Twelve samples of butter were purchased from the local markets and compared with control butter sample made in the lab.. The samples were kept under cooling till analysis. The samples were analyzed by gas chromatography for the fatty acids content, and also chemically analyzed for cholesterol levels and fat content. The chromatographic analysis revealed that only three samples were identical to the control sample, while the other samples varied from the control regarding fatty acid composition. The results revealed that five samples showed a marked decrease in the total short chain acids when compared to the control sample. It could also observed that four samples had higher content of lauric acid (C12), while three samples possessed high content of palmetic acid (C16:0). On the other hand,, two samples were characterized with higher levels of oleic acid (C18:1 ), and stearic acid (C18:0 ). These findings show that an adulteration with palm kerenal oil, palim oil and tallow, was done, respectively. The results obtained from chromatographic analysis enabled to detect the adulteration by using the fatty acids ratios between certain fatty acids. The ratio between C12/C10, C14/C12, C18:1/C14, C18:0/C18:2, C18:1/C18 and the total saturated fatty acids/total unsaturated fatty acids, were used to detect the adulteration. The ratios between C12/C10, C18:0/C18:2, C18:1/C18:0, and total saturated fatty acids /total unsaturated fatty acids were useful in detecting the adulteration of butter fat with vegetable oils or tallow. Cholesterol content of the samples was carried out. The results obtained revealed that the addition of adulterants to the butter decreased the cholesterol level of the adulterated samples when compared to the control sample. The decrease of the cholesterol level seems to be proportional to the adulteration ratios. Also, calculating the cholesterol level of the suspected samples regarding the cholesterol level of the control samples helped to detect the ratios of adulterants in butter samples. Fat content of all samples did not differ.
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