G005807

GC Analysis of Aldehydes (PFBOA Derivatives) in Beer on SLB^®-5ms after SPME using a 65 μm PDMS/DVB Fiber

suitable for GC, application for SPME

Properties

• technique(s): gas chromatography (GC): suitable; solid phase microextraction (SPME): suitable
• test parameters: sample preparation: derivatization procedure: Add 100 μL of PFBOA solution (6 g/L) to 10 mL of deionized water in a 20 mL glass vial and seal. (Insert the PDMS/DVB SPME fiber in the headspace of the PFBOA solution for 10 min at 50 °C.); sample/matrix: 10 mL of degassed beer, 3.5 gm sodium chloride in 20 mL vial; SPME fiber: PDMS-DVB, 23 guage, 65 μm, Auto, Pk/3 (57345-U); extraction: 60 min, headspace, 50 °C, agitation (5 min on, 30 min off); desorption process: 0.10 min, 250 °C; column: SLB-5ms, 30 m x 0.25 mm I.D., 0.50 μm (28473-U); oven: 40 °C, 7 °C/min to 250 °C (14 min); inj. temp.: 250 °C; detector: MSD, SIM; MSD interface: 275 °C; carrier gas: helium, 1.1 mL/min; injection: splitless; liner: 0.75 mm I.D. SPME liner; sample: Beer
• suitability: application for SPME
• application(s): food and beverages

Description

Analysis Note

The formation of aldehydes is a major contributor to the deterioration in flavor or "staling" of beer upon storage. Research indicates that the source of these aldehydes is the type of malt used and quality of the wort produced during the brewing process. This application illustrates the use of SPME to extract aldehydes from beer, followed by on-fiber derivatization with 0-(2,3,4,5,6- pentafluorobenzyl)hydroxylamine hydrochloride (PFBOA). The aldehydes are then analyzed by GC/MS-SIM as their corresponding PFBOA derivatives. The aldehydes exist as geometric isomers, resulting in two derivatives for each. In the case of several of the analytes, these two derivatives were resolved chromatographically.

Legal Information

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