Handbook of Food Analytical Chemistry, Volumes 1 and 2

Ronald E. Wrolstad, PhD,?is a Distinguised Professor in the Department of Food Science & Technology at Oregon State University. Eric A. Decker, PbD,?is a Professor in the Department of Food Science at the University of Massachusetts, Amherst. He is an author, with Cameron Faustman and Clemente J. Lopez-Bote of Antioxidants in Muscle Foods: Nutritional Strategies to Improve Quality, also published by Wiley. Steven J. Schwartz, PhD,?is a Professor in the Department of Food Science & Technology at The Ohio State University. Peter Sporns, PhD,?is a Professor in the Department of Agricultural, Food, and Nutritional Science and is the Associate Chair of the graduate program in that department at the University of Alberta, Canada.

Preface ix

Foreword to Current Protocols in Food Analytical Chemistry xi

Contributors xiii

A WATER

A1 Gravimetric Measurements of Water

A1.1 Gravimetric Determination of Water by Drying and Weighing

A1.2 Karl Fischer Titration

A1.3 Application of Low-Resolution NMR for Simultaneous Moisture and Oil Determination in Food (Oilseeds)

A1.4 Traditional Indirect Methods for Estimation of Water Content: Measurement of oBrix

A2 Vapor Pressure Measurements of Water

A2.1 Factors to Consider When Estimating Water Vapor Pressure

A2.2 Dew-Point Method for the Determination of Water Activity

A2.3 Measurement of Water Activity Using Isopiestic Method

A2.4 Direct Manometric Determination of Vapor Pressure

A2.5 Measurement of Water Activity by Electronic Sensors

B PROTEINS

B1 Measurement of Protein Content

B1.1 The Colorimetric Detection and Quantitation of Total Protein

B1.2 Determination of Total Nitrogen

B1.3 Spectrophotometric Determination of Protein ConcentrationB2 Biochemical Compositional Analyses of Proteins

B2.1 Analyses of Protein Quality

B2.2 Evaluation of the Progress of Protein Hydrolysis

B3 Characterization of Proteins

B3.1 Electrophoresis Analysis

B3.2 Electroblotting from Polyacrylamide Gels

B3.3 Detection of Proteins on Blot Membranes

B3.4 Immunoblot Detection

B3.5 Determining the CD Spectrum of a Protein

B3.6 Determining the Fluorescence Spectrum of a Protein

B4 Purification of Proteins

B4.1 Overview of Protein Purification and Characterization

B4.2 Overview of Conventional ChromatographyB5 Functionality of Proteins

B.5.1 Measurement of Functional Properties: Overview of Protein Functionality Testing

B 5.2 Measurement of Protein Hydrophobicity

B 5.3 Water Retention Properties of Solid Foods

C ENZYMES

C1 Strategies for Enzyme Activity Measurements

C1.1 Expression and Measurement of Enzyme Activity

C1.2 Detecting Enzyme Activity: A Case Study of Polygalacturonase

C2 Proteolytic Enzymes

C2.1 Activity Measurements of Proteinases Using Synthetic Substrates

C2.2 Peptidase Activity Assays Using Protein Substrates

C3 Lipolytic EnzymesC3.1 Lipase Assays

C4 Oxidoreductases

C4.1 Polarographic and Spectrophotometric Assay of Diphenol Oxidases (Polyphenol Oxidase)

C4.2 Analysis of Lipoxygenase Activity and Products

D LIPIDS

D1 Lipid Composition

D1.1 Extraction and Measurement of Total Lipids

D1.2 Analysis of Fatty Acids in Food Lipids

D1.3 Cholesterol

D1.4 Oil Quality Indices

D1.5 Analysis of Tocopherols and Tocotrienols

D1.6 Quantitation of Lipid Classes by Thin-Layer Chromatography with Flame Ionization Detection

D1.7 Infrared Spectroscopic Determination of Total Trans Fatty Acids