*A Detail Chemistry of Coffee and Its Analysis DOI: http://dx.doi.org/10.5772/intechopen.91725*

**S.N. Method**

**84**

1 UV

Caffeine separated from coffee

Detection was done at 272 nm

spectroscopy

2. UV spectroscopy

using TLC and was estimated

using Method A:

method

Method B: isosbestic point method

simultaneous

 equation

For method A: absorbance

2–32 μg/ml

 Tablet containing caffeine

Determination

mixture of tablets

 of caffeine in

[9]

and paracetamol

measured at 273 nm

For method B: absorbance

measured at 259.5 nm

Two wavelengths

234 nm were selected for analysis

LOD = 0.286 LOQ = 0.863

 of 249 and

3–18 μg/ml

 Tablet containing caffeine

A new method of

[10]

determination

 of caffeine

and paracetamol

3. UV spectroscopy

4. UV

Dual wavelength

 method

spectroscopy

5. HPLC 6. HPTLC-UV

 Silica gel 60F254 as stationary

phase and ethyl (27:3) as mobile phase

> 7 HPLC

Zorbax eclipse XDB comprising C8 column as stationary phase and

water-tetrahydrofuran-acetonitrile

as mobile phase

acetate/methanol

274 nm

LOD = 40 ng/zone LOQ = 120 ng/zone UV detector at 273 nm

0.2–100 mg/l

 Caffeine, theophylline

drinks, and herbal products

 in food,

theobromine,

 and

The recoveries range from

[13]

92.00 to 96.8%

LOD = 0.07 LOQ = 0.20

UV

densitometric

 remission at

2–14 μg/zone

 Caffeine in marketed tea

granules

RP-HPLC comprising and 24% methanol as mobile phase

 C18 column

UV detector at 272 nm

1–40 ppm

 Unroasted coffee and

Unroasted coffee contained

[11]

0.89–2.10 (8 samples)

Roasted coffee contained

1.03–4.21 (11 samples) Caffeine in tea samples was

[12]

found to be 2.145%

roasted coffee

spectroscopy

using paper and TLC and was

estimated using Caffeine separated from coffee

Absorbance

 measured at 274 nm

 2–120 μg/ml

 Caffeine from tea powder

 Good separation

[8]

*Coffee - Production and Research*

spectroscopy

 **Experiment**

**Detection**

**Linearity**

**Application**

**Scientific outcome**

**Ref.no.**

**range**

 NA

Caffeine from coffee

 Good separation

[7]


**S.N. Method**

**87**

15

Electrochemical

Voltammetric

Working electrode: pencil type

graphite carbon electrode

Auxiliary electrode: platinum coil

Reference electrode: Ag/Agcl

electrode

16 LC–MS/MS

 For LC, stationary phase:

LLOQ = 5 ng/ml

5–5000 ng/ml

 Caffeine and its three

primary metabolites

plasma

 in rat

[22]

*A Detail Chemistry of Coffee and Its Analysis DOI: http://dx.doi.org/10.5772/intechopen.91725*

> RP-HPLC C18

Mobile phase: isocratic mobile

phase consisting of 0.2% formic

acid in distilled water and methanol

(80:20, v/v)

For MS: with an electrospray

Ionization mode used to generate

positive [M + H] + ions

> 17 GC-NPD

 Stationary phase:

Detection was made by using

0.05–500 μg/ml Caffeine in teas, coffees,

Caffeine in: Nescafe

[23]

coffee = 246.8 μg/ml Coffee seed = 267.5 μg/ml Red Bull = 297.9 μg/ml, while

other samples contained less

caffeine

Recovery of all samples

[24]

ranges from 94.4 to 100.1%

and eight beverages

nitrogen phosphorus

LOD = 0.02 μg/ml

LOQ = 0.05 μg/ml

 detector

capillary fused silica column

Mobile phase: carrier gas, helium

(1 ml min1

> 18 Infrared

> Fourier transform infrared

The

1659 cm1 using a baseline

established

830 cm1

LOD = 3 mg L1

 between 1900 and

measurement

 was done at

NA

Caffeine in roasted coffee

samples

spectroscopy

**Table 2.** *The various analytical methods for the* 

*determination*

 *of caffeine present in coffee.*

spectroscopy

 (FT-IR) method

)

spectrometer

 equipped

 method

LOD = 9.2 mg/L

method

 **Experiment**

**Detection**

**Linearity**

**Application**

**Scientific outcome**

**Ref.no.**

**range**

0–500 mg/L

 Caffeine levels in several

Caffeine levels in several tea

[21]

samples yield relative error of

1% in the

concentrations

tea samples

#### *A Detail Chemistry of Coffee and Its Analysis DOI: http://dx.doi.org/10.5772/intechopen.91725*


#### **Table 2.**

*The various analytical methods for the determination of caffeine present in coffee.*

**S.N. Method**

**86**

11 HPLC with

Stationary phase: RP-HPLC

DAD detector at 265 nm

LOD = 0.05 μg/ml

(Spherisorb

Mobile phase: 0.01 M phosphate

buffer of pH 4

> 12 HPLC

Stationary phase: RP-HPLC C18

Mobile phase:

(8:92%)

13 LC–MS

 For LC

LOD = 11.9 ng/ml

0.05–25.00

Caffeine, trigonelline, nicotinic acid, and sucrose

in coffee

μg/mL

LOQ = 39.6 ng/ml

stationary phase: Spherisorb

S5ODS2, 5 μm Mobile phase: formic acid/

methanol

For MS: ESI source with +ve mode

> 14

Electrochemical

Voltammetric

CH1760D

standard

Working electrode: lignin modified

glassy carbon electrode

Auxiliary electrode: platinum coil

Reference electrode: Ag/Agcl

electrochemical

 working

 method with

LOD = 8.37 107

6–100 106

Caffeine content in

10.78, 8.78, 6.35, 5.85 mg/g

[20]

caffeine in coffee

Ethiopian coffee samples

mol/L

LOQ = 2.79 106

method

acetonitrile/water

Detection at wavelength

 of 245 nm. Varies with each sample

in coffee, tea, and instant

hot cocoa mixes

Caffeine and

theobromine

Instant tea: 32.4–35.0 mg/cup

[18]

of caffeine

Tea bag: 30.2–67.4 mg/cup,

1.0–7.8 mg/cup of caffeine

Instant hot cocoa:46.7– 67.6 mg/cup of caffeine

Ground coffee: 93.0– 163.5 mg/cup of caffeine

Caffeine values ranged from

[19]

843.3 to 930.9 mg/100 g coffee in green and roasted

Arabica coffee samples

 ODS2 column)

DAD

 **Experiment**

**Detection**

**Linearity**

**Application**

**Scientific outcome**

**Ref.no.**

**range**

0.05–500 μg/ml Thermal degradation

 of

For Brazil: green coffee (g/kg

of caffeine), 12.36

roasted coffee, 16.12

For Ivory Coast: green coffee

(g/kg of caffeine),

20.83

25.55

 0.185

 0.22; roasted coffee,

 0.10;

[17]

 0.05

*Coffee - Production and Research*

caffeine in coffee of Brazil

and Ivory Coast

*Coffee - Production and Research*
