Unsaponifiable matter

Substances present in fats and oils that are not glycerides and are resistant to saponification with strong alkalis. Unsaponifiable matter includes sterols, tocopherols, hydrocarbons (such as squalene), pigments, and fat-soluble vitamins — typically 1–2% of edible oils. Because its content and composition vary among different types of oils and fats, it serves as a valuable fingerprint for characterization and authentication, helping detect adulteration (e.g., olive oil diluted with seed oils). Determination involves saponifying the oil and extracting the unsaponifiable fraction with solvent; chromatographic profiling of sterols within it is a standard authenticity test.