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Chlorine Dioxide Gas Treatment of Cantaloupe and Residue Analysis Simran Kaur Purdue University

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Chlorine Dioxide Gas Treatment of Cantaloupe and Residue Analysis Simran Kaur Purdue University Purdue University Purdue e-Pubs Open Access Theses Theses and Dissertations 2013 Chlorine Dioxide Gas Treatment of Cantaloupe and Residue Analysis Simran Kaur Purdue University Follow this and additional works at: https://docs.lib.purdue.edu/open_access_theses Part of the Food Science Commons Recommended Citation Kaur, Simran, "Chlorine Dioxide Gas Treatment of Cantaloupe and Residue Analysis" (2013). Open Access Theses. 47. https://docs.lib.purdue.edu/open_access_theses/47 This document has been made available through Purdue e-Pubs, a service of the Purdue University Libraries. Please contact [email protected] for additional information. CHLORINE DIOXIDE GAS TREATMENT OF CANTALOUPE AND RESIDUE ANALYSIS A Thesis Submitted to the Faculty of Purdue University by Simran Kaur In Partial Fulfillment of the Requirements for the Degree of Master of Science December 2013 Purdue University West Lafayette, Indiana ii Two cantaloupes were in love. One said to the other, “Let’s run away together!” The other one said, “No. We cantelope.” iii ACKNOWLEDGEMENTS I would like to thank Dr. Mark Morgan for giving me the opportunity to work on this project. I truly appreciate his support, encouragement and guidance and have thoroughly enjoyed every moment. I would also like to thank my committee members, Dr. Mario Ferruzzi and Dr. Peter Hirst for their suggestions, feedback and comments. Thank you to Ben Paxson for his help with equipment and also to Dr. Applegate for the lab space to do my project. I am also thankful for the help and support from all my friends, old and new, close and far, for their support and companionship throughout my graduate studies, especially my dear friend Nadra Guizani. Most importantly, thank you to my parents and my brother. I find my strength in their constant support, belief and love. And of course, thank you music, caffeine and cantaloupes. iv TABLE OF CONTENTS Page LIST OF TABLES ............................................................................................................ vii LIST OF FIGURES .......................................................................................................... xii LIST OF ABBREVIATIONS .......................................................................................... xiv ABSTRACT ............................................................................................................. xv CHAPTER 1. INTRODUCTION ................................................................................. 1 CHAPTER 2. LITERATURE REVIEW ...................................................................... 9 2.1 Chlorine Dioxide Properties ................................................................................... 9 2.2 Generation of Chlorine Dioxide............................................................................ 12 2.3 Applications .......................................................................................................... 13 2.4 Regulations ........................................................................................................... 17 2.5 Analytical Methods ............................................................................................... 18 2.5.1 Standard Method 4500-ClO2 C, Amperometric Method I .......................... 19 2.5.2 Standard Method 4500-ClO2 D, DPD Method. ........................................... 20 th 2.5.3 Standard Methods (18 Edition)-4500-ClO2 E, Amperometric Method II . 20 2.5.4 USEPA Method 300.0 Ion Chromatography ............................................... 21 2.5.5 USEPA Method 300.1 Determination of Inorganic Anions in Drinking Water by Ion Chromatography .................................................................... 21 2.5.6 Other Analytical Methods ............................................................................ 22 2.6 Previous Work: Detection of Chloroxyanion Residues in Foods Treated with ClO2 ...................................................................................................................... 24 2.7 Project Analytical Method .................................................................................... 27 CHAPTER 3. PRELIMINARY EXPERIMENTS ..................................................... 29 3.1 Introduction ........................................................................................................... 29 3.2 Materials and Methods .......................................................................................... 30 3.2.1 Materials ...................................................................................................... 30 3.2.1.1 Radiolabeled Materials ...................................................................... 30 3.2.1.2 Non-radiolabeled materials: .............................................................. 30 3.2.1.3 Test commodity: ................................................................................ 31 3.2.2 Methods........................................................................................................ 31 3.2.2.1 Liquid Scintillation Counter (LSC) ................................................... 31 3.2.2.2 Ion Chromatography (IC) .................................................................. 32 3.2.2.3 [36Cl] Chlorine Dioxide Gas Treatment of Test Commodity ............ 33 v Page 3.3 Sample Calculation for Analysis of Data.............................................................. 43 3.3.1 Gas Samples ................................................................................................. 43 3.3.2 Trap and Rinse Solutions ............................................................................. 47 3.3.3 Slurry and Serum Samples ........................................................................... 51 3.3.4 Fractionation Of Residues Via Ion Chromatography .................................. 57 3.4 Results ................................................................................................................... 67 3.4.1 Gas Samples ................................................................................................. 67 3.4.2 Trap and Rinse Solutions ............................................................................. 70 3.4.3 Cantaloupe: .................................................................................................. 71 3.5 Discussion ............................................................................................................. 75 3.5.1 Gas Samples: ................................................................................................ 75 3.5.2 Trap and Rinse Solutions: ............................................................................ 76 3.5.3 Cantaloupe: .................................................................................................. 77 3.6 Conclusions ........................................................................................................... 78 CHAPTER 4. CHLOROXYANION RESIDUES IN CANTALOUPES TREATED WITH CHLORINE DIOXIDE GAS ................................................................................ 80 4.1 Introduction ........................................................................................................... 80 4.2 Materials and Methods .......................................................................................... 81 4.2.1 Materials ...................................................................................................... 81 4.2.1.1 Radiolabeled Materials ...................................................................... 81 4.2.1.2 Non-radiolabeled materials: .............................................................. 82 4.2.1.3 Test commodity: ................................................................................ 83 4.2.2 Methods........................................................................................................ 83 4.2.2.1 Liquid Scintillation Counter (LSC) ................................................... 83 4.2.2.2 Ion Chromatography .......................................................................... 83 4.2.2.3 [36Cl] Chlorine dioxide gas treatment of test commodity [36CDG] .. 84 4.3 Results ................................................................................................................... 97 4.3.1 Gas Samples ................................................................................................. 97 4.3.2 Trap and Rinse Solutions ........................................................................... 102 4.3.3 Cantaloupe ................................................................................................. 103 4.4 Discussion ........................................................................................................... 109 4.4.1 Gas Samples ............................................................................................... 109 4.4.2 Trap and Rinse Solutions ........................................................................... 110 4.4.3 Cantaloupe ................................................................................................. 111 4.5 Conclusion .......................................................................................................... 112 CHAPTER 5. CHLORINE DIOXIDE TREATMENTS, THEIR EFFECT ON RESIDUE CONCENTRATION AND ESTIMATION OF EXPOSURE TO RESIDUES ........................................................................................................... 114 5.1 Introduction ........................................................................................................
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