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Photooxidation and Photosensitized Oxidation of Linoleic Acid, Milk, and Lard

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Photooxidation and Photosensitized Oxidation of Linoleic Acid, Milk, and Lard PHOTOOXIDATION AND PHOTOSENSITIZED OXIDATION OF LINOLEIC ACID, MILK, AND LARD DISSERTATION Presented in Partial Fulfillment of the Requirement for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By JaeHwan Lee, M.S. $ * * * $ The Ohio State University 2002 Dissertation Committee: Approved by Dr. David B. Min, Adviser Dr. Howard Q. Zhang Dr. Polly D. Courtney Adviser Dr. Hua Wang Food Science and Nutrition UMI Number: 3081938 UMI UMI Microform 3081938 Copyright 2003 by ProQuest information and Learning Company. Aii rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. ProQuest information and Learning Company 300 North Zeeb Road PO Box 1346 Ann Arbor, Mi 48106-1346 ABSTRACT Photooxidation and photosensitized oxidation on the formation of volatile compounds in linoleic acid, milk, and lard were studied by a combination of solid-phase microextraction (SPME)-gas chromatography (GC)-mass spectrometry (MS) and headspace oxygen content. Photooxidation is the oxidation under light in the absence of photosensitizers such as chlorophyll and riboflavin. Photosensitized oxidation is the oxidation under light in the presence of photosensitizers. Total volatile compounds in linoleic acid without added chlorophyll under light and in the dark did not increase for 48 hr at 4 °C. Total volatile compounds in linoleic acid with added 5 ppm chlorophyll under light at 4 °C for 0, 6, 12, 24, and 48 hr, increased from 8.9 to 11.6, 21.7, 26.1, 29.3 (IxlO"^) in electronic counts, respectively. 2-Pentylfuran, an undesirable reversion flavor compound in soybean oil, 2- oetene-l-ol, 2-heptenal, and l-oetene-3-ol were formed by photosensitized oxidation only. Light excited photosensitizers like chlorophyll can generate singlet oxygen from ordinary triplet oxygen. 2-Pentylfuran, 2-heptenal, and l-octene-3-ol can come from CIO, C l2, and CIO hydroperoxide of linoleic acid, respectively, which can be formed by singlet oxygen oxidation but not by triplet oxygen oxidation on linoleic acid. The singlet ii oxygen oxidation mechanisms for 2-pentylfuran, 2-heptenal, l-octene-3-ol, and 2-octene- l-ol from linoleic acid were proposed. Milk with or without added riboflavin, ascorbic acid, sodium azide, and hutylated hydroxyanisol (BHA) was stored at 4 °C under light and in the dark. Pentanal, dimethyl disulfides, hexanal, and heptanal were formed only in the light stored milk and increased significantly as the added riboflavin concentration increased from 5 to 10, 50 ppm (P<0.05). As fat content in milk increased from 0.5 to 1.0, 2.0, and 3.4%, pentanal, hexanal, and heptanal increased significantly (P<0.05) but dimethyl disulfide concentration did not change. BHA and ascorbic acid, hydrogen donating free radical scavengers, reduced hexanal and heptanal formation. Sodium azide, a singlet oxygen quencher, prevented dimethyl disulfide formation. Formation of pentanal is different from that of hexanal and heptanal in milk. Singlet oxygen and free radicals play important roles in the formation of volatile compounds in photosensitized milk. Volatile compounds and headspace oxygen content from lard containing 0 and 5 ppm chlorophyll in air-tight 10-mL bottles were studied at 55 °C under light and in the dark. Total volatile compounds in lard with 5 ppm chlorophyll under light were 19 times more than that in samples with 0 ppm chlorophyll for 48 hr. Headspace oxygen content in lard with 5 ppm chlorophyll under light changed from 21 to 15% for 48 hr but that in lard with 0 ppm chlorophyll did not change significantly (P>0.05). Photosensitizer-free lipid model system using lard was developed. Photooxidation mechanism seems to be a free radical chain reaction like autoxidation. Photosensitizers like chlorophyll and riboflavin play important roles in the formation of volatile compounds. Singlet oxygen, which can he generated from triplet iii oxygen by light excited photosensitizers, is involved in the formation of volatile compounds in linoleic acid, milk, and lard. Photosensitizer content in food should be minimized and food products should be packed with light impermeable package to prevent the photosensitized oxidation on lipids. IV Dedicated to my mother, my wife, my daughter, and my late father. V ACKNOWLEDGMENT I wish to thank my adviser, Dr. David B. Min for his energetic guidance and enthusiasm which made this dissertation possible. He gave me a chance to study in this charming field and showed me a way to taste the world of knowledge on lipid and flavor. It is my greatest pleasure to he his advisee in my academic study. I also thank my committee members, Dr s. Ahmed E. Yousef, Howard Q. Zhang, Polly D. Courtney, and Hua Wang for their valuable suggestions, consistent advisory and concerns throughout my graduate program. I also thank my colleagues and graduate school friends, Jeff Boff, Raymond Diono, Hyun-Jung Chung, and Dr. TaeHyun Ji for their memorable friendship and assistance. Most importantly, I would like to express my greatest appreciation to my mother, my wife, my daughter, and my late father. VI VITA January 26, 1970 ----------------------- Bom in Seoul, Republic of Korea 1988-1994 -------------------------------- B.S. Food Science and Technology Seoul National University, Seoul, Korea 1994-1996-------------------------------- M.S. Food Science and Technology Seoul National University, Seoul, Korea 1996-1999--------------------------------CheilJedang Food Company, Korea 1999-2002-------------------------------- Graduate Research Associate The Ohio State University, Columbus, Ohio, U.S.A. PUBLICATIONS 1. Steenson DF, Lee JH, and Min DB. Solid Phase Microextracion Analyses of Volatile Compounds of Soybean and Com Oils, J. Food Sci. 2002, 67(1), 71-76. 2. Chung MS, Lee JH and Min DB. Effects of Pseudomonas putrifaciens and Acinetobacter spp. on the Flavor Quality of Raw Ground Beef, J. Food Sci. 2002, 67(1), 77-83. 3. Yang WT, Lee JH and Min DB. Quenching Mechanisms and Kinetics of a- Tocopherol and (3-Carotene on the Photosensitizing Effect of Synthetic Food Colorant FD & C Red No.3, J. Food Sci. 2002, 67 (2), 507-510. V ll 4. Foley DM, Pickett K, Varon J, Lee JH, Min DB, Caporaso F and Prakash A. Pasteurization of Fresh Orange Juice using Gainnia Irradiation: Microbiological, Flavor and Sensory Analyses. J. Food Sci. 2002, 67(4),1495-1501. 5. Lee JH, Kang JH, and Min DB. Optimization of Solid Phase Microextraction on the Headspace Volatile Compounds in Kimchi, a Traditional Korean Fermented Vegetable Product. J. Food Sci.2002-0478 (In press). 6. Kang JH, Lee JH, Min S, and Min DB. Study of enzymatic and chemical changes of Kimchi, a Traditional Korean Fermented Vegetable Product. J. Food Sci. 2002- 0488 (In press). 7. Lee JY, Lee JH, Choi YO, and Min DB. Singlet oxygen oxidation and its effects on the soy flour off-flavor. J. AOCS (In press). 8. Lee JH, Ozcelik B, and DB Min. Electron donation mechanisms of (3-carotene as a free radical scavenger. J. Food Sci.2002-500 (In press). 9. Ozcelik B, Lee JH, and DB Min. Effects of Light, Oxygen and pH on the 2,2- Diphenyl-1 -Picrylhydrazyl (DPPH) method to evaluate antioxidants. J. Food Sci. (In press). 10. Lee JH, Diono R, Kim GY, and DB Min. Optimization of Solid Phase Microextraction on the Headspace Volatile Compounds in Parmesan Cheese. J. Agric. Food Chem. Jf025910+ (In press). 11. Kim GY, Lee JH, and DB Min. Study of Eight-Induced Volatile Compounds in Goat Cheese. J. Agric. Food Chem jf0259009a (In press). vm PUBLISHED ABSTRACT JH Lee and DB Min. Nuclear magnetic resonance (NMR) study on the electron donating ability of (3-carotene by using 2,2-diphenyl-1-picrylhydrazyl (DPPH). Institute of Food Technologist, Anaheim Ca. 2002 JH Kang, JH Lee, YT Ko and DB Min. Changes of headspace volatile compounds, oxygen, carbon dioxide and microorganisms in Kimchi stored at 5°c for 25 days. Institute of Food Technologist, Anaheim Ca. 2002 JH Lee, JH Kang, YT Ko and DB Min. Optimization of solid phase microextraction (SPME) on the headspace volatile compounds in Kimchi. Institute of Food Technologist, Anaheim Ca. 2002 JY Lee, JH Lee, EG Choe and DB Min. Analysis of volatile compounds and headspace oxygen and carbon dioxide in full fat soy flour. Institute of Food Technologist, Anaheim Ca. 2002 Ozcelik B, Lee JH and Min DB. The effects of chlorophyll, light and oxygen on the stability of 2,2-diphenyl-1-picrylhydrazyl radical in acetone and soybean oil. Institute of Food Technologist, New Orleans LA. 2001 Lee JH, Ozcelik B and Min DB. Evaluation of electron donating ability of (3-carotene by using soybean oil and 2,2-diphenyl-1-picrylhydrazyl (DPPH) in acetone system. Institute of Food Technologist, New Orleans LA. 2001 Diono R, Lee JH and Min DB. Solid phase microextraction-gas chromatographic analysis of cheese flavor compounds. Institute of Food Technologist, New Orleans LA. 2001 IX Chung MS, Lee JH and Min DB. Effects of Pseudomonas putrifaciens and Acinetobacter spp. on the Flavor Quality of Raw Ground Beef. Institute of Food Technologist, Dallas, TX. 2000 FIELD OF STUDY Major Field : Food Science and Nutrition X TABLE OF CONTENTS Page A bstract ......................................................................................................................... ii Dedication .................................................................................................................... v Acknowledgement ......................................................................................................
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