On food and cooking the science and lore of the kitchen ( PDFDrive ) 1505

unsaturated fat opens a space unprotected by hydrogen atoms on one side of the chain This exposes the carbon atoms to reactive molecules that can break the chain and produce small volatile fragments Atmospheric oxygen is just such a reactive molecule, and is one of the major causes of flavor deterioration in foods containing fats Water and metal atoms from other food ingredients also help fragmentfats and cause rancidity The more unsaturated the fat, the more prone it is to deterioration Beef has a longer shelf life than chicken, pork, or lamb because its fat is more saturated and so more stable Some small volatile fragments of unsaturated lipids actually have desirable and distinctive aromas The typical aroma of crushed green leaves and of cucumber both come from fragments of membrane phospholipids generated not just by oxygen, but by special plant enzymes And the characteristic aroma of deep-fried foods comes in part from particular fatty-acid fragments created at high temperatures Saturated and Unsaturated Fatty Acids in Foods and Cooking Fats Proportions of fatty acids are given as a percentage of the total fatty-acid content Fat Saturated Monounsaturated Polyunsaturat or Fatty Fatty Acids Fatty Acids Oil Acids Butter 62 29 Beef 50 42 Lamb 47 42 Pork 40 45 11 Chicken 30 45 21 Coconut oil 86 Palm kernel oil 81 11 Palm oil 49 37 ...characteristic aroma of deep-fried foods comes in part from particular fatty-acid fragments created at high temperatures Saturated and Unsaturated Fatty Acids in Foods and Cooking Fats Proportions of fatty... percentage of the total fatty-acid content Fat Saturated Monounsaturated Polyunsaturat or Fatty Fatty Acids Fatty Acids Oil Acids Butter 62 29 Beef 50 42 Lamb 47 42 Pork 40 45 11 Chicken 30 45 21 Coconut oil