Use of Raman Spectroscopy for Analysis and Detection of Some Sudanese Edible Oils

Abstract

Vegetable edible oils provide high nutritional and health value in the Sudanese diet. It is also used in the pharmaceutical industry and an essential ingredient in cosmetics. This paper reviews the use of Raman spectroscopy for the analysis, quality and characterization of edible oils, including six types of oils (corn, extra virgin olive, sunflower, factory sesame, presses sesame, and peanut) purchased from local Sudanese stores. The results showed that the spectra of edible oils are similar, but they show some differences that, despite their smallness, allow them to be distinguished from each other. Divide the spectrum into the fingerprint region. The range ranges between (600 and 1800) cm^-1 the silent region", this spectral region is (1800 to 2500) cm^-1, and range is from (2500 to 3400) cm^-1, known as the "high wave number region". Raman spectra also pliable the determination of the degree of saturation and unsaturation of oils. This characteristic is related to the value of iodine, and the degree of unsaturation can be used to classify and approve oils, which is especially useful with high-quality oils in the appearance of the vibration modes at 1155 cm^-1 and 1525 cm^-1. Adulteration of edible oils with cheaper oils is a major concern in the oil industry. The capabilities of a Raman spectrometer were checked to assess the purity of the samples (peanut spectrum and presses sesame spectrum). Raman spectroscopy allowed the examination of secondary components such as sterols, hydrocarbons, terpene alcohols and polyphenols. Raman spectroscopy is used because this innovative method provides fast, non-destructive and reagent-free measurements, samples do not need to be processed and do not require large volumes.