Introduction
The challenge of garnering public interest in STEM related studies has always been an ambitious undertaking. The key to effective outreach requires engaging with people on relatable topics. Researchers from the Georgia Institute of Technology accomplished this during the Atlanta Science Festival 2025. Visitors engaged with a live demonstration of a high-field NMR spectrometer, including real-time measurement and automated analysis of 1H NMR spectra. In this instance, the medium under analysis was wine; more specifically, the quantification of 70 wine metabolites, and to discuss how chemical composition relates to wine character profiles. [1]
As most of us are well aware, wine is an alcoholic drink, and the result of grape juice fermentation. [2] Wine is produced and consumed all across the world, with viticulture considered to be one of the oldest artisan crafts in human history. Dating back approximately 8000 years and believed to have originated in modern-day Georgia before spreading throughout the Mediterranean, wine has been intrinsically linked to human society. This ancient connection is what lends itself perfectly to public engagement.
Beyond a formal classroom setting, opportunities to expose the general public to practical NMR studies are few and far between. Most individuals are unfamiliar with the technology, especially in a practical sense. However, NMR could provide an excellent opportunity to engage with the general public when combined with a familiar subject.
Automated Chemical Profiling of Wine by Solution NMR Spectroscopy
The production and sale of wine represents a multibillion-dollar industry. Different wines exhibit distinct characteristics whose origins are complex, but generally defined by the region of production. The geographical factors that affect grape profiles include, regionality, climate, soil types and terrain. Additional contributors include the fermentation and production processes, as well as grape variety. [3–5]
Chemical profiling of wine is well established when it comes to analytical chemistry techniques; including Raman spectroscopy, mass spectrometry, and solution NMR. These specific techniques play a pivotal role in quantifying the more than 70 different components. The combination of NMR and food science has revealed detailed insights into chemical composition of food products, but has also determined the molecules responsible for taste, aroma, nutritional value, shelf life, and health. [6]
1D 1H NMR is an ideal approach for wine profiling due to its non-destructive nature, sensitivity, and spectral resolution. Coupled with the use of automated profiling software; such as Bruker‘s Wine-Profiling 4.0 or Wishart lab’s MagMet-W, means that practical NMR studies become more accessible to the general public and facilitates understanding of the complex mechanisms involved.
Fourteen wines representing diverse chemical space, grape cultivar, terroir, and flavour/aroma were chosen in consultations with local wine experts. Participants were given the opportunity to interact by observation, olfactorily, discussion, choosing which wines to analyse, and identifying wine fraud.
Smell tests in chemistry laboratories allow students to consider how molecular composition links to sensory properties. [7] In the context of wine, smell tests allow participants to connect chemical constituents to specific aromas; for example, esters like ethyl acetate contribute fruity smells, while higher alcohols like isoamyl alcohol contribute banana- or whiskey-like notes. [8]
Researchers highlighted two major challenges confronted by oenologists. Firstly, wine is a chemically complex mixture with unique flavour and aroma profiles that vary widely among grape varieties. These properties are determined by individual chemical composition. Secondly, wine fraud is a significant issue, both historically and in a modern context. Incidents of harmful chemical additives present in wine has been well documented. It is therefore imperative to decipher wine properties and quality for the benefit of consumer health.
Profile Sampling
Sample transport was delicately controlled by pneumatic transfer of NMR tubes. For data acquisition, a 1D 1H NOESY pulse sequence (noesypr1d) was used as it is standard for NMR metabolomics and the recommended choice for Wishart lab’s MagMet-W. MagMet-W automatically processes the NMR data, assigns each NMR peak to one of 70 molecules commonly found in wine, and estimates the concentration of each compound in micromolar (μM). This is achieved by the use of deuterated 2,2 dimethyl-2-silapentane-5 sulfonate (DSS-d6), purchased from Cambridge Isotope Laboratories Inc., as an internal calibrant. The adjacent diagram demonstrates and labels the key metabolites within each wine sample and gives an accurate insight into the concentrations contained therein.
Discussion
Following successful demonstration of the metabolic fingerprint of each sample, researchers went on to explain the historical issues of wine adulteration. For example, the addition of anti-freeze substances (diethylene glycol), as discovered in a 1980’s Austrian scandal. Or similarly, a concurrent scandal in Italy whereby methanol was added to increase alcohol content and reduce costs. Unfortunately leading to blindness and death amongst those who consumed it. Adulteration of this kind would be easily discerned by a thorough NMR screening. Thankfully, cases such as the aforementioned scandals are relatively rare nowadays. However, NMR still plays a vital role in oenology. Modern examples of wine adulteration/contamination are more likely to involve residual pesticides, PFAS (“forever chemicals”) or hazards associated with climate change.
Despite the “entry level” nature of the experiment, a tremendous amount of insights were gleaned. As a practical demonstration of the NMR process, few faults can be discerned. The restrictive aspect of performing the experiment for a variety of age groups and a spectrum of knowledge levels, at first appears daunting; with the required understanding of some complex systems in chemistry, physics and quantum mechanics necessary to fully appreciate the process, being typically beyond comprehension for the average Layman. On the contrary, researchers established an excellent methodology for a hands-on, relatable demonstration of the NMR processes. As well as a concise explanation of the analysed data provided from NMR spectra.
Innovation and discovery within the realm of Nuclear Magnetic Resonance will always be a valuable commodity, however researchers at Georgia Institute of Technology have successfully demonstrated that public awareness and understanding is just as key. Keeping science relatable when discoveries are increasingly more complex and cerebral is a formidable undertaking. It is imperative that scientists continue to inspire individuals to engage in STEM related subjects and devise further innovative ways to promote the accessibility of science worldwide.