COFFEE PREFERENCE AMONG COLLEGE AGE

STUDENTSAndrew KennedyDr. LiLi ZyzakJudson University

PURPOSECollege students consume coffee drink a lot of coffee throughout the day

Sell coffee that students enjoy and a new market arises

Test coffees for chemical volatiles that correspond with like/dislike of students

Create coffee that meets the specific tastes of students and profits rise for coffee companies

CHARACTERISTICS OF COFFEEAshyBurnt/SmokyChemical/MedicinalChocolate-LikeCaramel

EarthyFruity/CitrusNuttySpicyWoody

PROCEDURES FOR STUDENT TESTING1. Pour ~30 mL of each type of coffee into separate cups labeled 1-6 for

each volunteer1) Panera Columbian Decaf2) Starbucks Blonde Roast3) Burger King Smooth Roast4) Starbucks Americano5) Dunkin Donuts Original Blend6) McDonalds Original McCafe

2. Have each volunteer read through definitions of tastes and aromas they will rate coffees on

3. Allow each taste tester time to smell, taste, and rate each coffee beverage on given characteristics

4. Have each volunteer fill out survey asking for background information

BACKGROUND QUESTIONS Age? How often do you drink coffee? When do you drink coffee? (breakfast, midday, etc.) Any specific preferences for what type of coffee you drink and from where? Caffeinated or decaffeinated? Milk, cream, sugar, or any other additions? Syrups such as caramel or vanilla etc.? Iced, hot, or frozen?

Pane

ra Deca

f

Starbu

cks Bl

onde

Burge

r King

Starbu

cks Am

erican

o

Dunkin

Donuts

McDon

alds

0123456789

10

52.8

1.8

6.45

6.2

Like/Dislike

Pane

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Starbu

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onde

Burge

r King

Starbu

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erican

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Dunkin

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McDon

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0123456789

10

3.25.4

7.6

3.6 3 3

Burnt/Smoky

MAIN RATINGS

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r King

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Dunkin

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McDon

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0

12

3

4

5

67

89

10

13

5.2

1.2 1 1.8

Spicy

EQUIPMENT22 mL Headspace VialSolid Phase Microextraction (SPME) fiberDB-5 30-meter GC column (5% phenyl and 95% methyl)Mass Spectrometer (6890 Gas Chromatograph with 5975 Mass Spectrometer from Agilent)

PROCEDURES FOR CHEMICAL TESTINGSamples were analyzed in triplicate 1. 2 g of coffee brew was placed in 22 mL headspace vial and extracted

with a Solid Phase Microextraction (SPME) fiber for 10 min at 35C 2. Place SPME fiber on a DB-5 30-meter GC column (5% phenyl and 95%

methyl)3. Detect chemical volatiles using:

1. Agilent 6890N Gas Chromatograph 2. Agilent 5975C Mass Spectrometer

4. Determine peak areas based on extracted ion chromatograms for each analyte

CHEMICALS TESTED FORAcetaldehyde- sugar degradation topnote: sweet aroma character. Typically highest in lighter roasted coffee with less burnt character dimethyl sulfide - Sulfury topnote - potential indicator for freshness of coffee character2-methylpropanal - sweet musty odor, sweet whiskey taste 2,5-dimethylfuran - component of caramelized sugarsPyridine - good marker for how dark the coffee was roasted; higher pyridine levels typically correlate with more "burnt" character aroma2-furanmethanol acetate - *decaffeination results in lower levels of this compound - as seen in data3-ethyl-2-hydroxy-2-cyclopenten-1-one: thermal degradation of ascorbic acidethyl guaiacol: smoky aromas

ACETALDEHYDEsugar degradation topnote: sweet aroma character. Typically highest in lighter roasted coffee with less burnt character

DIMETHYL SULFIDE Sulfury topnote - potential indicator for freshness of coffee character

2-METHYLPROPANAL sweet musty odor, sweet whiskey taste

2, 5-DIMETHYLFURAN component of caramelized sugars

PYRIDINE good marker for how dark the coffee was roasted; higher pyridine levels typically correlate with more "burnt" character aroma

2-FURANMETHANOL ACETATEdecaffeination results in lower levels of this compound

3-ETHYL-2-HYDROXY-2-CYCLOPENTEN-1-ONE

thermal degradation of ascorbic acid

ETHYL GUAIACOL smoky aromas

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Starbu

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de

Burger

King

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Dunkin

Donuts

McDon

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10

5

2.81.8

6.45

6.2

Like/Dislike

Caffeine

0

1

2

3

4

5

6

7

8

9

10

5

2.8

1.8

6.4

5

6.2

Like/Dislike

Darker Roast

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10

3.25.4

7.6

3.6 3 3

Burnt/Smoky

higher pyridine levels typically correlate with more "burnt" character aroma

CONCLUSION Create coffee with medium amounts of caffeine indicated by medium levels

of the chemical 2-Furanmethanol Acetate Reduce amount of pyridine in coffee to also reduce burnt/smoky aroma and

taste Darker roasts with Acetaldehyde can either be very popular or very

unpopular which means companies need to create coffee matching preference of demographic targeted

2, 5-Dimethylfuran which is tied to caramelizing of sugars is very popular and leads to satisfaction

Simply give students what they want through coffee shops having unique blends