1 / 17

L IPIDS

Lipids are essential energy-rich water-insoluble compounds soluble in organic solvents like ether and chloroform. They are made of glycerol and fatty acids, with energy content higher than carbohydrates. Learn about lipid synthesis, properties, fats classification, and chemical reactions. Discover the significance of saturated and unsaturated fats, fatty acids isomers, and lipid content in feeds. Explore lipid analysis techniques, rancidity prevention, storage methods, and importance of antioxidants in lipid preservation.

sherice
Télécharger la présentation

L IPIDS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. LIPIDS

  2. LIPIDS • A water insoluble compounds, but soluble in ether, benzena, acetone andchloroform • Consists of glicerol & 3 fatty acids. Forms: solidlipid liquid fat • Energy contents 2.25 times higher than carbohydrate…….WHY??

  3. ENERGY OF LIPIDS • H:O higher than carbohydrate • They have higher Oxidation potential Ex. Butiryic acid C3H7COOH (4:1) Glucose C6H12O6 (2:1)

  4. Classifition: • Simple lipids: esther, fatty acids and glicerol • Mixed lipids: simplelipid + other molecules such as N, S, P etc • Lipids obtained from hydrolysis

  5. LIPID SYNTHESIS CH2OH HOOC-R CH2-OOC-R CHOH + HOOC-R  CH-OOC-R + 3H2O CH2OH HOOC-R CH2-OOC-R Glicerol fatty acid fat water

  6. Triacylglycerol Triglycerides R-COO-CH2 R-COO-CH R-COO-CH2 • Triglycerides found in seeds and • animal adipose. • Diglycerides found in plant leaves, • one fatty acid is replaced by sugar • (galactose).

  7. PROPERTIES Determined by structure of fatty acids: • Saturated (CnH2nO2) • Unsaturated (CnH2n-xO2)

  8. SATURATED FATS • Ex. Acetic acid CH3COOH Butyric acid C3H7COOH Caproic C5H11COOH Caprylic C7H15COOH Capric C9H19COOH Lauric C11H23COOH etc

  9. UNSATURATED • They have double bounds • Ex. Palmitoleic acid C15H29COOH Oleic acid C17H33COOH Linoleic acid C17H31COOH Linolenic acid C17H29COOH Arachidonic acid C19H31COOH

  10. Most Common Fatty Acids in Di- and Triglycerides CH3(CH2)nCOOH

  11. Fatty Acid Isomers

  12. Lipid Content of Feeds • Forages • Fat content is low: 1 to 4% of dry matter • High proportion of linolenic acid (18:3) • Diglycerides in fats of leaves • Grains • Fat content variable: 4 to 20% of dry matter • High proportion of linoleic acid (18:2) • Triglycerides in oils of seeds

  13. CHEMICAL REATIONOF FAT • HYDROLISIS • ENZYMATIK (in GIT) • WITH ALKALI (SAPONIFICATION) Lipid+alkalineglicerol salt alkaline fatty acid

  14. CHEMICAL REACTION (CONT...) 2. ANALYSIS • Saponification score- No.of mg KOH needed to form 1 gr fat • Fatty acids score- No.of mg KOH needed to neutrilisefree fatty acid from 1 gr of fat • Polenske score- No.of mg KOH neede to neutraliseinsoluble fatty acidsfrom 5 gr of fat

  15. CHEMICAL REACTION OF FAT d. Iodine score (unsaturation level) - gr iodine absorbed by 100 gr lipid (each double bounds of fat can take 2 iodine atoms) e. Ranacidity Test (level of rancidity) - Peroxida score (using KI) - Tiobarbiturate test - Oven Schaal test

  16. RANCIDITY • HYDROLITIC Presence of lipase causes this reactionto formfatty acid+glicerol NV of feed is not affected • OXIDATIVE Occured by the presence of oxigen Energi value of fat reduced

  17. PREVENTION • ANTIOXIDANT Compund preventing the occurence of lipid oxidation (rancidity) # PRIMER (to stop chained reaction offree radical formation to release H) # SEKUNDER (to prevent the action of prooxidant) • HYROGENISATION ---- lessreaktve 3. Good storage

More Related