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Effects of lipase supplementation and salt replacement on the chemical, microbiological and organoleptic qualities of white Chinese fermented beancurd.

Chang Pui Sze. / Thesis submitted in: October 2004. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 204-227). / Abstracts in English and Chinese. / Acknowledgement --- p.i / Abstract (In English) --- p.ii / Abstract (In Chinese) --- p.iv / List of Tables --- p.vi / List of Figures --- p.x / Contents --- p.xii / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Historical Background of Sufu --- p.1 / Chapter 1.2 --- Nutritional Benefits of Sufu --- p.2 / Chapter 1.3 --- Production Steps --- p.2 / Chapter 1.3.1 --- Preparation of Tofu --- p.5 / Chapter 1.3.2 --- Preparation of Pehtze --- p.5 / Chapter 1.3.3 --- Salting or Brining --- p.8 / Chapter 1.3.4 --- Aging --- p.9 / Chapter 1.4 --- Local Varieties of Sufu --- p.9 / Chapter 1.5 --- Other Types of Sufu Fermentation --- p.10 / Chapter 1.6 --- Biochemical Changes during Sufu Production --- p.11 / Chapter 1.6.1 --- Protein Faction --- p.12 / Chapter 1.6.2 --- Lipid Fraction --- p.14 / Chapter 1.6.3 --- Carbohydrate fraction --- p.14 / Chapter 1.7 --- Sufu Flavor --- p.14 / Chapter 1.7.1 --- "Water-soluble Peptides, Free Amino Acids and Tasty Oligopeptides" --- p.14 / Chapter 1.7.2 --- Nucleotide Contents in the Taste of Sufu --- p.15 / Chapter 1.7.3 --- Effects of Ethanol on Flavor Development --- p.15 / Chapter 1.7.4 --- Volatile Components in Sufu --- p.16 / Chapter 1.8 --- Microbiological Safety of Sufu --- p.18 / Chapter 1.9 --- Existing Problems in Sufu Production --- p.19 / Chapter 1.10 --- Acceleration of Sufu Maturation by Adding Exogenous Lipase --- p.20 / Chapter 1.10.1 --- Proteases --- p.22 / Chapter 1.10.2 --- Problems with Proteases --- p.24 / Chapter 1.10.3 --- Lipases --- p.25 / Chapter 1.10.4 --- Problems with Lipases --- p.26 / Chapter 1.11 --- Replacement of Sodium Salt in Food with Alternative Salts --- p.29 / Chapter 1.12 --- Objectives --- p.33 / Chapter 2 --- Development of Volatile Compounds in Sufu --- p.35 / Chapter 2.1 --- Introduction --- p.35 / Chapter 2.2 --- Materials and Method --- p.36 / Chapter 2.2.1 --- Sufu Production --- p.36 / Chapter 2.2.1.1 --- Preparation of Tofu --- p.36 / Chapter 2.2.1.2 --- Inoculation of Tofu --- p.37 / Chapter 2.2.1.2.1 --- The Mold Strain --- p.37 / Chapter 2.2.1.2.2 --- Spore Suspension --- p.38 / Chapter 2.2.1.2.3 --- Spore Count in Spore Suspension --- p.38 / Chapter 2.2.1.3 --- Preparation of Pehtze --- p.39 / Chapter 2.2.1.4 --- Brining and Aging --- p.41 / Chapter 2.2.2 --- Sampling of Sufu --- p.42 / Chapter 2.2.3 --- Flavor Analysis --- p.42 / Chapter 2.2.3.1 --- Simultaneous Steam Distillation-Solvent Extraction (SDE) --- p.42 / Chapter 2.2.3.2 --- Gas chromatography-mass spectrometry (GC-MS) Conditions --- p.43 / Chapter 2.2.3.3 --- Compound Identification and Quantification --- p.44 / Chapter 2.3 --- Results --- p.45 / Chapter 2.3.1 --- Evolution of Volatiles During Sufu Aging --- p.45 / Chapter 2.3.1.1 --- Esters --- p.46 / Chapter 2.3.1.2 --- Alcohols --- p.51 / Chapter 2.3.1.3 --- Aldehydes --- p.55 / Chapter 2.3.1.4 --- Ketones --- p.55 / Chapter 2.3.1.5 --- Other Nitrogen-containing Compounds --- p.59 / Chapter 2.3.1.6 --- Sulfur (S)-containing and Oxygen (O)-containing Compounds --- p.51 / Chapter 2.3.1.7 --- Pyrazines --- p.61 / Chapter 2.3.1.8 --- Miscellaneous Compounds --- p.63 / Chapter 2.3.2 --- Change in the Concentrations of Sufu Odorous Compounds with Time --- p.65 / Chapter 2.4 --- Discussion --- p.67 / Chapter 2.4.1 --- Quantitatively Important Volatile Components of Sufu --- p.67 / Chapter 2.4.2 --- Esters --- p.59 / Chapter 2.4.3 --- Alcohols --- p.72 / Chapter 2.4.3.1 --- 1-Hexanol --- p.72 / Chapter 2.4.3.2 --- Phenol and 2-Methoxyphenol --- p.74 / Chapter 2.4.4 --- Aldehydes --- p.75 / Chapter 2.4.4.1 --- Hexanal --- p.75 / Chapter 2.4.4.2 --- "(E,E)-2,4-Heptadienal" --- p.77 / Chapter 2.4.4.3 --- (E)-2-Heptenal --- p.78 / Chapter 2.4.4.4 --- Benzeneacetaldehyde --- p.79 / Chapter 2.4.5 --- Ketones --- p.80 / Chapter 2.4.5.1 --- 3-Hydroxy-2-Butanone --- p.81 / Chapter 2.4.6 --- Sulfur-Containing Compounds --- p.82 / Chapter 2.4.6.1 --- 3-(Methylthio)propanal --- p.82 / Chapter 2.4.7 --- Pentylfuran --- p.84 / Chapter 2.4.8 --- Naphthalene --- p.86 / Chapter 2.4.9 --- Contaminants and artifacts generated by A-SDE --- p.87 / Chapter 2.5 --- Conclusion --- p.92 / Chapter 3 --- Acceleration of Sufu Production with Exogenous Lipase Effect on Flavor Development --- p.95 / Chapter 3.1 --- Introduction --- p.95 / Chapter 3.2 --- Materials and Method --- p.96 / Chapter 3.2.1 --- Sufu Production --- p.96 / Chapter 3.2.2 --- The Addition of Lipases --- p.96 / Chapter 3.2.3 --- Sampling of Sufu --- p.97 / Chapter 3.2.4 --- Flavor Analysis --- p.97 / Chapter 3.2.5 --- Statistical Analysis of Sufu Flavor Compounds --- p.98 / Chapter 3.2.6 --- Proximate Analysis --- p.98 / Chapter 3.2.7 --- Freeze-Drying --- p.99 / Chapter 3.2.8 --- Statistical Analysis of Sufu Proximate Contents --- p.99 / Chapter 3.2.9 --- Sensory Evaluation of Experimental Sufu --- p.100 / Chapter 3.3 --- Results --- p.102 / Chapter 3.3.1 --- Experiment I ´ؤ Adding 0.01% (w/w) Lipase from Porcine Pancreas and Candida rugosa --- p.102 / Chapter 3.3.1.1 --- Esters --- p.104 / Chapter 3.3.1.2 --- Alcohols --- p.108 / Chapter 3.3.1.3 --- Aldehydes --- p.110 / Chapter 3.3.1.4 --- 3-Hydroxy-2-Butanone --- p.113 / Chapter 3.3.1.5 --- 3-(Methylthio)propanal --- p.114 / Chapter 3.3.1.6 --- 2-Pentylfuran --- p.115 / Chapter 3.3.1.7 --- Naphthalene --- p.115 / Chapter 3.3.2 --- Experiment II - Adding 0.02% Lipase from Porcine Pancreas and Candida rugosa --- p.117 / Chapter 3.3.2.1 --- Esters --- p.118 / Chapter 3.3.2.2 --- Alcohols --- p.123 / Chapter 3.3.2.3 --- Aldehydes --- p.125 / Chapter 3.3.2.4 --- 3-Hydroxy-2 -Butanone --- p.129 / Chapter 3.3.2.5 --- 3-(Methylthio)propanal --- p.129 / Chapter 3.3.2.6 --- 2-Pentylfuran --- p.131 / Chapter 3.3.2.7 --- Naphthalene --- p.131 / Chapter 3.3.3 --- Sensory Evaluation of Lipase-treated Sufu --- p.132 / Chapter 3.3.4 --- Proximate Composition of Sufu at Different Ages from the 3 Treatments --- p.134 / Chapter 3.3.4.1 --- Addition of 0.01%(w/w) Lipase to Sufu Aging Solution --- p.134 / Chapter 3.3.4.1.1 --- Crude Protein --- p.134 / Chapter 3.3.4.1.2 --- Crude Lipid --- p.135 / Chapter 3.3.4.1.3 --- Moisture --- p.138 / Chapter 3.3.4.1.4 --- Ash --- p.138 / Chapter 3.3.4.2 --- Addition of 0.02% (w/w) Lipase to Sufu Aging Solution --- p.141 / Chapter 3.3.4.2.1 --- Crude Protein --- p.141 / Chapter 3.3.4.2.2 --- Crude Lipid --- p.141 / Chapter 3.3.4.2.3 --- Moisture --- p.144 / Chapter 3.3.4.2.4 --- Ash --- p.144 / Chapter 3.4 --- Discussion --- p.147 / Chapter 3.4.1 --- Adding 0.01 % Lipase from Porcine Pancreas and Candida rugosa --- p.147 / Chapter 3.4.1.1 --- Comparison of Total Odorous Content --- p.147 / Chapter 3.4.1.2 --- Sensory Evaluation of Experimental Sufu --- p.147 / Chapter 3.4.2 --- Adding 0.02% Lipase from Porcine Pancreas and Candida rugosai --- p.150 / Chapter 3.4.2.1 --- Comparison of Total Odorous Content --- p.150 / Chapter 3.4.2.2 --- Sensory Evaluation of Experimental Sufu --- p.151 / Chapter 3.4.3 --- Summary of Sensory and TOC Results of Lipase Experiments --- p.153 / Chapter 3.4.4 --- Impact of Lipase Addition on Different Odorous Volatile Compounds --- p.153 / Chapter 3.4.4.1 --- Esters --- p.154 / Chapter 3.4.4.2 --- Alcohols --- p.155 / Chapter 3.4.4.3 --- Aldehydes --- p.157 / Chapter 3.4.4.4 --- 3-Hydroxy-2-Butanone --- p.159 / Chapter 3.4.4.5 --- 3-(Methylthio)propanal --- p.160 / Chapter 3.4.4.6 --- 2-Pentylfuran and Naphthalene --- p.161 / Chapter 3.4.5 --- Effect of Aging on Chemical Composition of Sufu --- p.161 / Chapter 3.4.5.1 --- Crude Protein --- p.161 / Chapter 3.4.5.2 --- Crude Lipid --- p.162 / Chapter 3.4.5.3 --- Ash --- p.163 / Chapter 3.4.6 --- Effect of Lipase Addition on Chemical Composition of Sufu --- p.163 / Chapter 3.4.7 --- Effect of Lipase Addition on Free Fatty Acid (FFA) Profiles --- p.164 / Chapter 3.4.8 --- Generation of Different Classes of Esters from Animal and Fungal Lipases --- p.168 / Chapter 3.5 --- Conclusion --- p.171 / Chapter 4 --- "Partial Substitution of Sodium Chloride with Potassium Chloride in Sufu Aging Solution - Effect on Proteolysis, Bacterial Growth and Flavor" --- p.174 / Chapter 4.1 --- Introduction --- p.174 / Chapter 4.2 --- Materials and Method --- p.175 / Chapter 4.2.1 --- Sufu Production --- p.175 / Chapter 4.2.2 --- Partial Substitution of NaCl with KC1 --- p.176 / Chapter 4.2.3 --- Sampling of Sufu --- p.176 / Chapter 4.2.4 --- Bacterial Count --- p.176 / Chapter 4.2.5 --- Total and Amino Nitrogen Contents in Sufu --- p.177 / Chapter 4.2.6 --- Sensory Evaluation of Experimental Sufu --- p.177 / Chapter 4.3 --- Results --- p.179 / Chapter 4.3.1 --- Microbial Growth --- p.179 / Chapter 4.3.2 --- Proteolysis --- p.181 / Chapter 4.3.2.1 --- Total Nitrogen Content (TN) --- p.181 / Chapter 4.3.2.2 --- Amino Nitrogen Content (AN) --- p.184 / Chapter 4.3.3 --- Sensory Evalutaion of Control and KCl-Substituted Sufu --- p.186 / Chapter 4.4 --- Discussion --- p.187 / Chapter 4.4.1 --- Microbial Growth --- p.187 / Chapter 4.4.2 --- Proteolysis --- p.189 / Chapter 4.4.3 --- Sensory Tests --- p.194 / Chapter 4.5 --- Conclusion --- p.198 / Chapter 5 --- Overal Conclusion --- p.199 / References --- p.204 / Appendix I --- p.228 / Appendix II --- p.229

Identiferoai:union.ndltd.org:cuhk.edu.hk/oai:cuhk-dr:cuhk_325170
Date January 2005
ContributorsChang, Pui Sze., 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, xviii, 229 leaves : ill. ; 30 cm.
CoverageChina
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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