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GC Analysis of Volatiles in Roasted Coffee Beans on Omegawax after SPME using a 50/30 μm DVB/Carboxen/PDMS Fiber

GC Analysis of Volatiles in Roasted Coffee Beans on Omegawax™ after SPME using a 50/30 μm DVB/Carboxen/PDMS Fiber application for SPME, suitable for GC

Materials

analytical column

Product No.
Description
Pricing

Omegawax Capillary GC Column

L × I.D. 30 m × 0.25 mm, df 0.25 μm

SPME fiber

Product No.
Description
Pricing

SPME fiber assembly Divinylbenzene/Carboxen/Polydimethylsiloxane (DVB/CAR/PDMS)

needle size 24 ga, StableFlex, for use with autosampler

mobile phase component

Product No.
Description
Pricing

Ethyl acetate

anhydrous, 99.8%

related product

Product No.
Description
Pricing

SPME Fiber Holder

for use with manual sampling

SPME Fiber Holder

for use with CTC CombiPAL and Gerstel MPS2

standard

Product No.
Description
Pricing

p-Cymene

analytical standard

Methyl acetate

analytical standard

α-Terpinene

≥95.0% (GC)

γ-Terpinene

analytical standard

2,3-Butanedione

analytical standard

Pyridine

anhydrous, 99.8%

2,5-Dimethylpyrrole

98%

3,4-Hexanedione

95%

2,3-Dihydro-5-methylfuran

97%

2,5-Dimethylfuran

99%

3-Ethylpyridine

≥98%, FG

2-Ethylpyrazine

≥98%, FG

3-Penten-2-one

≥70%

2-Methylpyrazine

≥99%

Acetoin

primarily dimer, ≥95%, FG

Ethyl alcohol, Pure

200 proof, anhydrous, ≥99.5%

2-Acetyl-1-methylpyrrole

≥98%, FG

Pyrrole-2-carboxaldehyde

98%

2-Butanone solution

certified reference material, 2000 μg/mL in methanol: water (9:1)

Linalool

analytical standard

Linalyl acetate

analytical standard

2,3-Hexanedione

analytical standard

2,3-Pentanedione

analytical standard

Pyrazine

analytical standard

Furfural

analytical standard

Hexanal

analytical standard

5-Methylfurfural

analytical standard

Furfuryl acetate

analytical reference material

Pyrrole

analytical standard

Furfuryl alcohol

analytical standard

2-Methylfuran

analytical standard

2,5-Dimethylpyrazine

analytical standard

γ-Butyrolactone

analytical standard

CONDITIONS

sample/matrix

2 g of coffee beans

SPME fiber

50/30 μm divinylbenzene/Carboxen on polydimethylsiloxane on a StableFlex fiber (57329-U)

extraction

headspace, with a pre-equilibration period of 10 min. at 60 °C, and then a fiber exposure of 40 min. at 60 °C, agitated in an alternate clockwise-anticlockwise rotation mode at 500 rpm

desorption process

260 °C for 5 min

column

Omegawax 250, 30 m x 0.25 mm I.D., 0.25 μm (24136)

oven

40 °C (5 min), 4 °C/min to 230 °C, 50 °C/min to 280 °C (2 min)

inj. temp.

260 °C

detector

MS, m/z 40-400

carrier gas

helium, 34.8 cm/sec constant

injection

splitless

scan range

m/z 40-400

sample

Roasted coffee

liner

0.75 mm I.D. SPME/Splitless (2633901)

Description

Analysis Note

Headspace-SPME followed by GC analysis was used in this application to analyze volatile compounds in roasted coffee. SPME is ideal for analyzing the headspace of solid samples like coffee beans. The Carboxen/DVB/PDMS fiber is the fiber of choice for analyzing the wide range of analytes commonly found in roast coffee beans.The relatively polar Omegawax 250 GC column provided high resolution.

Legal Information

Omegawax is a trademark of Sigma-Aldrich Co. LLC