Investigation of Natural Pigments and Optical Properties for Some Sudanese Edible Oils Using UV - VIS Spectroscopy Techniques

Abstract

Edible oils are complex mixtures of organic substances of great commercial importance in the food, pharmaceutical, perfume and cosmetic industries due to their biological properties. This work was devoted to the detection of the total quantitative components of carotenoids and chlorophyll derivatives, as they are responsible for the color, which is an important qualitative characteristic of the oil because it contains antioxidants. Some optical properties of edible oils used in Sudan (corn, olive, peanut, factory sesame, presses sesame and sunflower) oil, purchased from local Sudanese stores were also measured and calculated using the method of UV-VIS spectroscopy (190-1100) nm. It was found that the absorption peak between (230-300) nm indicates the presence of di- and tri-unsaturated fatty acids. Polyphones share a band with different peaks between (300-400) nm. Carotenoids contribute a band with several peaks between (430 and 460) nm, and chlorophyll contribute another strong band at around (414, 670) nm. The results come to light similarity between the absorption spectrum, absorption coefficient and attenuation coefficient. From the transmission spectrum, it was found that corn oil and sunflower oil had the largest transmission spectrum and the lowest transmission spectrum of olive oil.