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 100Â 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 1Â 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. |