Abstract: . . .  terminate in an aldehyde group, are volatile and smelly. The fat is call rancid. Partial hydrogenation, of plant oils reduces rancidity because it reduces the number of homoconjugated polyunsaturated fatty acids. Isolated double bonds, as in oleic acid, do not oxidize under ordinary conditions. The joys of olive oil Page 6 6 We have seen that partial hydrogenation of polyunsaturated plant oils produces a spreadable fat, and reduces the tendency toward rancidity, but at the price of increased saturated and trans fatty acids, both of which, some people claim, are not sensible compounds to eat. Only recently are Americans becoming aware of what Italians and Greeks have known for thousands of years: olive oil is good for you. Unlike most plant oils such as soybean, corn, and safflower, which contain triglycerides made with polyunsaturated fatty acids, olive oil is almost pure glyceryl trioleate. . . .
. . .  Melting point Determine the melting point of the hydrogenated olive oil by placing it in a small disposable test tube in water at various temperatures. The approach is necessary because the melting point is low, and because it is impossible to get the material in a capillary tube. B. Spectroscopic analysis Infrared and elementary proton NMR will be used to explain the observed melting point. The details will be made more clear in a handout. For now, try to digest the rudiments of NMR.  . . .
. . .  arterioscleroic plaque, with subsequent infarctions and heart attack. Apparently, cis-trans isomerization, which is a side effect of catalytic hydrogenation, can kill you. In this experiment, we will hydrogenate olive oil, examine the properties of the product, and use infrared and nuclear magnetic resonance spectroscopy to explain the results. First, however, a brief discussion of fats and oils will be helpful. Fats and oils Catalytic Hydrogenation and Arteriosclerosis Page 2 2 Fats and oils are triglycerides, which consist of glycerol molecules esterified with three fatty acids. Fatty acids are essentially long hydrocarbon chains terminating in a carboxyl group. Stearic acid (18 carbons, saturated) is an example: Triglycerides are called fats if they are oils at (low melting point) and fats if they are solid (higher melting point). For instance, glyceryl tristearate, also called . . .
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