It is important to select a fat with a high smoke point, at least above 420^oF (216^oC). This temperature is above the average range of temperatures used for deep-fat frying. Selecting a fat with a smoke point at or below the frying temperature will cause it to over-heat and decompose into glycerol and its individual fatty acids. The glycerol is further broken down (hydrolyzed) to a steel-blue smoke called acrolein. Acrolein’s sharp, offensive odor warns people of its presence. This smoke is extremely irritating and even harmful to the mucus membranes of the mouth and nasal passages. Read more »