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Table 2 Lipid quality indices

From: Characteristics of lipids and their feeding value in swine diets

Item Description
Color Quantified relative to the Fat Analysis Committee (FAC) standard, ranging from 1 (light) to 45 (dark).
Fatty acid profile Relative amounts of individual fatty acids in a sample.
Free fatty acids Amount of fatty acids not bound to the glycerol backbone in a triglyceride.
Insolubles Amount of sediment in a sample. For example, fiber, hair, hide, bone, or soil.
Iodine value Measure of chemical unsaturation, expressed as grams of iodine absorbed by 100 g of fat. The iodine value can be calculated based upon fatty acid profile.
Moisture Amount of moisture in a sample.
Nonelutable material Reflects the total amount of non-nutritional material; includes moisture, impurities, unsaponifiable material, glycerol, and oxidized and polymerized fats.
Saponification value An estimate of the average molecular weight of the constituent fatty acids in a sample, defined as milligrams of KOH required to saponify 1 g of lipid. The greater the saponification value, the lower the average chain length.
Titer The solidification point of fatty acids in lipids, which is an important characteristic in producing soaps or fatty acids.
Total fatty acids The total of both free fatty acids and fatty acids combined with glycerol.
Unsaponifiables A measures of material in the lipid that will not saponify (form a soap) when mixed with caustic soda (NaOH or KOH). Examples include: sterols, hydrocarbons, pigments, fatty alcohols, and vitamins.