Comparison between the MVM (Multi-Volatile Method), single DHS extraction and SPME (Solid Phase Micro Extraction) for extraction of volatiles in Whisky

Significance of the topic

The comprehensive analysis of volatile compounds in whisky is vital for quality control, flavor profiling, and authentication of spirits. Accurate volatile profiling supports regulatory compliance, product consistency, and differentiation in a competitive market.

Objectives and Overview

This study evaluates three headspace extraction techniques for volatile analysis in whisky:

• Headspace Solid Phase Microextraction (HS-SPME)
• Single Dynamic Headspace (DHS) with Tenax TA sorbent
• Multi-Volatile Method (MVM) combining two DHS traps (Shincarbon X/Carbopack B+X and Tenax TA)

The goal is to compare extraction efficiency, compound coverage, and sensitivity among these approaches.

Methodology

All analyses were performed in duplicate using standardized headspace protocols:

• HS-SPME: 100 °C incubation, 5 min sampling onto DVB/CAR/PDMS fiber, thermal desorption at 250 °C, DB-WAX GC column
• Single DHS: 50 µL whisky in 10 mL vial, 80 °C incubation, 750 mL Tenax TA trap, TDU ramp 30→240 °C, CIS ramp 10→240 °C, DB-WAX column
• MVM: 100 µL whisky in 10 mL vial; first trap Shincarbon X/Carbopack B+X at 55 °C (10 mL headspace), second trap Tenax TA at 80 °C (750 mL headspace); sequential thermal desorption via TDU and CIS into DB-WAX column

Instrumentation

The following instruments and software were employed:

• Agilent 7890A gas chromatograph with triple quadrupole MS detector (MS1 scan)
• Gerstel MPS 2 dual-head autosampler (fiber and syringe positions)
• Agilent MSD ChemStation (version B.07.01.1805) and Gerstel Maestro (version 1.4.30.11/3.5)

Main Results and Discussion

Chromatographic comparisons reveal that the MVM approach provides the most extensive volatile coverage and higher sensitivity for trace components:

• Detection of low-abundance analytes such as acetaldehyde, oaklactone, 1-hexadecanol, and 5-hydroxymethylfurfural (identified via NIST library)
• Enhanced recovery of mid- to high-volatility compounds compared to HS-SPME and single DHS
• Ethanol concentrated in the first trap without masking target analytes

Benefits and Practical Applications

The MVM technique offers:

• Comprehensive volatile profiling with improved sensitivity for trace compounds
• Robustness and reproducibility suitable for routine quality assurance and research
• Applicability to flavor fingerprinting, authenticity testing, and adulteration detection in whisky and other spirits

Future Trends and Potential Applications

Potential developments include:

• Extension of dual-trap DHS to other beverages and food matrices
• Integration with two-dimensional GC or high-resolution MS for more detailed compound identification
• Automation and high-throughput workflows for industrial QA/QC labs
• Real-time headspace monitoring for process control in distilleries

Conclusion

The Multi-Volatile Method utilizing two sequential DHS traps demonstrates superior performance over conventional HS-SPME and single-trap DHS, delivering a more complete and sensitive volatile profile for whisky analysis.

References

1. AS148: The development of the MVM (Multi-Volatile Method) in the whisky matrix