Yogesh Singh

  LIPIDS q   Fats and Oils belong to a group of compounds called lipids q   Contains larger proportions of carbon and hydrogen and smaller proportions of oxygen than carbohydrates q   More concentrated source of energy providing 2.25 times more energy than carbohydrates and proteins q   Lipids of importance for us are – fatty acids, fats, oils, sterols, phospholipids and lipoproteins Classification of Lipids •        Classified on the basis of structure q   Simple lipids- They constitute more than 98% of food and body fats. It is made up of 3 fatty acids attached to glycerol. They are triglycerides meaning more than 1 type of fatty acid is present in fat, e.g. Cooking oils and butter. q   Compound lipids- These are fats in which at least one fatty acid is replaced by carbohydrate, protein or phosphorus, i.e. They are fats + non-fat molecule, e.g. Phospholipids, glycolipids and lipoprotein. q   Derived lipids- They are breakdown products of fats and include diglyceride

  PROTEINS •        Proteins are large, complex, organic compounds made up of carbon, hydrogen, oxygen, and nitrogen •        Basic material of every living cell •        Only nutrient that can make new cells and rebuild tissues •        Amino acids are the basic units of it Each amino acid contains a carboxyl group (COOH) or acid group and an amino group (NH 2 ) or basic group •        Proteins consist of chains of amino acids that are linked to each other by a peptide linkage (-CO-NH-) •        Protein (containing 16% nitrogen) content measured by nitrogen content. Hence,1 gm nitrogen = 6.25 g protein Essential Amino Acids •        Cannot be synthesized in sufficient amounts by body •        Must be provided by diet, hence very essential for human beings. •        Human adult requires 8 whereas growing children require 10 essential amino acids. •        Examples: Isoleucine, leucine, lysine, methionine, tryptpphan, valine, histidine, arginine, etc. Non-essenti