Food Lipids : Food Lipids Professor David B. Min
Department of Food Science and Technology
The Ohio State University
Columbus, Ohio 43210
Min.2@osu.edu
http://class.fst.ohio-state.edu/fst821
DESCRIPTION : DESCRIPTION This course will cover an in-depth study of chemical and physical properties of edible fats and oils and the roles of their functional properties in food systems. Major topics covered will be chemistry of triglycerides, auto and thermal oxidation, antioxidants, chemical reactions in deep-fat frying, principles and application of polymorphism, interesterification and hydrogenation, fractionation of fats and oils, current instrumental analyses of lipids and biotechnology of fats and oils.
OBJECTIVES : OBJECTIVES To describe the relationship between the composition of tryglycerides and their chemical and physical properties.
To describe the chemical reactions of auto and thermal oxidation of oil and the mechanisms of antioxidants.
To describe the chemical mechanisms of hydrogenation and interesterification and their applications in fats and oils.
OBJECTIVES : OBJECTIVES To apply the physical and chemical methods to convert readily-available fats into tailor-made fats, that may be in greater demand or more desirable economically or nutritionally than the original fats.
To describe the current instrumental and analytical methods as research tools in the fats and oils area.
To describe the application of biotechnology to the modification and production of fats and oils.
GRADING : GRADING
Exams (3) 60%
Final Exam 30%
Homework Assignments 10%
Course Schedule : Course Schedule Class Topics
1. Introduction and Classification of Lipid
2. Chemistry of Fatty Acids
3. Chemistry of Triglycerides
4. Chromatographic Analyses of Lipids
5. UV & IR Spectrometric Analyses
6. NMR Spectrometric Analyses
7. NMR Spectrometric Analyses
8. NMR and Mass Spectrometric Analyses
9. Mass Spectrometry
10. Mass Spectrometry
Course Schedule : Course Schedule
Class Topics
11. Identification of Lipid Compounds by IR, NMR, MS
12. Examination
13. Lipid Oxidation - Chemistry of Oxygen
14. Free Radical Lipid Oxidation
15. Free Radical Lipid Oxidation
16. Singlet Oxygen Lipid Oxidation
17. Singlet Oxygen Lipid Oxidation
18. Singlet Oxygen Oxidation in Milk Products
19. Enzymatic Lipid Oxidation
20. Evaluation of Flavor Quality and Stability
Course Schedule : Course Schedule Class Topics
21. Chemical Reactions in Deep-Fat Frying Oils
22. Examination
23. Polymorphism
24. Application of Polymorphism in Foods
25. Interesterification
26. Interesterification
27. Hydrogenation
28. Hydrogenation
29. Examination
Reference Books : Reference Books 1. Flavor Chemistry of Fats and Oils by David B. Min and Thomas
H. Smouse. American Oil Chemists' Society, Champaign, IL. 1985
2. Flavor Chemistry of Lipid Foods by David B. Min and Thomas H.
Smouse. American Oil Chemists' Society, Champaign, IL. 1989
3. Food Lipids and Health by Richard E. McDonald and David B. Min.
Marcel Dekker, Inc. New York, NY. 1996
4. Food Lipids by Casimir C. Akoh and David B. Min, Marcel
Dekker, Inc. New York, NY.1998
5. Bailey's Industrial Oils and Fat Products by Y.H. Hui Wiley
Interscience. New York, NY. 1996
6. Food Chemistry, 3rd Edition by O. Fennema, Marcel Dekker, Inc.
New York, NY.1998
CLASSIFICATION OF LIPIDS : CLASSIFICATION OF LIPIDS
Triacylglycerol : Triacylglycerol
Simple Lipids : Simple Lipids A. Neutral fats - Triglycerides
Simple Lipids : Simple Lipids Waxes
Fatty acids + Long chain alcohol
Beeswax (myricyl palmitate)
Spermaceti (cetyl palmitate)
O C 30 H 61 O C C 15 H 31 O C 16 H 33 O C C 15 H 31
Simple Lipids : Simple Lipids Cholesterol and Esters 17 C H C H 2 C H 3 C H 2 C H 2 C H C H 3 C H 3 5 3 6 HO Fatty acids +
Simple Lipids : Simple Lipids Retinol (Vitamin A1) and Esters
Simple Lipids : Simple Lipids Vitamin D and Esters
R = C8H17 in Vitamin D3
R = C9H17 in Vitamin D2 6 5 7 R H O H 2 C 8 fatty acids +
CHEMISTRY OF FATTY ACIDS : CHEMISTRY OF FATTY ACIDS
Classification and Structure-Saturated Fatty Acids : Classification and Structure-Saturated Fatty Acids Common Name Systematic Name Formula
Butyric acid n-butanoic
Caproic acid n-hexanoic
Caprylic acid n-octanoic
Capric acid n-decanoic
Lauric acid n-dodecanoic
Slide19 : Common Name Systematic Name Formula
Myristic acid n-tetradecanoic
Palmitic acid n-hexadecanoic
Stearic acid n-octadecanoic
Arachidic acid n-eicosanoic
Behenic acid n-docosanoic
Lignoceric acid n-tetracosanoic
Monoethenoic Acid - Cis : Monoethenoic Acid - Cis 10 9 8 7 6 5 4 3 2 1 Δ 9, 10 - Octadecenoic acid
9 - Octadecenoic acid
Common Name of Fatty Acids : Common Name of Fatty Acids Common Name Systematic Name cis
Myristoleic 9-tetradecenoic acid
Palmitoleic 9-hexadecenoic acid
Oleic 9-octadecenoic acid
Vaccenic 11-octadecenoic acid
Erucic 13-docosenoic acid
Polyethenoic Acids : Polyethenoic Acids Common Name Systematic Name
Linoleic 9,12-octadecadienoic acid(cis,cis) or
Octadeca-9,12-dienoic acid
Linolenic 9,12,15-octadecatrienoic acid
Arachidonic 5,8,11,14-eicosatetraenoic acid
4,8,12,16-eicosatetraenoic acid
Ethynoic Acids : Ethynoic Acids Common Name Systematic Name
Tariric acid 6-octadecylinic acid
Hydroxy and Keto Acids : Hydroxy and Keto Acids Common Name Systematic Name
Dihydroxystrearic 9,10-dihydroxyoctadecanoic
Lactarinic 6-keto-octadecanoic
Cyclic Acids : Cyclic Acids Chaulmoogric acid
13-(2-cyclopentenyl) tridecanoic acid 4 5 1 3 2 C H 2 C H 2 C H ( C H 2 ) 12 C O H O C H C H
Triacylglycerol : Triacylglycerol
Fatty Acid Analysis : Fatty Acid Analysis 1. Method for oils :
a. measure 5 - 15 mg oil into small vial.
b. add 0.4 - 0.8 ml sodium methoxide.
c. heat 60C for 50 - 60 min.
d. add 0.4 - 0.8 ml saturated NaCl solution.
e. extract with 0.4 ml petroleum ether.
f. check derivertization (TLC-chloroform solvent).
g. Gas Chromatography analysis
Slide28 : 2. For quantification : the same as above except
a. add internal standard free fatty acid to oil.
b. add equal volumes of sodium methoxide and
BF3-methanol, 0.5 - 1.0 ml of each.
c. heat 70 - 80C for 50 - 60 min. (if, after 20 min.
of heating the sample is not dissolved, add more
sodium methoxide and BF3-methanol).
Fatty Acid Analysis
Slide29 : Disadvantages of Gas Chromatography Material has to be volatilized at 250°C without decomposition. R C OH CH 3 OH H 2 SO 4 O R C O CH 3 O CH 2 O C R CH O C R CH 2 O C R O O O CH 3 OH O R C O CH 3 CH 3 ONa Fatty Acids Methylester Reflux + 3 Volatile in Gas Chromatography Volatile in Gas Chromatography + +
Slide30 : Chromatogram of Fatty Acid Methyl Ester