PhD Project: Volatile Whiskey Congeners for Authentication and Quality

The research group have already developed advanced gas chromatographic processes for profiling volatile congeners in whiskey, which will be applied to the Irish Whiskey samples in this study. We now have scope to explore additional extraction techniques and analytical features. This will not only enhance the volatile profiles generated, but also expand our capability in olfactometry, enabling the identification of odour-active congeners. No single volatile extraction method provides a complete or unbiased profile, as each carries inherent selectivity based on compound polarity,molecular weight, vapour pressure, or boiling point. In our previous study, we compared headspace solid-phase microextraction (SPME) with SPMEArrow, two widely used methods designed to capture a broad range of congeners. However, these approaches have limitations, particularly with volatiles above 200 daltons and highly hydrophilic compounds. The new extraction equipment allows us to evaluate high-capacity sorptive extraction in both headspace and immersive modes. From our experience, this approach is especially effective for extracting lactones and terpenes present in whiskey, which are less efficiently recovered by SPME. In addition, the system has an enrichment capability that can concentrate volatiles from multiple extractions—whether from the same technique or a combination of techniques. This novel functionality provides the potential to recover trace-level compounds that have previously been difficult or impossible to detect by mass spectrometry. Research on odour-active congeners in whiskey is limited, and we are keen to investigate this area in detail. Olfactometry employs a trained in-house panel to directly assess volatile compounds as they elute from the gas chromatograph, in tandem with mass spectrometry and flame ionization detection. This enables us to assign odour descriptors to individual peaks and determine relative odour intensity through aroma extract dilution analysis (AEDA). In AEDA, a gas chromatograph’s split valve is used to dilute aroma compounds stepwise, allowing the panel to rank odorants by intensity. Congeners detected at the highest dilutions are considered the most odour-active and, therefore, the most significant contributors to sensory perception. We aim to use this data to generate aromagrams of different styles of Irish whiskey, and potentially to compare brands and production factors.

Student requirements Hold a First or Second Class Honours degree (2.1 or equivalent) in chemistry, food sciences, analytical science and related disciplines Demonstrate a strong interest in analytical chemistry, flavour chemistry, or food and beverage quality. Possess good lab practice and data handling skills Demonstrate the ability to work effectively both independently and as part of a multidisciplinary research team. Possess strong written and verbal communication skills. Meet TU Dublin English language requirements. Hold a full, clean drivers license (desirable)

Funding Agency: Teagasc Walsh Fellowship Student Stipend per annum: € 25,000 Materials & Travel Budget per annum: € 5,000 Fees covered by the funding per annum: € 6,000 Duration of Funding: 48 months Deadline to submit an application: 18th March 2026 How to Apply Applicants should complete the online application form form.jotform.com/260387398389073 by 5:00pm on Wednesday, 18th March 2026. Applications must include a curriculum vitae and a 1-2 pages statement of motivation, submitted as part of the online application. Interviews Shortlisted candidates will be invited to interview in early to mid-April 2026. Online interviews can be accommodated. Further information Informal enquiries are welcome and may be directed to: Professor Kieran Kilcawley – [email protected]