ACKNOWLEDGMENTS
Special thanks go to my major advisor, Dr. Denise Brochetti, for her patience,
understanding, guidance, and most of all the encouragement she has given me during my graduate
studies. I would also like to thank committee members Dr. Susan E. Duncan and Dr. William E.
Barbeau for their advice, encouragement and support.
I would like to thank Carolyn Harris, Department of Human Nutrition, Foods and
Exercise, for her technical guidance, patience and extra hours she put in throughout the study. I
would also like to thank Dr. Klaus Hinkelmann and Dr. Peter Ammerman for their assistance
with the statistical analyses.
I would like to thank Dairy Management Inc., Chicago, IL, for funding for the project.
Special thanks go to all the sensory panelists for their participation in this study and to Tracy
Sutton for her assistance with the sensory testing.
Very special thanks go to my parents, Zhuo-Rong Wu and Jing-Xian Hou, for their love,
understanding and financial support during my graduate studies in the U.S. I would also like to
thank my friends, Maria Uyrio, Maryam Majadi, Kimberley Hart, Alice Zhou and Quinn Zuo,
for their love, advice and encouragement during my graduate studies.
iii
TABLE OF CONTENTS
CHAPTER
I.
II.
III.
IV.
PAGE
INTRODUCTION.............................................................................
REVIEW OF LITERATURE.............................................................
1.
Lactose Intolerance.................................................................
2.
Lactose-Reduced Milk............................................................
3.
Baked Custard.........................................................................
4.
Low Fat, Low Cholesterol Egg Yolk as an Egg Substitute......
5.
Nutrition and the Elderly........................................................
EXPERIMENT I: QUALITY OF A DESSERT TYPE LACTOSEREDUCED BAKED CUSTARD
1.
Introduction.............................................................................
2.
Materials and Methods...........................................................
Baked Custard Formulations and Preparation.........................
Chemical Analyses..................................................................
Physical Analyses...................................................................
Sensory Evaluation: Descriptive Analysis..............................
Experimental Design and Statistical Analyses........................
Sensory Evaluation: Consumer Testing..................................
3.
Results and Discussion...........................................................
Composition...........................................................................
Physical Properties.................................................................
Sensory Characteristics...........................................................
Acceptability..........................................................................
4.
Conclusions.............................................................................
EXPERIMENT II: QUALITY OF AN ENTREE TYPE LACTOSEREDUCED BAKED CUSTARD
1.
Introduction............................................................................
2.
Material and Methods............................................................
Baked Custard Formulations and Preparation.........................
Chemical Analyses..................................................................
Physical Analyses..................................................................
Sensory Evaluation: Descriptive Analysis.............................
Experimental Design and Statistical Analyses........................
3.
Results and Discussion...........................................................
Composition...........................................................................
Physical Properties.................................................................
Sensory Characteristics...........................................................
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4
6
7
7
9
13
13
13
15
16
16
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21
21
23
29
31
35
36
36
36
36
36
38
38
38
38
44
49
CHAPTER
PAGE
4.
Conclusions..............................................................................
LIST OF REFERENCES.............................................................................................
APPENDIXES.............................................................................................................
A.
SPECIFICATIONS FOR DRIED EGG WHITE SOLIDS.................
B.
EFFECTS OF GUMS ON THE QUALITY OF LACTOSEREDUCED BAKED CUSTARD MADE WITH LOW-FAT,
LOW-CHOLESTEROL EGG YOLK SOLIDS..................................
C.
CONSENT FORMS USED IN DESCRIPTIVE ANALYSIS AND
CONSUMER TESTING....................................................................
D.
INSTRUCTION SHEET AND SCORECARD USED IN
DESCRIPTIVE ANALYSIS OF THE DESSERT TYPE
BAKED CUSTARDS.........................................................................
E.
SCORECARD USED IN CONSUMER TESTING OF THE
DESSERT TYPE BAKED CUSTARD..............................................
F.
TABLES OF INTERACTION MEANS FOR THE DESSERT
TYPE BAKED CUSTARDS (EXPERIMENT I)..............................
G.
SPECIFICATIONS FOR DRIED CHEDDAR CHEESE FLAVOR
POWDER............................................................................................
H.
INSTRUCTION SHEET AND SCORECARD USED IN
DESCRIPTIVE ANALYSIS OF THE ENTREE TYPE
BAKED CUSTARDS.........................................................................
I.
TABLES OF INTERACTION MEANS FOR THE ENTREE
TYPE BAKED CUSTARDS (EXPERIMENT II).............................
VITA............................................................................................................................
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84
86
89
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LIST OF TABLES
TABLE
PAGE
1-Recommended Dietary Allowance for persons ages 51 and older for
protein, calcium, phosphorus and vitamin D..............................................
2-Formulations for dessert type baked custards.............................................
3-Sensory terminology and reference standards for dessert type baked
custards........................................................................................................
4-Formulations for dessert type baked custard used in training of sensory
panelists.......................................................................................................
5-Means ± standard deviations for nutrient composition of dessert type
baked custard mixes......................................................................................
6-Means ± standard deviations for physical properties of dessert type
baked custards..............................................................................................
7-Means ± standard deviations for sensory characteristics of dessert type
baked custards..............................................................................................
8-Characteristics of young and elderly adults participating in consumer
testing...........................................................................................................
9-Formulations for entree type baked custards...............................................
10-Sensory terminology and reference standards for entree type baked
custards.........................................................................................................
11-Means ± standard deviations for nutrient composition of entree type
baked custard mixes......................................................................................
12-Means ± standard deviations for physical properties of entree type
baked custards...............................................................................................
13-Means ± standard deviations for sensory characteristics of entree type
baked custards...............................................................................................
14-Means ± standard deviations for color, gel strength, and syneresis of
baked custards evaluated in preliminary testing............................................
15-Interaction means ± standard deviations for nutrient composition of
dessert type baked custard mixes..................................................................
16-Interaction means ± standard deviations for physical properties of
dessert type baked custards...........................................................................
17-Interaction means ± standard deviations for sensory characteristics of
dessert type baked custards...........................................................................
18-Interaction means ± standard deviations for hedonic ratings of the
dessert type baked custards...........................................................................
19-Interaction means ± standard deviations for nutrient composition of
entree type baked custard mixes....................................................................
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33
37
39
43
46
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65
80
81
83
83
90
TABLE
PAGE
20-Interaction means ± standard deviations for physical properties of
entree type baked custards.............................................................................
21-Interaction means ± standard deviations for sensory characteristics of
entree type baked custards.............................................................................
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LIST OF FIGURES
FIGURE
PAGE
1-Interaction between type of milk and type of egg for Hunter "L" values
for top surface of dessert type baked custards..............................................
2-Interaction between type of milk and type of egg for Hunter "L" values
for bottom surface of dessert type baked custards........................................
3-Interaction between type of milk and type of egg for Hunter "b" values
for bottom surface of dessert type baked custards........................................
4-Interaction between type of milk and type of egg for graininess of
dessert type baked custards...........................................................................
5-Interaction between type of milk and type of egg for lactose
concentrations of entree type baked custard mixes........................................
6-Interaction between type of milk and type of egg for galactose
concentrations of entree type baked custard mixes........................................
7-Interaction between type of milk and type of egg for Hunter "L" values
for top surface of entree type baked custards................................................
8-Interaction between type of milk and type of egg for Hunter "a" values
for top surface of entree type baked custards................................................
9-Interaction between type of milk and type of egg for Hunter "a" values
for bottom surface of entree type baked custards..........................................
10-Interaction between type of milk and type of egg for Hunter "b" values
for bottom surface of entree type baked custards..........................................
11-Interaction between type of milk and type of egg for gel strength of
entree type baked custards.............................................................................
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