Origins of caffeine

d¹³C (‰)

d¹⁵N (‰)

d¹⁸O_smow (‰)

Synthesis (1)

−34.55

−23.64

19.02

Cola nuts (2)

−24.97

5.01

−1.49

China black tea (3)

−28.14

0.30

3.95

Chine green tea (4)

−31.57

1.5

1.99

Guarana powder (5)

−28.41

4.77

3.28

Maté (Argentine) (6)

−27.67

−1.33

−6.40

Redbull^© (7)

−25.97

4.77

−3.35

Café du Brésil (8)

−26.07

1.39

2.96

Robusta coffee from Cameroon (9)

−25.65

3.42

0.81

Arabica coffee from Haïti (10)

−26.47

7.44

−4.26

Arabica coffee from Costa Rica (11)

−26.11

0.67

−5.42

Arabica coffee from Colombie (12)

−26.97

1.75

−3.53

Arabica coffee from Kenya (13)

−25.79

2.72

5.23

Arabica coffee from Congo (14)

−27.54

3.14

1.40

Arabica coffee from Ethiopia (15)

−28.14

1.72

0.18

Robusta coffee from Ivory Coast (16)

−27.49

2.05

−0.73