Optimization of Solid Phase Micro Extraction of Aroma Compounds in Wine

Importance of the Topic

The sensory profile of fermented beverages is largely defined by volatile and semi-volatile compounds responsible for aroma and flavor. Understanding and accurately measuring these compounds supports product quality control, authenticity assessment and process optimization in the beverage industry.

Objectives and Study Overview

This application note evaluates the efficiency of three solid phase micro extraction (SPME) fiber coatings in headspace sampling of wine aroma compounds. The goal is to determine which fiber provides the broadest range and highest sensitivity for key esters, alcohols and acids that characterize wine bouquet.

Methodology and Instrumentation

Sample preparation involved adding 1 g sodium chloride to 5 mL Chardonnay wine in 20 mL headspace vials. Three SPME fibers were compared:

• 100 µm polydimethylsiloxane (PDMS)
• 65 µm divinylbenzene/PDMS (DVB/PDMS)
• 50/30 µm DVB/carboxen/PDMS (DVB/CAR/PDMS)

Extractions were performed on a FLEX autosampler with drag-and-drop parameter optimization. Key parameters: 40 °C incubation, 5 min agitation, 60 min headspace extraction. Analysis by Agilent 7890 GC/5975 MS equipped with a Restek Rxi-624 Sil MS column (30 m × 0.25 mm × 1.4 µm), helium carrier at 1.0 mL/min, oven ramp from 40 °C to 220 °C. MS scanned m/z 31–265.

Main Results and Discussion

Replicate analyses showed the nonpolar PDMS fiber favored highly volatile esters but yielded low response for less volatile acids and alcohols. The DVB/PDMS fiber improved overall recovery, particularly for mid-volatility compounds. The DVB/CAR/PDMS fiber achieved the highest responses across a broad range of analytes, including ethyl caproate, isoamyl alcohol and phenylethyl alcohol, demonstrating its superior extraction capacity for both volatile and semi-volatile aroma markers.

Benefits and Practical Applications

Headspace SPME offers solvent-free sampling, minimal matrix interference and straightforward automation. Appropriate fiber selection allows targeted profiling of aroma compounds for quality assurance, product development and sensory research in enology and brewing.

Future Trends and Opportunities

Advances in fiber chemistries and automated workflows will expand analyte coverage. Coupling SPME to high-resolution MS and non-targeted screening will enhance authenticity testing and trace compound detection. Real-time monitoring and integration with chemometric tools present further opportunities in beverage analytics.

Conclusion

The DVB/CAR/PDMS fiber outperformed PDMS and DVB/PDMS in extracting a comprehensive wine aroma profile. Optimized headspace SPME on an automated autosampler provides reproducible, high-throughput analysis for routine quality control and research.

References

1. Pawliszyn, Janusz. Handbook of Solid Phase Microextraction. Chemical Industry Press of China, 2009.
2. Cannavan, Tom. Wine-pages, 21 Aug. 2014.