Title Page

Contents

Abstract 14

Ⅰ. INTRODUCTION 17

Ⅱ. Literature Review 21

1. Ginseng 21

2. Air Impingement Fluidization Bed Roasting 24

3. Energy Drink 26

A. Energy Drink Origin and Industry 26

B. Energy Drink Composition 28

4. Sensory analysis 32

A. Threshold Value 32

B. Descriptive Analysis 34

C. Consumer Test 36

Ⅲ. Bitterness of Roasted Ginseng Powder and Descriptive Analysis of Model Energy Drink using Ginseng Powder and Caffeine 40

1. Abstract 40

2. Materials and Methods 42

A. Preparation of Ginseng Powder 42

B. Model Energy Drink Preparation 44

C. Focus Group Interview 47

D. Panel Selection and Training 49

E. Threshold measurements using the method of limits 54

F. Threshold Data Analysis 56

G. Descriptive Analysis 56

H. Statistical Analysis 62

3. Results and Discussion 63

A. Focus Group Interview Content Analysis 63

B. Panel training 75

C. Bitterness Perception of Roasted Ginseng Powder by Threshold Value 83

D. Descriptive analysis 87

4. Conclusion 99

Ⅳ. Sensory profile of energy drink with varying levels of roasted ginseng powder 101

1. Abstract 101

2. Materials and Method 103

A. Energy Drink Preparation 103

B. Physicochemical Analysis of Energy Drink Samples 106

C. Descriptive analysis 109

D. Consumer Acceptance Test 115

E. Statistical Analysis 116

3. Result and Discussion 117

A. Physicochemical Properties 117

B. Descriptive analysis of Energy Drinks 129

C. Consumer acceptance test 136

4. Conclusion 142

REFERENCES 144

ABSTRACT IN KOREAN 166

Appendix. Questionnaire for FGI (focus group interview) 169

Table 1. Overview of sensory evaluation techniques 38

Table 2. Amount of key compounds (caffeine, roasted ginseng powder, dried ginseng powder) in 100 mL model energy drink, L＝low, M=medium and H＝high levels 46

Table 3. Reference solutions and their modified on 100-point rating scales 52

Table 4. Terms, their definitions, references used to explain sensory terms, and rating anchors of the descriptive attributes for the model energy drink samples 60

Table 5. Sensory descriptors for ginseng powder 71

Table 6. Characteristics of focus group interview participants 74

Table 7. ANOVA of the data collected on reference solutions and intensity levels of each solutions taste attributes. 79

Table 8. Mean intensity ratings of sensory attributes of varying levels of ginseng by trained panel (n＝12) 91

Table 9. Mean intensity ratings of sensory attributes of varying levels of caffeine by trained panel (n＝12) 92

Table 10. Correlation analysis of sensory properties in a trained panel (n＝12) of 18 combinations of ingredients in model energy drink samples. The bolded values are significant at p ＜ 0.05 94

Table 11. Amount of ginseng powder in 100 mL energy drink, L＝low, M＝medium and H＝high levels 105

Table 12. Terms, their definitions, references used to explain sensory terms, and rating anchors of the descriptive attributes for the 6 energy drinks 112

Table 13. Color change in energy drinks with different levels of roasted ginseng powder or dried ginseng powder 119

Table 14. The physicochemical parameters of energy drinks containing roasted ginseng powder or dried ginseng powder 123

Table 15. Mean intensity ratings of sensory attributes of 6 developed energy drinks by trained panel (n＝12) 132

Table 16. Consumer acceptance, purchase intent and recommend intent of 6 energy drinks by 79 consumers 137

Fig. 1. Diamonds indicate the perceived concentration of caffeine solutions, and dashed lines reveal the 95% confidence interval. 82

Fig. 2. Group best estimate threshold (GBET) for different threshold types [detection-D, recognition-R] of in (A) water... 86

Fig. 3. Principal component analysis biplot of mean intensity of 16 sensory attributes in model energy drink samples. 98

Fig. 4. Photograph of energy drinks containing roasted ginseng powder or dried ginseng powder. 119

Fig. 5. The percentage DPPH radical scavenging of EDs prepared RGP and DGP by three levels. 128

Fig. 6. The total phenolic content of EDs prepared RGP and DGP by three levels. 128

Fig. 7. Principal component analysis biplot of mean intensity of 21 sensory attributes in 6 energy drinks. 135

Fig. 8. Partial least square regression on 6 energy drinks of descriptive attributes with 3 levels of roasted ginseng powder or... 140

Fig. 9. Variable importance in the projection (VIP) of 21 descriptive sensory attributes by partial least square regression. 141