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Lager yeasts are limited to a few strains worldwide, imposing restrictions on flavour and aroma diversity and hindering our understanding of the complex evolutionary mechanisms during yeast domestication. The recent finding of diverse S. eubayanus lineages from Patagonia offers potential for generating new lager yeasts with different flavour profiles. Here, we leverage the natural genetic diversity of S. eubayanus and expand the lager yeast repertoire by including three distinct Patagonian S. eubayanus lineages. We used experimental evolution and selection on desirable traits to enhance the fermentation profiles of novel S. cerevisiae x S. eubayanus hybrids. Our analyses reveal an intricate interplay of pre-existing diversity, selection on species-specific mitochondria, de-novo mutations, and gene copy variations in sugar metabolism genes, resulting in high ethanol production and unique aroma profiles. Hybrids with S. eubayanus mitochondria exhibited greater evolutionary potential and superior fitness post-evolution, analogous to commercial lager hybrids. Using genome-wide screens of the parental subgenomes, we identified genetic changes in IRA2, IMA1, and MALX genes that influence maltose metabolism, and increase glycolytic flux and sugar consumption in the evolved hybrids. Functional validation and transcriptome analyses confirmed increased maltose-related gene expression, influencing greater maltotriose consumption in evolved hybrids. This study demonstrates the potential for generating industrially viable lager yeast hybrids from wild Patagonian strains. Our hybridization, evolution, and mitochondrial selection approach produced hybrids with high fermentation capacity and expands lager beer brewing options. Author summary: Lager beer dominates the global market, accounting for over 90% of commercial beer varieties. The main player in lager fermentation is the yeast Saccharomyces pastorianus, an interspecific hybrid between S. cerevisiae and S. eubayanus. Despite its popularity, the range of flavours and aromas found in lager beers is restricted by the low genetic diversity of available lager strains. Here, we explored if lager yeast profiles can be diversified by leveraging natural isolates of S. eubayanus from Chilean Patagonia. We generated de novo hybrids between S. cerevisiae and three distinct S. eubayanus Patagonian lineages. Through experimental evolution and selection on fermentation traits, we improved the fermentation profiles of the hybrids. We found that mutations in IRA2, IMA1, and MALX genes enhanced their maltose and maltotriose metabolism, resulting in higher ethanol production and unique aroma profiles. Our results also confirm that S. eubayanus mitochondria confer a greater evolutionary potential than S. cerevisiae mitochondria. The current study encourages the use of wild yeast strains to develop new brewing applications to expand the repertoire of de novo lager yeasts. [ABSTRACT FROM AUTHOR]

Consumer acceptability of beers is influenced by product formulation and processing conditions, which impart unique sensory profiles. This study used multivariate techniques to evaluate at‐home consumer sensory acceptability of six commercial beers considering their style, fermentation type, and chemical composition. Samples included top‐fermented beers (American India Pale Ale and Stout) and bottom‐fermented beers (Pilsner, zero‐alcohol Pilsner, Vienna Lager, and Munich Dunkel). Beer consumers (n = 50) conducted sensory hedonic, check‐all‐that‐apply (CATA) and just‐about‐right (JAR) tests. Chemometric variables included iso‐alpha‐acids, hordenine, and volatile aromatic compounds, quantified by chromatographic methods, whereas bitterness units (IBU) were determined spectrophotometrically. Lager beers had higher acceptability than top‐fermented beer (p <.05) for all attributes. Light‐colored beers and medium‐height foams had the highest liking scores for visual sensory attributes. Higher concentrations of bitter‐tasting molecules, hordenine, and acidity decreased the liking scores of top‐fermented (Ale) beers, as a sensory penalty analysis suggested. In contrast, the most favored beers (Pilsners and Munich Dunkel) contained higher fusel alcohol esters linked to fruity aromatic notes. Although a low conversion rate of fatty acids into fruity esters was noted in nonalcoholic Pilsner, its overall liking score was not statistically different from the alcoholic version. However, consumers perceived the nonalcoholic Pilsner as less bitter than its alcoholic counterpart even when IBUs were nonsignificantly different. This study emphasized the significance of understanding beer chemometrics to comprehend consumer acceptability, highlighting the crucial role of bitter molecules. Hence, hordenine, acidity, and volatile contents provided additional and valuable insights into consumer preferences. [ABSTRACT FROM AUTHOR]

Why was the work done: To investigate the impact of pasteurisation and storage in bottle on aroma compounds in pale lager beer. How was the work done: Pale lager beer was produced at an industrial scale with 100% pilsner malt and a bottom fermenting yeast. Samples were taken of unpasteurised beer from bright beer tank, after flash pasteurisation and six months after packaging in amber glass bottles. What are the main findings: Post pasteurisation, a marked increase was found in the concentration of 2,3-pentanedione (50%) and diacetyl (33%), presumably reflecting the decomposition by heat of precurser acetohydroxy acids. There was also a marginal increase in dimethyl sulphide (6%) with little or no change in other aroma compounds. Storage for six months in bottle, also resulted in an increase in the level of 2,3-pentanedione, diacetyl and dimethyl sulphide. The linear (Pearson) correlation was > 0.8 for both dimethyl sulphide and diacetyl, and 2,3-pentanedione and diacetyl. Accordingly, it was concluded that the levels in beer of dimethyl sulphide and 2,3-pentanedione are proportionally related to diacetyl. Why is the work important: This work provides an insight into the effects on flavour and aroma of lager of flash pasteurisation and subsequent storage in bottle. The inter-relationship between aroma compounds in beer suggests that such synergies may undermine the sensory perception of threshold levels and identification of specific aromas. [ABSTRACT FROM AUTHOR]

Why was the work done: Ascospores from Saccharomyces cerevisiae BRYC 501 are useful biological indicators for validating the pasteurisation of beer. Ascospores are formed by yeast in response to low nutrient conditions and are characterised by greater resistance to stressors including desiccation, freezing and, during pasteurisation, high temperatures. Accordingly, the sporulation temperature of yeast ascospores, their shelf life, heat resistance and recovery need to be investigated. How was the work done: The role of temperature in sporulation was investigated at 25, 27 and 30°C by measurement of the rate of sporulation over ten days. Shelf life of ascospores was established in deionised water at 1-5°C over 120 days by the measurement of heat resistance in McIlvaine's buffer. The recovery conditions of ascospores were determined using six agars after heat inactivation experiments in McIlvaine's buffer, alcohol free and lager beer. What are the main findings: The sporulation rate of S. cerevisiae ascospores was highest at 27°C, and lowest at 30°C. Heat resistance of ascospores formed at 30°C was low with a D60 value of <3 minutes, whereas at 25 and 27°C the D60 was 8.8 and 9.2 minutes. The shelf life of ascospores was 60 days after an initial 14 days of maturation at both 25 and 27°C. The variation of heat resistance for ascospores grown at 25°C was shown to be lower than those grown at 27°C. Use of yeast extractpeptone-glucose agar to recover heat injured cells was > 200% higher than with the control agar. Why is the work important: Sporulation should be performed at 25°C to produce the maximum number of spores for heat inactivation experiments. Spores can be maintained for 60 days, enabling several experiments to be performed. After heat inactivation experiments, ascospores should be recovered on YEPG agar for 10 days at 27°C. [ABSTRACT FROM AUTHOR]

Beer is an age-old alcoholic, recreational beverage popular worldwide. It is produced by the process of brewing which involves the enzymatic fermentation of the mixture of water, starch, and hops by yeast in a specific condition. Production of beer from cereal grains involved several steps including grain treatment, malting, mashing, lautering, filtration, fermentation, maturation, finishing, and packaging. The brewing process has a marked effect on the quality, taste, aroma, consistency and alcoholic content. Several types of beers with distinct characteristics can be produced by varying the brewing conditions and yeast flora. Apart from psychoactive affects beer can have several medicinal benefits when consumed in moderation. This review presents a detailed understanding of the several steps for enhancing the brewing process for commercial beer production with desirable quality and flavour. The review also highlights current research progress in the innovative methods and techniques adapted for the cost-effective production of beer, including key advances, potential applications and limitations. Therefore, keeping in view the demands of beer in human daily life, there is an extensive need to commercialize these processes by developing and optimizing novel strategies for cost-effective beer production. [ABSTRACT FROM AUTHOR]

Introduction. Chicory root (Cichorium intybus L.) contains valuable components such as inulin, inulides, bitter substances, pectin, and fibers and is a promising non-traditional raw material for the production of new beer varieties and reduction of their cost. Materials and methods. Dried and roasted chicory roots, lager and caramel barley malt, enzyme preparation inulinase, granulated hops of "Agnus" variety, yeast Saccharomyces cerevisiae (race RH) were used. Inulin content was determined by spectrophotometric method, amine nitrogen was measured by Pope and Stevenson method, content of reducing substances was estimated by Wilstetter-Schudl method. Standard methods accepted in brewing were used to determine other beer characteristics, sensory parameters were evaluated using profile methods. Results and discussion. The technology for light beer production was proposed, according to which light malt and dried crushed chicory roots taken in the amount of 4% of malt are used as raw materials, and at the stage of mashing the enzyme preparation inulinase with activity of 14 units/g was introduced into the mixture. For the hydrolysis of inulin at the mashing stage, an inulase pause was provided at a temperature of 55-56 ℃ for 20-30 minutes. The method allows increasing the content of reducing substances in the wort by 1.6%, the apparent and actual fermentation degree by 3.9%, the content of alcohol and carbon dioxide in the beer by 3.2 and 10%, respectively. The finished beer had increased foam resistance and higher foam height, while the introduction of chicory did not impart excessive and extraneous bitterness. The innovative technology of dark beer provides mixing of aqueous extract of roasted chicory with malt wort cooled to the temperature of 85-90 ℃. It was found that the optimal mode of the extraction process was the temperature 85-90 ℃, hydromodule 1:6, and duration 90 min. Beer with chicory content of 3% was the best in terms of physical, chemical, and sensory properties. The improved method allows to increase the content of reducing substances in wort by 1.5%, apparent and actual fermentation degree by 2.2 and 3%, respectively, to increase the content of alcohol in beer by 2.3%, and carbon dioxide by 3.2%. It was proved that partial replacement of malt by chicory allows to reduce consumption of bitter hops for light beers by 20% (from 14.8 to 12.0 g/dal) and for dark beers by 10% (from 10.3 to 9.3 g/dal). Conclusions. The addition of dried and fried chicory roots makes it possible to obtain new varieties of high-quality beer with their cost reduction. [ABSTRACT FROM AUTHOR]

The article explores the challenges faced by beer production, particularly for craft brewers, due to the potential decline in yields and quality of beer hops, a crucial ingredient. Topics discussed include the impact of climate change on hop yields and beer quality, the need for adaptation in traditional farming practices, and the potential solutions offered by biotechnology, such as engineered yeasts and genetic modification, to enhance beer flavors.

The rapid and efficient consumption of carbon and nitrogen sources by brewer's yeast is critical for the fermentation process in the brewing industry. The comparison of the growth characterizations of typical ale and lager yeast, as well as their consumption preference to carbon and nitrogen sources were investigated in this study. Results showed that the ale strain grew faster and had a more extended stationary phase than the lager strain. However, the lager strain was more tolerant to the stressful environment in the later stage of fermentation. Meanwhile, the ale and lager yeast strains possessed varying preferences for metabolizing the specific fermentable sugar or free amino acid involved in the wort medium. The lager strain had a strong capacity to synthesize the extracellular invertase required for hydrolyzing sucrose as well as a strong capability to metabolize glucose and fructose. Furthermore, the lager strain had an advantage in consuming Lys, Arg, Val, and Phe, whereas the ale strain had a higher assimilation rate in consuming Tyr. These findings provide valuable insights into selecting the appropriate brewer's yeast strain based on the wort components for the industrial fermentation process. Key points: • The lager strain is more tolerant to the stressful environment. • The lager strain has the great capability to synthesize the extracellular invertase. • The assimilation efficiency of free amino acid varies between ale and lager. [ABSTRACT FROM AUTHOR]

Beer ranks third in terms of consumption worldwide, and its technology is constantly being improved and perfected. The boom in craft brewing has led to the production of thousands of new types of beer, but most often without scientific justification of the technological decisions made. This paper discusses the approaches to the modeling of the composition of the malt mixture and the mode of lager beer production. A special cubic simplex-lattice design with two replications was used to model the mixture with three malt types: Pilsner, Caramel Pils and Caramel Munich type 2. Models for the main brewing characteristics, i.e., wort extract and color, as well as models for the biological parameters of the mash, i.e., phenolic compound content and antioxidant potential, were developed using different methods. Multi-objective optimization was carried out and a specific mixture was developed for the production of lager beer. The influence of acidulated malt, lactic acid and CaCl2 additions on the extract yield and malt mash filtration time were established through one-factor experiments. The extract and fermentable sugar yield during individual pauses in the mashing mode was studied with a view to its optimization. [ABSTRACT FROM AUTHOR]

Why was the work done: To determine whether the susceptibility of lager to microbiological spoilage is determined by composition, microbiota or both. To assess beer spoilage by a consortium of yeast and bacteria from draught beer rather than pure laboratory cultures. How was the work done: Four draught beer styles - cask ale and keg lager, ale, and stout - were sampled twice in five different public houses in four different locations. The beers were forced by static incubation at 30°C for four days. 'Challenge testing' with an inoculum of heterogeneous microorganisms from the forced samples was used to assess the spoilage of ten commercial lagers after incubation by the increase in turbidity at 660 nm. The same approach was used to evaluate the role of nutrients in beer spoilage by forcing with the addition of yeast extract or vitamins (thiamine and riboflavin). What are the main findings: The ten lagers varied in susceptibility to spoilage ranging three-fold from the least to most spoilable. Average spoilage across the beers was comparable for microorganisms from lager, keg ale and stout but ca. 50% greater with microorganisms from cask ale. The ranking of spoilage of the 10 lagers was similar for microbiota from cask ale, keg ale and stout but less so from lager. Spoilage was influenced by beer composition and was inversely related to beer pH and level of free amino nitrogen. The addition of yeast extract stimulated spoilage of the least spoilable lager but the addition of vitamins B1 and B2 had little or no effect. Spoilage was extensive at 30°C, measurable at 12°C but imperceptible at 2°C. Why is the work important: The oft-quoted statement that beer is 'robust to microbiological spoilage' is a fallacy. All ten lagers were spoilt by draught beer microorganisms, but some were more spoilable than others. It is suggested that spoilage may be reduced by lowering beer pH and curbing the availability of nutrients for microbial growth. Whilst (as would be expected) beer storage at 2°C supresses microbial growth, storage at 12°C (as practiced in UK public house cellars) allows spoilage microorganisms to grow in beer. Although the threat of microbial spoilage in the brewing process is managed by good manufacturing practice, draught beer is vulnerable and requires more focus and commitment to hygienic practices to assure quality. [ABSTRACT FROM AUTHOR]

At present, non-alcoholic (NAB) and low-alcoholic beers (LAB) exhibit major staling defects even when fresh, partly due to absence of ethanol as an antioxidant. In the present work, the aroma stability of eleven commercial NABLABs available on the Belgian market, issued from different technological processes, was assessed. NABLABs were investigated, both when fresh and after one year of storage at 20 °C in the dark. Six stale-odorant compounds were found above their perception threshold in aged NABLABs: sotolon, abhexon, methional, phenylacetaldehyde, dimethyltrisulfide and β-damascenone. Based on the chemical structure of the first four, it can be concluded that oxidation is the main issue for NABLABs aging. Yet, five of these usual staling defects of a six-month lager beer were already key-odorants in fresh NABLABs: dimethyltrisulfide, methional, and β-damascenone were above the thresholds in all samples, phenylacetaldehyde in 10 out of 11, and sotolon in 7. In conclusion, development of efficient antioxidants is needed to improve NABLABs acceptability. [ABSTRACT FROM AUTHOR]

AbstractModern breweries are focused on controlling oxidation in beer using natural antioxidants to improve shelf-life stability. The most significant quality issues in the brewing industry are flavor instability and oxidation. In this research, the effects of adding Moringa stenopetala leaf extract to lager beer at 400, 600, and 800 ppm concentrations for 30, 60, and 90 days storage at 25ºC were investigated. The total phenolic and total flavonoid content were measured by Folin-Ciocalteu and aluminum chloride method, respectively. Using the 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and the phosphomolybdate assay, the antioxidant activity of each treatment was assessed and compared. Addition of the extract in beer showed a linear increment in the total phenolic content from 46.79 up to 88.30 milligram of gallic acid equivalent per liter of beer (mg GAE/L) and total flavonoid content from 123.36 up to 167.09 milligram of catechin equivalent per liter of beer (mg CE/L). Similar increment was observed within the DPPH scavenging potential, from 46.55 up to 67.16% and total antioxidant power from 139.12 up to 216.67 milligram of butylated hydroxytoluene equivalent per liter of beer (mg BHTE/L). The total phenolic and flavonoid contents and antioxidant activities of extract treated beer showed slight reduction as compared to untreated beer with increasing storage time. According to the findings, M. stenopetala leaf extract could be utilized as a component in beer to reduce oxidation and keep it fresh for extended periods of time.

Among the beer-spoiling microorganisms, the dominant ones belong to the genera Lactobacillus, Leuconostoc, Oenococcus, and Pediococcus. It is assumed that resistance to hop bitters correlates with resistance to other factors and can significantly impact the brewing industry. Beer preservation with high hydrostatic pressure eliminates the spoiling microorganisms while preserving all desired properties of the beer. Here, we present comprehensive in vitro and genomic analysis of the beer-spoiling Lactiplantibacillus plantarum KKP 3573 capacity to resist hop and high hydrostatic pressure. Lp. plantarum KKP 3573 is a strain isolated from spoiled beer. Our finding suggests that the growth rate of the strain depends on the medium variant, where a small concentration of beer (5 IBU) stimulates the growth, suggesting that the limited concentration has a positive effect on cell growth. At the same time, increased concentrations of 20 IBU, 30 IBU, and pure beer 43.6 IBU decreased the growth rate of the KKP 3573 strain. We observed that higher extract content in the pressurized beer increased microbial survivability. The wort and Vienna Lager beer can stimulate the baroprotective effect. The taxonomy of the novel strain was confirmed after whole genome sequencing (WGS) and comparative genomic analysis. More specifically, it contains a chromosome of 3.3 Mb with a GC content of 44.4%, indicative of the Lp. plantarum species. Accordingly, it possesses high genomic similarity (>98%) with other species members. Annotation algorithms revealed that the strain carries several genes involved in resistance to stress, including extreme temperature, hop bitters and high pressure, and adaptation to the brewing environment. Lastly, the strain does not code for toxins and virulence proteins and cannot produce biogenic amines. [ABSTRACT FROM AUTHOR]

The main factor responsible for the sensory aging of beer is the increase in off-flavor aldehydes during beer storage. In pilot brews (200 L) of pale lager beer with different hopping regimes and wort boiling systems, 15 carbonyls were monitored using the GC-MS method. Factor analysis revealed several groups of aldehydes with similar behavior during wort boiling. The concentration of most of them decreased with atmospheric wort boiling and increased with the time and energy-saving pressurized boiling system. Wort clarification was a critical step because of the increase in carbonyl concentration, with the level of most carbonyls being higher in the final wort compared to sweet wort. The hopping regimes only affected the level of 3-methylbutan-2-one in the wort. The concentration of carbonyls decreased significantly (30–90%) during fermentation, except for trans-2-butenal, which increased by 59% on average, likely due to the release from imine complex. The concentration of free aldehydes in the fresh beers was similar for all variants used, but the pressurized wort boiling system could result in lower sensory stability of the beer due to the release of aldehydes from inactive complexes formed during fermentation. This aspect requires further investigation. [ABSTRACT FROM AUTHOR]

The maturation of beer is an important production step with an impact on its quality. Changes in the chemical and sensory profile between 2 and 6 weeks of cold maturation were evaluated in pilot brews (200 l) of a pale lager of 11% and 15% original gravity. In addition to the basic analytical parameters and shelf life, volatiles, hop essential oils, fatty acids, amino acids and stale flavour aldehydes were monitored. The sensory quality of the beers was evaluated using descriptive method. The dynamics of changes in the monitored groups of analytes during maturation of the tested variants was different, but without substantial influence on the overall impression and shelf life of the beer. Under the experimental conditions, it was possible to reduce the maturation time of a common Czech-style lager to 2 weeks of cold lagering. The gradual slight improvement in the overall impression of beers brewed at original gravity indicates the need for a long maturation period to fine-tune the sensory profile of premium lagers. A short maturation period of 2 weeks appears to be beneficial for beers brewed using a high gravity brewing protocol. The findings obtained can be a useful guide for optimising the maturation of Czech-style lager in practice, although the dynamics of changes in the monitored substances and their influence on the sensory characteristics of the beer may be to some degree different when scaled up to operational practice. [ABSTRACT FROM AUTHOR]

The globalisation of the beer market forces brewers to have methodologies that rapidly evaluate the evolution of beer flavour stability. Commonly used forced ageing methods have limitations since temperature and transportation conditions (temperature, vibrations, long-distance travel, and other factors) impact beer quality. This study assessed the prediction power of a forced ageing methodology on the evolution of aldehydes during maritime transportation across four sample groups (maritime transport, storage simulation, and three ageing periods: 7, 21, and 28 days at 37 °C), which differed in their bottle-opening system (either crown cap or ring pull cap). The results revealed that forced ageing up to 28 days could estimate the evolution of phenylacetaldehyde, 3-methylbutanal, 2-methylpropanal, and hexanal during maritime transport. In contrast, the benzaldehyde content was consistently underestimated, on average, 0.8 times lower. In general, the ageing conditions significantly favoured the formation or liberation from a bound state, up to 2.2 times higher, of trans-2-nonenal, acetaldehyde, and 5-hydroximethylfurfural in comparison to the levels registered on exportation simulation beers. Moreover, forced-aged beers with ring pull caps developed quantifiable levels of nonanal and increased phenylacetaldehyde, benzaldehyde, and acetaldehyde content over time. Moreover, thermal stress induced a continuous increase in the extent of beer staling, up to seven times higher, in most samples. [ABSTRACT FROM AUTHOR]

Craft beers with different sensory perceptions have received the attention of more demanding consumers. In this sense, the application of plant extracts as brewing adjuncts is being increasingly studied. Allied with these perspectives is the consumption of lower alcoholic beverages, which also represents the desire for a market niche that has been growing gradually. The present work aimed to produce craft lager beer with the addition of plant extract and reduced alcohol content by partial replacement of malt with malt bagasse. The physical-chemical analyzes of the beer produced showed that it was possible to reduce the alcohol content by 40.5% compared to the control sample. In addition, an extract of Acmella oleracea (Jambu) obtained by supercritical extraction was added to increase the beer's antioxidant capacity. The ABTS, DPPH, and ORAC methods evaluated the antioxidant capacity. These assays were performed again after six months of storage. The quantification and identification of the significant substance in the extract (spilanthol) were performed using Gas Chromatography (GC-FID), Thin Layer Chromatography (TLC), and Attenuated Total Reflectance Infrared Spectroscopy (FTIR-ATR). The results showed significant increases in antioxidant activity compared to the sample without extract. This positive aspect opens a perspective for using jambu flower extract as a prominent antioxidant adjunct in beer. [ABSTRACT FROM AUTHOR]

The aim of this research was to quantitatively evaluate the changes in the physicochemical properties of pale lager beer during a six-month storage period. The measured parameters were: original and apparent extract, specific gravity, alcohol by volume, pH value, color, bitterness, polyphenols, turbidity (haze), dissolved oxygen, carbon dioxide, and foam stability. The beer was filled and stored into four different packaging types: brown glass bottles, polyethylene terephthalate bottles (PET), aluminum cans, and stainless-steel beer kegs, all at a temperature of 20 ± 1.0 °C. There were changes in haze (turbidity), color, and dissolved oxygen values in all of the beer samples stored in the different types of packaging (expressed with the coefficient of variance) with the most significant changes in general found in the beer stored in the PET bottles. The most similar changes were found when correlating changes in beer samples stored in the glass packaging with changes in beer samples stored in kegs (a correlation factor of r = 0.971), while the beer samples stored in glass packaging when compared with the changes in beer samples in PET bottles showed the most change (r = 0.870). [ABSTRACT FROM AUTHOR]

Brewing yeasts have an essential role in beer production as they convert sugar into ethanol and carbon dioxide and impart flavor to beer during brewing. Brewing yeasts can be classified into the following two types: ale yeast (or top-fermenting yeast; Saccharomyces cerevisiae), which is used for ale-type beer production; lager yeast (or bottom-fermenting yeast; Saccharomyces pastorianus), which is used for lager-type beer production. Globally, approximately 90% of beer is produced using lager yeast. The entire genomes of S. cerevisiae S288C and S. pastorianus Weihenstephan 34/70 were sequenced in 1996 and 2009, respectively. Saccharomyces eubayanus, a parent strain of the lager yeast, was discovered in 2011. These advances have markedly contributed to the studies on brewing characteristics and brewing yeast genes and the rapid development of the field of yeast genetics. To contribute to the development of the beer industry, this review summarizes the genetics of brewer's yeast with a special focus on its genomic structure and the genes involved in brewing characteristics. [ABSTRACT FROM AUTHOR]

Innovations and technology are the driving forces for new beer industry products, especially in exploring new flavor profiles. Freeze concentration (FC) emerges as an alternative to take advantage of this opportunity. This work studied the falling‐film freeze concentration (FFFC) application on ethanol–water solutions and commercial beer. The effect of flow rate, freezing temperature, and initial concentration of ethanol in the model solution was studied, and the best conditions were found with a surface response analysis and then applied to a commercial beer. The effect on the sensory profile was determined by multidimensional approximation for the lager beer and the concentrated liquid. A significant effect of initial concentration and freezing temperature were found in the ethanol–water solutions, and the best condition was found at −25°C, 400 L/h, and 0.03 w/w, with a concentration index of 1.35. This condition was evaluated for commercial beer, where a concentration index of 1.18 was achieved, caused by solids in beer and molecular interactions of ethanol with other compounds. The sensory profile of a commercial lager beer was modified by increasing the intensity in 38% of the flavor descriptors and the preservation of the other 41% after applying FFFC. The effect of this technique in beer could be a novel method to produce beer products with new flavor profiles. Practical applications: Innovations in science and technology added to the search for new flavors promote the development of new products in the beer industry. In this article, a potential use of this freeze concentration (FC) technology was identified for the development of new concentrated beer products. The impact of falling‐film FC in a commercial lager beer was studied. First, obtaining a concentrated beer from this technique was possible, with a higher concentration of total solids and ethanol. In addition, the beer's sensory profile was modified by applying FC, which resulted in an increase in the intensity of 38% of the descriptors and the preservation of 41%. It also allowed the appearance of new flavors and aromas. [ABSTRACT FROM AUTHOR]

Headspace solid-phase microextraction coupled to gas chromatography-mass spectrometry (HS-SPME/GC-MS), sensory evaluation, and multivariate analysis were applied to monitor and compare the evolution of the aromatic profile of a lager beer in different types of containers (aluminum cans and glass bottles) during the natural ageing process. Samples were aged naturally for a year in the absence of light with a controlled temperature of around 14 °C +/− 0.5 °C. The sensory evaluation applied was a blind olfactometric triangle test between canned and bottled samples at different periods of aging: fresh, 6 months, and 11 months. The sensory evaluation showed that the panelists were able to differentiate between samples, except for the fresh samples from the brewery. A total of 34 volatile compounds were identified using the HS-SPME/GC-MS technique for both packaging types in this experiment. The application of multivariate analysis to the GC-MS data showed that the samples could not be differentiated according to the type of packaging but could be differentiated by the ageing time. The results showed that the combination of sensory, HS-SPME-GC-MS, and multivariate analysis seemed to be a valuable tool for monitoring and identifying possible changes in the aroma profile of a beer during its shelf life. Furthermore, the results showed that storing beer under optimal conditions helped preserve its quality during its shelf life, regardless of the type of packaging (aluminum can and glass bottle). [ABSTRACT FROM AUTHOR]

Beer production is the largest among alcoholic beverages. Its production process is complex and demands several steps. Lager beers commonly present an off-flavor of butter that is due to the presence of diacetyl, and to avoid such a problem, a long period of maturation (3–5 weeks) is required. Another way is the application of (α-acetolactate decarboxylase) ALDC to accelerate the process. The objectives of the present work were to develop a low-cost support using gelatin, a residue from capsules from the nutraceutical industry, to immobilize the ALDC enzyme. For this, the yield, efficiency and activity recovered, and the stability of free and immobilized enzymes at different temperatures and pH were evaluated. To evaluate the capacity of immobilized enzymes when applied directly to beer and their operational stability, three concentrations of glutaraldehyde (1%, 2.5% and 5%) were tested in distilled water as a cross-linking agent. The best results obtained were 95.6%, 27.0% and 23.6%, respectively, for yield, efficiency and activity recovery. Immobilization provided a high activity over a wide pH range. The immobilized enzyme showed greater stability at temperatures of 50 and 60 °C. The immobilized derivative showed adequate reuse capacity, and its dehydrated form had excellent activity after long periods of storage. [ABSTRACT FROM AUTHOR]

Non-Saccharomyces yeasts represent a very appealing alternative to producing beers with zero or low ethanol content. The current study explores the potential of seven non-Saccharomyces yeasts to produce low-alcohol or non-alcoholic beer, in addition to engineered/selected Saccharomyces yeasts for low-alcohol production. The yeasts were first screened for their sugar consumption and ethanol production profiles, leading to the selection of strains with absent or inefficient maltose consumption and consequently with low-to-null ethanol production. The selected yeasts were then used in larger-scale fermentations for volatile and sensory evaluation. Overall, the yeasts produced beers with ethanol concentrations below 1.2% in which fusel alcohols and esters were also detected, making them eligible to produce low-alcohol beers. Among the lager beers produced in this study, beers produced using Saccharomyces yeast demonstrated a higher acceptance by taster panelists. This study demonstrates the suitability of non-conventional yeasts for producing low-alcohol or non-alcoholic beers and opens perspectives for the development of non-conventional beers. [ABSTRACT FROM AUTHOR]

The evaluation of the biogenic amines (BAs) profile of different types of craft beers is herein presented. A previously developed and validated analytical method based on ion-pair chromatography coupled with potentiometric detection was used to determine the presence of 10 BAs. Good analytical features were obtained for all amines regarding linearity (R2 values from 0.9873 ± 0.0015 to 0.9973 ± 0.0015), intra- and inter-day precision (RSD lower than 6.9% and 9.7% for beer samples, respectively), and accuracy (recovery between 83.2–108.9%). Detection and quantification limits range from 9.3 to 60.5 and from 31.1 to 202.3 µg L−1, respectively. The validated method was applied to the analysis of four ale beers and one lager craft beer. Ethylamine, spermidine, spermine, and tyramine were detected in all analyzed samples while methylamine and phenylethylamine were not detected. Overall, pale ale beers had a significantly higher total content of BAs than those found in wheat pale and dark samples. A general least square regression model showed a good correlation between the total content of BAs and the brewing process, especially for Plato degree, mashing, and fermentation temperatures. Knowledge about the type of ingredients and manufacturing processes that contribute to higher concentrations of these compounds is crucial to ensuring consumer safety. [ABSTRACT FROM AUTHOR]

This study investigated the effects on beer colloidal stability of full-scale brewing with adjuncts, enzymes, and finings. Industrial lager beers were produced solely from barley malt or from barley malt with adjuncts (corn grist and starch syrup or unmalted barley). Various stabilization aids were also used (silica gel, PVPP, proline-specific endoprotease, carrageenan). Predictive shelf-life tests were conducted. We analyzed the content of compounds (proteins and polyphenols) generally related to beer colloidal stability. The results show that the haze-forming potential of the beer during storage can be evaluated based on the coagulable nitrogen content (high molecular weight proteins), rather than the total nitrogen content and polyphenol content. A very strong and statistically significant negative correlation was observed between the concentration of coagulable nitrogen and beer colloidal stability. When brewing was conducted with 49% barley raw material and exogenous proteases, especially proline-specific endoprotease, the coagulable nitrogen content fell and beer colloidal stability improved. The use of corn grist and starch syrup as up to 40% of the total grist resulted in a 30% longer physical shelf life compared to the all-malt beer. [ABSTRACT FROM AUTHOR]

The present study aims at the sustainable use of bakery leftovers and their application as a partial substitute for malt in beer production. We made seven samples of Lager beer where we substituted malt with up to 60 % of bread, three samples of Brown Ale with up to 50 % of bread, and four samples of Porter with up to 80 % of bread. We made a sensory evaluation of the finished beer and determined its chemical composition. Water plays an important role in beer quality, especially in the sensory profile. We did a chemical analysis of the water to compare its chemical profile with that of the brewed beer. Samples with bread that substituted malt up to 30 % showed satisfactory results in the total rating of sensory evaluation. The results of chemical measurement show that the more bread, the saltier the taste of the beer due to the increased Na and Clindicators. Therefore, we suggest not using more than 30 % of bread because the salty taste can be more distinct. We noticed that the quantity of K depends on the type of fermentation and the availability of bread decreases the quantity of the element. We also measured foam stability and beer colour; the results serve as indicators of beer quality. We found that the beer colour and the foam quality in top-fermented beers are not affected by bread. We calculated that 30 % substitution with bakery leftovers could save around 6 - 7.5 kg of barley per 1 hl. Brewers can collect bread leftovers from local supermarkets, cafeterias, etc. [ABSTRACT FROM AUTHOR]

The fresh flavor of a beer brand is one of its most important quality parameters and should be retained as long as possible through shelf-life. Early stages of beer production can have significant impacts on beer flavor stability. The use of cereal adjuncts – either malted or unmalted – is now widespread practice in brewing. This laboratory mashing study investigated the impacts of incorporating common solid adjuncts (corn and rice) at increasing grist percentages (0-50%) on flavor stability indicators measured in wort. Sweet worts were analysed for metal ion levels (ICP-MS), thiol content (RP-HPLC), oxidative stability (EPR spectroscopy), staling aldehydes (HS-SPME-GC-MS), trihydroxy fatty acids (GC-FID), t-2-nonenal potential (GC-MS), color and thiobarbituric acid (TBI). Mashing conditions for each formulation were adjusted in order to achieve target FAN values. Unmalted rice or corn adjuncts significantly reduced the total metal ion content, color, TBI and staling aldehydes in sweet worts at 50% adjunct incorporation (p < 0.05), relative in each case to the respective all-malt control mash. Our findings showed that unmalted rice or corn adjunct incorporation generally improved flavor stability metrics in sweet worts when similar mashing conditions were applied, whilst increasing the length of the 'protein stand' in mashing to reach target FAN in general had a negative impact on flavor stability indicators – e.g., wort T150 values significantly decreased in each recipe at 25% and 35% adjunct relative to the 12.5% adjunct brew but increased again at 50% adjunct, presumably due to the prolonged proteolytic stand employed to achieve target FAN content. [ABSTRACT FROM AUTHOR]

Beer ranks third in terms of consumption worldwide, and its technology is constantly being improved and perfected. The boom in craft brewing has led to the production of thousands of new types of beer, but most often without scientific justification of the technological decisions made. This paper discusses the approaches to the modeling of the composition of the malt mixture and the mode of lager beer production. A special cubic simplex-lattice design with two replications was used to model the mixture with three malt types: Pilsner, Caramel Pils and Caramel Munich type 2. Models for the main brewing characteristics, i.e., wort extract and color, as well as models for the biological parameters of the mash, i.e., phenolic compound content and antioxidant potential, were developed using different methods. Multi-objective optimization was carried out and a specific mixture was developed for the production of lager beer. The influence of acidulated malt, lactic acid and CaCl2 additions on the extract yield and malt mash filtration time were established through one-factor experiments. The extract and fermentable sugar yield during individual pauses in the mashing mode was studied with a view to its optimization.

One of the most popular and widely consumed drinks in the world is beer, also one of the oldest in the human mankind. The consummation of the drink has deep historical roots and there are many traditions, especially in Europe such as beer festivals, beer-oriented tourism, and beer drinking games. Although beer is extremely popular in human society, it actually can act as a pesticide - more specifically as a molluscicide approved by the European Commission as a basic substance in 2017 to be used as a molluscicide in traps. In this study the insecticidal effects of popular brands of light beer type „lager" in Bulgaria: „Pirinsko Svetlo”, „Zagorka”, „Astika” and „Kamenitza” with alcohol content: 4.3% (v/v), 5% (v/v), 4.5% (v/v) and 4.4% (v/v) were investigated towards different aphid species. The beer was tested in the original form and with dilution with water: 90%, 80%, 70%, 50%, etc. The conducted trials prove that beer without any dilution can be 100% effective against aphid species: Aphis rosae, Aphis pomi, Myzus cerasi, Aphis nerii, Aphis gossypii. Mortality rate after 24 hours was 100% for all aphid species and all used in the tests beer trade marks were able to achieve this. There were no significant differences (p>0.05) between results received from tests with different aphid species and from different beer trademarks. In this aspect, the cheapest beer available on the local market can provide a safe, low cost, environmental and effective way of pest management in the small gardens, urban agriculture or plants in public spaces like airports, stations, offices, etc. [ABSTRACT FROM AUTHOR]

Craft breweries tend to use special raw materials and also special ingredients (spices, herbs, fruits) to typify beers, but the metabolic activities of yeasts play a primary role in defining the sensory characteristics of this beverage. Saccharomyces cerevisiae and Saccharomyces pastorianus are yeast species usually used for ale and lager beer production. The selection and use of new yeast starters with peculiar technological and enzymatic characteristics could represent the key point for the production of beers with good and distinctive organoleptic properties. In this study, the fermentative performance of S. cerevisiae 41CM yeast isolated from the vineyard environment for ale and lager craft beer production on a laboratory scale was evaluated. The commercial yeast S. cerevisiae Fermentis S-04 and S. pastorianus Weihenstephan 34/70 were used as reference strains. S. cerevisiae 41CM showed fermentative kinetics similar to commercial starters, both in lager (12 °C) and ale (20 °C) brewing. In all beers brewed, the largest percentage of volatile compounds synthesized during the fermentation were alcohols, followed by esters, terpenes, and aldehydes. In particular, S. cerevisiae 41CM starter contributed a higher relative percentage of esters in the ale beer than that detected in the lager beer, without ever synthesizing unwanted volatile compounds. [ABSTRACT FROM AUTHOR]

Non-domesticated, wild Saccharomyces yeasts have promising characteristics for beer diversification, particularly when used in the generation of de novo interspecific hybrids. A major motivation for the current work was the question whether attractive novel Saccharomyces interspecific hybrids can be created for the production of exotic lager beers without using the genomic resources of the ale yeast Saccharomyces cerevisiae. Importantly, maltotriose utilization is an essential characteristic typically associated with domesticated ale/lager brewing strains. A high-throughput screening on nearly 200 strains representing all eight species of the Saccharomyces genus was conducted. Three Saccharomyces mikatae strains were able to aerobically grow on maltotriose as the sole carbon source, a trait until recently unidentified for this species. Our screening also confirmed the recently reported maltotriose utilization of the S. jurei strain D5095T. Remarkably, de novo hybrids between a maltotriose-utilizing S. mikatae or S. jurei strain and the maltotriosenegative Saccharomyces eubayanus strain CBS 12357T displayed heterosis and outperformed both parents with regard to aerobically utilizing maltotriose as the sole source of carbon. Indeed, the maximum specific growth rates on this sugar were comparable to the well-known industrial strain, Saccharomyces pastorianus CBS 1513. In lager brewing settings (oxygen-limited), the new hybrids were able to ferment maltose, while maltotriose was not metabolized. Favorable fruity esters were produced, demonstrating that the novel hybrids have the potential to add to the diversity of lager brewing. [ABSTRACT FROM AUTHOR]

Breweries can have up to 30 % beer loss due to process inefficiencies. Recently, hop extracts have been explored to offer standardized, cost-effective and a sustainable alternative to brewers. This study aimed to test new hop extracts applied in three main beer styles to showcase potential advantages to brewing. Hop extracts were applied into: 1) one lager wort stream for differentiation into lager and ale beers; into 2) one non-alcoholic beer, and into 3) one specialty beer style, Indian Pale Ale (IPA). Following the application of selected hop extract blends, the resulting beers were submitted to sensory analysis and their profiles compared. Results showed that, when applied to lager wort, brewing solely with hop extracts (naturally pre-isomerized bittering and post-fermentation aroma extracts) successfully delivered true-to-style lager and ale beer profiles. Bittering hops from alpha and beta skewed the aroma towards floral/herbal and citrus/lemon, respectively. Aroma hop extracts contributed towards citrus enhancement in lager, and stone fruit/floral in ale. Overall, hop extracts improved hop bill efficiency when compared to hop pellets. In non-alcoholic beer, sweetness was modulated, worty notes masked, and mouthfeel improved. In IPA, a blend of post-fermentation extracts (Amarillo®/Cascade/Citra®) significantly increased positive attributes (fruity, sweet, floral, and citrus). Also, it was possible to deliver a characteristic dry hop taste impact, while significantly reducing the brewing time. The selected hop extract blend delivered positive taste impact across all beer applications. [ABSTRACT FROM AUTHOR]

The scope of the study was the evaluation of the selected physicochemical (O2 and CO2 contents, bitterness, color, total polyphenol content (TPC), turbidity, foaming stability) and sensory properties of Czech lager beer with different original wort extract (OWE) values (OWE of 10.0; 11.0; 11.5; 12.0% w/w) during a cold storage period of 6 months (4 ± 2 °C). The length of the cold storage period did not influence the values of dissolved O2 and CO2, bitterness, color and foam stability of the samples. Contrarily, the TPC, turbidity, and sensory attributes of the samples were affected by the course of cold storage. The OWE values did not affect the development of the parameters tested. All beer samples stored until the 5th month presented "very good" sensory characteristics. Cold storage of beer is advantageous in order to maintain its freshness and sensory attributes at the highest level for the final consumer. [ABSTRACT FROM AUTHOR]

[Display omitted] • New approach to beer analysis using the precepts of green analytical chemistry. • Use of microdistillation to determine total vicinal diketones (VDK) • Determination of VDK in different types and styles of industrial and craft beers. Vicinal diketones (VDK) strongly affect the quality of beers, as they are responsible for off-flavors and deterioration markers, which are recognized as safe for humans when ingested but are toxic when inhaled. Thus, their determination is required in both the production process and the final beverage. A novel approach for determining the total VDK content in beers using microdistillation as a simple approach for sample pretreatment is proposed. The lab-made microdistillation apparatus consists of a capped Falcon® tube with the sample at the bottom and the acceptor solution inside a suspended Eppendorf® tube. The sample is heated (90 °C, 20 min) to volatilize the analytes, which are collected from the headspace by an acceptor-derivatizing solution (o-phenylenediamine in acid medium), and the product is determined by ultraviolet spectrophotometry. Under conditions optimized by experimental design, a linear response was achieved from 0.05 to 1.00 mg L-1 diacetyl, with a coefficient of variation (n = 11) and limit of detection (95 % confidence level) estimated at 4.3 % and 0.01 mg L-1 diacetyl, respectively. The procedure requires as low as 40 μg of o-phenylenediamine, 1.7 μL of 37 % (v/v) hydrochloric acid, and 5000 μL of sample, generating only 5400 μL of waste per determination. It allows for the simultaneous analysis of 10 samples, a capability not previously reported in the literature. Results obtained for Ale and Lager beers using the proposed and reference procedures agreed at a 95 % confidence level. Therefore, the current proposal is a reliable and environmentally friendly alternative for the rapid determination of VDKs in beer, contributing to improved quality control in both the process and final products of the brewing industry. [ABSTRACT FROM AUTHOR]

Beer melanoidins, the final products of the Maillard reaction (MR), play a critical role in determining the flavor stability of beer due to their antioxidant properties. This study investigated the structure, stability, and antioxidant activity of lager beer melanoidins (LBM) and ale beer melanoidins (ABM). The results revealed that ABM possessed a higher browning index and molecular weight, attribute to its relatively intense MR. However, this intensity also led to a more unfolded and disordered structure in ABM. Conversely, LBM outperformed ABM in the FAST index, thermal stability, and total antioxidant activity because the low alcohol content in lager beer reduced oxidation and thermal degradation while boosting the stability and antioxidant activity of melanoidins. As a result, it would offer a novel possibility to improve beer flavor stability by optimizing the brewing process to modify the structural and functional characteristics of melanoidins. [Display omitted] • Beer melanoidin structure were caused by the Maillard reaction during the brewing. • Beer melanoidin's α-helix unwound as the Maillard reaction intensified. • Lager beer's melanoidin has better stability and antioxidant capacity than ale. • Elevated alcohol and temperature reduced beer melanoidin's stability and function. • Different beers' melanoidin antioxidant capacity overall followed a similar pattern. [ABSTRACT FROM AUTHOR]

The aim of this work was to study the effect of a recombinant superoxide dismutase (rSOD) from Bacillus pumilus E−1-1-1 regarding the degradation of aflatoxin M 1 (AFM 1) in model solution. The degradation mechanism was further explored and applied in milk and beer. The Kinetic Momentum and maximal velocity of the rSOD towards AFM 1 were 3.6 μg/mL and 1.8 μg/mL/min, respectively. The rSOD-mediated AFM 1 degradation product was identified as C 12 H 11 O 3. Molecular docking simulation suggested that hydrogen bonds, van der Waals interaction, and pi bond played major roles in the steadiness of AFM 1 -rSOD. Meanwhile, compared with identical concentration of AFM 1 , the survival rate of Hep-G2 cells treated with superoxide dismutase-generated AFM 1 degradation products increased about 1.6 times. In addition, the degradation rates in lager beer and milk were 15.19% and 26.03%, respectively. Therefore, the rSOD has great modification value to accommodate AFM 1 degradation in beer and milk. This study indicates a direction to be followed for future degrading AFM 1 in food. • Superoxide dismutase from Bacillus pumilus E−1-1-1 chould degrade aflatoxin M 1. • AFM 1 (C 17 H 12 O 7) was transformed into C 12 H 11 O 3. • C 12 H 11 O 3 showed significantly reduced toxicity to human liver cancer cells Hep-G2. • The enzyme could partially degrade AFM 1 in milk and beer. [ABSTRACT FROM AUTHOR]