1. LIPID Soluble in non-polar solvents and insoluble in polar solvents. Lipid is not polymers. Lipids: 1.Fatty acids 2.Neutral fats and oils 3.Waxes 4.Phospholipid 5.Sterols 6.Fat soluble vitamins

2. Fatty Acids

3. Saturated Fatty Acids Octanoic Acid

4. Unsaturated Fatty Acids 3 - Octenoic Acid 3, 6 - Octadienoic Acid Short hand:8:1 (  3) 8:2 (  3,6)

5. Cis 9 - Octadecenoic Acid (oleic) Trans 9 - Octadecenoic Acid (elaidic acid) Cis And Trans Fatty Acids

6. Polyunsaturated Fatty Acids Linoleic acid:Cis, cis, 9, 12 - Octadecadienoic acid Linolenic acid:Cis, cis, cis 9, 12, 15 - Octadecatrienoic acid Arachidonic acid:Cis, cis, cis, cis 5, 8, 11, 14 - Eicosatetraenoic acid Linoleic Acid Linolenic Acid Arachidonic Acid

7. Naturally-occurring fatty acids 1.Cis form 2.Not conjugated --- isolated double bond. 3.Even numbered fatty acids.

8. CLASSIFICATION OF FATTY ACIDS PRESENT AS GLYCERIDES IN FOOD FATS I. Saturated Fatty Acids ButyricButanoicCH3(CH2)2COOHbutterfat CaproicHexanoicCH3(CH2)4COOHbutterfat, coconut and palm nut oils CaprylicOctanoicCH3(CH2)6COOHcoconut and palm nut oils, butterfat CapricDecanoicCH3(CH2)8COOHcoconut and palm nut oils, butterfat LauricDodecanoicCH3(CH2)10COOHcoconut and palm nut oils, butterfat MyristicTetradecanoicCH3(CH2)12COOHcoconut and Palm nut oil, most animal and plant fats PalmiticHexadecanoicCH3(CH2)14COOHpractically all animal and plant fats StearicOctadecanoicCH3(CH2)16COOHanimal fats and minor component of plant fats ArachidicEicosanoicCH3(CH2)18COOHpeanut oil Common Name Systematic Name FormulaCommon source

9. Common Name Systematic Name FormulaCommon source II. Unsaturated Fatty Acids A. Monoethenoic Acids OleicCis 9-octadecenoicC17H33COOHplant and animal fats ElaidicTrans 9-OctadecenoicC17H33COOHanimal fats B. Diethenoic Acids Linoleic9,12-OctadecadienoicC17H31COOHpeanut, linseed, and cottonseed oils C. Triethenoid Acids Linolenic9,12,15-OctadecatrienoicC17H29COOHlinseed and other seed oils Eleostearic9,11,13-OctadecatrienoicC17H29COOHpeanut seed fats D. Tetraethenoid Acids Moroctic 4,8,12,15- Octadecatetraenoic C17H27COOHfish oils Arachidonic5,8,11,14- Eicosatetraenoic C19H31COOHtraces in animal fats

10. Common and Systematic Names of Fatty Acids Common Name Systematic Name FormulaCommon source A. Monoethenoic Acids OleicCis 9-octadecenoicC17H33COOHplant and animal fats ElaidicTrans 9-OctadecenoicC17H33COOHanimal fats B. Diethenoic Acids Linoleic9,12-OctadecadienoicC17H31COOHpeanut, linseed, and cottonseed oils C. Triethenoid Acids Linolenic9,12,15-OctadecatrienoicC17H29COOHlinseed and other seed oils Eleostearic9,11,13-OctadecatrienoicC17H29COOHpeanut seed fats D. Tetraethenoid Acids Moroctic 4,8,12,15- Octadecatetraenoic C17H27COOHfish oils Arachidonic5,8,11,14- Eicosatetraenoic C19H31COOHtraces in animal fats

11. Melting Points and Solubility in Water of Fatty Acids

12. C4- 8 - C6- 4970 C81675 C10316 C12440.55 C14540.18 C16630.08 Fatty AcidsM.P.(0C)mg/100 ml Soluble in H2O C18700.04 CHARACTERISTICS OF FATTY ACIDS

13. Effects of Double Bonds on the Melting Points 16:0 60 16:1 1 18:063 18:116 18:2-5 18:3-11 20:075 F. A.M. P. (0C) 20:4-50

14. FAT AND OILS Mostly Triglycerides: Glycerol 3 Fatty Acids

15. GLYCERIDES Monoglyceride (  - monostearin)Diglyceride (  ' - distearin) Triglyceride (  - palmityl distearin)

16.  - oleodipalmitin 1 - oleodipalmitin  - Linoleyldiolein 1 - Linoleyldiolein

17. FATS AND OILS ARE PRIMARILY TRIGLYCERIDES (97-99%) Vegetable oil - world supply - 68% Cocoa butter - solid fat Oil seeds - liquid oil Animal fat - 28% (from Hogs and Cattle) Marine oil - 4% Whale oil cod liver oil

18. Fatty Acids (%) of Fats and Oils 43 63 826 1036 12344 1410181 162611412 16:17 1 18:015632 18:12971824 18:2225354 Fatty AcidsButterCoconutCottonseedSoybean 18:32 8

19. MELTING POINTS OF TRIGLYCERIDES C6-15 C1215 C1433 C1645 C1855 C18:1 (cis)-32 TriglycerideMelting Point (°C) C18:1 (trans)15

20. WAXES Fatty acids + Long chain alcohol Important in fruits: 1.Natural protective layer in fruits, vegetables, etc. 2.Added in some cases for appearance and protection. Beeswax (myricyl palmitate), Spermaceti (cetyl palmitate)

21. PHOSPHOLIPID Lecithin (phosphatidyl choline)

22. STEROLS Male & female sex hormones Bile acids Vitamin D Adrenal corticosteroids Cholesterol

23. FAT SOLUBLE VITAMINS Vitamin A:

24. Vitamin D2: Vitamin E:

25. ANALYTICAL METHODS TO MEASURE THE CONSTANTS OF FATS AND OILS 1.Acid Value 2.Saponification Value 3.Iodine Value 4.Gas Chromatographic Analysis for Fatty Acids 5.Liquid Chromatography 6.Cholesterol Determination

26. 1. Acid Value Number of mgs of KOH required to neutralize the Free Fatty Acids in 1 g of fat.

27. 2. Saponification Value Saponification - hydrolysis of ester under alkaline condition.

28. Milk Fat210-233 Coconut Oil250-264 Cotton Seed Oil189-198 Soybean Oil189-195 Fat Saponification # Lard190-202 Saponification Value of Fats and Oils

29. Saponification # --mgs of KOH required to saponify 1 g of fat. 1.5 g in 250 ml Erlenmeyer. 2.50 ml KOH in Erlenmeyer. 3.Boil for saponification. 4.Titrate with HCl using phenolphthalein. 5.Conduct blank determination. B - ml of HCl required by Blank. S - ml of HCl required by Sample. 2. Saponification Value Determination

30. 3. Iodine Number Number of iodine (g) absorbed by 100 g of oil. Molecular weight and iodine number can calculate the number of double bonds. 1 g of fat adsorbed 1.5 g of iodine value  150.

31. Iodine Value = (ml of Na 2 S 2 O 3 volume for blank - ml of Na 2 S 2 O 3 volume for sample)  N of Na 2 S 2 O 3  0.127g/meq  100 Weight of Sample (g) Excess unreacted ICl Iodine Value Determination

32. Iodine Numbers of Triglycerides Palmitoleic Acid195 Oleic Acid186 Linoleic Acid2173 Linolenic Acid3261 Fatty Acids# of Double-bondsIodine # Arachidonic Acid4320

33. Compositions (%) of Fatty Acids of Fats 1552040 30 2 2035405 3 1050 40 4 2040 5 1020 1020 FatC4C6C10C16C18C18:1C18:2C18:3C20:4 6 100

34. 4. GC Analysis for Fatty Acids 1.Extract fat. 2.Saponify (hydrolysis under basic condition). 3.Prepare methyl ester (CH3ONa). 4.Chromatography methyl ester. 5.Determine peak areas of fatty acids. Fatty acids are identified by retention time. 6.Compare with response curve of standard.

35. Fatty Acids Methyl Esters: GC condition:10% DEGS Column (from supelco) Column temperature 200C.

36. 5.TRIGLYCERIDE ANALYSIS BY LIQUID CHROMATOGRAPHY Soybean Oil Solvent CH 3 CN/HF Column 84346 (Waters Associates)

37. Oleate-containing triglycerides in olive oil OL254:544 O2L54:446 OPL52:346 O354:348 OSL54:348 O2P52:248 O2S54:250 OPS52:150 Fatty Acid Composition Total Acyl Carbons: Unsaturation Equivalent Carbon Number OS254:152

38. 6. CHOLESTEROL DETERMINATION Enzymatic Determination: Cholesterol Oxidase 0-Dianisidine Oxidized 0-Dianisidine (Colorless)(Brown color)At 440 nm

39. Cholesterol by GLC 1.Prepare cholesterol butyrate. 2.Analyze by GLC. time in GC - 15 min. sensitivity - 10 -7 g.

40. Spectromertic Absorption Standard Curve of Cholesterol Cholesterol by GLC 1.Prepare cholesterol butyrate. 2.Analyze by GLC. time in GC - 15 min. sensitivity - 10 -7 g.

41. LIPID CONTENT ANALYSES 1.Gravimetric Method (1) Wet extraction - Roese Gottliegb & Mojonnier. (2) Dry extraction - Soxhlet Method. 2.Volumetric Methods (Babcock, Gerber Methods)

42. 1. Gravimetric Method (1)Wet Extraction - Roese Gottlieb & Mojonnier. For Milk: 1) 10 g milk + 1.25 ml NH4OH mix. solubilizes protein and neutralizes. 2) + 10 ml EtOH - shake. Begins extraction, prevents gelation of proteins. 3) + 25 ml Et2O - shake and mix. 4) + 25 ml petroleum ether, mix and shake.

43. (2) Dry Extraction - Soxhlet Method. Sample in thimble is continuously extracted with ether using Soxhlet condenser. After extraction, direct measurement of fat - evaporate ether and weigh the flask. Indirect measurement - dry thimble and weigh thimble and sample.

44. Soxhlet Method.

45. 2. Volumetric Method (Babcock, Gerber Methods) Theory: 1.Treat sample with H2SO4 or detergent. 2.Centrifuge to separate fat layer. 3.Measure the fat content using specially calibrated bottles. Methods: 1.Known weight sample. 2.H2SO4 - digest protein, liquefy fat. 3.Add H2O so that fat will be in graduated part of bottle. 4.centrifuge to separate fat from other materials completely.

46. REACTIONS OF FATS Hydrolytic Rancidity: 1. Triglyceride -> Fatty acids Specially C4 butyric acid (or other short chain fatty acids) are the real problem. 2. By lipase.

47. LIPID OXIDATION Major flavor problems in food during storage are mainly due to the oxidation of lipid. Lipid Oxidation - free radical reactions. 1.Initiation. 2.Propagation. 3.Termination.

48. Pentane Formation from Linolenic Acid

49. ANALYSIS OF FLAVOR QUALITY & STABILITY OF OIL 1.Peroxide Value Peroxide Value = ml of Na2S2O3  N  1000 (milliequivalent peroxide/kg of sample) Grams of Oil

50. 2. Active Oxygen Method (AOM) Determined the time required to obtain certain peroxide value under specific experimental conditions. The larger the AOM value, the better the flavor stability of the oil.

51. 3. TBA Test. To determine the rancidity degree of meat or fish product.