Lipids Fats, Oils, and Waxes
Types of Lipids 1. Triglycerides 95% of all eaten/stored 2. Phospholipids Soluble in oil and water 3. Sterols 4 fused ring structure
Triglycerides Glycerol + 3 Fatty Acids = Triglycerides (Dehydration Synthesis)
Triglycerides (continued) Fatty acid chains can be: Saturated – single bonds many hydrogens Unsaturated- double bond(s) fewer hydrogens -mono or polyunsaturated
Common Name Carbon Atoms Double Bonds Scientific NameSources Butyric acid40 butanoic acid butterfat Caproic Acid60 hexanoic acid butterfat Caprylic Acid80 octanoic acid coconut oil Capric Acid100 decanoic acid coconut oil Lauric Acid120 dodecanoic acid coconut oil Myristic Acid140 tetradecanoic acid palm kernel oil Palmitic Acid160 hexadecanoic acid palm oil Palmitoleic Acid161 9-hexadecenoic acid animal fats Stearic Acid180 octadecanoic acid animal fats Oleic Acid181 9-octadecenoic acid olive oil Ricinoleic acid hydroxy-9-octadecenoic acid castor oil Vaccenic Acid octadecenoic acid butterfat Linoleic Acid182 9,12-octadecadienoic acid grape seed oil Alpha-Linolenic Acid (ALA) 183 9,12,15-octadecatrienoic acid flaxseed (linseed) oil Gamma-Linolenic Acid (GLA) 183 6,9,12-octadecatrienoic acid borage oil Arachidic Acid200 eicosanoic acid peanut oil, fish oil Gadoleic Acid201 9-eicosenoic acid fish oil Arachidonic Acid (AA)204 5,8,11,14-eicosatetraenoic acid liver fats EPA205 5,8,11,14,17-eicosapentaenoic acid fish oil Behenic acid220 docosanoic acid rapeseed oil Erucic acid docosenoic acid rapeseed oil DHA226 4,7,10,13,16,19-docosahexaenoic acid fish oil Lignoceric acid240 tetracosanoic acid small amounts in most fats
Triglyceride- properties Non-polar = insoluble in water Solid (fat) or Liquid (oil) at room temperature High boiling points Energy
Energy from Triglycerides More chemical bonds to break Therefore Provide much energy Triglycerides [9kcal/g] > 2X Glucose [4kcal/g]
Uses of Edible Fats and Oils 1.Baking – moist tender and aerating 2.Emulsification- monoglycerides and phospholipids allow mixing of oil and water 3.Frying - high temperatures sear foods quickly and add flavor
Types Of Fatty Acid Chains 1.Saturated – single bonds, many H’s 2.Unsaturated a.Monounsaturated – 1 double bond b.Polyunsaturated – 2 or more double bonds
Phospholipids F.A. chains with Phosphate group attachment Partially soluble Ex.- lechithin in soy and egg yolk Cell membranes = phospholipid bilayer
Sterols Large, 4-ring structures Ex’s – a)Bile salts b)Hormones c)Cholesterol -used to stabilize cell membranes -also deposits on artery walls
Digestion of Lipids Chime moves from stomach to duodenum Emulsification – bile mixes with chime Enzyme - Lipase from pancreas