Elemental Profiling of Whiskey using the Agilent 5100/5110 ICP-OES and MPP Chemometrics Software

Importance of the topic

Global whiskey production represents a multibillion-dollar industry where product value hinges on type, origin, age, and authenticity. Elemental profiling offers a powerful tool to verify geographic and processing signatures, protect brand integrity, and guard against fraudulent practices.

Objectives and overview of the study

This study evaluated the Agilent 5100 Synchronous Vertical Dual View ICP-OES for multi-element analysis of 69 commercial whiskeys spanning Bourbon, Irish, Japanese, Rye, Scotch, and Tennessee styles. Agilent’s Mass Profiler Professional (MPP) software was used to explore data patterns and assess the capability to discriminate samples by type, age, and region.

Methodology and instrumentation

The analytical workflow included:

• Instrumentation: Agilent 5100 ICP-OES with Dichroic Spectral Combiner, vertical torch, solid-state RF generator; axial view selected for trace-level elements.
• Sample preparation: 20× dilution in 1% HNO₃/0.5% HCl to 2% ethanol matrix; triplicate measurements.
• Calibration: Six-point, matrix-matched standards (0–1000 µg/L) for 21 elements, with correlation coefficients ≥0.999.
• Quality control: Method detection limits determined from blanks; spike recoveries within ±10%; calibration checks every 10 samples.

Main results and discussion

Key findings:

• Excellent calibration linearity and low MDLs allowed reliable quantification of elements such as Cu, Mg, Zn.
• Elemental concentrations varied by whiskey type; Cu differences reflected distillation equipment (copper vs stainless steel).
• Box-whisker plots in MPP highlighted distinct element distributions by age category, whiskey style, and Scotch regions.
• PCA using significant elements (Ba, Na, Mg, Sr, Rb, Al, K, Mn, etc.) explained over 57% of variance, achieving clear separation trends among whiskey groups.

Benefits and practical applications

Elemental profiling via ICP-OES and MPP enables:

• Rapid authentication and differentiation of whiskey products based on provenance and processing history.
• Quality control of raw materials (water, grains) and processing equipment impacts.
• Protection against counterfeiting and support for regulatory compliance.

Future trends and applications

Emerging directions include:

• Extension of element panels to enhance discriminatory power and traceability.
• Integration with complementary spectroscopic or mass spectrometric approaches.
• Advanced chemometric and machine learning models for automated classification.
• Collaborative creation of comprehensive elemental fingerprint databases across the industry.

Conclusion

The Agilent 5100/5110 ICP-OES, combined with Mass Profiler Professional software, offers a robust, sensitive, and reproducible platform for whiskey elemental profiling. The approach successfully distinguished multiple whiskey types and demonstrated strong potential for product authentication and quality assurance.

References

• 1. World whiskies consumption and production trends.
• 2. Heymann H. et al. Advances in Wine Research; ACS, 2015, pp. 109–122.
• 3. Hopfer H. et al. Elemental Profiles of Whisk(e)y Allow Differentiation by Type and Region; Beverages, 2017, 3, 8.
• 4. Hopfer H. et al. Combined Impact of Vineyard Origin and Processing on Red Wine Elemental Profile; Food Chem., 2015, 172, 486–496.
• 5. Nelson J. et al. Elemental Profiling of Malbec Wines Using MP-AES; Am. J. Enol. Vitic., 2015, 66, 373–378.
• 6. Harrison B. et al. Impact of Copper in Malt Whisky Pot Stills on Spirit Composition; J. Ind. Microbiol. Biotechnol., 2011, 117, 106–112.
• 7. Ibanez J. G. et al. Metals in Alcoholic Beverages: Sources, Effects, Analysis; J. Food Compos. Anal., 2008, 21, 672–683.