Lactones in wine

Significance of the topic

Chiral lactones are key aroma contributors in wine, imparting creamy, coconut and fruity notes. The enantiomeric composition influences sensory perception and can serve as a marker of fermentation pathways, grape varietal authenticity and aging processes.

Objectives and overview of the study

This application note describes a rapid gas chromatographic method for the simultaneous separation and quantification of eight lactone enantiomers in wine. The goal is to achieve baseline resolution of gamma and delta decalactone and dodecalactone enantiomers in under 60 minutes using a CP-Chirasil-DEX CB column.

Utilized Instrumentation

• GC-capillary system equipped with a PTV splitless injector
• Agilent CP-Chirasil-DEX CB fused silica column (0.25 mm × 25 m, df = 0.20 μm)
• Carrier gas: helium at 1.8 mL/min
• Oven program: 40 °C (1 min), ramp 20 °C/min to 100 °C (1 min), then to 190 °C (5 min)
• Injector temperature program: 30 °C (0.2 min), ramp 12 °C/s to 80 °C (1 min), ramp 12 °C/s to 220 °C (5 min)
• Detection by GC/MS in selected ion monitoring (SIM) mode

Main results and discussion

The method achieved clear separation of gamma decalactone R/S, delta decalactone R/S, gamma dodecalactone R/S and delta dodecalactone R/S enantiomers within 60 minutes. Chromatograms showed symmetric peaks with baseline resolution, enabling accurate quantification at 100 μg/mL concentration. The SIM detection provided high sensitivity and selectivity, minimizing matrix interferences.

Benefits and practical applications

• Fast and reliable enantiomeric profiling of lactones in wine for sensory and quality control.
• Chiral differentiation aids in authenticity assessment and monitoring of fermentation and aging impacts.
• Method is adaptable for routine analysis in research, quality assurance and regulatory laboratories.

Future trends and potential applications

Advances may include coupling with high-resolution mass spectrometry for trace-level analysis, method miniaturization for high-throughput screening, and integration of enantiomeric data into digital sensory models. Expanding the approach to other beverages and exploring enantiomer ratios as markers of terroir and microbial activity are promising directions.

Conclusion

The presented chiral GC/MS approach on a CP-Chirasil-DEX CB column provides a robust, under-60-minute separation of eight key lactone enantiomers in wine. It offers a valuable tool for flavor profiling, authenticity verification and quality control in the wine industry.

Reference

Agilent Technologies, Inc. Application Note A02340, October 2011