Caffeine Transport in Single Cup Coffee Packets
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Transcript of Caffeine Transport in Single Cup Coffee Packets
Caffeine Transport in Single CupCoffee Packets
Eric AndersonAlana Warner-Tuhy
Introduction
• Reason for Study• Experimental Parameters• Results• Conclusions• References
Justification for Study
• Warning on the back of coffee packet• How much does brewing conditions affect the
final caffeine concentration?
Experimental Parameters• Three different brewing methods– No interference– Dunk bag in water, as per directions– Continuously stir
• Other than convective conditions, all other parameters were constant
Purification and Extraction
Method 1 Results
0 1 2 3 4 5 6 7 8 9 100
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
Color and Caffeine Comparison
Color Caffeine
Time (min)
Nom
alize
d Co
ncen
trati
on
Color Comparison
0 10 20 30 40 50 600.000
0.200
0.400
0.600
0.800
1.000
1.200
1.400
Color Dependence on Time
Still Dunked for 15 sec at 1 min Well Mixed
Time (min)
Abso
rban
ce
Caffeine Conc. Comparison
0 10 20 30 40 50 60 700
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
Caffeine Concentration
StillDunkedStirred
Time (min)
Caffe
ine
Conc
entr
ation
(mg/
mL)
Final Caffeine ComparisonMethod Time (min) Final Concentration (mg/ml)
1 5 0.12
2 5 0.14
3 5 0.13
1 10 0.22
2 10 0.14
3 10 0.52
1 60 0.39
2 60 0.15
3 60 0.92
Results
5 Minutes– Any method will work
10 Minutes– Double the caffeine by leaving coffee undisturbed– 4 times the caffeine by continuously stirring coffee
Conclusions
• The convective component greatly affects the final caffeine concentration
• Color is not an adequate indicator of caffeine concentration
References
• Spiro, M., Lam, P., Food Chemistry, 1995 , vol. 54, p393-396.