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

Significance of the topic

• Global whiskey production is a multibillion-dollar industry with complex supply chains spanning over 20 producing countries.
• Product value and legal definitions depend on type, origin, age and purity, creating a demand for reliable analytical methods to protect brand integrity and combat fraud.
• Elemental profiling offers a robust approach to fingerprint whiskey based on geographical, raw material and production-related elemental signatures.

Objectives and study overview

• Assess the capability of the Agilent 5100 SVDV ICP-OES system to determine elemental profiles of 69 commercial whiskeys covering Bourbon, Irish, Japanese, Rye, Scotch and Tennessee styles.
• Use Agilent Mass Profiler Professional (MPP) chemometrics software to explore sample clustering by type, region and age.
• Establish method performance in terms of calibration linearity, detection limits and quality control recoveries.

Methodology and instrumentation

• Sample preparation involved 20-fold dilution of each whiskey in 1 % nitric acid and 0.5 % hydrochloric acid, yielding a 2 % ethanol matrix.
• Multi-element calibration standards (0–1000 µg/L) were matrix-matched to account for matrix effects.
• Each element was measured in triplicate; a QC blank and QC verification standard were run every ten samples to monitor accuracy.

Instrumentation

• Agilent 5100 Synchronous Vertical Dual View (SVDV) ICP-OES with Dichroic Spectral Combiner.
• Axial view mode was selected for trace element sensitivity.
• Sample introduction via glass concentric nebulizer, cyclonic spray chamber and SPS-3 autosampler.
• Operating conditions: 1.20 kW RF power, 12 L/min plasma gas, 0.70 L/min nebulizer flow, read time 20 s, three replicates.

Main results and discussion

• Calibration curves for all measured elements exhibited excellent linearity (r² > 0.999), e.g. Cu, Mg and Zn.
• Method detection limits ranged from low µg/L for transition metals to tens of µg/L for elements like Se.
• Spike recoveries for a 5 µg/L QC spike were within ±10 % of expected values, confirming method accuracy.
• Box-whisker plots generated in MPP revealed distinct element distributions by whiskey age, type and Scotch region.
• Principal Component Analysis using 13 significant elements (Al, Ba, Ca, Cu, Fe, K, Mg, Mn, Na, Rb, Si, Sr, Zn) explained 57 % of total variance across PC1 and PC2.
• PC1 separation was driven by Ba, Na, Mg, Sr and Rb, while PC2 differentiated Bourbon from Irish whiskey based on Na, Al versus K, Mg and Mn levels.

Practical benefits and applications

• Elemental fingerprinting with ICP-OES and chemometric analysis enables reliable classification of whiskey types and regional origins.
• Producers and regulators can use this approach for authenticity verification, quality control and detection of adulteration.
• Data can support brand differentiation strategies and traceability in supply chains.

Future trends and applications

• Expanding the elemental panel and combining with isotope ratio analysis may enhance discrimination power.
• Integration of alternative atomic spectroscopy techniques (e.g. ICP-MS, MP-AES) offers complementary information.
• Machine learning algorithms applied to large databases of elemental and sensory data will improve predictive accuracy.
• Collaboration with industry stakeholders will guide method refinement for regulatory acceptance.

Conclusion

• The Agilent 5100/5110 ICP-OES system, paired with Mass Profiler Professional software, demonstrates a robust platform for elemental profiling of whiskey.
• Method performance meets the requirements for sensitivity, accuracy and reproducibility.
• Distinct elemental patterns allow differentiation by type, region and production practices, supporting authentication and quality control efforts.
• Further research and expanded data sets will drive adoption in commercial and regulatory laboratories.

References

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7. Agilent Technologies, Inc. Elemental Profiling of Whiskey using the Agilent 5100/5110 ICP-OES and MPP Chemometrics Software. Publication number: 5991-7858EN, 2017.