A Quest to Better Differentiate the Aromas of Beer and Wine

We’ve brought you aroma chemistry before, helpfully pointing out that you don’t need to be a connoisseur to know that the aromas associated with wine exist across a vast spectrum. But it may be less obvious that there are significant overlaps between the scents of beer and wine—and that’s causing a headache for manufacturers of non-alcoholic versions of these popular beverages, who need to hit the right flavor and aroma profiles mimic the real thing. In 2022, combined production for traditional beer and wine hit 215 billion liters.^1,2 Non-alcoholic versions may be a way behind—but it’s a booming market, with 10% growth predicted in the next decade.³ This aroma confusion seems counterintuitive: you might think that beer typically smells of malt and hops, whereas wine gives off fruity grape notes. Great, case closed, easy peasy, right? Oh, come on...this is chemistry we're talking about here!

A major proportion of the odorants in both beverage are formed during fermentation, and many research groups have tried before to unpick the nuances of their flavor profiles. Previous work agrees that all wines share a common basic aromatic structure formed by ethanol and 27 different aroma compounds, mostly byproducts of fermentation.⁴ To help unpick this further, a team in Germany set out to systematically investigate the aroma differences between beer and wine.⁵ To begin, they conducted a very sober literature survey—returning almost 15,000 concentration values from more than 1,000 beer and wine samples—identifying 40 odorants that were common to both beverages. Based on mean concentrations and a comparison with threshold data, a set of key odorants was selected to build aroma base models for each drink. These odorants, 29 from beer and 32 from wine, were chosen to reflect the basic olfactory differences.

In blind tests, an expert panel of nine trained assessors was able to repeatedly assign the aroma base models to beer or wine, respectively— confirming that the base models reflected the basic olfactory difference between the two. The odorants were classified into seven groups according to the predominant character: buttery, fruity, malty, honey, sweaty, sulfurous, or miscellaneous. Initial findings revealed that the biggest difference between the beer and wine aroma models was in the buttery odorants, followed by fruity, malty, and miscellaneous groups; there was no substantial difference in honey, sweaty, or sulfurous notes. But it was the subsequent orthonasal concentration leveling tests that finally revealed the crucial role of 11 fruity compounds—predominantly esters. When these compounds in the beer model were adjusted to the respective concentration levels in the wine aroma base model, the sensory panel no longer described the sample as beery, but more like a wine. This suggests that the higher ester levels in wine are the crucial parameter for aroma differences to beer.

The authors do note some additional real-world factors that contribute to the different perceptions of beer and wine aromas—for example, drinking temperature and the role of foam or carbonation. Another consideration is that flavor profiles in wine age over time, as demonstrated in a 2021 piece characterizing odorants in a decade-old Riesling.⁶ Although usually consumed within the first few years after bottling, this variety develops more pronounced maple, honey, and caramel notes when aged.

Gas chromatography−olfactometry has previously been responsible for identifying completely novel odorants in wine and beer,^7-9 and it is fairly well established in the field. Martin Steinhaus, a corresponding author of this new study, has penned a chapter on the practical application of this technique in food analysis¹⁰ and also been involved in developing a tool that isolates volatile fractions from foods and beverages to allow analysis of odor-active compounds.¹¹ This automated solvent-assisted flavor evaporation (aSAFE) was employed in the current work to obtain volatile isolates from four commercial beverages.⁵ The key finding—that odorant composition dominates the matrix composition in beer and wine aromas—might be used to develop innovative low-alcohol beverages that meet changing consumer preferences.

References

1. Barth-Haas Group. Beer Production Worldwide from 1998 to 2022 (in Billion Hectoliters). Statista: Hamburg, Germany, 2023.
2. World Wine Production Outlook–OIV First Estimates. International Organisation of Vine and Wine: Dijon, France, 2023.
3. Kucherenko, V. and Uspalenko, O. Relevance of the production of non-alcoholic wines. BIO Web Conf. 2023, 68, 03017.
4. Ferreira, V. 1 - Volatile aroma compounds and wine sensory attributes. In: Managing Wine Quality; Viticulture and Wine Quality. Woodhead Publishing Series in Food Science, Technology and Nutrition 2010, 3–28.
5. Wang, X. et al. Molecular Insights into the Aroma Difference between Beer and Wine: A Meta-Analysis-Based Sensory Study Using Concentration Leveling Tests. J. Agric. Food Chem. 2024, 72, 40, 22250–22257.
6. Dein, M. et al. Characterization of Odorants in a 10-Year-Old Riesling Wine. J. Agric. Food Chem. 2021, 69, 38, 11372–11381.
7. Culleré, L. et al. Gas Chromatography−Olfactometry and Chemical Quantitative Study of the Aroma of Six Premium Quality Spanish Aged Red Wines. J. Agric. Food Chem. 2004, 52, 6, 1653–1660.
8. Frank, S. et al. Reconstitution of the Flavor Signature of Dornfelder Red Wine on the Basis of the Natural Concentrations of Its Key Aroma and Taste Compounds. J. Agric. Food Chem. 2011, 59, 16, 8866–8874.
9. Féchir, M. et al. Molecular Insights into the Contribution of Specialty Barley Malts to the Aroma of Bottom-Fermented Lager Beers. J. Agric. Food Chem. 2021, 69, 29, 8190–8199.
10. Steinhaus, M. Chapter 9: Gas Chromatography–Olfactometry: Principles, Practical Aspects and Applications in Food Analysis. In: Advanced Gas Chromatography in Food Analysis 2019, 337–399.
11. Schlumpberger, P. et al. Development and evaluation of an automated solvent-assisted flavour evaporation (aSAFE). Eur. Food Res. Tech. 2022, 248, 2591–2602.