Abstracts
Please find below the abstracts from the current issue.
The complete Reader Service archive can be found on http://www.genios.de
Lignin as a bio-based alternative for beer stabilisation
Lignin als biobasierter Ansatz zur Bierstabilisierung
Brightness is a key quality attribute of filtered beers. To ensure this as well as its stability over the best-before period, there is growing interest in alternatives to traditional stabilisation agents such as silica gel – one such alternative might be enzymatically interlinked lignin as a bio-based stabilisation agent. Due to its protein-binding properties and low water solubility, lignin shows enormous potential for beverage stabilisation. A current research project is investigating the suitability of enzymatically interlinked lignin as a sustainable alternative to classical beer stabilisation.
Descriptors: Stabilising agent, interlinked lignin, brightness, beer stabilisation
By Korbmacher, A., Kerpes, R., Becker, T.
Source: BRAUWELT 1 2026 (166), 14-16
More than a mere contributor to bitter substances
Mehr als nur Bitterstofflieferant
Hops are not just an indispensable raw material for beer brewing, they also have major potential as a medicinal plant. The rising number of medical research projects and innovations relating to hop products open up new options for the development of hop-based beverages with an additional functional benefit, as well as dietary supplements.
Descriptors: Hops, pharmacological potential, bitter substances, hop fractions
By Schönberger, C.
Source: BRAUWELT 2 2026 (166), 48-51
Phenolic beer aroma compounds – off-flavour or aroma-defining?
Phenolic aroma compounds can significantly impact the aroma profile of beverages. Depending on beer style and consumer expectations, they are regarded both as valuable aroma compounds as well as off-flavours. The latter case is referred to as phenolic off-flavour (POF).
Descriptors: phenolic off-flavour, contamination, microorganisms, analytical method
By Kunz, O., Lehnhardt, F., Gastl, M.
Source: BRAUWELT International 1 2026 (44), 18-21
Thiol groups are determinant for overcoming acetic acid and pH stress in wine and beer fermentation-derived Saccharomyces cerevisiae strains
Acetic acid (AA), a natural by-product of ethanol fermentation in yeast cells, is widely present in lignocellulosic hydrolysate as a fermentation inhibitor. Thus, gaining insight into the molecular mechanisms of AA tolerance in yeast is particularly relevant for industrial applications. This study investigates the response to AA stress in two Saccharomyces cerevisiae strains (ATCC 9804 and ATCC 13007) during different metabolic states (fermentation, respiro-fermentation, and respiration) and external pH levels (3․0 and 4.5). The results show that AA reduces the viability of both strains in a dosage-dependent manner. Moreover, ATCC 13007 is more sensitive to AA stress compared to ATCC 9804. Respiratory metabolism and higher pH correlate with better resistance to AA stress. Catalase activity was observed to increase by 1.5–6-fold under AA stress conditions, in accordance with changes in yeast thiol group content and growth. The influence of AA stress is reactive oxygen species-dependent, and redox balance regulation was found to increase the robustness of S. cerevisiae ATCC 13007 to AA by 2-fold. The study reveals valuable insights into yeast adaptation to stress conditions, contributing to the development of robust yeast strain construction for high-yield biomass and chemicals production.
Descriptors: acetic acid, yeast, acid stress, redox balance, metabolism, carbon-source, fermentation, respiration
By Shirvanyan , A., Primavera, A., Guaragnella, N., Ledesma-Amaro, R., Trchounian, K.
Source: FEMS Yeast Research 2026 (26), https://doi.org/10.1093/femsyr/foag004
Examining the Impact of Different Malted Rice Cultivars on the Flavor of Non- and Low-Alcoholic Beers
Traditionally, malted barley has served as the primary starch source for brewing, with other grains such as rice serving as adjuncts. However, barley’s susceptibility to climate trend-induced yield decrease raises concerns for the brewing industry’s future supply. In contrast, rice, known for its climate resilience and gluten-free characteristic, emerges as a promising alternative with good malting qualities. To further explore malted rice’s brewing potential, ten malted rice and one malted pale two-row barley were fermented with Saccharomycodes ludwigii to produce non-alcoholic beer (NAB) and low-alcoholic beers (LAB) (NABLAB, 0.26–0.84% alcohol by volume). The beers produced were measured for physicochemical parameters, volatiles, and sensorial attributes. Physicochemical parameters included alcohol content, density, and color. Volatiles were analyzed using headspace solid phase microextraction gas chromatography mass spectrometry (HS-SPME-GC-MS). Sensorial attributes were quantified using descriptive analysis with a trained panel. Results showed that most malted rice self-saccharified and produced worts with higher fermentability using S. ludwigii than malted barley. Malted non-aromatic non-pigmented rice LAB were sensorially similar to malted barley NAB. Malted aromatic rice and malted pigmented rice led to unique flavor profiles, signaling the potential of rice as a novel valuable ingredient in brewing. This study sheds light on rice’s suitability for brewing and underscores the potential of malted rice to diversify beer offerings while addressing long-term sustainability concerns regarding crop yield in the brewing industry.
Descriptors: LAB, NAB, non-alcoholic beer, rice, rice beer, rice malt
By Guimaraes, B. P., Lafontaine, S.
Source: Journal of the ASBC 1 2026 (84), 23-33, https://doi.org/10.1080/03610470.2025.2566485
Hop-Derived Catechins Increase the Winter-Type Gushing Potential of Beer
Winter-type gushing refers to the spontaneous overflow of beer upon opening, due to rapid carbon dioxide release. While previous research has focused primarily on the roles of proteins and proteases in gushing, the impact of hops has not been studied extensively. In this study, the influence of malt and hops on winter-type gushing was investigated, with particular attention on the chemical components and mechanisms involved. Beers brewed with higher hopping rates exhibited significantly greater overfoaming, with malt playing an important role in inducing gushing. Fractionation of hop extract revealed that catechins are candidate compounds for promoting gushing. Chemical analyses demonstrated that catechins and procyanidins derived from hops increased the amount of overfoaming beer. Comparative analyses of polyphenols from malt and hops revealed that hop-derived catechins showed a higher gushing potential. Observations of chemical changes during storage suggest that the formation of oxidatively coupled multi-bridge oligomeric structures of catechin may contribute to gushing activity. The findings provide insights into the importance of malt- and hop-derived polyphenols in winter-type gushing and offer new insights into the underlying mechanisms.
Descriptors: Catechins, hops, multi-bridge oligomeric structures, overfoaming, polyphenols, winter-type gushing
By Kato, H., Wake, H., Kato, M.
Source: Journal of the ASBC 1 2026 (84), 34-40, https://doi.org/10.1080/03610470.2025.2581935
Explorative Study on the Interactions Between Specialty Malts and Lager Yeast Strains: Impact on Beer Aroma and Volatile Composition
The aroma of beer results from complex interactions between raw materials and microbial metabolism during brewing and fermentation processes. While the contributions of specialty malts and yeast to the beer aroma are well documented, their interplay – particularly with lager yeast strains – remains underexplored. Thus, this study investigates how four commercial Saccharomyces pastorianus strains impact the aroma of beers brewed with 100% Pilsner, 20% caramel, or 2% roasted barley malt. Pilot scale wort production and lab scale fermentation was conducted under standardized conditions. The aroma of the beers was assessed using a trained sensory panel and applying check-all-that-apply (CATA), complemented by headspace gas chromatography-mass spectrometry (HS-GC-MS) to determine volatile composition. Results revealed that both malt type and yeast strain significantly influenced beer aroma. Roasted malt exerted the most pronounced effect, but yeast strain-specific metabolic activities also distinctly modulated aroma outcomes, especially for attributes such as coffee and caramel. Analysis of volatiles confirmed strain-dependent biotransformation and selective retention of malt-derived precursors. Multiple factor analysis showed that in some cases, yeast strain had an equal or greater impact on aroma than malt type. This study challenges the view of lager yeasts as metabolically neutral and underscores the importance of strain selection for aroma optimization in lager-style beers.
Descriptors: Beer aroma, beer sensory analysis, lager yeast fermentation, Saccharomyces pastorianus, specialty barley malt, volatile composition
By Féchir, M., Janssens, P., Dorignac, E., Montandon, G.
Source: Journal of the ASBC 1 2026 (84), 50-64, https://doi.org/10.1080/03610470.2025.2583823
Interactions Between Fermentation Temperature and Yeast Strain: Impacts on Polyfunctional Thiol Release and Beer Aroma
The biotransformation and release of polyfunctional thiols (PFTs), including 3-sulfanylhexan-1-ol (3SH), 4-methyl-4-sulfanylpentan-2-one (4MSP), and 3-sulfanyl-4-methylpentan-1-ol (3S4MP), contribute to tropical fruit aromas in beer. This study examines the effect of fermentation temperature (15–30 °C) on PFT production across five commercial yeast strains. Pilot-scale beers were brewed with Cascade hops and analyzed for 29 aroma compounds. A strong temperature-dependent increase in 3SH (33–72%) was observed, with the lager yeast strain yielding the highest levels at the high-temperature condition (30 °C). However, sensory analysis indicated that elevated thiol concentrations alone did not enhance tropical aroma. Instead, increased levels of β-ionone, β-damascenone, acetate esters, and terpenoids at higher fermentation temperatures correlated with a more pronounced tropical character, particularly with the ale yeasts. These results highlight the intricate relationships between thiol levels and concurrent volatile compounds, emphasizing that elevated thiol presence alone does not directly translate to heightened tropical aromatic expression in beer.
Descriptors: Biotransformation, hops, polyfunctional thiols, yeast
By Samia, R. S., Chenot, C., Shayevitz, A., Fischborn, T., Shellhammer, T. H.
Source: Journal of the ASBC 1 2026 (84), 65-76, https://doi.org/10.1080/03610470.2025.2593042
Binding of Staling Aldehydes to the Beer Matrix: Insights into the Equilibria Through Shelf-Life Which Drive Beer Flavor Instability
The binding and subsequent release of aldehydes from beers through aging is of central importance to beer flavor change through shelf-life. Here we report fundamental studies, targeted at improving understanding of the nature of aldehyde binding to, and release from, the beer matrix. Three commercial brands of lager beer, brewed using different adjunct grist bills, were selected for the study. Each was freeze-dried and reconstituted (30% w/w, freeze dried extract/ultra-pure water) to form a concentrated solution of “beer matrix.” With this solution, the affinity and type of interactions of the matrix toward selected aldehydes were investigated. In a series of “challenge” experiments, staling aldehydes were spiked into the concentrated beer matrices and headspace solid-phase microextraction gas chromatography–mass spectrometry (HS-SPME-GC-MS) was used to determine percentage bound and percentage displacement of aldehydes measured in each case. A key finding was that each matrix displayed unique patterns of binding behavior toward the staling aldehydes. Furthermore, competitive binding was clearly observed whereby 3-methylbutanal generally showed the greatest binding on addition (and this was not impacted by the concentrations of other aldehydes present) as well as the ability to displace other aldehydes from the matrix. The full nature and range of the binding sites from which the aldehydes are being displaced remains unknown and further research is needed to better understand the complex equilibria involved in the multiple forms of binding which are envisaged to take place between aldehydes and the beer matrix.
Descriptors: Beer aging, beer flavor stability, beer freshness, bound aldehydes, staling aldehydes, Strecker aldehydes
By Maia, C., Cook, D.
Source: Journal of the ASBC 1 2026 (84), 96-107, https://doi.org/10.1080/03610470.2025.2585548
Incorporating crop rotation and malted faba beans to enhance beer sustainability
Why was the work done: The brewing industry faces growing challenges from stricter regulations and from climate change, driving the need for sustainable innovation. One approach is the use of legumes as brewing adjuncts, given their low carbon footprint and ability to fix atmospheric nitrogen in soil. Incorporating diverse crops, such as barley, wheat, oats, and faba bean, promotes regenerative agriculture but also broadens raw material use in brewing. With the aim of promoting regenerative agriculture and sustainability in brewing, this study explores a ‘crop rotation’ beer made from barley, wheat, oats, and faba bean.
How was the work done: The use of malt bills including barley, wheat, oats, and faba bean would support crop rotation and diversify raw materials. Faba bean was incorporated in both a raw and malted form. Brewing was performed at both laboratory and pilot scale, and the physicochemical and sensory properties of the beers were evaluated in comparison to barley malt beers.
What are the main findings: The results show that crop rotation worts made with malted faba beans (Sprau®) were superior to raw faba beans with improved maltose levels, greater free amino nitrogen, and more protein, alongside lower polyphenol concentration. Further, pilot scale crop rotation beers brewed with Sprau® and its starch fraction achieved a more balanced flavour profile and higher ratings for taste, aroma, and overall quality, compared to those brewed with raw faba beans. The quality scores of the beers containing Sprau® were considered 'good' (>6) and on par with those observed with commercial malted barley beer.
Why is the work important: A ‘crop rotation’ beer, utilising malt made from four different crops, can be produced with similar physicochemical and sensory properties to beer from malted barley. Incorporating legumes in the malt bill supports sustainable farming practices, enhances biodiversity, and reduces reliance on cereal grains such as barley. Compared to raw faba beans, malted faba beans (Sprau®) exhibited superior physicochemical, functional, and sensorial properties, making them more suitable for brewing application. Therefore, incorporating malted legumes can yield beers with a balanced flavour profile and this offers brewers new alternatives for improving the sustainability of their products.
Descriptors: malt, cereal, legume, faba bean, biodiversity, sustainability, crop rotation
By Deoghare, N., Koljonen, R., Rettberg, N., Wilhelmson, A., Krogerus, K.
Source: Journal of the Institute of Brewing 4 2025 (131), 211-227, https://doi.org/10.58430/jib.v131i4.85
Hop creep variability unveiled: a comparative analysis of hop variety, quantity, origin, and product type
Why was the work done: Hop creep remains a challenge for breweries producing dry hopped beers, as it leads to secondary fermentation that affects both beer quality and safety. Therefore, it is valuable to analyse hop creep across hop product types, growing regions, varieties, and concentrations to establish baseline metrics that reduce batch-to-batch uncertainty for brewers.
How was the work done: This study investigated the role of hop product types, growing regions, varieties, and extent of hop creep in laboratory fermentations. Over 450 fermentations were performed, spanning five hop product formats (T90, Cryo, whole leaf, Noble, and enriched polyphenol aroma pellets/EPAP), six growing regions, and 19 hop varieties. Hops were added at 1 g or 2 g per 100 mL (1 or 2 kg/hL) of beer, reflecting industry usage. Samples were analysed in R with multi-way ANOVA and Tukey post-hoc analysis.
What are the main findings: Significant (p < 0.05) differences were observed between hop varieties, origins, and product types, highlighting their role in hop creep. However, no significant difference was found with the amount of hops added. Widely used hop varieties, product types, and growing regions showed similar levels of hop creep.
Why is the work important: While the phenomenon of hop creep requires further investigation, these results provide insight to anticipate hop creep by hop variety, product type, and origin. This will help improve the consistency, beer quality, and safety of dry-hopped styles.
Descriptors: beer, hops, Humulus lupulus, hop creep, fermentation, dry hopping, hop variety
By Young, J., Fox, G.
Source: Journal of the Institute of Brewing 4 2025 (131), 228-237, https://doi.org/10.58430/jib.v131i4.84
Evaluation of perspective drought-tolerant genotypes of hops (Humulus lupulus L.)
Six hop genotypes with high drought tolerance were developed and submitted to the registration trials of the Ministry of Agriculture of the Czech Republic. These genotypes were planted in semi-operational plots at a dry, non-irrigated site in Nesuchyně and at an irrigated control site near the Ohře River in Rybňany. Two genotypes, 5165 and 5304, represent bitter hops with alpha-acid levels above 10% w/w. Three genotypes, 5432, 5461 and 5465, are aroma hops with alpha-acid contents ranging from 6.05% (5465) to 6.95% (5461). Genotype 5559 is a fine aroma type with subtle flavour-hop notes combining attributes typical of Saaz and Kazbek. For all genotypes, the content and composition of hop resins and essential oils, as well as the intensity and character of cone aroma, were evaluated at both sites from 2023 to 2025. In 2025, two genotypes were registered as new Czech hop varieties. Genotype 5165 was registered as Uran, with an alpha-acid content of 11.56–12.61% w/w, beta-acid content of 4.78–5.08% w/w, and essential-oil levels of 1.77–2.19% w/w. Uran exhibits a high aroma intensity dominated by spicy (black pepper, lovage, garlic, onion) and woody (conifer) notes. Genotype 5559 was registered as Art, with an alpha-acid content of 5.42–6.46% w/w, beta-acid content of 5.22–5.82% w/w, and essential-oil levels of 1.02–1.43% w/w. Art combines a hop character reminiscent of Saaz with citrus notes (lemon, orange peel, zesty lime) and fruity tones (sweet tropical fruit such as mango and papaya) inherited from its maternal variety Kazbek.
Descriptors: hops, Humulus lupulus L., varieties, drought tolerance, hop resins, hop essential oils, aroma
By Nesvadba, V., Klas, M., Charvatová, J., Trnková, S., Klasová, M., Fritschová, G., Olšovská, J.
Source: Kvasny prumysl 6 2025 (71), 1111-1121, https://doi.org/10.18832/kp2025.71.1111
Device for non-destructive determination of internal pressure in beer cans based on acoustic resonance frequency measurement
Microbiological contamination of beer often leads to the formation of carbon dioxide and consequently to an increase in internal pressure in sealed containers. Excessive pressure poses safety risks and may result in the destruction of the package. We developed and characterized a non-destructive device that determines internal pressure in beer cans by measuring their acoustic resonant frequencies. The method is based on exciting the can with a mechanical impulse and recording the resulting vibrational response with a microphone. The dominant resonant frequencies shift to higher values as internal pressure increases. Experiments performed on cans with defined CO₂ concentrations and temperatures demonstrated a linear relationship between resonant frequency and internal pressure over a wide range. The device achieves high repeatability and resolution and allows rapid, non-destructive monitoring of pressure changes in sealed cans. This makes the technique suitable for storage studies and for detecting pressure increases associated with microbiological spoilage.
Descriptors: beer, can, microbialcontamination, acoustic resonance frequency, measurement device
By Gabriel, P., Beneš, R.
Source: Kvasny prumysl 6 2025 (71), 1122-1130, https://doi.org/10.18832/kp2025.71.1122
