FT-NIR spectroscopic analysis of fats and oils is fast, requires no sample preparation, and can analyze multiple parameters with a single measurement. An infrared spectrum of an oil contains a wealth of information that can be used to determine important factors. For example, the OH stretching region can indicate the presence of moisture or hydroperoxides, the latter commonly measured by the chemical PV test. The intensities of the bands in the CH region and of the ester linkage absorption are related to the average molecular weight of oil, commonly evaluated by SN determinations. The COOH absorption is indicative of lipolysis or free fatty acid (FFA) content of an oil. The presence of spectral features related to aldehydes and ketones, as well as conjugated dienes, suggests accumulation of secondary oxidation products commonly measured by the thiobarbituric acid (TBA) test or the AV test. The isolated trans band provides a direct measure of isolated trans isomers, and the combination of CH cis and CH trans absorptions provides a measure of total unsaturation or IV. The complete spectrum of a refined, melted fat characterizes its overall triglyceride composition, which in turn can be related to its SFC and also provides information about the relative amounts of saturated, monounsaturated, and polyunsaturated fatty acids in a fat or oil.