The food chemistry laboratory : a manual for experimental foods, dietetics, and food scientists /

Table of Contents
1. Literature Search
........................................................................................................................1
Abstracts and Indexes...................................................................................................................1
Journals..........................................................................................................................................1
Advances and Reviews .................................................................................................................1
General ..........................................................................................................................................2
Internet Sources of Information ...................................................................................................2
2. Evaluation of Foods
...................................................................................................................5
Color ..............................................................................................................................................5
Texture...........................................................................................................................................6
Flavor .............................................................................................................................................6
3. Objective Methods
......................................................................................................................9
4. Sensory Methods
......................................................................................................................11
Developing Forms for Sensory Tests .........................................................................................12
5. Laboratory Notebook
..............................................................................................................15
Format..........................................................................................................................................15
Sample Tables as Reported in the
Journal of Food Science
.....................................................16
Graphs from the
Journal of Food Science
..................................................................................18
6. Style Guide for Research Papers
...........................................................................................21
Mission of IFT Scientific Journals ...............................................................................................21
General Editorial Policies ...........................................................................................................21
Journal Sections...........................................................................................................................23
Manuscript Requirements ...........................................................................................................24
Reference Format ........................................................................................................................26
Editorial Review and Processing ................................................................................................27
Instructions for Submitting a Manuscript...................................................................................28
Presubmission Checklist .............................................................................................................29
7. Individual Project
.....................................................................................................................31
Research Proposal.......................................................................................................................31
Oral Presentation ........................................................................................................................31
Written Presentation....................................................................................................................32
Scorecard for Grade....................................................................................................................34
8. Laboratory: Sensory Evaluation of Foods
...........................................................................35
Experiment 1: Threshold Concentrations of the Primary Tastes ..............................................35
Experiment 2: Effect of Temperature on Taste .........................................................................35
Experiment 3: Perception of Phenylthiocarbamide (PTC)........................................................36
Experiment 4: Comparison of Sweetness of Sugars..................................................................36
Experiment 5: Identification of Samples....................................................................................37
Experiment 6A: Difference Testing ............................................................................................38
Experiment 6B: Descriptive Tests ..............................................................................................39
Experiment 6C: Affective Tests...................................................................................................39
Experiment 7: Adaptation of Receptors.....................................................................................40
9. Laboratory: Objective Evaluation of Foods
.........................................................................41
Texture.........................................................................................................................................41
10. Laboratory: Physical Properties of Foods
...........................................................................43
Water Activity ..............................................................................................................................43
Viscosity.......................................................................................................................................43
Specific Gravity ...........................................................................................................................44
Experiment 1: Water Activity......................................................................................................44
Experiment 2: Viscosity ..............................................................................................................46
Experiment 3: Specific Gravity and Refractive Index................................................................46
11. Laboratory: Dispersion of Matter
.........................................................................................49
Experiment 1: Solutions..............................................................................................................49
Experiment 2: Emulsions ............................................................................................................51
Experiment 3: Foaming Properties of Proteins..........................................................................53
12. Laboratory: Lipids
....................................................................................................................55
Experiment 1: Odors and Physical State of Lipids and Fatty Acids .........................................55
Experiment 2: Solubility, Specific Gravity, and Refractive Index .............................................56
Experiment 3: Water-Absorbing Capacity..................................................................................57
Experiment 4: Plasticity of Fats ..................................................................................................57
Experiment 5: Fat Bloom in Chocolate......................................................................................58
Experiment 6: Oxidative Rancidity.............................................................................................59
13. Laboratory: Amino Acids, Proteins, and Maillard Browning
..........................................61
Experiment 1: Maillard Reaction ................................................................................................61
Experiment 2: Qualitative Test for Protein ................................................................................62
Experiment 3: Quantitative Determination of Protein in Foods by the Biuret Method ..........64
Experiment 4: Effect of Heat on Proteins ..................................................................................65
Experiment 5: Coagulation of Proteins ......................................................................................66
Experiment 6: Effect of pH on Hydration of Meat Proteins .....................................................67
Experiment 7: Spun Fiber Production........................................................................................68
Experiment 8: Effects of the Enzyme Rennin on Milk Protein .................................................68
14. Laboratory: Gelatin
..................................................................................................................71
Experiment 1: Effects of Variations in Gelatin Concentration, pH, Sucrose Concentration,
and Presence of a Proteolytic Enzyme on Gelatin Gel Strength ........................................71
Experiment 2: Effect of
In Situ
Enzymes on Gelatin Gel Strength...........................................73
15. Laboratory: Carbohydrates
....................................................................................................75
Experiment 1: Fehling’s Test for Reducing Sugars....................................................................75
Experiment 2: Microscopic Appearance of Starch ....................................................................76
Experiment 3: Starch Gels ..........................................................................................................77
Experiment 4: Viscosity Curves of Starch Pastes.......................................................................78
16. Laboratory: Flour Mixtures
....................................................................................................81
Experiment 1: Gluten Balls.........................................................................................................81
Experiment 2: Sugar Cookies .....................................................................................................82
Experiment 3: Chocolate Cakes .................................................................................................84
17. Laboratory: Pigments
..............................................................................................................87
Experiment 1: Color Reactions of Myoglobin............................................................................87
Experiment 2: The Effects of Heat and pH on Plant Pigments ................................................88
Experiment 3: Separation of Pigments in a Green, Leafy Vegetable .......................................90
Experiment 4: Enzymatic Browning...........................................................................................92
Experiment 5: Peroxidase Assay to Determine Adequacy of Blanching .................................93
Experiment 6: Measurement of Color of Oranges ....................................................................94
18. Laboratory: Pectin
....................................................................................................................97
Experiment 1: Histochemical Localization of Pectic Substances ..............................................97
Experiment 2: Pectin Gels ..........................................................................................................98
19. Laboratory: Synthesized Carbohydrate Food Gums
........................................................ 103
Experiment 1: Dispersibility and Thermogelation of Cellulose Gums................................... 103
Experiment 2: Alginate Gels..................................................................................................... 105
20. Equipment Guide
................................................................................................................... 107
Brookfield Viscometer (Analog and Digital) ........................................................................... 107
Compensating Polar Planimeter ............................................................................................... 109
Consistometer (Bostwick)......................................................................................................... 110
Hunter Colorimeter ................................................................................................................... 111
Hydrometer ............................................................................................................................... 112
Instron Materials Tester ............................................................................................................ 114
Jelmeter...................................................................................................................................... 115
Linespread Apparatus ............................................................................................................... 116
Penetrometer or Compressometer ........................................................................................... 117
pH Meter.................................................................................................................................... 118
Reflectance Meter (Photovolt) .................................................................................................. 120
Refractometer (Abbe)................................................................................................................ 121
Seed Volume Apparatus ........................................................................................................... 123
Shear Press ................................................................................................................................ 124
Shortometer ............................................................................................................................... 125
Specific Gravity of Solids.......................................................................................................... 126
Spectrophotometer.................................................................................................................... 126
Stable Micro Systems Texture Analyzer ................................................................................... 127
Vernier Caliper .......................................................................................................................... 129
Visco/Amylo/GRAPH................................................................................................................ 130
Water Activity System ............................................................................................................... 131
Appendix
................................................................................................... 133
Index
................................................................................................................................................ 135