fatty acids with a total of 84.78% of the total fatty acid profile.  Palm kernel oil was apparently more stable during heating than palm olein with respect to iodine values.  Strong positive correlation was observed between iodine values and refractive index values which was statistically significant at P≤ 0.05  except for oils heated at 100 and 200OC for 40mins.The results indicate that  iodine number of heated,  unheated palm olein and palm kernel oil can be determined by calculation from the measurement of refractive index with an accuracy comparable to  chemical methods, provided that the instrument used in the determination of refractive index  is sufficiently accurate and  the measurements are carefully made.Keywords-: dominant, fatty acid profile, apparently, correlation, accuracy, chemical methods