Abstracts

Please find below the abstracts from the current issue.
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Increasing the Security of Supply with Winter Malting Barley
Versorgungssicherheit mit Winterbraugerste steigern

Climate change is making it increasingly difficult to secure a supply of domestic summer malting barley. The resulting fluctuations in yields and quality are presenting malting plants and breweries with new challenges.

Descriptors: Winter malting barley, supply security, beer quality
By Fünfgelder, C., Neugrodda, C., Becker, T.
Source: BRAUWELT 19 2026 (166), 680-682

 

Hydrodynamic cavitation in wort boiling
Hydrodynamische Kavitation bei der Würzekochung

Wort boiling is difficult to shorten because it performs several functions at once. The most restrictive is usually the management of dimethyl sulfide (DMS): the precursor S-methylmethionine (SMM) must be converted, and the free DMS formed must be stripped from the wort. Pilot-scale experiments show that controlled hydrodynamic cavitation (HC) can intensify SMM conversion and reach a conservative total-DMS target below vigorous boiling. This article summarises the experimental basis, the relevant process parameters and the limits that still require brewery-specific validation.

Descriptors: brew house, wort boiling, dimethyl sulfide
By Meneguzzo, F.
Source: BRAUWELT 19 2026 (166), 683-686

 

Pilsner vs. Swiss Special blonde – a sensory evaluation
Pilsner vs. Schweizer Spezial hell – ein eigenständiger Bierstil?

The diversity of beer styles reflects not only different brewing techniques, but also cultural and historical developments. Two popular beer styles that, at first glance, have a great deal in common are the classic Pilsner and the ‘Special blonde’ (Schweizer Spezial hell), which is widely available in Switzerland.

Descriptors: beer styles, sensory characteristics, sensory differentiation
By Popp, M., Bongartz, A.
Source: BRAUWELT 19 2026 (166), 688-690

 

Use of Specialty Malts in the Production of New Make Whisky
Einsatz von Spezialmalzen in der Herstellung von Whisky New Makes

The whisky market is becoming increasingly diverse, with New Make Whisky—a freshly distilled, unaged whisky distillate—gaining in importance. The goal of the project was to investigate the influence of a specialty malt blend on the aroma of New Make Whisky and to identify the aromatic compounds affected.

Descriptors: Specialty malt, whiskey, new makes, flavouring
By Neugrodda, C., Felber, L., Lauck, F., Becker, T.
Source: BRAUWELT 20 2026 (166), 719-721

 

Effect of different kilning schedules on qualitative characteristics of wheat malt

Three different kilning schedules (low temperatures; medium temperatures; and high temperatures) were applied to eight varieties of different wheat species (three durum wheat, three soft wheat, one emmer variety, and one spelt variety) to evaluate the effects of kiln temperature on the main qualitative parameters of wheat malt, the difference among varieties and their interaction. For the most significant quality parameters of malt, including diastatic power, Kolbach index, FAN, and viscosity, KSA consistently yielded more favorable outcomes than medium temperature and high temperature, whose effects on malt parameters, although significant, were not particularly relevant. PCA analysis showed in Dim1, the main source of variability is the intrinsic varietal structure, and that in Dim2, a secondary but relevant source of variation, was due to kilning schedule intensity. Furthermore, the response to thermal treatment was genotype-specific rather than species-specific, and the principal technological shift occurred between low temperature and the most intense kilning schedules (medium temperature/high temperature). To gain insight into the suitability of varieties with malt quality closer to industry requirements, a non-statistical, multi-criteria deterministic tool called High Performance Index, but consistent with PCA analysis, being highly correlated with the PC1 score, was used to provide a useful decision-making tool by attempting to translate industrial requirements from analytical parameters of interest. The highest High Performance Index values were obtained from the Federico II and Antalis varieties using the kilning schedule low temperature. In the future, the study will be aimed at evaluating the same varietal set considering higher temperature levels with the prospect of reaching the production of beer.

Descriptors: Wheat malt, Kilning schedule, Malt quality, Diastatic power, HPI tool
By Suriano, S., Moscaritolo, S., Ianzano, D., Russo, M., Troccoli, A.
Source: European Food Research and Technology 2026 (252), DOI: https://doi.org/10.1007/s00217-026-05253-y

 

Microbial community and flavor-affecting metabolite variability across commercially available lambic and gueuze beers in Flanders

Lambic and gueuze beers are Flemish artisan-style beers produced through spontaneous fermentation and maturation in wooden barrels, involving successive microbial communities of Saccharomyces and Brettanomyces yeasts, lactic acid bacteria (LAB), and acetic acid bacteria. Although these beers generate culinary enthusiasm due to their complex flavor profiles and traditional character, information on the microbial and biochemical diversity among marketed end products is limited. This study explored 15 commercially available lambic and gueuze beers from different breweries and two purchase years (2023 and 2025) to provide an overview of the viable microbial consortia still present in the bottles at the time of consumption, while examining the diversity of residual carbohydrates and flavor-affecting molecules. Most bottled commercial beers remained both microbiologically viable and biochemically diverse at the time of purchase, while inter-brand differences were consistent with the non-standardized nature of lambic beer refermentation and storage. Across the beer samples examined, the viable microbial communities were predominated by Brettanomyces and certain LAB species. The metabolite profile showed high levels of lactic acid and appreciable contributions from acetic acid and Brettanomyces-derived ethyl esters, with very low residual fermentable saccharides. One outlier among the beer brands showed markedly elevated residual saccharides (glucose and fructose), which is not a property of gueuze beers, whereas another one was characterized by a distinct metabolite signature and substantially higher organic acid concentrations, indicating a strongly acidic chemical profile. These findings contributed to a deeper understanding of artisan fermented alcoholic beverage systems and their variability across commercial products.

Descriptors: Sour beer, Bottle refermentation, Lactic acid bacteria, Acetic acid bacteria, Yeasts, Metabolomics
By Croonenberghs, A.P., Ost, B., Bongaerts, D., Pradal, I., Leroy, F., De Vuyst, L.
Source: European Food Research and Technology 2026 (252), DOI: https://doi.org/10.1007/s00217-026-05239-w

 

Strain-dependent modulation of selected Ehrlich pathway-associated genes during sequential fermentation with Metschnikowia pulcherrima and Saccharomyces cerevisiae

Sequential fermentations involving Metschnikowia pulcherrima (Mp) and Saccharomyces cerevisiae (Sc) are increasingly explored as a strategy to modulate wine composition and reduce ethanol levels; however, the underlying molecular responses remain poorly resolved. In this study, we combined fermentation performance analysis with targeted gene expression profiling to investigate how sequential Mp–Sc inoculation influences both process dynamics and transcriptional activity. Fermentations were conducted in white grape juice using pure Sc cultures and Mp + Sc sequential inoculations. Fermentation kinetics (sugar consumption, pH, ethanol formation, and acidity) were monitored, and expression of key Ehrlich pathway genes (ARO8, ARO9, ADH2, and ADH5) was quantified by RT-qPCR. Sequential fermentations displayed consistently slower sugar utilization and delayed ethanol production, resulting in up to 0.9% (v/v) lower final alcohol levels compared to pure Sc cultures, alongside reduced total acidity. Importantly, sequential inoculation led to distinct, strain-dependent modulation of Ehrlich pathway gene expression, indicating that early-stage Mp activity reshapes metabolic regulation prior to Sc dominance. Together, these results demonstrate that sequential fermentation not only alters fermentation kinetics but also induces measurable transcriptional shifts in amino acid catabolism pathways. This integrative approach provides new insight into how strain-specific microbial interactions can be leveraged to fine-tune fermentation outcomes.

Descriptors: Sequential fermentation, Non-Saccharomyces, RT-qPCR, Ehrlich pathway, Fermentation kinetics
By Muyanlı, E.B., Yılmaz, R.
Source: European Food Research and Technology 2026 (252), DOI: https://doi.org/10.1007/s00217-026-05274-7

 

Cysteine, methionine, and pantothenic acid remodel the Saccharomyces cerevisiae transcriptome and volatile sulfur compound metabolome during alcoholic fermentation

Yeast nitrogen and vitamin nutrition are fundamental levers for managing wine quality, yet the specific mechanisms linking nutrient availability to sulfur aroma formation remain poorly understood. This study explored the impact of methionine, cysteine, and pantothenic acid (vitamin B5)—nutrients with direct, pivotal roles in sulfur metabolic pathways—on the Saccharomyces cerevisiae transcriptome and VSC metabolome during fermentation. Our findings reveal that methionine and cysteine catabolic routes act as isolated compartments; the genes responsible for bridging these two pathways remain transcriptionally silent in the presence of high cysteine or methionine availability. This lack of metabolic crossover leads to highly specific VSC signatures. Methionine exerts only a limited influence on global gene expression and primarily drives the production of methylthio-compounds via the Ehrlich pathway. Cysteine triggers a starvation-like transcriptomic response and promotes a diverse range of thiols and thioesters. Pantothenic acid deficiency compromised yeast growth and fermentation efficiency, triggered extensive transcriptional changes in sulfur assimilation pathways, effectively redirecting flux toward non-Ehrlich catabolic products. Overall, this study provides a robust mechanistic basis for how sulfur amino acid and pantothenic acid levels can be targeted to modulate wine aroma profiles and prevent the development of reductive off-flavors.

Descriptors: Saccharomyces cerevisiae, volatile sulfur compound biosynthesis, methionine, cysteine, pantothenic acid deficiency, wine, alcoholic fermentation
By Jiménez-Lorenzo, R., Duncan, J. D., Nolleau, V., Farines, V., Sablayrolles, J.-M., Bloem, A., Camarasa, C.
Source: FEMS Yeast Research 2026 (26), DOI: https://doi.org/10.1093/femsyr/foag022

 

Adaptive laboratory evolution of maltose utilization in wild Irish isolates of Saccharomyces eubayanus

The first European isolates of Saccharomyces eubayanus were discovered in Ireland in 2022 and belong to the same clade as the S. eubayanus parent of the hybrid lager yeast Saccharomyces pastorianus. Here, we report the isolation of 10 additional Irish strains and we explore maltose metabolism. Maltose metabolism genes are clustered in subtelomeric MAL loci including maltase (MALS), maltose transporter (MALT), and regulator (MALR). Despite having intact MAL loci, the Irish strains do not grow on maltose. Two Irish S. eubayanus strains (UCD650 and UCD926) were passaged in medium containing maltose as the sole carbon source until they acquired the ability to metabolize maltose. The UCD650-derived lineage acquired an I243N substitution in MalR, and a 30-kb duplication of the MAL locus. The UCD926 parent has a similar MAL locus duplication and its evolved lineage acquired a W307L substitution in MalR. Expression of MALT and MALS was increased in the evolved isolates. Introducing the W307L mutation into UCD926 by CRISPR-Cas9 editing fully recapitulates the maltose utilization phenotype. The I243N variant alone has little effect on expression of maltose genes. We find that maltose utilization is influenced both by the copy number of MAL genes and by gain-of-function mutations in MalR.

Descriptors: yeast, maltose, Saccharomyces eubayanus, evolution
By Bergin, S., Scully, J., Hession, C., da Silveira, J., Osborne, M., Nolan, C., O’Neill, R., Eckhardt, H.-G., Lombardi, L., Wolfe, K. H., Butler, G.
Source: FEMS Yeast Research 2026 (26), DOI: https://doi.org/10.1093/femsyr/foag036

 

Transcriptomic responses of kveik yeasts to heat and ethanol stress

Kveik strains are a group of Saccharomyces cerevisiae strains notable for their exceptional tolerance to environmental stress. To investigate the molecular basis of this robustness, the transcriptomes of three kveik strains and a conventional ale strain were compared under non-stress and stress conditions using RNA-seq. Under non-stress conditions, kveik strains showed elevated basal expression of environmental stress response genes, suggesting that part of the stress-responsive transcriptional program is active irrespective of stress exposure. Catalase activity was elevated, providing physiological support for the transcriptomic findings related to oxidative-stress defense. Under sublethal heat stress, conventional ale yeast displayed transcriptional patterns associated with cell-cycle restraint and chromosome organization, whereas kveik strains showed enrichment of genes related to protein refolding, ribosome biogenesis, and cell-wall biosynthesis, suggesting retention of a transcriptional emphasis on growth-associated processes alongside stress-protective responses. Under ethanol stress, both groups upregulated translation-related processes; however, metabolic functions were more strongly enriched in ale yeast, while kveik strains showed patterns consistent with maintenance of translation-related functions together with increased emphasis on cell surface-associated processes. Overall, kveik stress tolerance appears to reflect elevated basal preparedness and transcriptional patterns consistent with the maintenance of biosynthetic and structural processes under stress, supporting their potential suitability for intensive industrial fermentations.

Descriptors: brewing, environmental stress, novel yeasts, Saccharomyces, stress tolerance
By Shirasaya, D., Powell, C. D.
Source: FEMS Yeast Research 2026 (26), DOI: https://doi.org/10.1093/femsyr/foag043

 

Unlocking the malting potential of new Canadian hulless barley varieties, CDC Armstrong and CDC Pristine: effects of steeping and germination times

Why was the work done: Interest in hulless barley for malting and brewing continues to grow due to advantages in sustainability, higher extract, and potentially enhanced flavour. This work evaluates two new Canadian hulless varieties, CDC Armstrong and CDC Pristine, and assesses their performance under resource efficient malting conditions. How was the work done: Both barley varieties were grown in 2024 at two locations in Western Canada. Grain composition, physical traits, and properties of isolated starch granules were analysed. Both cultivars were malted using varying steeping (11, 13, 19 hours) and germination times (72, 96 hours). Routine malt quality parameters and glycosidic nitrile concentration were measured in malt, and wort was analysed for arabinoxylan, amino acids, and fermentable sugars. What are the main findings: Both cultivars exhibited low β-glucan and high starch content. CDC Armstrong had a higher proportion of A type starch granules and lower starch gelatinisation temperatures. Under shortened steeping regimes, both cultivars hydrated efficiently. CDC Armstrong had low β-glucan and wort viscosity, while CDC Pristine showed the highest α- and β-amylase activities and fermentable sugar concentration. Both cultivars produced worts with high soluble protein, FAN, together with a favourable amino acid profile and concentration. Extract levels were > 86%, exceeding the values for 2‑row hulled barley genotypes (79–82%). Analysis identified CDC Armstrong as a low glycosidic nitrile producer. Why is the work important: CDC Armstrong and CDC Pristine represent significant advances in hulless barley breeding, offering benefits in sustainability through improved malting quality, higher extract potential, and strong performance under reduced input malting conditions. CDC Armstrong shows strong suitability for both brewing and distilling applications.

Descriptors: hulless barley, hulless malt, β-glucan, water absorption, extract, glycosidic nitrile
By Izydorczyk, M., McMillan, T., Sharma, A., Beattie, A.
Source: Journal of the Institute of Brewing 3 2026 (132), 119-137, DOI: https://doi.org/10.58430/jib.v132i3.101

 

Selective control of spoilage lactic acid bacteria during fermentation by a heat stable bacteriocin from Pediococcus acidilactici HW01

Why was the work done: Fermentation requires strict microbial Control to prevent spoilage while maintaining alcoholic fermentation and sensory quality. This study evaluated a heat stable bacteriocin from Pediococcus acidilactici HW01 as a process compatible biopreservative for selective control of beer spoilage lactic acid bacteria (LAB) during fermentation. How was the work done: The bacteriocin producing strain Pediococcus acidilactici HW01 was cultivated in unhopped wort, and antimicrobial activity against the beer spoilage bacterium Pediococcus damnosus assessed. Bacteriocin activity was evaluated after wort boiling and during fermentation. Selective inhibition of P. damnosus was examined under low and high contamination levels. Yeast growth and fermentation parameters - free amino nitrogen, reducing sugar, and specific gravity - were monitored. Sensory evaluation was performed using a sensory panel to assess overall impression and key sensory attributes. What are the main findings: Pediococcus acidilactici HW01 grew in unhopped wort and produced antimicrobial activity against P. damnosus, persisting after wort boiling and remaining active for up to 18 days. The HW01 derived bacteriocin selectively inhibited P. damnosus: viable counts were significantly reduced at high contamination levels, whereas inhibition below the detection limit was achieved at low levels. Yeast growth and fermentation parameters were not adversely affected. Bacteriocin treated samples showed significantly higher overall sensory impression scores than the control, without undesirable changes in key sensory attributes. Why is the work important: These results demonstrate that the HW01 derived bacteriocin selectively suppresses beer spoilage LAB while maintaining fermentation performance and sensory quality, highlighting bacteriocin based strategies as effective, natural, and process compatible alternatives for microbial control in industrial applications.

Descriptors: bacteriocin, fermentation, beer spoilage, lactic acid bacteria, biopreservation
By Kim, J. H., Lee, H. J.
Source: Journal of the Institute of Brewing 3 2026 (132), 153-167, DOI: https://doi.org/10.58430/jib.v132i3.102