|MadSci Network: Chemistry|
Like water, fat can exist in all three states of matter. The more saturated the fat, the higher the melting point. Also affecting whether a fat is a liquid or a solid is the “crystal” state of the fat when it solidifies. These have different melting points. Thus, under the conditions of butter manufacture, the fat will crystallize into a form that is solid at room temperature. Let’s also look at other fats and oils. Most “liquid oils” are refined. Part of the process is a “winterization” process. The oil is cooled down to refrigerator temperature and the “fat” that solidifies is removed. Vegetable shortening is simply vegetable oil that has been hydrogenated, i.e., the unsaturated fats are mostly turned into saturated fats and these fats are then solid, like butter.
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