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Effects of thermal processing conditions on mushroom antioxidants.

Ma Yam Tak. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 280-299). / Abstracts in English and Chinese. / Thesis Committee: --- p.i / Acknowledgements --- p.ii / Abstract --- p.iii / 摘要 --- p.vi / Content --- p.viii / List of Tables --- p.xvii / List of Figures --- p.xxiv / Abbreviations --- p.xxvi / Chapter Chapter 1: --- Introduction --- p.1 / Chapter 1.1 --- Reactive oxygen species (ROS) --- p.1 / Chapter 1.1.1 --- Definition --- p.1 / Chapter 1.1.2 --- Formation of ROS --- p.2 / Chapter 1.1.2.1 --- Homolysis --- p.2 / Chapter 1.1.2.2 --- Reaction with pre-formed odd-electron species --- p.2 / Chapter 1.1.2.3 --- Electron transfer --- p.3 / Chapter 1.1.2.4 --- Metabolism and cellular functions --- p.3 / Chapter 1.1.3 --- Sources of ROS in human --- p.4 / Chapter 1.1.4 --- Chemistry and Biochemistry of ROS --- p.6 / Chapter 1.1.4.1 --- Superoxide anion radical (O2、) --- p.6 / Chapter 1.1.4.2 --- Hydrogen peroxide (H2O2) --- p.8 / Chapter 1.1.4.3 --- Hydroxyl radical (HO) --- p.9 / Chapter 1.1.5 --- Lipid peroxidation --- p.10 / Chapter 1.2 --- Antioxidants --- p.11 / Chapter 1.2.1 --- Definition --- p.11 / Chapter 1.2.2 --- Mechanism of action --- p.11 / Chapter 1.2.3 --- Natural antioxidants --- p.13 / Chapter 1.2.3.1 --- Endogenous antioxidants --- p.13 / Chapter 1.2.3.2 --- Exogenous antioxidants --- p.14 / Chapter 1.2.4 --- Synthetic antioxidants --- p.15 / Chapter 1.3 --- Oxidative stress --- p.16 / Chapter 1.3.1 --- Balance between ROS and antioxidants --- p.16 / Chapter 1.3.2 --- Diseases associated with oxidative stress --- p.16 / Chapter 1.3.3 --- Beneficial effects of dietary antioxidants towards degenerative diseases --- p.18 / Chapter 1.4 --- Principles of assay --- p.21 / Chapter 1.4.1 --- Evaluation of antioxidant activity --- p.21 / Chapter 1.4.1.1 --- ABTS radical cation scavenging activity --- p.21 / Chapter 1.4.1.2 --- DPPH radical scavenging capacity --- p.21 / Chapter 1.4.1.3 --- p-carotene bleaching assay --- p.22 / Chapter 1.4.1.4 --- Ferric reducing antioxidant power --- p.23 / Chapter 1.4.1.5 --- Hydroxyl radical scavenging activity --- p.23 / Chapter 1.4.2 --- Determination of phenolic content --- p.24 / Chapter 1.4.2.1 --- Folin-Ciocalteu method --- p.24 / Chapter 1.4.2.2 --- Enzymatic method --- p.25 / Chapter 1.4.3 --- Determination of Hydroxymethylfurfural (HMF) --- p.25 / Chapter 1.5 --- Effect of food processing on antioxidant activity --- p.27 / Chapter 1.5.1 --- Blanching --- p.27 / Chapter 1.5.2 --- Drying --- p.29 / Chapter 1.5.2.1 --- Sun-drying or air-drying --- p.29 / Chapter 1.5.2.2 --- Oven-drying --- p.30 / Chapter 1.5.2.3 --- Infrared-drying or microwave-drying --- p.33 / Chapter 1.5.2.4 --- Freeze-drying --- p.34 / Chapter 1.5.3 --- Canning --- p.34 / Chapter 1.5.4 --- General thermal treatment --- p.36 / Chapter 1.5.5 --- Freezing --- p.37 / Chapter 1.6 --- Mushroom antioxidants --- p.44 / Chapter 1.6.1 --- Nutritional information --- p.44 / Chapter 1.6.2 --- Antioxidant activity of edible mushrooms --- p.44 / Chapter 1.6.3 --- Antioxidant components --- p.47 / Chapter 1.7 --- Objectives --- p.50 / Chapter Chapter 2: --- Method development --- p.63 / Chapter 2.1 --- Introduction --- p.63 / Chapter 2.2 --- Materials and method --- p.67 / Chapter 2.2.1 --- Standard preparation --- p.67 / Chapter 2.2.2 --- Preparation of mushroom crude extracts --- p.67 / Chapter 2.2.3 --- Optimization of the assay on mushroom extracts and standards / Chapter 2.2.3.1 --- Volume ratio between various reagents and samples --- p.69 / Chapter 2.2.3.2 --- Reaction kinetics --- p.69 / Chapter 2.2.3.3 --- Comparison of response of phenolic standards to the enzymatic method and the Folin Ciocalteu (FC) method --- p.70 / Chapter 2.2.3.3.1 --- Enzymatic method --- p.70 / Chapter 2.2.3.3.2 --- FC method --- p.70 / Chapter 2.2.4 --- Statistical analysis --- p.71 / Chapter 2.3 --- Results and discussions --- p.75 / Chapter 2.3.1 --- Sample-to-reagent volume ratio --- p.75 / Chapter 2.3.2 --- Reaction kinetics --- p.77 / Chapter 2.3.3 --- Response of phenolic standards to the enzymatic method and FC method --- p.82 / Chapter 2.3.3.1 --- General trends --- p.82 / Chapter 2.3.3.2 --- Mechanism in the response of phenolic standards to the enzymatic reaction --- p.84 / Chapter 2.3.3.3 --- Mechanism in the response of phenolic standards towards the FC method --- p.86 / Chapter 2.3.4 --- Response of interfering compounds to the enzymatic method and the FC method --- p.88 / Chapter 2.3.5 --- Response of mushroom crude extracts to the enzymatic method and the FC method --- p.89 / Chapter 2.4 --- Conclusion --- p.90 / Chapter Chapter 3: --- Mushroom screening --- p.92 / Chapter 3.1 --- Introduction --- p.92 / Chapter 3.1.1 --- Agrocybe aegerita (Aa) --- p.92 / Chapter 3.1.2 --- Volvariella volvacea (Vv) --- p.93 / Chapter 3.1.3 --- Lentinus edodes (Le) --- p.94 / Chapter 3.1.4 --- Agaricus bisporus (Ab) --- p.95 / Chapter 3.1.5 --- Processing need of fresh mushrooms --- p.95 / Chapter 3.1.6 --- Comparison of antioxidant activity of mushrooms --- p.96 / Chapter 3.2 --- Materials and methods --- p.98 / Chapter 3.2.1 --- Sample preparation --- p.98 / Chapter 3.2.2 --- Proximate analysis of the four fresh edible mushrooms --- p.99 / Chapter 3.2.2.1 --- Crude lipid --- p.99 / Chapter 3.2.2.2 --- Crude protein --- p.99 / Chapter 3.2.2.3 --- Ash content --- p.101 / Chapter 3.2.2.4 --- Total dietary fiber (TDF) content --- p.101 / Chapter 3.2.2.5 --- Moisture content --- p.103 / Chapter 3.2.3 --- Sample extraction --- p.103 / Chapter 3.2.4 --- Total phenolic content --- p.103 / Chapter 3.2.5 --- Evaluation of antioxidant activity --- p.104 / Chapter 3.2.5.1 --- ABTS radical cation scavenging activity --- p.104 / Chapter 3.2.5.2 --- DPPH radical scavenging capacity --- p.105 / Chapter 3.2.5.3 --- Ferric Reducing Antioxidant Power --- p.106 / Chapter 3.2.5.4 --- β-carotene bleaching assay --- p.107 / Chapter 3.2.5.5 --- Hydroxyl radical scavenging activity --- p.108 / Chapter 3.2.6 --- Statistical analysis --- p.109 / Chapter 3.3 --- Results and Discussion --- p.110 / Chapter 3.3.1 --- Proximate analysis --- p.111 / Chapter 3.3.2 --- Total phenolic content --- p.112 / Chapter 3.3.3 --- Antioxidant activities --- p.114 / Chapter 3.3.3.1 --- ABTS radical cation scavenging activity --- p.114 / Chapter 3.3.3.2 --- DPPH radical scavenging capacity --- p.115 / Chapter 3.3.3.3 --- Ferric Reducing Antioxidant Power --- p.120 / Chapter 3.3.3.4 --- β-carotene bleaching assay --- p.121 / Chapter 3.3.3.5 --- Hydroxyl radical scavenging activity --- p.124 / Chapter 3.4 --- Correlation between antioxidant activities and total phenolic content --- p.127 / Chapter 3.5 --- Summary --- p.128 / Chapter Chapter 4: --- Effect of thermal processing on mushroom antioxidants --- p.131 / Chapter 4.1 --- Introduction --- p.131 / Chapter 4.1.1 --- General procedures of thermal processing on mushrooms --- p.131 / Chapter 4.1.1.1 --- Canning --- p.136 / Chapter 4.1.1.2 --- Drying --- p.136 / Chapter 4.1.2 --- Previous studies on the effect of thermal processing on mushroom antioxidants --- p.136 / Chapter 4.2 --- Materials and methods --- p.140 / Chapter 4.2.1 --- Thermal processing --- p.140 / Chapter 4.2.1.1 --- Canning --- p.140 / Chapter 4.2.1.2 --- Drying --- p.143 / Chapter 4.2.2 --- Sample preparation --- p.144 / Chapter 4.2.3 --- Sample extraction --- p.145 / Chapter 4.2.4 --- Evaluation of antioxidant activity --- p.145 / Chapter 4.2.5 --- Total phenolic content --- p.146 / Chapter 4.2.6 --- Measurement of Hydromethylfurfural (HMF) --- p.146 / Chapter 4.2.7 --- Statistical analysis --- p.147 / Chapter 4.3 --- Results --- p.148 / Chapter 4.3.1 --- ABTS radical cation scavenging activity --- p.148 / Chapter 4.3.1.1 --- Canning --- p.148 / Chapter 4.3.1.1.1 --- Effect of blanching --- p.148 / Chapter 4.3.1.1.2 --- Effect of sterilization time --- p.149 / Chapter 4.3.1.1.3 --- Effect of addition of vitamin C --- p.149 / Chapter 4.3.1.1.4 --- Effect of storage --- p.151 / Chapter 4.3.1.2 --- Drying --- p.151 / Chapter 4.3.1.2.1 --- Effect of blanching --- p.152 / Chapter 4.3.1.2.2 --- Effect of drying time --- p.153 / Chapter 4.3.1.2.3 --- Effect of drying temperature --- p.154 / Chapter 4.3.1.2.4 --- Effect of storage --- p.155 / Chapter 4.3.2 --- Ferric Reducing Antioxidant Power --- p.165 / Chapter 4.3.2.1 --- Canning --- p.165 / Chapter 4.3.2.1.1 --- Effect of blanching --- p.165 / Chapter 4.3.2.1.2 --- Effect of sterilization time --- p.166 / Chapter 4.3.2.1.3 --- Effect of addition of vitamin C --- p.167 / Chapter 4.3.2.1.4 --- Effect of storage --- p.168 / Chapter 4.3.2.2 --- Drying --- p.169 / Chapter 4.3.2.2.1 --- Effect of blanching --- p.170 / Chapter 4.3.2.2.2 --- Effect of drying time --- p.171 / Chapter 4.3.2.2.3 --- Effect of drying temperature --- p.172 / Chapter 4.3.2.2.4 --- Effect of storage --- p.173 / Chapter 4.3.3 --- β-carotene bleaching assay --- p.182 / Chapter 4.3.3.1 --- Canning --- p.182 / Chapter 4.3.3.1.1 --- Effect of blanching --- p.183 / Chapter 4.3.3.1.2 --- Effect of sterilization time --- p.183 / Chapter 4.3.3.1.3 --- Effect of addition of vitamin C --- p.184 / Chapter 4.3.3.1.4 --- Effect of storage --- p.184 / Chapter 4.3.3.2 --- Drying --- p.185 / Chapter 4.3.3.2.1 --- Effect of blanching --- p.186 / Chapter 4.3.3.2.2 --- Effect of drying time --- p.187 / Chapter 4.3.3.2.3 --- Effect of drying temperature --- p.188 / Chapter 4.3.3.2.4 --- Effect of storage --- p.189 / Chapter 4.3.4 --- Hydroxyl radical scavenging activity --- p.198 / Chapter 4.3.4.1 --- Canning --- p.198 / Chapter 4.3.4.1.1 --- Effect of blanching --- p.198 / Chapter 4.3.4.1.2 --- Effect of sterilization time --- p.199 / Chapter 4.3.4.1.3 --- Effect of addition of vitamin C --- p.200 / Chapter 4.3.4.1.4 --- Effect of storage --- p.201 / Chapter 4.3.4.2 --- Drying --- p.201 / Chapter 4.3.4.2.1 --- Effect of blanching --- p.202 / Chapter 4.3.4.2.2 --- Effect of drying time --- p.203 / Chapter 4.3.4.2.3 --- Effect of drying temperature --- p.203 / Chapter 4.3.4.2.4 --- Effect of storage --- p.204 / Chapter 4.3.5 --- Total phenolic content --- p.214 / Chapter 4.3.5.1 --- Canning --- p.214 / Chapter 4.3.5.1.1 --- Effect of blanching --- p.215 / Chapter 4.3.5.1.2 --- Effect of sterilization time --- p.217 / Chapter 4.3.5.1.3 --- Effect of addition of vitamin C --- p.218 / Chapter 4.3.5.1.4 --- Effect of storage --- p.219 / Chapter 4.3.5.2 --- Drying --- p.223 / Chapter 4.3.5.2.1 --- Effect of blanching --- p.223 / Chapter 4.3.5.2.2 --- Effect of drying time --- p.225 / Chapter 4.3.5.2.3 --- Effect of drying temperature --- p.226 / Chapter 4.3.5.2.4 --- Effect of storage --- p.227 / Chapter 4.3.6 --- The Hydroxymethylfurfural (HMF) content --- p.237 / Chapter 4.3.6.1 --- Canning --- p.237 / Chapter 4.3.6.1.1 --- Effect of blanching --- p.237 / Chapter 4.3.6.1.2 --- Effect of sterilization time --- p.238 / Chapter 4.3.6.1.3 --- Effect of addition of vitamin C --- p.238 / Chapter 4.3.6.1.4 --- Effect of storage --- p.239 / Chapter 4.3.6.2 --- Drying --- p.239 / Chapter 4.3.6.2.1 --- Effect of blanching --- p.239 / Chapter 4.3.6.2.2 --- Effect of drying time --- p.240 / Chapter 4.3.6.2.3 --- Effect of drying temperature --- p.241 / Chapter 4.3.6.2.4 --- Effect of storage --- p.242 / Chapter 4.4 --- Summary --- p.249 / Chapter 4.5 --- Discussion --- p.257 / Chapter 4.5.1 --- Reduction of antioxidant activities in mushrooms by heat treatment --- p.257 / Chapter 4.5.2 --- Effect of blanching --- p.259 / Chapter 4.5.3 --- Effect of sterilization time --- p.260 / Chapter 4.5.4 --- Effect of drying time and temperature --- p.262 / Chapter 4.5.5 --- Effect of addition of vitamin C --- p.263 / Chapter 4.5.6 --- Changes during storage --- p.265 / Chapter 4.5.7 --- Difference in canning and drying --- p.269 / Chapter Chapter 5: --- Conclusions --- p.275 / References --- p.280

Identiferoai:union.ndltd.org:cuhk.edu.hk/oai:cuhk-dr:cuhk_325671
Date January 2006
ContributorsMa, Yam Tak., Chinese University of Hong Kong Graduate School. Division of Food and Nutritional Sciences.
Source SetsThe Chinese University of Hong Kong
LanguageEnglish, Chinese
Detected LanguageEnglish
TypeText, bibliography
Formatprint, xxix, 300 leaves : ill. (some col.) ; 30 cm.
RightsUse of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/)

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