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In this study, the process of the vacuum impregnation of Kangoo barley grain, at the stage of soaking, was used in the production of light malt. The influence of vacuum impregnation on the speed of the water uptake by the barley, at temperatures of 12, 14, 16 and 18 °C, was also analyzed. At this stage of the research, the grain was soaked in water to obtain a moisture content of approximately 42%. The samples for the moisture content tests were taken every 2 h. The grain intended for malt was soaked in an air–water system and was kept submerged in water for 6 h. It was then removed from the water and kept for 18 h. The grain was aerated during the soaking process. The malting and soaking lasted eight days at temperatures of 12, 14, 16 and 18 °C. The samples for further testing were taken daily. Then, each of the samples was dried, following the same procedure. The sprouts were removed immediately after the dried samples contained approximately 4% moisture. Following a 3-month maturation process, the congress wort was produced from the malt. The pH and the extract content in the wort were tested. It was found that the process of vacuum impregnation significantly accelerates the uptake of water by the grain. In almost all cases, the influence of the tested factors on the pH of the wort and the extract content was also observed.

Approximately 25% of all carbohydrates in industrial worts are poorly, if at all, fermented by brewing yeast. This includes dextrins, β-glucans, arabinose, xylose, disaccharides such as isomaltose, nigerose, kojibiose, and trisaccharides such as panose and isopanose. As the efficient utilization of carbohydrates during the wort’s fermentation impacts the alcohol yield and the organoleptic traits of the product, developing brewing strains with enhanced abilities to ferment subsets of these sugars is highly desirable. In this study, we developed Saccharomyces pastorianus laboratory yeast strains with a superior capacity to grow on isomaltose and panose. First, we designed a plasmid toolbox for the stable integration of genes into lager strains. Next, we used the toolbox to elevate the levels of the α-glucoside transporter Agt1 and the major isomaltase Ima1. This was achieved by integrating synthetic AGT1 and IMA1 genes under the control of strong constitutive promoters into defined genomic sites. As a result, strains carrying both genes showed a superior capacity to grow on panose and isomaltose, indicating that Ima1 and Agt1 act in synergy to consume these sugars. Our study suggests that non-GMO strategies aiming to develop strains with improved isomaltose and panose utilization could include identifying strains that overexpress AGT1 and IMA1. [ABSTRACT FROM AUTHOR]

The mashing step underpins the brewing process, during which the endogenous amylolytic enzymes in the malt, chiefly β-amylase, α-amylase, and limit dextrinase, act concurrently to rapidly hydrolyze malt starch to fermentable sugars. With barley malts, the mashing step is relatively straightforward, due in part to malted barley’s high enzyme activity, enzyme thermostabilities, and gelatinization properties. However, barley beers also contain gluten and individuals with celiac disease or other gluten intolerances should avoid consuming these beers. Producing gluten-free beer from gluten-free malts is difficult, generally because gluten-free malts have lower enzyme activities. Strategies to produce gluten-free beers commonly rely on exogenous enzymes to perform the hydrolysis. In this study, it was determined that the pH optima of the enzymes from gluten free malts correspond to regions already typically targeted for barley mashes, but that a lower mashing temperature was required as the enzymes exhibited low thermostability at common mashing temperatures. The ExGM decoction mashing procedure was developed to retain enzyme activity, but ensure starch gelatinization, and demonstrates a modified brewing procedure using gluten-free malts, or a combination of malts with sub-optimal enzyme profiles, that produces high fermentable sugar concentrations. This study demonstrates that gluten-free malts can produce high fermentable sugar concentrations without requiring enzyme supplementation. [ABSTRACT FROM AUTHOR]

Cereal grain as an output product in beer production might be contaminated by pesticides used for crop protection, which are then transferred into beer. Therefore, the aim and novelty of this comprehensive study was the multistep assessment of the herbicide, fungicides, and insecticides transfer from unprocessed wheat grain to malt, mash, boiled wort, wort boiled with hops and beer according to pesticide physicochemical properties. The results indicated that the highest reduction of the herbicide prosulfocarb (86 %), insecticide cypermethrin (79 %), and fungicide thiophanate-methyl (88 %) were noticed during malting. The highest processing factor in mash was determined for benzimidazole fungicide (0.61). Triazoles and strobilurin were degraded to the greatest extent in beer (96 %). The principal component analysis revealed that molar mass and octanol-water partition coefficient are the most correlated with the effectiveness of pesticide reduction. The results of this study are crucial in the beer industry and enable an increase in consumer safety. • Twelve commonly occurred pesticides in wheat were tested in 5 steps of beer brewing. • Triazoles and strobilurins were most successfully reduced. • Pesticides reduction was the most effective in malt and beer. • Processing factors (PF) ranged from 0.04 in beer to 0.68 in wort boiled with hops. [ABSTRACT FROM AUTHOR]

Huaimi is a precious Chinese herbal medicine mainly containing rutin. In this study, Cyan Huaimi (CH) and Golden Huaimi (GH) were introduced at various stages of beer production. A total of 8 beer groups and 1 control group were set up to compare their physicochemical, bioactivity, volatile compounds and sensory characteristics. The results indicated that compared with the control group, adding Huaimi significantly reduced the pH and real extract of beer, and improved the other Physicochemical parameters. Furthermore, the addition of Huaimi brought higher levels of total polyphenols, flavonoids, and phenols compounds in 8 beer groups, particularly rutin content, reaching as high as 212.69 mg/L. Moreover, through the evaluation of DPPH, ABTS, and reducing power methods revealed that adding Huaimi at the boiling stage benefited most in improving antioxidant capacity. However, the results of sensory evaluation demonstrated that panelists preferred the beer with Huaimi added at the saccharification stage because of its smoother foam. Volatiles analysis revealed that adding Huaimi introduced twelve new volatiles to the beer, enhancing its flavor and taste complexity. • Incorporation of Huaimi to brewing process expanded the using range of it in food. • The cultivars and addition process of Huaimi affected the quality of beer. • Huaimi increased the rutin content and enhanced the antioxidant capacity of beer. • Huaimi brought unique volatiles and preferable sensory characteristics to beer. [ABSTRACT FROM AUTHOR]

Background. There is much promise in technologies which may speed up time-consuming processes such as preparing seed yeast, primary fermentation and improving beer quality in the brewing industry. This study focuses on the activating and disintegrative effect of ultrasound with a 44 kHz frequency and a 1.0 W/cm2 intensity on brewer's yeast. Materials and methods. This study established that ten-minute ultrasonic treatment of yeast is sufficient to reach the stimulating effect. Further ultrasonic treatment is irrelevant since the percentage of dead cells in the yeast suspension exceeds the permissible levels (more than 10%). The experiment showed that two-minute ultrasonic treatment improved the physiological activity of seed yeast and shortened the time for producing seed yeast by 12 hours. Ultrasonic disintegration allowed a yeast extract to be obtained from the brewer's spent yeast. Ultrasound was applied to the yeast suspension for 19 minutes. Results. The obtained yeast extract was used for additional nutrition in preparing seed yeast. It was found that the added yeast extract (2% of the total volume) shortened the time for preparing seed yeast by 6 hours due to the improved physiological state of the yeast. At the final stage, two-minute ultrasonic treatment and yeast extract (2% of the total volume) were used to activate the seed yeast. Conclusion. The seed yeast activation shortened the time for preparing seed yeast by 18 hours, and for the primary fermentation by 24 hours, while also improving the quality of the beer. [ABSTRACT FROM AUTHOR]

Copyright of Studii de Ştiintă şi Cultură is the property of Studii de Stiinta si Cultura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Grains of four pearl millet hybrids v/z.HHB-60, HHB-67, HHB-94 and HHB-146 were analyzed for starch, crude protein and ether extract content to know their suitability for beer production. Pearl millet hybrid HHB-67 with highest starch content of 56.88 % and less crude protein (12.70 %) and ether extract (7.8 %) among all hybrids was selected for amylolytic enzyme activation during malting. A steeping period of 10 h with 72 h of germination period at 200C resulted into highest alpha-amylase (96.12 DUN units) and beta-amylase (179.63 pmole of glucose/g of green malt) activity. Among various wort samples prepared with differential grit combinations of pearl malt, the 100% pearl millet wort had lower extract and reducing sugars than control barley wort. Fermentation of hopped pearl millet wort (100%) with Saccharomyces uvarum NCDC-48 at a pitching rate of 0.3 % (w/v) generated beer with 3.5 % (v/v) alcohol content comparable with control barley beer (3.6 %v/v). [ABSTRACT FROM AUTHOR]

Background. In recent years, increasing health awareness in consumers has motivated breweries to expand their beverage ranges with products with increased biological value. The aim of the present research was to develop probiotic wort-based beverages with grapefruit or tangerine zest essential oil addition. Materials and methods. Wort was produced with 60% Pilsen malt, 20% Vienna malt and 20% Caramel Munich II malt with and without the addition of 0.05% (v/v) grapefruit or tangerine essential oils. It was inoculated with the probiotic yeast strain Saccharomyces cerevisiae var. boulardii Y1. Fermentations were carried out at a constant temperature of 10°C for 5 days. The dynamics of the extract, the alcohol content and the concentration of viable cells were monitored daily. The total phenolic content, phenolic acid and flavonoid phenolic compounds were determined because of their antioxidant activity. The antioxidant activity was determined by radical scavenging assay (DPPH) and ferric reducing antioxidant power (FRAP). A descriptive organoleptic evaluation of the final beverages was performed. Results. The essential oils inhibited yeast growth to some extent at the beginning of the fermentation, even at a concentration of 0.05% (v/v), which resulted in lower alcohol content in the beverages with essential oil addition. Nevertheless, at the end of fermentation the concentration of viable cells was almost equal in all the beverages. Tangerine essential oil addition led to the highest content of phenolics, of which phenolic acids predominated. Therefore, the highest antioxidant activity of the beverage with tangerine essential oil can be ascribed to phenolic acids. The results of the sensorial evaluation also showed that the panel had preference towards the beverage with tangerine essential oil. Conclusion. The combination of essential oil and the probiotic yeast strain resulted in beverages with higher biological value than the beverages produced with the probiotic strain alone. The results obtained will be used for optimisation of process variables in the production of pilot-scale wort-based probiotic beverages with essential oil addition. [ABSTRACT FROM AUTHOR]

Malt is the major source of iron (Fe) and copper (Cu) in wort and beer, and the main uptake of Fe and Cu ions happens during mashing. Past research has indicated that the mineral composition of sweet wort primarily depends on the ion removal rate during mash filtration. In this study, the capacity to remove Fe and Cu during mashing has been evaluated. Each metal was added (50 µM) at the beginning of congress mashings and the final concentrations in sweet wort were determined using inductively coupled plasma optical emission spectroscopy (ICP-OES). There was little to no difference between the samples spiked with Fe and the blanks when using pure pilsner malt, suggesting that there is an efficient binding of Fe in the spent grains. A significant, but not complete, removal was also observed for Cu-spiked samples. Mashing with roasted malt showed decreased removal of Fe while removal of Cu was increased. The effects of addition of high metal concentrations during mashing on the oxidative stability of the sweet wort were evaluated using electron spin resonance (ESR) spectroscopy and oxygen consumption. It was concluded that the spent grains have an important leveling effect on the final Fe and Cu concentrations in sweet wort, which also levels the effects on oxidative reactions. [ABSTRACT FROM AUTHOR]

The objective of the present work is to study the behavior of a helical tube and shell heat exchanger, for the cooling of the wort in the process of making craft beer with cold water, through the methodology of computational fluid dynamics (CFD) by finite volume models for heat exchanger modeling. This by using the ANSYS Fluent software, which allows to understand the behavior of the fluid through equations that describe their movement and behavior, using numerical methods and computational techniques. In the mesh convergence, two methods were used, orthogonality and obliquity, with which it was confirmed that the meshing is ideal in the simulations that were carried out. For the simulation, the k-epsilon turbulence model and the energy model were used. Through various simulations, it was obtained that by varying the mass flow, better results are reducing the outlet temperature, with a variation of 15.16 °C, while varying the inlet temperature of the water, there is just a variation from 2.71 °C to 0.01 °C. Therefore, a significant improvement in the performance of the heat exchanger was found. In the same way, it was confirmed that the number of spikes in the heat exchanger is adequate, since the outlet temperature would not be reached with less spikes.

The content of ascorbic acid and phenolic substances in natural juices and unfortified wine materials from garden strawberries of Polka and Pegas varieties was investigated. The content of ascorbic acid was 271-417 mg/dm3 and of phenolic substances – 1280-1500 mg/dm3. The content of these ingredients depends on the variety characteristics (dominant influence) and the weather conditions of the growing season. 230 g of white sugar was added to one dm3 of strawberry juice for the production of unfortified wine materials intended for sweet wines. The wort was pasteurized at 85°C for 5 minutes, cooled and fermented using active dry yeast: the race EC 1118 (France), ENSIS LE-C1, ENSIS LE-1, ENSIS LE-5, ENSIS LE-6 (Spain) in accordance with the manufacturer's recommendations. It has been found that the content of ascorbic acid and phenolic substances decreases during wort preparation and fermentation. The average loss of ascorbic acid during wort preparation is 17.4% and of phenolic substances – from 1.1 to 4.9%. The reduction in the content of these components due to the dilution of sugar during wort preparation is 14-15%. The duration of fermentation of strawberry worts with an initial mass concentration of invert sugars 274 g/ dm3 is 70-77 days. The output of cleared wine material after fermentation depends on the variety characteristics, the year conditions and the yeast race used, and ranges from 86.9 to 92.7%. Loss of ascorbic acid during wort fermentation averages 49.3%, phenolic substances 21.6%. Ascorbic acid content of 86-158 mg/dm3 and phenolic substances of 720–1080 mg/dm3 were found in unfortified strawberry wines. In particular, according to the average data of two years, the content of phenolic substances in the wine materials from strawberries of the Polka variety were 197 mg/dm3 higher than their content in the wine materials from the berries of the Pegas variety. The content of ascorbic acid in wine materials in relation to the content in the juices corresponding to fresh berries is 25.4-41.3%, on average – 33.6%; of phenolic substances – 56.2-72.0%, on average 62.6%. In order to better preserve the ascorbic acid, the ENSISLE-C1 yeast race (Spain) and the phenolic substances EC-1118 (France) should be used. The results of studies confirm that unfortified sweet wines from wild strawberries can be attributed to the products with health-promoting properties.

The aim of this study was to determine the effect of yeast harvest timing on the process performance, total yeast count and the content of volatile components in beer. The experiments were performed on an industrial scale with fermentation and maturation conducted in three fermentation tanks with a capacity of 3800 hl (cylindro-conical tanks - CCT). All processes were carried out using the same technological conditions. The worts were aerated with sterile air and yeast after the second fermentation (third generation) was added. The duration of the maturation phase and the processes of the yeast harvest were conducted at different times (1st, 4th and 6th day) after finishing the primary fermentation process. During fermentation and maturation, changes in the contents of the extract, yeast, and volatile components were investigated. These experiments showed that the use of different times during yeast harvest had a significant impact on the course of fermentation and maturation and impact on the total yeast count during the maturation process and on the amount of volatile components in beer. With a delay in the start of yeast cropping, the content of acetaldehyde and vicinal diketones decreased and the content of esters increased. The timing of the yeast crop significantly influenced the final beer quality.

Triticale accounts for the biggest share in gross processing and state procurement of grain in Belarussian production of alcohol. The main difficulty in its processing is the formation of viscous technological fluids due to the presence of non-starch polysaccharides in its chemical composition. All measures taken to solve the problem come down to the selection of the efficient enzyme preparations, hydrolyzing grain polymers into low molecular weight compounds, which have the ability to be disposed by the yeast cells and form the ethyl alcohol. But grain own enzymes are not involved. It is possible to solve the problem by means of biological activation, which will activate grain enzyme systems and partially hydrolyze grain polymers into low molecular weight compounds. The article considers general and special technological parameters of six cultivars of triticale selected in the Republic of Belarus: Antos, Kastus, Dubrava, Run, Prometheus, Impulse. The authors determined that the most promising cultivars for bioactivation and food grade ethyl alcohol production are Antos and Dubrava. The authors explored the possibility of using hot soaking of triticale grain for the biological activation. They also showed the advantages of introduction of amaranth green mass in the amount of 8% during hot soaking for the reduction of grain microbiological contamination. They studied the changes in the technological properties of triticale cultivars Antos and Dubrava after the bioactivation with the green mass of amaranth. The authors determined that grain microbiological characteristics improved, the activity of grain enzymes increased, proportion of low molecular weight compounds in the chemical composition increased. They studied the processes taking place during wort and mash production from the bioactivated triticale grain. The authors showed that the processing of bioactivated triticale grain resulted in the production of wort with higher concentration of dry matter which allowed to increase the ethanol content in the mature mash produced from triticale cultivar Antos by 19.5% and from the triticale cultivar Dubrava by 29.3% and reduce the total quantity of the main impurities in distillates.

For the production of distillates from Jerusalem artichoke, the technical and economic advantages of using dried raw materials are substantiated in comparison with the processing of fresh tubers, consisting in stabilizing the biochemical composition of raw materials and increasing its microbiological characteristics, eliminating seasonality, simplifying the technological process. The fractional composition of fructose containing carbohydrates of raw materials was studied and it was shown that in the process of obtaining dried Jerusalem artichoke, the main carbohydrates of raw materials depolymerize and, as a result, their accessibility to enzymatic hydrolysis is increased. The content of free reducing sugars (fraction FI) increases by 3–5 times, low molecular weight fraction of inulin (fraction FII) by 1.5 times. The albumin complex of dried Jerusalem artichoke is analyzed and it is established that the main protein fractions are albumins (58.2–61.5 % of total protein nitrogen), prolamines and glutelins are not found in the raw material. The factors influencing the technological parameters of the two-stage method for preparing dried artichoke for distillation are determined. At the first stage, when obtaining the sugared wort, a hydromodule (1 ÷ 4.5) was installed, the norm of the microbial inulinase task (3.0–4.5 units in/g inulin of the raw material), the duration of the enzymatic treatment (3 hours at a temperature of 52 ± 2 °С). Based on the study of the dynamics of CO2 emissions, the evaluation of the strength of fermented wort and the determination of volatile components in it, it is recommended to use dry alcoholic yeast Fermiol in the amount of 100 mg /100 g of wort, the process at a temperature of 28–30 °С, the fermentation time is 72 hours. it is shown that acidification of the medium in the wort preparation stage to pH 4.5 allows to reduce methanol content in the fermented wort.

Pulse (Fabaceae) grains, such as peas and beans, are derived from crops that are usually cultivated in the absence of mineral nitrogen fertiliser as these crops can obtain their nitrogen requirement naturally from the air via biological nitrogen fixation. Therefore, pulses present a significantly lower greenhouse gas (GHG) footprint than crops demanding nitrogen fertiliser, whilst also offering significant quantities of starch for the brewing and distilling industries. Mitigation of agriculture derived GHG emissions through utilisation of pulses can have a positive environmental impact. To this end, the potential of exploiting dry, dehulled faba bean (Vicia faba L.) kernel flour as an adjunct for beer production was evaluated. The impact of different temperature regimes and commercial enzymes were assessed for their effect on wort: viscosity; run‐off rate; primary amino nitrogen content and, fermentability. Faba beans demonstrated insufficient endogenous enzyme capacity for starch conversion and generated a viscous wort. However, using a stepped temperature mashing regime and exogenous enzyme additions, the faba bean wort was comparable in processability and fermentability to that of 100% malted barley wort. The faba based beer and co‐product qualities demonstrate the environmental, nutritional and commercial potential of pulses in brewing. © 2020 The Authors. Journal of the Institute of Brewing published by John Wiley & Sons Ltd on behalf of The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

Copyright of Studies about Language / Kalbu Studijos is the property of Studies about Language / Kalbu Studijos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Two types of lager pale beers were produced at industrial scale according to German Beer Purity Law using the same brewing procedure, but different hop varieties. Beer phenols issued from malt and hop can contribute directly to several characteristics of beer, mainly flavor, astringency, haze, body, and fullness. The aim of this paper was to analyze simple phenolic compounds, total polyphenols and total flavonoids contents, antioxidant activity in raw materials (malt and hops) and in samples taken out from several production stages (after wort production, boiling, fermentation, filtering and pasteurisation). Eighteen different phenolic compounds which belong to the groups of hydroxybenzoic and hydroxycinnamic acid derivates, flavan-3-ols, flavonols and procyanidins dimers were analysed. Among all tested phenolic compounds, 9 compounds were identified in malt, 13 in hops, while 10 in samples taken from the brewing process. Based on the obtained results, it is suggested that the choice of hops is very important for obtaining the desired beer quality and to establish its shelf life. [ABSTRACT FROM AUTHOR]

Introduction. The prospects of using buckwheat and buckwheat malt for the production of low-gluten beer are shown. Materials and methods. Beer wort and beer were made from crushed white buckwheat and buckwheat malt in the ratio of 85, 90, 95 percent barley malt and 15, 10, 5 percent (crushed buckwheat and buckwheat malt). To determine the content of amine nitrogen iodometric method was used, to determine the content of reducing substances the method of Wilshteter-Schudl was used, the protein content was determined by the method of Keldal, the starch content was determined by the method of Evers. Results and discussion. Gluten is absent in such cereals as buckwheat and rice, and in other cereals the amount of gluten is: corn 80 ppm, barley 151 ppm, wheat 162 ppm. Therefore, for the preparation of low-gluten beer, crushed white buckwheat, buckwheat malt and barley malt are recommended. The sample with the replacement of 5% barley malt on buckwheat has the highest content of reducing substances, namely 91.0 g per 100 g of extract and amine nitrogen 167.1 mg per 100 g of extract, the content of ethyl alcohol in the finished beer 3.5% by weight at mass fraction of the actual extract of 4.83% by mass. When replacing barley malt with crushed white buckwheat, it was better to replace it with 5% barley malt. The content of reducing substances was 86.9 g per 100 g of extract, and the content of amine nitrogen was 154.9 mg per 100 g of extract. The obtained beer of this sample has the best result in terms of alcohol content of 2.9% by weight and in terms of mass fraction of real extract - 5.53% by weight. As the amount of crushed buckwheat and buckwheat malt increases, the amount of reducing substances and amine nitrogen decreases due to the insufficient amount of hydrolytic enzymes in barley malt, under the action of which the above substances are formed. Thus, in the sample with the replacement of 5% barley malt by buckwheat, the content of reducing substances was 92 g per 100 g of extract, and the content of amine nitrogen was 168 mg per 100 g of extract. Whereas in the sample with a substitution of 15% barley malt, these figures are 82 g per 100 g of extract and 91 g per 100 g of extract, respectively. Conclusions. The best crop for the production of low-gluten beer is crushed white buckwheat and buckwheat malt in a ratio of 95:5. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the effect of yeast generations on fermentation and maturation processes, the content of volatile compounds of beer and viability and vitality of yeast biomass on an industrial scale. The experiments with fermentation and maturation were performed in fermentation tanks. The wort was aerated with sterile air. Yeast (S. pastorianus) bottom fermentation was used in fermentation. For pitching four generations (passages) of yeast were used as follows: 1st, 2nd, 3rd and 4th generation. The processes of fermentation and maturation were carried out in the same technological conditions (temperature and pressure). During fermentation and maturation, the changes in the content of the extract, yeast growth and vitality and selected volatile compounds like esters, alcohols and carbonyl compounds were investigated. With the increase in the number of yeast generations, especially from the 2nd generation used in the fermentation process, the content of acetaldehyde and esters increased. Despite the slight differences between generations, the changes are statistically significant. The content of diacetyl is stable for the 1st, 2nd and 3rd generation and higher for the 4th generation. Diversified yeast generations used in the process of fermentation did not affect significantly the final quality of beer. [ABSTRACT FROM AUTHOR]

This study aimed to model the inactivation of Lactobacillus brevis DSM 6235 while retaining the viability of yeasts during washing brewer's yeast with phosphoric acid and chlorine dioxide. The independent variables in the acid washing were pH (1–3) and temperature (1–9 °C), whereas in the washing with chlorine dioxide, concentration (10–90 mg/L) and temperature (5–25 °C) were assessed. The predictive models obtained for the four response variables γLA, γCl (decimal reduction of L. brevis DSM 6235), Vf/V0LA, and Vf/V0Cl (brewer's yeast viability ratio) were found to have R2 > 0.80 and values of Fcalc > Freference. Then, the models were considered predictive and statistically significant (p < 0.10). Our results indicated that phosphoric acid and chlorine dioxide washing resulted in up to 7 and 6.4 (log CFU/mL) decimal reductions of L. brevis DSM 6235, respectively. On the other hand, the viability of the brewer's yeast ranged from 22.3 to 99.4%. L. brevis DSM 6235 inactivation was significantly influenced by parameters pH(Q) and T°C(Q) when phosphoric acid was applied, and by parameters mg/L(L), mg/L(Q), T°C(Q), and mg/L × T°C when ClO2 was applied. The validation of the models resulted in bias (γLA, 0.93/Vf/V0LA, 0.99 – γCl, 1.0/Vf/V0Cl, 0.99) and accuracy values (γLA, 1.12/Vf/V0LA, 1.01 – γCl, 1.08/Vf/V0Cl, 1.03). The results of this study indicate that it might be possible to decontaminate brewer's yeast through acid and chlorine dioxide washing while keeping its viability. This procedure will result in the reduction of costs and the lower generation of brewer's waste. [ABSTRACT FROM AUTHOR]

Introduction. The aim of the study was to study the bitter substances of hops to establish the dependence of the bitterness of the wort and the quality of beer hops on the quantitative and qualitative composition of alpha-acids hop homologues, in particular, on the content of cohumulone in alpha-acids. Materials and methods. Aromatic and bitter hops with different content of cohumulone in the composition of alpha-acids and beer made from it were studied. High-performance liquid chromatography was used to determine the amount and composition of hop bitter substances and products of their transformation in the brewing process as well as spectrophotometric methods of quality control of the bitterness of hopped wort and finished beer. Results and discussion. It is noted that alpha-acids of the studied varieties contain a wide range of cohumulone content: from 19.6% in hops of Alta variety to 43.8% in hops of Ruslan variety. Establishing the relationship between the quantity and quality of bitter substances of hops and the bitterness and quality of hopped wort and beer show that with increasing mass fraction of cohumulone in the composition of alpha-acids of aromatic hops by 1% with a ratio of beta-acids to alpha-acids of 1.11-1.34 the value of bitterness of the wort hopped by them increases from 0.69% for Gaidamats'kyi variety to 1.05% for Slovyanka variety. In bitter hops, the ratio of beta-acids to alpha-acids is much lower and is 0.51-0.74. Analysis of the relationship between the growth of cohumulone and the change in the bitterness of the wort hopped with bitter varieties shows that with increasing the share of cohumulone in the alpha-acids of bitter hops by 1% the bitterness of hop wort increases from 0.19% for Ruslan to 0.38% for the variety Promin'. Between the bitterness of the wort and the amount of cohumulone with hops when using both bitter and aromatic varieties, there is a strong relationship as evidenced by the correlation coefficient which is for bitter varieties r = 0.90±0.10, for aromatic r = 0.98 ± 0.20. In the formation of the bitterness of the wort, hopped with aromatic varieties from the ratio of beta-acids to alpha-acids is more than one, the role of beta-acid compounds is much higher compared to bitter varieties. Conclusions. When used for hop wort of bitter type hops with different composition of alpha-acids, their use is more effective in varieties with a high content of cohumulone. [ABSTRACT FROM AUTHOR]

Beer is a complex product, which can use a large diversity of matters as adjuncts. Beet peels (BP) is as a food waste generated from restaurant kitchens/industries. This study investigated the effect of BP as a brewing adjunct on volatile/phenolic compounds, and antioxidant properties of Beer. Worts supplemented with BP were produced using 4 treatments (including a control, B1, B2, and B3). Fermentations were conducted for 11 days at 18 °C, aged for 15 days at 3 °C, and bottled using 7 g of sucrose per bottle. Then maturated for 15 days at 20 °C. Samples were analysed using HPLC (non-volatile compounds), GC-MS (volatile compounds), and antioxidant activity. Increasing the amount of BP during wort preparation revealed a significant increase of volatile profile, phenolic composition, and antioxidant activity. In contrast, was observed a significant decrease in glycerol content. Finally, B2 contained a higher content of acetate esters, hydroxybenzoic/hydroxycinnamic acids and antioxidant activity. • A novel use for beet peels (BP) waste was explored. • BP enhanced wort and beer's antioxidant activity. • Ethanol, glycerol, and organic acids were influenced by BP. • Yeast viability was impacted by BP supplementation. • BP supplementation altered beer volatile and phenolic profiles. [ABSTRACT FROM AUTHOR]

The aim of this study was to use unconventional malts in beer production and observe their effect on the wort viscosity. Six malts were analysed in this study—barley, black barley, oat, wheat, rye, and corn. Firstly, the parameters of cereals were measured after the malting process in an experimental malting house and wort production. Samples were analysed in each phase of the mashing process. Carbohydrate contents and viscosities were analytically determined from the samples. The resulting values of the dynamic viscosity were significantly higher than the values obtained by other authors, ranging from 3.4 up to 35.5 mPa·s−1. This study also confirmed the hypothesis that states that the breakdown of carbohydrates leads to a decrease in viscosity. Values measured in the black barley malt sample were higher when compared with light barley malt. Unconventional malts had a higher viscosity and were thus more difficult to filter. If these types of malts are used it is recommended to add barley malts or malts with a higher enzyme activity to them.

In addition to ethanol yield, the production of flavour congeners during fermentation is a major consideration for Scotch whisky producers. Experimental whisky fermentations can provide useful information to the industry, and this is the focus of this paper. This study investigated the impact of wort pretreatments (boiled, autoclaved, filtered) on fermentation performance and flavour development in Scotch whisky distillates as an alternative to freezing wort for storage. Our study showed that no significant sensorial differences were detected in low wines (first distillates), while the chemical compositions showed clear changes in increased levels of esters and higher alcohols in boiled and autoclaved wort. In contrast, filtered wort comprised overall lower levels of congeners. Regarding alcohol yield, all three pretreatments resulted in decreased yields. In practice, the pretreatment of wort prior to fermentation requires additional process operations, while freezing requires large storage units. The pretreatments adopted in this study significantly influence the composition of the malt wort used for experimental whisky fermentations, and this results in a poorer fermentation performance compared with untreated wort. We recommend the use of fresh or frozen wort as the best options for small-scale fermentation trials.

It is established that the introduced Anchellotte grape variety corresponds to the requirements of GOST 32030-2013 by organoleptic and physicochemical parameters. The qualitative indicators of wort and wine material from Anchellotte variety are determined in comparison with the control Saperavi variety. Tasting assessment confirmed the viability of the Anchellotte grape variety as a raw material for the production of quality red wines.

The results of biochemical activity of lactose fermenting yeasts in the wort based on whey, obtained by thermo acid coagulation of milk by berry raw material (sterilized black currant paste) are shown. The extraction of black currant’ valuable components occur in the protein foundation and colored whey, which can be used in the production of fermented beverages with high biological and nutrition value. It was found from the analysis of lactose fermenting yeasts’ biomass accommodation that the biggest growth of yeasts in the wort based on colored whey was in the samples which are fermented by Zygosaccharomyces lactis 868-K – the general amount of cells was (78.1...79.9)∙106 CFU/ml for 48 hours. The optimal fermentation temperature (30…32 °C) was established by the parameters of fermentation activity: accumulation of ethyl alcohol and carbon dioxide in the wort, the total amount of yeasts cells.The obtained results were used in the technology development of non-alcocholic beverages based on colored whey.

The current market of low-alcohol beverages has been evaluated. The production of alcohol-free beverages is characterized by an extremely wide variety of raw materials. It is allowed to use juices, concentrates, infusions, and extracts of vegetable raw materials, flavours, emulsions, aromatic bases, food acids, vitamins, colourants, stabilizers, preservatives, clarifiers, opacifiers, sweeteners, and other raw materials that meet the requirements of regulations in effect and are authorized by the Ministry of Health. It has been established that the use of natural vegetable raw materials, which are a source of biologically active substances, will help increase the demand for these beverages. As such raw material, it has been suggested to use sugar sorghum, which is a promising agricultural crop and is characterized by a rich component composition. It has been suggested to obtain low-alcohol beverages by wort fermentationon on the basis of sugar sorghum juice, with the addition of apple and apple-cherry concentrates. The physicochemical parameters of the wort have been determined, and suggested the modes of its fermentation with dry yeast from the manufacturers Biowin (Brewgo-01) and Fermivin (Gervin GV1), related to brewing and wine yeast races, respectively. The influence of these yeasts on the accumulation of fermentation by-products and on the formation of organoleptic characteristics of beverages has been investigated. It has been found that in the samples studied, most of the fermentation by-products are in quantities close to the perception threshold, and, certainly, they affect the taste and aroma profile of the finished beverages. The profile charts of taste and aroma have been constructed, and the conclusion has been drawn about the prospects of using sugar sorghum juice in the low-alcohol beverages technology based on natural raw materials.

Approximately 25% of all carbohydrates in industrial worts are poorly, if at all, fermented by brewing yeast. This includes dextrins, β-glucans, arabinose, xylose, disaccharides such as isomaltose, nigerose, kojibiose, and trisaccharides such as panose and isopanose. As the efficient utilization of carbohydrates during the wort’s fermentation impacts the alcohol yield and the organoleptic traits of the product, developing brewing strains with enhanced abilities to ferment subsets of these sugars is highly desirable. In this study, we developed Saccharomyces pastorianus laboratory yeast strains with a superior capacity to grow on isomaltose and panose. First, we designed a plasmid toolbox for the stable integration of genes into lager strains. Next, we used the toolbox to elevate the levels of the α-glucoside transporter Agt1 and the major isomaltase Ima1. This was achieved by integrating synthetic AGT1 and IMA1 genes under the control of strong constitutive promoters into defined genomic sites. As a result, strains carrying both genes showed a superior capacity to grow on panose and isomaltose, indicating that Ima1 and Agt1 act in synergy to consume these sugars. Our study suggests that non-GMO strategies aiming to develop strains with improved isomaltose and panose utilization could include identifying strains that overexpress AGT1 and IMA1.

The phenolic compounds in beer mostly originate from barley malt, whereas minority is derived from hops. The content of phenolic compounds in the final product depends on the quality and quantity of raw materials and production process. Phenolic compounds have a decisive influence on the physical and sensory stability of beer. At the same time, their sufficient intake, taking into account moderate alcohol consumption, is associated with the prevention of chronic diseases. Researches of recent years are focused mainly on protein - polyphenol interactions, but potential of phenolic compounds as antioxidants shifted interest toward preserving these compounds from the raw materials to the final beer. In general, their content is found to increase significantly during malting and mashing, but decrease markedly during the subsequent fermentation and storage. By selecting the appropriate raw materials and adequate control of technological parameters, the conditions for the release and retention of phenolic antioxidants can be optimized. However, further researches are needed to provide a clear insight into the fate of phenolic compounds during beer production. [ABSTRACT FROM AUTHOR]

Copyright of Revista Facultad de Ingeniería - UPTC is the property of Universidad Pedagogica y Tecnologica de Colombia, Facultad de Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper aimed to investigate the influence of certain wheat and wheat malt quality indicators on limit of attenuation of wort (LAT). The experiment was conducted using wheats that have been proven to display the best malting properties with heightened total and soluble N and very good viscosity. Standard micromalting and brewing processes and analysis were applied. The obtained results showed that the quality of analyzed malts was satisfying. Statistical analysis determined no significant correlation between the limit of attenuation of wort and any of the other analyzed quality indicators. The lack of close correlations between indicators is probably due to the extremely complex intertwine of factors influencing the LAT, pointing to the fact that this particular indicator should be observed as separate and mainly variety-dependent. [ABSTRACT FROM AUTHOR]

The partial substitution of barley malt has been one of the main strategies of breweries to reduce production costs. In Brazil, as in other countries, maize is a raw material that is used mostly for this purpose. Aiming for strategic cost management, some large breweries have adopted a reduction in the time and energy costs of the process. As an example, changes have been made to the traditional mashing curves by reducing the times or omitting the proteolytic step. The objective of this work was to compare the physical and chemical aspects of sweet and bitter worts prepared through experimental design with and without the addition of maize as adjunct, as well as the execution or not of the proteolytic step in mashing. Color, total acidity, extract, total reducing sugars, total phenolic compounds, and proteins content were evaluated. In addition, the antioxidant activity was determined. The wort obtained with maize and not submitted to the proteolytic step presented a bright color as well as reduced phenolic compounds, protein, and antioxidant activity. Comparatively, the action of proteases in the wort resulted in a greater release of total reducing sugars, a more intense color, and a higher content of total nitrogen and phenolic compounds. The results indicate that despite being an alternative to reduce costs in the brewing process, the use of the adjunct and the exclusion of the proteolytic step of mashing will imply a poor wort in regards to nutrition, which can compromise the activity of the yeast during the process and therefore affect the quality of the final product. [ABSTRACT FROM AUTHOR]

Der Sachunterricht setzt sich zusammen aus allen Bereichen der natur- und gesellschaftswissenschaftlichen Fächer sowie dem Fach Erdkunde. Daher werden im Unterricht oft komplexe Themen behandelt, die nicht nur die Wahrnehmung der Kinder auf die Umwelt erweitern, sondern auch neue Wörter erfordern, um angemessen über diese neuen Inhalte sprechen zu können. Der Erwerb von neuem Fachvokabular knüpft dabei an den bisherigen Wortschatzerwerb an. Beim Erwerb neuer Wörter leisten Kinder sehr viel: Neue Wörter müssen nicht nur phonologisch (lautlich) und semantisch (inhaltlich) im Langzeitgedächtnis abgespeichert werden. Wörter können dabei in vielfältigen Beziehungen zueinanderstehen (Teile eines Ganzen, Unterkategorien ...). Auch diese Informationen gehören zu einem neuen „Lexikoneintrag“ dazu, denn unser Gehirn nutzt diese vielfältigen Strukturen, um Wörter in unserem mentalen Lexikon abzuspeichern. Eine gezielte Wortschatzarbeit im Rahmen des sprachsensiblen Unterrichts kann sich dies zu Nutze machen. Dabei ist es wichtig anzumerken, dass sprachsensibler Unterricht allen Schülern zu Gute kommt. Vor allem aber Kindern mit Migrationshintergrund oder Kindern aus bildungsfernen Elternhäusern, die im Unterricht häufig durch zu komplexe Sprache von der Bildungsteilhabe abgekoppelt werden, profitieren davon. Sprachliche Schwierigkeiten sind ein großer Faktor für Bildungsungleichheit. Im vorliegenden Artikel geht es um die Erarbeitung des Fachwortschatzes zum Thema „Fahrradteile“. Zu diesem Thema habe ich einen Wortspeicher erstellt, dessen sprachliche und fachdidaktische Hintergründe ich darlegen werde. Außerdem werde ich Vorschläge zum sinnvollen Einsatz des Wortspeichers im Unterricht machen. Im Fazit soll es darum gehen, inwiefern meine Schülerinnen und Schüler im Anschluss an die Wortschatzarbeit in der Lage waren, das neu erworbene Fachvokabular selbstständig anzuwenden. [ABSTRACT FROM AUTHOR]

Adjuncts like rice, wheat and sorghum are used by beer manufacturers worldwide to reduce the cost of production by replacing malt as a starch source. Rice is the most widely used adjunct in Asian countries. Understanding the enzyme kinetics in mashing process is vitally important to maximize sugar yield at a minimum cost. In this research, a semi-empirical model was developed for the mashing process, based on enzyme kinetic equations and experimental results; and this model was used to optimize the operating conditions when enzymes are not added externally. As predicted by the model, when 30% (w/w) of rice was used as an adjunct the maximum sugar yield can be obtained at 56° C and 6.5 pH, and the optimum temperature for mashing process increases with acidity. Since the acidity of solution increases during the mashing process due to the formation of organic acids, use of an increasing temperature profile is recommended to get the maximum output from the mashing process. [ABSTRACT FROM AUTHOR]

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In brewing industry, adjuncts may replace malt, but they may also represent a raw material for brewing beer demonstrating different, specific organoleptic qualities. Triticale grain may give good quality malts, characterised by high extraction capacity, high diastatic power and short saccharification time. The purpose of the research was to determine the impact of triticale malt application on physiochemical composition and profile of volatile compounds in beer. In fermented wort, the content of ethyl alcohol, extract, sugars, general acidity, colour, haze, free aminonitrogen and volatile compound profile (GC-SPME) was determined. Beers produced from the triticale malt or with use of a malt mixture were characterised by higher acidity and lower ethyl acetate butanol and isoamyl alcohol. The worts analysed in the process demonstrated parameters normative for pale malts. The triticale malt may be an alternative for barley malt. [ABSTRACT FROM AUTHOR]

The current market of low-alcohol beverages has been evaluated. The production of alcohol-free beverages is characterized by an extremely wide variety of raw materials. It is allowed to use juices, concentrates, infusions, and extracts of vegetable raw materials, flavours, emulsions, aromatic bases, food acids, vitamins, colourants, stabilizers, preservatives, clarifiers, opacifiers, sweeteners, and other raw materials that meet the requirements of regulations in effect and are authorized by the Ministry of Health. It has been established that the use of natural vegetable raw materials, which are a source of biologically active substances, will help increase the demand for these beverages. As such raw material, it has been suggested to use sugar sorghum, which is a promising agricultural crop and is characterized by a rich component composition. It has been suggested to obtain low-alcohol beverages by wort fermentationon on the basis of sugar sorghum juice, with the addition of apple and apple-cherry concentrates. The physicochemical parameters of the wort have been determined, and suggested the modes of its fermentation with dry yeast from the manufacturers Biowin (Brewgo-01) and Fermivin (Gervin GV1), related to brewing and wine yeast races, respectively. The influence of these yeasts on the accumulation of fermentation by-products and on the formation of organoleptic characteristics of beverages has been investigated. It has been found that in the samples studied, most of the fermentation by-products are in quantities close to the perception threshold, and, certainly, they affect the taste and aroma profile of the finished beverages. The profile charts of taste and aroma have been constructed, and the conclusion has been drawn about the prospects of using sugar sorghum juice in the low-alcohol beverages technology based on natural raw materials. [ABSTRACT FROM AUTHOR]

Introduction. It has been determined the influence of drinking running water purified by clinoptilolite, rock crystal and activated charcoal on the vitamin content of wort and kvass. Materials and methods. The kvass made by kvass rye wort fermentation with the help of yeast Saccharomyces cerevisiae MP-10 was analyzed. The dry matter content was determined by the areometric method, the content of vitamins by the ability of test-cultures to grow in the presence of certain vitamins. Thiamine and riboflavin were determined by fluorometric method. Results and discussion. In the purified water, the total iron content was 0,01 mg/dm3, the total water hardness was 1,1 mmol/dm3, the permanganate oxidation was 0,5 mg O2/dm3. The fermentation process was similar to both samples. While the total duration of fermentation of the experimental sample was 13% less, that is due to a decrease in the number of vitamins in the initial wort. The water mineral composition significantly influenced on the content of vitamins in the initial and fermented wort and kvass, in particular, the amount of thiamine and riboflavin in the prototype increased at an average 2.5 times, and the folic acid content at 5 times, that can be explained by the formation in the control sample of water insoluble complexes with bivalent metals. At using model solutions with an index of total water hardness of 5 mmol/dm3, the thiamine content in the fermented wort decreased by 6,7 times compared to the wort with demineralized water. To ensure high levels of vitamins in the kvass, in particular thiamine, riboflavin and folic acid, process water should have a total hardness no more than 1 mmol/dm3 and contain no iron ions. Conclusions. The use of purified water provides the increase in the content of vitamins in the kvass and getting the product with their correlation physiologically acceptable to the human body. [ABSTRACT FROM AUTHOR]

The role of nitrogenous components in malt and wort during the production of beer has long been recognized. The concentration and range of wort amino acids impact on ethanolic fermentation by yeast and on the production of a range of flavour and aroma compounds in the final beer. This review summarizes research on Free Amino Nitrogen (FAN) within brewing, including various methods of analysis. [ABSTRACT FROM AUTHOR]

Crushing and enzyme treatment are pivotal factors that cannot be ignored in the mashing stage of qingke (hull-less barley) craft beer brewing. This study aimed to explore the impact of different mashing conditions on physicochemical, fermentation, and antioxidant properties of qingke wort as well as elucidate the mechanisms of mashing conditions affecting the quality of qingke wort. The results showed that wort with a high fermentable sugar content, including maltose and glucose, could be obtained using a crushed size smaller than 0.9 mm. Furthermore, enzyme treatment further led to an increase in fermentable sugar content, enhancing the fermentation capacity of qingke wort. Notably, crushing significantly affected the antioxidant properties of qingke wort, with smaller crushed particle sizes yielded superior antioxidant properties to the wort, mainly due to the increase in the content of phenolic compounds such as chlorogenic acid, caffeic acid, and epicatechin. • Qingke malt with a crushed size of less than 0.9 mm is suitable for beer brewing. • Phenolic compounds are the main antioxidants in qingke wort. • Crushing and enzyme treatment can effectively improve the quality of qingke wort. [ABSTRACT FROM AUTHOR]

This research explores feasibility of adsorption method used for regulating polypenols content in wort with a view of improving beer quality. It examines adsorption of polyphenols (quercetin, gallic acid, rutin) from pure substance solutions, their mixtures and beer wort treated by sorbents that differ by origin, making, structure and surface chemical composition. The work determines patterns and specific features of polyphenols adsorption with activated carbons. To describe adsorption mechanism more precisely, we specified structure, surface chemical condition, and calculated adsorption parameters using equations of Langmuir, Freundlich and Dubinin-Radushkevich, and the multilayer adsorption theory (BET model). It is demonstrated that polyphenols adsorption mechanism depends on carbon characteristics and is of physical nature that reveals itself in dispersion interaction in micropores and in specific one with oxygen-containing functional group (OFG) on carbon surface. Polyphenol competitive adsorption in mixture and wort recognized. At polyphenols adsorption from model solutions and wort, carbon sorbents are identified to share sufficiently close sorption characteristics. We performed comparative evaluation of quality characteristics of beer produced from activated carbons treated and untreated worts. It is shown that beer samples produced from unhopped wort filtered through semi-coke adsorption, meet regulatory standards requirements of safety by organoleptic, physical and chemical indicators. Moreover, beer obtained from semi-coke treated wort exceeds control sample in terms of organoleptic and stability ensuring indicators.

This paper presents the results of wort dynamic viscosity and activation energy during fermentation. The effect of temperature and storing time on both parameters was investigated. Measurements were performed on two wort samples. The first sample was taken at the beginning of fermentation, and the second sample after three hours of fermentation. Both samples were also measured after three weeks of storing. Dynamic viscosity measurements were performed with a digital rotational viscometer Anton Paar DV-3P, the principle of which is based on the dependency of sample resistance to probe rotation. Results of measurements are shown as graphical dependencies of both analysed parameters on temperature. The temperature dependence of dynamic viscosity can be characterised by a decreasing exponential function, while in case of activation energy linear increasing characters were obtained. Longer fermentation and storing period caused a decrease in both analysed parameters, due to the structural changes in wort samples during fermentation and storing.

The aim of this study was to assess the possibility of shaping properties of beers at the stage of brewing wort production with the use of various types of special malts (chocolate pale, chocolate dark, wheat chocolate, brown barley) and roasted barley grains. The carbohydrate profile, polyphenols content, antioxidant capacity, 5-hydroxymethylfurfural content, and the browning index level were analyzed. Statistical analysis showed significant differences in the values of the examined features between the samples. The sugars whose content was most affected by the addition of special malts were maltose and dextrins. The polyphenol content in worts with 10% of additive was 176.02–397.03 mg GAE/L, ferric reducing antioxidant power (FRAP) 1.32–2.07 mmol TE/L, and capacity to reduction radical generated from 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS•+) 1.46–2.70 mmol TE/L. Wort with 40% dark malt showed the highest content of polyphenolic compounds and antioxidant activity (FRAP and ABTS•+). The HMF content and the browning index value were higher for wort with the addition of darker-colored malts (EBC) and increased with increasing dark malt dose.

Growing consumer interest in new beer flavors is contributing to the application of innovative materials and non-Saccharomyces yeast in brewing. The goal of this study was to test the impact of the low lactic acid-producing Lachancea thermotolerans MN477031 strain on the process of fermenting beer wort, with two different concentrations of bitter compounds, and on the quality of the beer produced. Qualify factors were broadly analyzed, including ethanol content, apparent degree of fermentation, sugars, organic acids, free amino nitrogen, glycerol, volatile compounds, ions and so on. It was proven that the L. thermotolerans MN477031 strain demonstrated a high capacity for rapid initiation of wort fermentation, and a tolerance to hop-derived compounds. As a result, the alcohol content in beer from this method of production was approximately 20% lower, while the content of the real extract was significantly higher in comparison to commercial Safbrew T-58. This strain stands out from many strains of L. thermotolerans due to the low lactic acid production and only marginal influence on pH decrease compared to Saccharomyces cerevisiae. Therefore, the potential of MN477031 in the production of different types of beer (not only sour) is very high. The composition of volatile compounds in L. thermotolerans beer differs—not only in terms of the use of the strain, but also in hop variety.

Saccharomyces pastorianus lager brewing yeasts are domesticated hybrids of Saccharomyces cerevisiae and cold-tolerant Saccharomyces eubayanus. To understand the contribution of both parental genomes to maltose metabolism in brewing wort, this study focuses on maltose transport in the S. eubayanus type strain CBS 12357T/FM1318. To obtain complete sequences of the MAL loci of this strain, a near-complete genome assembly was generated using the Oxford Nanopore Technology MinION sequencing platform. Except for CHRXII, all sixteen chromosomes were assembled as single contigs. Four loci harboring putative maltose transporter genes (SeMALT1-4), located in subtelomeric regions of CHRII, CHRV, CHRXIII, and CHRXVI, were completely resolved. The near-identical loci on CHRV and CHRXVI strongly resembled canonical S. cerevisiae MAL loci, while those on CHRII and CHRXIII showed different structures suggestive of gene loss. Overexpression of SeMALT1-4 in a maltose-transport-deficient S. cerevisiae strain restored growth on maltose, but not on maltotriose, indicating maltose-specific transport functionality of all four transporters. Simultaneous CRISPR-Cas9-assisted deletion of only SeMALT2 and SeMALT4, which shared 99.7% sequence identity, eliminated growth of S. eubayanus CBS 12357T on maltose. Transcriptome analysis of S. eubayanus CBS 12357T established that SeMALT1 and SeMALT3, are poorly expressed in maltose-grown cultures, while SeMALT2 and SeMALT4 were expressed at much higher levels than SeMALT1 and SeMALT3, indicating that only SeMALT2/4 are responsible for maltose consumption in CBS 12357T. These results represent a first genomic and physiological characterization of maltose transport in S. eubayanus CBS 12357T and provides a valuable resource for further industrial exploitation of this yeast.