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
ra Deca
f
Starbu
cks Bl
onde
Burge
r King
Starbu
cks Am
erican
o
Dunkin
Donuts
McDon
alds
0123456789
10
3.25.4
7.6
3.6 3 3
Burnt/Smoky
MAIN RATINGS
Pane
ra Deca
f
Starbu
cks Bl
onde
Burge
r King
Starbu
cks Am
erican
o
Dunkin
Donuts
McDon
alds
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
Pane
ra Deca
f
Starbu
cks Blon
de
Burger
King
Starbu
cks Ameri
cano
Dunkin
Donuts
McDon
alds
0123456789
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
Pane
ra Deca
f
Starbu
cks Blon
de
Burger
King
Starbu
cks Ameri
cano
Dunkin
Donuts
McDon
alds
0123456789
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