The Lipids

1. FON 241 Lipids; L. Zienkewicz The Lipids Chapter 5

2. FON 241 Lipids; L. Zienkewicz Fats in Food Provide essential fatty acids (EFA) Provide concentrated food energy Carry fat soluble vitamins Provide raw materials for synthesis Stimulate appetite, provide satiety

3. FON 241 Lipids; L. Zienkewicz The Lipids: There are three classes of lipids Triglyceride Phospholipid Sterol

4. FON 241 Lipids; L. Zienkewicz 1. Triglycerides 3 Fatty acids + 1 glycerol Combined together via a condensation reaction. Fatty acids do not typically occur in their free form in the body. Instead they are incorporated into triglycerides� 3 fatty acids and one glycerol bound together This is the chief form of fat in Fatty acids do not typically occur in their free form in the body. Instead they are incorporated into triglycerides� 3 fatty acids and one glycerol bound together This is the chief form of fat in

5. FON 241 Lipids; L. Zienkewicz

6. FON 241 Lipids; L. Zienkewicz Fatty Acids A component part of the triglyceride. A chain of Carbon atoms with Hydrogen attached: Has an Acid Group (COOH) at one end Has a Methyl Group (CH3) at the other end Found in most lipids in the body and in food. Lipids for a diverse groupd. But the have something in common: They all dissolve in organic solvents: cholroform, benzene, ether They are not soluble in water ie: separate from water. Fatty acids that are normally occurring will have an even number of carbons on their chains.Lipids for a diverse groupd. But the have something in common: They all dissolve in organic solvents: cholroform, benzene, ether They are not soluble in water ie: separate from water. Fatty acids that are normally occurring will have an even number of carbons on their chains.

7. FON 241 Lipids; L. Zienkewicz Saturated Fatty Acids Bonds between the Carbon atoms are single bonds. In other words: All of the Carbon atoms are �Saturated� with Hydrogen atoms. Sources: Animal fats. Usually solid at room temperature: butter, lard, etc. Nature requires that every carbon has 4 bonds� DRAW ON BOARD.Nature requires that every carbon has 4 bonds� DRAW ON BOARD.

8. FON 241 Lipids; L. Zienkewicz Unsaturated Fatty Acids Has at least one double bond between carbons. Are usually liquid at room temperature. Polyunsaturated: (many saturated) TWO or MORE carbon-carbon double bonds. Ex: Corn, soybean, safflower oils Monounsaturated: has ONE carbon-carbon double bond Ex: Canola oil, olive oil Not all fats from plant origin are unsaturated. Palm and coconut oils as well as cocoa butter are more saturated. They are thicker than other oils of plant origin because of their degree of saturation.Not all fats from plant origin are unsaturated. Palm and coconut oils as well as cocoa butter are more saturated. They are thicker than other oils of plant origin because of their degree of saturation.

9. FON 241 Lipids; L. Zienkewicz Essential Fatty Acids Must be supplied by the diet. Examples: (alpha-linolenic) Omega-3 fatty acid (linolenic) Omega-6 fatty acids Important for immune response, vision, cell structure, etc. We cannot synthesize all fatty acids in our bodies. Because of the position of the double bonds, our bodies cannot synthesize the Omega-3 and Omega -6 fatty acids, making them essential. These fatty acids play important roles in our bodies: immune system function, vision, form cell membranes, etc. We cannot synthesize all fatty acids in our bodies. Because of the position of the double bonds, our bodies cannot synthesize the Omega-3 and Omega -6 fatty acids, making them essential. These fatty acids play important roles in our bodies: immune system function, vision, form cell membranes, etc.

10. FON 241 Lipids; L. Zienkewicz Fatty Acids

11. FON 241 Lipids; L. Zienkewicz Saturation� Adds firmness- Saturated fats are more firm; solid at room temperature. Influences stability- polyunsaturated FA�s will go rancid (oxidation) more readily. Stability- Polu FA will go rancid first because their double bonds are unstable. Oxidation is the addition of oxygen to a compound, cause off-flavors and tastes.Stability- Polu FA will go rancid first because their double bonds are unstable. Oxidation is the addition of oxygen to a compound, cause off-flavors and tastes.

12. FON 241 Lipids; L. Zienkewicz Saturation: Hydrogenation Hydrogenation- Saturating a compound by adding Hydrogen atoms. Conversion of a polyunsaturated oil into solid margarine or shortening. Prolongs shelf-life, alters texture. Produces trans-fatty acids. Example: Margarine Hydrogen atoms are added to the carbon-carbon double bonds, making then single bonds- making them saturated. Hydrogen atoms are added to the carbon-carbon double bonds, making then single bonds- making them saturated.

13. FON 241 Lipids; L. Zienkewicz Saturation: Trans-fatty acids Trans-fatty acids- A result of hydrogenation. A change in shape from the �cis� form to the �trans� form. Behave more like saturated fats in the body A diet high in trans-fats has been linked to heart disease. Trans Fatty acids- the hydrogens next to the double bonds are on opposite sides of the chain. They have been asspciated with increased risk of CHD, increased LDL levels. Research has shown that trans-fats may even have a more serious adverse effect on CHD. Labeling of transfatty acids is Trans Fatty acids- the hydrogens next to the double bonds are on opposite sides of the chain. They have been asspciated with increased risk of CHD, increased LDL levels. Research has shown that trans-fats may even have a more serious adverse effect on CHD. Labeling of transfatty acids is

14. FON 241 Lipids; L. Zienkewicz