• Nonglyceride components are present in all fats but vary in content.
• These components can impact the characteristics of fats and oils.

1️⃣Phosphatides

• Phosphatides Composition:
  • Composed of a polyhydric alcohol, often glycerol.
  • Esterified with fatty acids.
  • Contains phosphoric acid.
  • Combined with a basic nitrogen-containing compound like choline, betaine, or ethanolamine.
• Common Phosphatides:
  • Lecithin and cephalin are two common phosphatides.
  • They are substituted triglycerides, where one fatty acid radical is replaced with phosphoric acid.
  • Fatty acid radicals can be both saturated and unsaturated.
• Esterification in Lecithins:
  • In lecithins, the phosphoric acid undergoes further esterification through the hydroxyl group of a choline molecule.

2️⃣Sterols

1. Definition of Sterol:
   • Sterol is an organic compound with the chemical formula C17H28O.
   • It is derived from gonane (C17H28) by replacing a hydrogen atom at position 3 with a hydroxyl group, making it an alcohol of gonane.
   • Sterols are a subgroup of steroids, which can contain the gonane structure, additional functional groups, and modified ring systems derived from gonane.
2. Natural Occurrence:
   • Sterols are naturally occurring compounds found in most eukaryotes, including plants, animals, and fungi.
   • Some bacteria can also produce sterols, albeit likely with different functions.
3. Animal Sterol:
   • The most well-known animal sterol is cholesterol, which plays a vital role in cell membrane structure.
   • Cholesterol also serves as a precursor to fat-soluble vitamins and steroid hormones.
4. Types of Sterols:
   • Sterols in plants are referred to as phytosterols.
   • Sterols in animals are known as zoosterols.
   • The primary zoosterol is cholesterol, while notable phytosterols include campesterol, sitosterol, and stigmasterol.
5. Ergosterol:
   • Ergosterol is a sterol found in the cell membrane of fungi, where it fulfills a role similar to that of cholesterol in animal cells.
6. Phytosterols (Plant Sterols):
   • Phytosterols, or plant sterols, have been studied in clinical trials.
   • They have been shown to block cholesterol absorption sites in the human intestine, contributing to the reduction of cholesterol absorption in humans.

3️⃣FATTY ALCOHOLS

1. Fatty Alcohols Overview:
   • Fatty alcohols are high-molecular-weight, straight-chain primary alcohols derived from natural fats and oils.
   • Their chain length can range from 4 to 26 carbons, varying depending on the source.
   • Examples include lauryl, stearyl, and oleyl alcohols.
2. Chemical Characteristics:
   • Fatty alcohols are usually colorless oils or waxy solids.
   • They typically have an even number of carbon atoms and a single alcohol group (–OH) at the terminal carbon.
   • Some are unsaturated, and others are branched.
3. Natural Occurrence:
   • Found in nature as waxes, which are esters of fatty acids and fatty alcohols.
   • Produced by bacteria, plants, and animals for various purposes, including buoyancy, metabolic water source, energy, biosonar lenses (marine mammals), and thermal insulation (in plants and insects).
4. Sources:
   • Historically, vegetable oils were a primary source of fatty alcohols.
   • Today, plant sources are preferred, producing a wider range of alcohols (C6–C24).
   • Coconut oil, palm kernel oil, and rapeseed/mustard seed oil are used to obtain different carbon chain lengths.