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Mashing is one of the key operations in beer brewing. Together with polyphenolic compounds it can affect the quality and stability of beer. In our pilot brewing trials of pale lager (200 L), malts of three barley varieties were compared using either infusion or double decoction mashing. Total polyphenols, anthocyanogens and flavanoids were determined in sweet and hopped wort. Free phenolics were measured by HPLC coupled with coulometric detection. Antiradical power was determined by RC-DCPI, ARA-DPPH and ESR-T150 methods. In this way the influence of mashing method and barley variety on polyphenols and antiradical activity of sweet wort was demonstrated showing that the effect of mashing was stronger (ANOVA). The results showed significantly higher, i.e. by tens of per cent, levels of all polyphenols studied in both the decoction sweet wort and hopped wort. The decoction process resulted in higher levels of the antiradical power, ARA-DPPH (37-47%) and RC-DCPI (25-60%). A cluster analysis partitioned 28 free phenolic compounds in sweet wort primarily by variety and secondarily by mashing. The Malz malt showed a greater increase in polyphenols, free phenolic compounds and antiradical power in the decoction process compared to the Bojos and Sebastian malts. Decoction mashing introduces higher levels of phenolic antioxidants into the beer with the potential to improve the sensory stability of the beer and provide health benefits to the consumer. The different behaviour of malts and barley varieties needs to be better elucidated in further research. [ABSTRACT FROM AUTHOR]

Due to global competition and consumer demand for innovative products, the brewing industry is exploiting research to create new beer products with complex aromatic profiles. Recently, interest has been focused on non-Saccharomyces yeast strains, employed in the wine sector. In this study, the capability of two Torulaspora delbrueckii strains (T.d. 291 and T.d. Prelude) on metabolizing the basic sugars of wort was investigated and compared with a S. cerevisiae strain (S.c. US-05). More specifically, the consumption of wort sugars (glucose, fructose, maltose, and their mixtures) and the production of ethanol and secondary metabolites were studied, at two fermentation temperatures (20 °C and 13 °C). From the results of the fermentation kinetics, it was concluded that both T. delbrueckii yeasts are able to metabolize all sugars, produce a satisfactory amount of ethanol and grow at either temperature, although with a faster rate at 20 °C. The volatile compounds were significantly affected by the fermentation temperature and the sugar used. Both T. delbrueckii strains demonstrated potential for use in brewing. [ABSTRACT FROM AUTHOR]

In 2007 wort osmolyte concentration (OC) was introduced as a method of measuring malt quality. The OC (molar concentration of solutes) of a mash is predominantly due to the conversion of starch to sugars and storage proteins to smaller nitrogenous compounds. Malt extract (ME) (mass of material in wort) has been used since the 1700's as a measure for malt quality. Here we compare OC and ME to wort sugar concentrations in lines from three U.S. barley breeding programs. Lines were malted using standard protocols. Worts were analyzed for OC with a vapor pressure osmometer, ME by the ASBC Method, and sugars by pulsed amperometric detection of HPLC separated sugars. Correlations between OC and the combined molar concentrations of glucose, maltose, maltotriose, fructose and sucrose (TFS) for lines from breeding programs A, B, and C were (A) r = 0.930, P < 0.0001, (B) r = 0.625, P = 0.0014, and C) r = 0.667, P < 0.0001. Correlations between ME and TFS were (A) r = 0.408, P = 0.850, (B) r = 0.646, P = 0.0009, and (C) r = 0.081, P = 0.650. Correlations between OC and wort maltose were (A) r = 0.904, P= <0.0001, (B) r = 0.262, P = 0.2279, and (C) r = 0.105, P = 0.5534. Correlations between ME and wort maltose lines were (A) r = 0.009, P = 0.966, (B) r = 0.272, P = 0.2094, and (C) r= −0.011, P = 0.9504. This study indicates that OC is far superior to ME in the prediction of fermentable sugars in wort for some breeders' lines and about equal to ME for others. These data also indicate that those lines that correlated well with fermentable sugars also correlated well with sucrose. [ABSTRACT FROM AUTHOR]

This study evaluated the components that contribute to the International Bitterness Unit (IBU) of wort and beer. A range of samples were analyzed in this study, including beer with 47.5 IBU containing 39.9 ppm iso-α-acid, and one with 49.9 IBU containing only 2.2 ppm iso-alpha acid. The IBU value of wort and beer is mainly contributed by iso-α-acid, non-isomerized α-acid, oxidative polar compounds, and malt-derived polar components. The isomerization of α-acid to iso-α-acid is initiated between 60 °C and 70 °C and the isomerization ratios accelerate rapidly at higher temperature. In the wort boiled below 60 °C, over 50% of the IBU value was contributed by non-isomerized α-acid. Most of the non-isomerized α-acid disappeared during fermentation, whereas the concentration of iso-α-acid was stable. The disappearance of α-acid resulted in a large decrease in the IBU value during fermentation, and the isomerization ratio influenced the degree of the decrease. Over 80% of the IBU value was contributed by the oxidative polar compounds in the beer hopped with the pellet stored at 40 °C for 90 days. Bitterness intensity was less in the beers with deteriorated hops than in those with non-deteriorated hops, despite both having the same IBU values. [ABSTRACT FROM AUTHOR]

Currently, a lot of research is being done on the flavoring compounds of hops. However, much less attention has been paid to the aroma formation considering the hop polyphenol different groups by various methods at the wort hopping stage. Therefore, the main goal of the research is an impact of hopping conditions on the polyphenolic compounds, when the hop is extracted variously into both wort and water to better understand extraction conditions, mechanisms, and factors as well as aroma formation considering various groups of polyphenols. As shown the hop variety, boiling time, and treatment type affect the hop polyphenols amount extracted into the wort. Aromatics varied upon a hop variety and wort boiling time accompanying a positive softening effect regarding aroma formated from malt wort compounds comparing to hopped aqueous extracts. The research proved the most noticeable pH (7 and above) impact on aroma formation caused by the polyphenol conversion. As also shown the first time, a temperature and acidic pH doubled the rutin amount, as well as the best extraction of the prenylflavanoid isoxanthohumol, was achieved by boiling at an alkaline medium pH. The results obtained indicate that various hydrophilic amino acids containing in the wort can stabilize polyphenols affecting the quality indicators of beer produced from different grain raw materials. [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]

The most important success factors of a brewery are to brew a high-standard beer and to sell this product successfully on the market. Especially, guaranteeing an objective product quality is a difficult task, in terms of beer quality, for craft brewers. Following these product stability parameters is not only necessary to secure the expiry date but also with regard to the repeatability of the brews (from batch to batch). To evaluate the precision of a small brew house (1 hL), three different beer types, lager beer (Pilsener), pale ale (Kölsch), and wheat beer (Weißbier) were repeatedly produced and analyzed. It was found that small fluctuations in the wort preparation, in terms of time or analysis, have no noticeable difference on the sensory characteristics of the final product. Nevertheless, strict adherence to the brew recipe and raw material monitoring are necessary in order to keep these deviations as minimal as possible. Finally, this study verified that microbrews can be repeated so that the consumers will not detect any differences with their five senses in the end. [ABSTRACT FROM AUTHOR]

In recent years, Brettanomyces bruxellensis has found increasing application in brewery fermentations. Indeed, B. bruxellensis contributes to the flavour profile of many Belgian beers, typically during secondary or spontaneous fermentation. In North America, the yeast is used in primary fermentation to produce beers with 'Brett' characteristics with 'fruity' and/or 'funky' sensory profiles associated with the production of volatile esters and phenols. However, little is understood about the factors that influence flavour metabolite production or fermentation rate in this yeast. Here, the impact of temperature is reported on fermentation efficiency, flavour metabolite production and carbon utilisation of one commonly used and eight poorly characterised B. bruxellensis strains during wort fermentation. A high degree of strain and temperature‐dependent variability was found in fermentation efficiency and metabolite production amongst B. bruxellensis strains. Further, fermentation efficiency and carbon utilisation were temperature dependent, while ester production increased at higher temperature and phenol production was strain and temperature independent. These results indicate significant strain and temperature dependent variation, suggesting the potential application of strain variability as a tool to achieve product diversity in B. bruxellensis primary fermentations. © 2019 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

Over the last 50 years there has been considerable analytical research on the malt parameters which govern the flavour and aroma, i.e. the 'character', of Scotch malt whisky. This has led to a standard format, the Flavour Wheel, to describe the attributes of any malt spirit and to relate them to a common group of malt parameters. What has not been well documented in the same period are the changes in malt processing technology which have led to a gradual but significant change in the concentrations of reference compounds used in the Flavour Wheel relating to sulphury, nutty/burnt/smoky, peaty and fruity/estery characters. This review covers the most significant of these changes, which have become common practice across the industry, and specifically demonstrates how different malting barley varieties, malt kilning and peating, wort recovery, yeast management, and wash still heating have all contributed to the loss of some styles of malt whisky. © 2019 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

The impact of two commercial enzyme preparations (Mats L Classic, Brewers Compass) used for mashing buckwheat malt was studied to assess their efficacies in releasing D-chiro- and myo-inositols, fermentable sugars and low molecular weight proteins and peptides. Concentrations of these compounds were determined in buckwheat malt, wort, and beer using sensitive ion-exchange and size exclusion chromatography techniques. These were preliminary studies whose general aim was to research the possibilities of functional beer production that could be dedicated for patients with coeliac disease. The application of enzyme preparations had no significant (Brewers Compass) or only little impact (Mats L Classic) on the recovery of D-chiro-inositol (DCI) and myo-inositol (MI) present in the buckwheat malt. In contrast to DCI, whose concentration in the buckwheat beer was 0.3 mg/mL, a minor fraction of MI (11–14.8%) was released into the beverage. In comparison to a barley beer, the oligosaccharide profile of the buckwheat beer was characterized by a relatively high proportion of residual sugars with a degree of polymerization above 5. SEC–HPLC chromatography showed significant changes within the polypeptide fractions after mashing and malting, with a marked increase in the proportion of low molecular weight peptides. [ABSTRACT FROM AUTHOR]

The hop isomerization reaction during the brewing process is interfered by many factors such as wort composition and time resulting in significant bitter substance losses. A novel mash filtration system provides new possibilities, as four wort flows (instead of one) are separated in parallel and thus different wort characteristics are available for enhancing the hop isomerization rate. A laboratory-scale screening experiment was performed to investigate the different effects of the wort parameters beyond the conventional brewhouse range. Based on previous industrial field trials, the boundary parameters (minimum and maximum) of the laboratory-scale wort fractions, corresponding to filter modules 1 and 4, were adjusted accordingly to the pH value (pH 5.6 or 7.0) and original gravity (17.0 or 2.0°P). The parameters boiling time and dosing quantity of α-acids were adapted to conventional brewhouse standards as well as to the novel system. Additionally, the influence of magnesium (0.0 or 40.0 mg/L) dosed to the wort on the isomerization reaction was tested. The results showed that the boiling time at a pH value of 5.6 had more influence on the inversion to iso-α-acids than with a wort pH of 7.0. Even with a high original gravity of 17.0°P, an extension of the boiling time showed no significant effect on the isomerization rate. [ABSTRACT FROM AUTHOR]

Sorghum (Safrari) was valorized into sorghum coffee-lactose stouts using Vernonia amygdalina as a bittering ingredient. These sorghum grains and subsequent sorghum pale malt were tested for their acceptability in the brewing field. Results obtained were the germinative capacity of 99.29 ± 0.58%, a germinative energy of 98.56 ± 1.79%, a thousand corns weight 48.08 ± 0.02 g for the grains, and a diastatic power of 187.44 ± 7.89 WK for sorghum malt. The worts and beers produced were characterized and were found suitable. Moreover, alcohol content in stout beers obtained was between 8.8% and 9.4% ABV. Sensory evaluation was implemented on beers using 30 panellists and the best combination was the one using 50% lactose (250 g) and 50% coffee (250 g) in 5 L of wort during wort boiling. [ABSTRACT FROM AUTHOR]

Abstract Pure Na+ forms of furcellaran (β/κ-hybrid carrageenan), κ-carrageenan, κ/ι-hybrid carrageenan, ι-carrageenan and a hybrid carrageenan mix (made up of κ-, ι-, λ- and ν-carrageenans) were tested as beer wort fining agents. To find out which of the used carrageenans are the best beer wort clarifiers and whether they are prone to overdosage, polysaccharides with varying concentrations and molecular weights were tested. The polysaccharides were characterized by 1H NMR spectroscopy and size-exclusion chromatography. The fining efficiency of the tested polysaccharides was measured nephelometrically. Ultrasonicated and alkali treated carrageenan preparations were tested as beer wort fining agents and compared to the native samples. Undegraded furcellaran, κ-carrageenan and κ/ι-hybrids were efficient in lowering the turbidity of various beer worts, but the addition of ι-carrageenan and the carrageenan mix caused the turbidity to rise above the unfined sample value. Compared to the degraded samples, native galactans were more effective in lowering the beer wort turbidity. Higher concentrations of ultrasonicated carrageenans are needed to clarify the beer wort to similar turbidity values. Alkali treated carrageenans were more efficient beer wort fining agents compared to the native samples. Graphical abstract Image Highlights • Native hybrid carrageenan mix and ι-carrageenan increase the beer wort turbidity. • Native carrageenans are more effective in beer wort fining than degraded samples. • Alkali treatment of carrageenans increases the beer wort clarifying potential. • β/κ-, and κ/ι-hybrid carrageenans are very effective beer wort fining agents. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: This study provides the first detailed investigation into the effect of partially substituting barley malt with quinoa (Chenopodium quinoa Willd.) on the characteristics of wort and beer. Quinoa seeds and flakes were compared in terms of their suitability for brewing. The benefits of applying a commercial enzyme mixture during beer production with quinoa were also investigated. RESULTS: These findings show that quinoa is a good starchy raw material for brewing. Even without exogenous enzymes, it is possible to substitute barley malt with up to 30% quinoa. The form in which quinoa is used has a negligible influence on the quality of the wort and beer. The foam stability of beer made with quinoa was better than that of all‐malt beer, despite there being a lower level of soluble nitrogen in quinoa beer in comparison with all‐malt beer and more than twice the amount of fat in quinoa in comparison to barley malt. CONCLUSION: The addition of unmalted quinoa does not give unpleasant characteristics to the beer and was even found to have a positive effect on its overall sensory quality. This offers brewers an opportunity to develop good beers with new sensory characteristics. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Beer is a fermented drink produced from a wort comprised of barley malt, hops, and water in combination with activity from the yeast strains of the genus Saccharomyces. The beverage is consumed around the world and has a global market controlled by several multinational companies. However, in recent years, it has been possible to note an increase in the number of microbreweries and homebrewers, necessitating additional research both to develop and increase competitiveness of this market sector as well as to improve product quality and promote the reduction of production costs. The process of milling barley malt is often not considered relevant to these goals; however, this operation is influential with regard to, for example, mashing yield, the concentration of polyphenols in beer, and the quality of wort clarification. Therefore, this work evaluates the wet (10%, 20%, 30%, 40%, and 50% moisture content) and dry barley malt milling process as well as analyzes particle size distribution and the mean diameter of particles. The milled grains were submitted to a mashing process to evaluate how particle size contributes to the conversion of starch to sugars and the availability of polyphenols on sweet wort. The results indicate the best milling conditions to obtain a good mashing yield while preserving as much malt husk as possible to facilitate wort clarification. [ABSTRACT FROM AUTHOR]

Determination of the oligosaccharide composition in different wort samples is important to monitor their change during the brewing process with different yeast types. In our work, the concentration of fermentable and non-fermentable sugars were monitored by capillary electrophoresis to observe the effect of two different types of yeasts, Saccharomyces pastorianus and Saccharomycodes ludwigii . The former first ferments the monosaccharides, then the higher sugar oligomers, such as maltose and maltotriose, to ethanol, while the latter fully ferments the monosaccharides, but ferments only very low percentages of the oligosaccharides. Therefore, breweries use Saccharomycodes ludwigii to produce beers with low alcohol content. The CE-LIF traces of the wort samples represented unique oligosaccharide signatures. [ABSTRACT FROM AUTHOR]

Sorghum germination induces the synthesis of a toxigenic hydrogen cyanide (HCN) precursor, dhurrin, and the normal sorghum mashing program is limited in dhurrin removal. Furthermore, the lack of proteases in sorghum malt and the formation of protein aggregate during cooking limit protein hydrolysis. To detoxify the wort, a new mashing program was designed to optimize dhurrin hydrolysis. To improve dhurrin and protein hydrolysis, three strains of lactic acid bacteria were applied for mash acidification. The results show that the degradation of the synthesized dhurrin occurs only in shoots and rootlets when the larger amount of this cyanogenic glucoside is still accumulated in malt seed tissues. Pre-heating the mash to 40 °C prior to decantation significantly reduces dhurrin content of the wort and improves the proteolytic activity. The mash bio-acidification with L. paracasei (ND-34) which removes dhurrin completely in brown wort considerably reduces it to 2.34 ± 0.08 mg/L in white wort and significantly improves protein hydrolysis. [ABSTRACT FROM AUTHOR]

In this paper, an optimal complex is selected of enzyme preparations for hydrolysis of the components of grain raw materials during fermentation of high concentration wort. When selecting enzyme systems, their effect on the technical and chemical parameters of the fermented wash during the fermentation of wort is investigated. For the research, maize grain with a starch content of 69.0% was used. Fermentation was carried out with 18–30% of dry matters (DM) in the wort, using the osmophilic yeast strain Saccharomyces cerevisiae DO-16.The recommended concentration of the enzyme preparation Amylex 4 T (the source of the α-amylase enzyme) – 0.4–0.6 units of α-amylase ability/g of starch – is optimal for the concentration 18– 27% of DS in the wort. For 30% of DS, it is practical to use 0.6 units of α-amylase ability/g of starch. With the use of the enzyme preparation Diazyme TGA (the source of the enzyme glucoamylase), the value is 7.5 units of glucoamylase ability/g of starch, alcohol accumulation in fermented washes was 10.51, 13.35, 15.78% vol., according to the wort concentrations 18, 27, 30%, respectively. It has been established that with the application of the cytolytic enzyme Laminex 750, the concentrations of dissolved carbohydrates and non-dissolved starch have a tendency to decrease. In the samples where the proteolytic enzyme preparation Alphalase AFP was added at a concentration of 0.05 units of proteolytic ability/g of raw materials, there was an increase in the accumulation of yeast cells by 6.5% compared with the reference sample. The recommended concentration of Deltazyme VR XL (the source of β-glucanase and xylanase) is 0.05 units β- glucose/g of raw materials. The addition of a cytolytic and proteolytic enzyme preparation in combination with β-glucanase and xylanase contributed to an increase in the accumulation of ethanol in the washes by 1.7% compared with the reference sample, and to an almost 33% decrease in the concentration of dissolved carbohydrates and non-dissolved starch. On the basis of experimental studies, it has been found that using a complex of enzyme preparations – amylolytic (Amylex 4T), saccharifying (Diazyme TGA), proteolytic (Alphalase AFP), cytolytic (Laminex 750), and complex AF β-glucanase and xylanase (Deltazyme VR XL), in various combinations of their concentrations, – contributed to the intensification of the fermentation process of the wort and increased accumulation of the target product, ethanol, by 0.8–1.4%, depending on the wort concentration. The highest amount of ethanol accumulated at the maximum dosage of additional enzyme preparations. [ABSTRACT FROM AUTHOR]

Wort sugars produced during Congress mashing of pre-Prohibition and modern barley genotypes were compared. Four of five modern cultivars were higher (P < 0.0001) in wort glucose production than six pre-Prohibition cultivars. Mean wort glucose levels of the five modern cultivars were higher (P values from 0.0002 to 0.0021) than that of the pre-Prohibition barleys. In contrast, maltose production was variable and there were no significant differences in mean levels in modern versus pre-Prohibition barley worts, although Manchuria (pre-Prohibition) and Tradition (modern) produced higher (P < 0.0001) levels than other genotypes. Wort maltotriose levels were also quite variable among genotypes, although were higher (P < 0.0001) in Harrington (modern) worts than all others at the end of mashing. By the end of mashing, pre-Prohibition and modern genotypes did not statistically differ in their mean levels of maltotriose (P = 0.514). Glucose equivalents from fermentable sugars (i.e., total glucose from glucose plus hydrolysis of maltose and maltotriose) followed almost an identical pattern as that for maltose. Levels of maltotetraose through maltoheptaose were variable in both pre-Prohibition and modern genotypes throughout mashing. However, these maltodextrins usually decreased rapidly in modern cultivars while they increased or decreased more slowly in pre-Prohibition genotypes. In general, maltotetraose through maltoheptaose were higher (P < 0.0001) in Hanna and Hannchen (pre-Prohibition) worts than in other worts. Sucrose levels were relatively constant during mashing of most pre-Prohibition and modern genotypes. Fructose levels increased throughout mashing for all genotypes. Mean wort fructose levels of modern barley genotypes were significantly higher than those for pre-Prohibition genotypes during most of mashing. [ABSTRACT FROM AUTHOR]

Malted barley contributes directly to wort quality. Wort prepared with malt M1 had a higher free amino nitrogen content, whereas wort prepared with malt M2 had a higher diastatic power. The proteome analysis (pI 3–10) in 2D-PAGE gels showed significant differences, with M1 generating 246 ± 9.8 spots and M2 229 ± 9.8 spots. M1 had more hydrolytic enzymes, in particular an esterase with a size of 43.7 kDa and a p I of 9.4, whereas M2 had more proteins involved in stress tolerance and carbohydrate metabolism, particularly a β-glucosidase with a size of 58.7 kDa and a p I of 7.7, which coincided with its higher diastatic power. The biological activity of M1 showed a band at ca. 150 kDa with high proteolytic activity and another band at 27 kDa with amylase activity. This study is the first report of amylase activity of small molecular size in malts. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effect of Saccharomyces cerevisiae on the formation of gamma-aminobutyric acid (GABA) and the other bioactive amines during wort fermentation. Within 8 days of fermentation, GABA concentration increased to 182.80 and 534.10 mg/L in unspoiled and spoiled worts, respectively. Although formation of tyramine and histamine did not occur in unspoiled wort, 142 mg/L of tyramine and 130 mg/L of histamine were found in spoiled wort at the end of fermentation. Decreased concentrations of tyrosine and histidine were associated with increased concentrations of tyramine and histamine, respectively, in spoiled wort. The results indicated that S. cerevisiae is a causative agent for the accumulation of GABA in wort during fermentation. Therefore, occurrence of GABA in beers should not be considered as one of the indicators of microbial contamination differently from tyramine and histamine. Practical applications Bioactive amines have important metabolic and physiological roles in the body. Their formation in foods is generally related to microorganisms having decarboxylase activity. It was found in this study that spoilage microorganisms produced tyramine and histamine while both spoilage microorganisms and Saccharomyces cerevisiae are responsible for the formation of gamma-aminobutyric acid during unhopped wort fermentation. [ABSTRACT FROM AUTHOR]

During wort boiling, the biochemical and physical reactions in wort give beer its characteristics flavors, color, and bitterness. These reactions are affected by many process factors, such as temperature, boiling time, and concentrations of substances in raw materials. The concentrations of the wort flavor compounds influence not only the quality of wort and finished beer, but also the shelf life. Therefore, it is necessary to control the process parameters as well as the main wort flavor components in wort and beer. Kinetic knowledge provides a basis for the simulation of the boiling process and prediction of the formation and evaporation rate of main wort flavor components. Using the kinetic modelling can achieve a decrease of the boiling time, save energy and produce good beer quality. By comparison with the advanced kinetic studies in chemistry or other food sciences, in brewing science the kinetic investigation remains in its initial stage. This paper summarizes the existing kinetic modelling and kinetic parameters of evaporation and formation of main wort flavor components (e.g., 2-methylbutanal, 3-methylbutanal, DMS, hexanal, 2-phenylethanol, 2-phenylethanal) and the formation and degradation of iso-α-acids. [ABSTRACT FROM AUTHOR]

The impact of carbon dioxide (CO2) supply flow rate on dimethyl sulfide (DMS) removal during wort boiling was studied when applying a 1 h hold between the end of preheating and the beginning of boiling. This was done during wort boiling by varying the boiling power (from 500 to 1,500 W), aiming to reduce energy consumption to reach the target of an end-of-boil DMS concentration of 100 ppb (w/v). When using the Mitani equation, which describes S-methyl methionine (SMM) conversion into DMS and DMS stripping, the preboiling step allowed a reaction rate coefficient of SMM conversion (k1) value of 0.0099 min−1 to be obtained. The values of volatilization rate coefficient of DMS (k2) during the provision of CO2 at a flow rate between 5 and 11 L/min and boiling power between 500 and 1,500 W were between 0.02049 and 0.07882 min−1. It was found that the coefficient k2 increased with the increase of CO2 supply flow rate and the increase of boiling power. At a fixed boiling power of 1,500 W, the use of CO2 supply flow rate permitted the target of 100 ppb to be attained in an interval of 39.21 min for 11 L/min to 62.31 min for 5 L/min. The energy saved in the boiling process when applying CO2 supply flow rate between 5 and 11 L/min was 2.49–4.57 MJ. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the effect of hydrocolloids on the kinetics of ethanol fermentation in high-sugar mead worts. High osmotic pressure, inhibitors and other factors frequently cause sluggish or stuck mead fermentation. In the experiments, natural hydrocolloids – gum arabic, ghatti, karaya, xanthan gum or carob bean gum – were added in an amount of 0.5 g/L to mead worts. During fermentation, the mass of evolved CO 2 was controlled. Anionic hydrocolloids significantly affected the kinetics of mead wort fermentation, significantly accelerating fermentation and causing higher production of ethanol and reduced volatile acidity and acetic acid synthesis by Saccharomyces cerevisiae . Supplementation with gum karaya allowed an increase of ethanol concentration by about 30% compared to control samples. Application of anionic hydrocolloids resulted in significant reduction of amounts of the cations Ca 2+ and Mg 2+ in the solutions, and increased the clarity of young mead. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the effect of the initial beer wort aeration on the process of fermentation, maturation, content of the volatile components of beer and abundance and vitality of yeast biomass. The experiments were performed on an industrial scale, with fermentation and maturation performed in fermentation tanks with a capacity of 3800 hL. The wort was aerated with sterile air in quantities as follows: 7, 10 and 12 mg/L. During fermentation and maturation, the changes in the content of the extract, yeast growth and vitality and more importantly volatile components were investigated. The experiments showed that differentiated aeration has a significant impact on the course of fermentation and metabolic changes. With the increase in wort aeration, the content of acetaldehyde decreased and the concentration of higher alcohols increased. On the other hand, the contents of esters and vicinal diketones did not change. The level of aeration did not affect the final quality of beer. Copyright © 2017 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

Dimethyl sulfide ( DMS), which has a characteristic taste and aroma of cooked celery, is one of the most studied off-flavors in wort and beer. Although there have been many kinetic studies conducted with different wort boiling systems under isothermal conditions, the results are difficult to apply to the heating up process, in which the decomposition of the DMS precursor ( DMS- P), S-methylmethionine ( SMM) also takes place. And it is not easy to define the time of the beginning of wort boiling ( t = 0) under isothermal conditions. In this study, the kinetics of thermal decomposition of SMM was studied using multiple dynamic measurements under non-isothermal conditions. Wort was heated to 140C in sealed test tubes with different heating rates (1-6 K/min). The activation energies ( Ea) and the pre-exponential factors ( A) for the decomposition of SMM were investigated using Coats- Redfern, Kissinger and Flynn- Wall- Ozawa method, respectively. The reaction mechanism follows first-order kinetics. The kinetic triple ( Ea, A, G( α)) obtained from the non-isothermal method is compared with the results from isothermal method. In order to predict the formation of DMS and provide a better control during brewing process, a kinetic model was developed, which is applied to the heating up process and boiling process. Practical Applications The assessment of a wort boiling system and the improvement of a brewing recipe should be based on chemical kinetic perceptions. Dimethylsulfide ( DMS) is a typical leader substance and evaporation factor and also an off-flavor in wort. The knowledge about kinetic analysis on the formation of DMS is one of the important keys in order to control the brewing process and to guarantee the final beer quality. The results in this study can be used to calculate the optimal wort boiling to achieve the desired wort quality and final beer taste under atmospheric boiling conditions. In addition, the results can be used to improve the control of other heating parameters during heating and boiling of the wort. [ABSTRACT FROM AUTHOR]

Fermentation is an essential step in beer brewing: when yeast is added to hopped wort, sugars released from the grain during germination are fermented into ethanol and higher alcohols. To study, simulate and optimise the beer fermentation process, accurate models of the chemical system are required for dynamic simulation of key component concentrations. Since the entire beer production process is a highly complex series of chemical reactions with the presence of over 600 species, many of the specific interactions are not quantitatively understood, a comprehensive dynamic model is impractical. This paper presents a computational implementation of a detailed model describing an industrial beer fermentation process, which is used to simulate published temperature manipulations and compare results with those obtained following the protocol currently in place at WEST Beer brewery (Glasgow, Scotland, UK). A trade-off between design objectives has been identified, making determination of a single optimal scenario challenging. A simulated annealing (SA) algorithm has been developed in order to pursue stochastic optimisation of the fermentor temperature manipulation profile, on the basis of generating an enormous set of plausible manipulations which adhere to suitable operability constraints at an appropriate level of temporal domain discretisation. The objective function considers ethanol maximisation as well as batch time minimisation (with variable weight allocation), and explicit constraints on diacetyl and ethyl acetate concentrations. Promising temperature manipulations have been determined, allowing for batch time reductions of as high as 15 h: this represents a substantial decrease in production cycle time, and is thus expected to improve annual plant throughput and profitability, without any discernible effect on flavour. [ABSTRACT FROM AUTHOR]

Beer is generally considered to be a beverage that has high microbiological stability. However, some undesirable lactic acid bacteria (LAB) can grow in beer and consequently spoil this beverage. In this study, bacteriocin-producing Pediococcus acidilactici K10 was used as a means of bio-acidifying the mash and reducing the spoilage LAB content of the beer. The K10 strain had antimicrobial activity against two beer spoilage LAB strains in wort and did not grow in a beer environment. The K10 strain was inoculated before the mashing step. The effect of K10 as a starter culture was investigated and compared with a control. As a result, filtration time was shortened by 17 min, alcohol content was increased by 137%, foam stability was increased by 156%, bitterness was increased by two bitterness units and there was a significant difference ( p < 0.05) in aromatic and sour odour. The feasibility of using bacteriocin-producing LAB strain in beer brewing is envisaged. Copyright © 2016 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

Low-alcohol beer can be obtained by physical and biological methods. The group of biological methods includes modification of the mashing regimes and changes in the fermentation process. The aim of the present work was to study two mashing regimes for low-alcohol beer production. The increase in the mashing duration at 50 °C led to a linear increase in the extract and the concentration of reducing and fermentable sugars in the wort. It was found that the rate of formation of reducing sugars was higher than that of the formation of fermentable sugars, which can be used for the optimization of the mashing process. The introduction of a pause at 77 °C did not lead to a substantial increase in the concentration of fermentable extract, but did lead to an increase in the total and non-fermentable extract. The available nitrogen content in the laboratory wort was in the range of 120-150 mg/dm3. As a result of conducting fermentation processes with the top-fermenting yeast strain Saccharomyces cerevisiae S-33, it was found that the combination of a small amount of fermentable sugars and a low fermentation temperature led to a beer being obtained that met the requirements for a low-alcohol beverage. Copyright © 2016 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

As wort is the sweet starter liquid for beer, its quality needs to be strictly controlled. It is generally accepted that wort turbidity is of importance in terms of the brewing process and the resulting beer quality. This study investigated the major ingredients of wort turbidity using the malting barley cultivar Dan'er, grown in Jiangsu province, China. It was found that dextrins of low molecular weight constituted the vast majority of the polysaccharides causing wort turbidity. To solve the turbidity problem with the Dan'er malt, the present study supplemented 80 U g−1 of β-amylase, and as an activator, an extra 50 mg L−1 of Ca2+ to the malting process of Dan'er barley. The turbidity of the resulting congress wort of the Dan'er malt declined to <5.0 EBC units, which then met the quality guidelines of the brewery. The results of the present study may also help in developing new turbidity detection methods and yield breeding clues for quality improvement of the barley cultivars in the Jiangsu province of China. Copyright © 2016 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

The current article considers the question of whether vaporescence during wort boiling affects evaporation via the vapour side mass transport. Thereby the vaporization of unwanted flavour components (such as dimethyl sulphide or benzaldehyde) can be influenced negatively or positively, which affects the amount of energy needed. The question is pursued by pre-calculation and experimental validation of the vapour side mass stream at the evaporation surface: for that purpose vaporescence trials were carried out in a plant trial, with both benzaldehyde and water as pure substances and a mixture of benzaldehyde and water in an infinite solution ( xi < 10−6). Trial parameters were process temperature and volume stream of the gas phase. The results obtained by the trials with pure substances enable pre-calculation of vapour side mass transport. Then, pre-calculation is compared with the results of the mixture trials and thus verified. As a result it has to be stated that vaporescence in the brew houses is pre-calculable and that the mass transport has an impact on the vaporescence at the vapour side boundary layer. Copyright © 2016 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

Suggested Abstract: This paper encompasses a re-evaluation of published literature and data regarding wort attenuation in malt distilleries raising questions and discussing how the conventional wisdom has changed over time and what questions still need to be answered. Current knowledge is summarized in the following four points: (a) Under normal malting conditions, starch granules are partially degraded by a combination of α-amylase and α-glucosidase. This complex can open up the granule at specific sites on the surface and create characteristic 'pin-hole' lesions, which may be widened by secondary hydrolysis by α- and β-amylase, limit dextrinase and α-glucosidase (maltase). (b) All of these diastatic enzymes can survive mild kilning, probably by forming heat stable complexes on and within the starch granules and can continue a complete degradation of starch when mashed at ambient temperatures with glucose as the end product. (c) At normal mashing temperatures, starch granules gelatinize and dissolve with a concomitant rapid degradation to glucose, maltose, maltotriose and dextrins ranging from degree of polymerization (DP) 4 to > DP20. If there is immediate wort boiling after run-off, this is the final composition of starch derived carbohydrates according to the conventional paradigm. (d) All malt worts also contain a small amount of panose, isopanose as well as glucosyl maltodextrins, based on a core of 62- α-glucosyl maltose (panose) or 6- α-maltosyl glucose (isopanose), which are remnants of the α-amylase/glucosidase degradation of granular starch. These dextrins are resistant to the action of debranching enzymes and their concentration may vary between 4 and 8% of the malt extract, depending on the degree of modification of the host starch granules. They may be created at the active sites of this enzyme complex when the granule is gelatinized. In a conventional mash of unboiled distilling wort, the spectrum of wort dextrins produced from gelatinized starch is reduced to true 'limit' dextrins of DP4-8 by continued α-amylolysis during early fermentation. These dextrins will contain side chains of either maltose or maltotriose residues surrounding the α-1,6-glucosidic linkage and can be debranched by limit dextrinase during late fermentation, leaving only the above glucosyl maltodextrins dextrins in the spent wash. Copyright © 2016 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

The impact of using different combinations of unmalted barley, Ondea Pro® and barley malt in conjunction with a 35% rice adjunct on mashing performance was examined in a series of small scale mashing trials. The objective was to identify the potential optimal levels and boundaries for the mashing combinations of barley, Ondea Pro®, malt and 35% rice (BOMR) that might apply in commercial brewing. Barley and malt samples used for the trials were selected from a range of Australian commercial barley and malt samples following evaluation by small-scale mashing. This investigation builds on previous studies in order to adapt the technology to brewing styles common in Asia, where the use of high levels of rice adjunct is common. Mashing with the rice adjunct, combined with differing proportions of barley, Ondea Pro® and malt, resulted in higher extract levels than were observed for reference mashing, using either 100% malt reference or 100% barley reference and Ondea Pro® enzymes. Synergistic mashing effects between barley, Ondea Pro® and malt were observed for mash quality and efficiency parameters, particularly wort fermentability. The optimum levels of barley in the grist (with the relative level of Ondea Pro®) were assessed to be in the range 45-55% when paired with 10-20% malt and 35% rice. When the proportion of malt was reduced below 10% of the grist, substantial reductions in wort quality were observed for wort quality parameters including extract, lautering, fermentability, free amino nitrogen and haze. Extension of this new approach to brewing with rice adjuncts will benefit from further research into barley varietal selection in order to better meet brewer's quality requirements for the finished beer. Copyright © 2016 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

The effect of wort filling time on the process of fermentation, maturation, and acetaldehyde content in beer was determined. The experiments were performed on an industrial scale, the fermentation and maturation took place in fermentation tanks. Three tanks were filled using three different intervals. Worts were aerated with sterile air and yeast was added after the second fermentation (third passage). During fermentation and maturation, changes in the content of the apparent extract and the amount of acetaldehyde were investigated. Experiments have shown that different filling times have a significant impact on the course of fermentation and the amount of acetaldehyde. With the increase of wort filling time, fermentation speed improved and acetaldehyde content decreased. [ABSTRACT FROM AUTHOR]

Special malt with high gluten-specific peptidase activity was prepared by germinating barley grain for 8 days at 18 °C and 48 % humidity. Endogenous malt peptidases were characterized and used to degrade gluten in barley wort. Peptidases of aqueous malt extracts degraded celiac-active peptides by cleaving peptide bonds involving proline residues. The peptidase activity was not affected by cultivar, area of cultivation, and high temperatures up to 80 °C during kiln drying. Temperatures up to 50 °C were tolerated without loss of full activity in aqueous solution. The presence of ethanol decreased the activity significantly. Cross-flow filtration, freeze-drying, and evaporation under reduced pressure at 50 °C were used to produce a concentrated enzyme-active malt extract. The latter method yielded the best results, and the obtained concentrate was used to study gluten degradation in barley wort as affected by concentration of the extract, incubation time, and temperature. The gluten content was determined by a competitive R5-ELISA. The addition of 10 % concentrated extract (grist-to-water ratio 1:2.5; 40.4 °Brix) to wort and incubation for 24 h at 50 °C resulted in a gluten-free wort. [ABSTRACT FROM AUTHOR]

Microbial fuel cells (MFC) are bioreactors that are used to generate electricity on the expense of organic substrate oxidation. The MFC's operation-mechanism offers the possibility to use the fuel cell in the beer production technologies to make low or non-alcoholic beers. In this study the effect of MFC anode surface area and riboflavin as an electron shuttle on electric current and on ethanol production in fermentation of wort is demonstrated. The enlargement of anode surface induces an increase of electricity generation (from 4 to 12.5 mA/m²) while the ethanol production decreases. Adding riboflavin to the wort in the MFC results significant increase in electricity production, furthermore it decreases the ethanol synthesis. Addition of 50 µM riboflavin enhances the current output to 51 mA/m² with a 1.5 V/V% decrease of ethanol production, while 100 µM results 86 mA/m² and 2 V/V% decrease of ethanol production. These results show the potentiality to brew low or nonalcoholic beer in MFC. [ABSTRACT FROM AUTHOR]

Methods for mixture particles imaging are increasingly popular in many fields of engineering research. Particularly interesting is application of imaging techniques in the case of mixtures which by their nature take the form of agglomerates inside the flow. There are cases in which introduction of sensors into the flow system is not possible. What is also very often impossible is to perform mixture initial homogenization, required by many measurement apparatuses, due to the fact that such a measurement does not provide reliable information about dispersed phase's morphology. An example of such a case is analysis of the so-called hot trub which is formed during beer wort boiling. Determination of the hot trub amount and knowledge of distribution of its particles' size are the key elements impacting the criteria of optimization of this type of separator's structure. While the sediment particles are traveling towards the bottom the sediment's volumetric share is considerable, which further impedes the analysis of the investigated system. Therefore, in the case of hot trub (which is a mixture with high concentration of dispersed phase), using a non-invasive method based on analysis of digital images is a justified choice. This paper presents an application of the Shadow Sizing method for identification of morphological parameters (diameter) of hot trub particles. Abilities and limitations in detection of hot trub particles traveling within an interrogation cell have been determined. An application of the shadow analysis as a method for determination of dispersed phase's velocity. A way of drawing conclusions from obtained images, later used for PIV analysis with LMS and Adaptive PIV algorithms, has been presented. [ABSTRACT FROM AUTHOR]

Thiamine and riboflavin vitamers are present in a wide range of foods including beer. These vitamers play critical roles in a variety of enzymatic complexes and can promote and maintain metabolism. Currently, the presence and role of these vitamers in the malting and brewing industry have not been widely explored. This research investigated the effects of various fermentation conditions that may lead to the variations in the vitamin content in beer observed by previous researchers. The present research found that during fermentation, the thiamine content of wort is quickly utilized within the first 6 h of a standard fermentation and the uptake of this vitamin is not affected by increases in wort gravity. While no significant changes were observed in extracellular phosphorylated vitamers of thiamine, both free thiamine and thiamine diphosphate accumulated intracellularly during the wort fermentation. Meanwhile extracellular riboflavin vitamers were only poorly utilized during beer fermentations, however flavin mononucleotide rapidly accumulated intracellularly and more so under aerobic conditions. When yeast was exposed to an all-malt high-gravity wort, the thiamine or riboflavin utilization was not affected. However, thiamine utilization was reduced in adjunct-driven high-gravity worts. Notwithstanding the lowered thiamine uptake under high-gravity conditions; there were some minor improvements in fermentation performance and yeast viability. The addition of thiamine to an all-malt wort did appear to enhance yeast viability, both under normal and high-gravity conditions. Copyright © 2016 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

The effect of the buffering capacity of wort on a beer fermentation and the contribution of pH, phosphate, amino acids and organic acids to the buffering capacity of wort were studied. The beer pH depended on the buffering capacity of the corresponding wort and an increase in the buffering capacity of the wort could prolong the time of diacetyl conversion. The higher the wort pH was, the larger the wort buffering capacity. Phosphate was not an effective buffer at the pH of wort. Glutamic acid, aspartic acid and histidine gave weak contributions to the buffering capacity of wort, and the total contribution of these three amino acids was <0.1. Organic acids contributed substantially to the buffering capacity of the wort and the total contribution of organic acids to the buffering capacity of the wort was estimated to be about 0.31. The buffering capacity of lactic acid, citric acid, succinic acid, fumaric acid and pyruvic acid was 30, 50, 77, 15 and 9% of that of acetic acid, respectively, at the same mass concentration. Copyright © 2015 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

The effects of variety and germination time on β-glucan components - total β-glucan (TBG), water insoluble β-glucan (WIBG) and water soluble β-glucan (WSBG) and β-glucanase (BG) levels - before and after malting in improved sorghum varieties SK5912, KSV8 and ICSV400 and their relationships to wort specific viscosity (SV) were studied. This study was part of efforts to aid local malting and brewing industries in the application of sorghum varieties that are abundantly available to reduce costs. At the fifth day of germination, variety ICSV400 had the lowest TBG, WIBG and WSBG levels in its raw and malt samples. Variety SK5912 had the highest TBG, WIBG and WSBG levels in its raw samples, while variety KSV8 had the highest levels of TBG, WIBG and WSBG in its malt samples. Similarly, variety ICSV400 malts developed the highest BG levels, while the KSV8 malts gave the lowest level. The effect of variety, germination time and variety × germination time interaction was significant ( p < 0.05) on the TBG, WIBG and BG levels and was not significant on the WSBG levels. Weak and significant correlation of TBG levels with SV (0.25, p < 0.05 for SK5912; 0.24, p < 0.05 for KSV8; and 0.31, p < 0.05 for ICSV400) was observed in all the samples, suggesting that the low β-glucan levels may not be primarily and solely responsible for any viscosity impediments associated with sorghum worts during run-off. With improvement in the effective utilization of sorghum, ICSV400 appeared the most suitable variety for malting and brewing in Nigeria.Copyright © 2016 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

Decisive to produce a good beer is the production of qualitative wort. The process of wort production requires coordination of operations (temperature / time / pH) in order that from the raw materials used, to handle and to extract the maximum capacity of the production of wort for kg malt. To obtain the optimum potential from malt we should know and interpret very well its parameters. Physical characteristics of malt are very important and affect the technological process of brewing. In this paper are presented the results of physical analyses performed on samples of maltand also is studied the impact of these results in the quality of wort. Each base malt should have mealy contentof 90%. If we will use the infusion method the mealy content must be at least 95%. The bigger are the size of barley grains the higher is their efficiency. The uniformity of malt grains shows how uniform will be its fragmentation. Good malt should have about 90% of its grains uniform in terms of size. Malt is classified by how much percent of its grains are glassy. Therefore it is checked if grains are mealy, half glassy, glassy ends and glassy. If the endosperm is not more than 25% glassy then the malt is called mealy. The malt grains are half glassy if 25-75% of endosperm is glassy. When the endosperm is over 75% glassy the malt is called glassy. Glassy malt produces less extract because the grains are not fragmented as well and hydrolysis occurs with difficulties in mashing process. [ABSTRACT FROM AUTHOR]

The antioxidant activity of brewer’s spent grain (BSG) and malt during different wort elaboration steps, were assessed by employing QUENCHER approach for the DPPH , ABTS + , ORAC, FRAP and Folin–Ciocalteu’s assays. The antioxidant potential of malt and BSG lipophilic fractions, obtained by means of supercritical carbon dioxide extraction (SCE-CO 2 ), and remaining solid residues were evaluated too. The obtained results indicate that in most cases BSG possessed significantly higher radical scavenging capacity, reducing power and total phenolic content as compared to malt prior to wort preparation. SCE-CO 2 yielded 5.49 g of lipophilic fraction per 100 g of BSG, with the activity of 212.36 mg TE/g extract as measured in L-ORAC assay. The SCE-CO 2 reduced the radical scavenging activity and reducing power of BSG by 1–23% in different assays, indicating that considerable part of BSG compounds with particular antioxidant capacity still remains in the solid residue. [ABSTRACT FROM AUTHOR]

Probiotics are considered as significant segments of functional foods. The response surface methodology was used to optimise the fermentation process conditions for the development of a probiotic sorghum wort beverage fermented with Lb. acidophilus LA5. The central composite design was applied with three fermentation parameters such as temperature, inoculation dosage and initial pH. Each parameter was varied at three levels. All parameters had single or interaction significant effects ( P < 0.05) on the response variables. The models were highly significant with very low P -values. The optimum fermentation conditions were as follows: temperature 33 °C, inoculation dosage 0.8 OD600 and pH 5.3. Under these conditions, a probiotic beverage with viable bacterial cell concentration of 8.0 log10 cfu mL−1, final pH 3.7, lactic acid 3.2 g L−1 and total sugar 52.7 g L−1 can be produced. The validation experiments showed a good agreement between the experimental and predicted values. The results showed that sorghum wort is a suitable medium to produce probiotic beverages fermented with Lb. acidophilus LA5. [ABSTRACT FROM AUTHOR]

BACKGROUND Barley wort, an intermediate product of beer brewing, is rich in phenolic compounds. The aim of this work was to evaluate the possibility of increasing the antioxidant content of bread by replacing water with three types of wort: two of them withdrawn at the end of the mashing operation during the production of a Pilsner and a Double Malt Pilsner beer respectively; the other collected at an intermediate stage of mashing of the Pilsner beer. The chemical, physical and sensory properties of the wort-added breads were compared with those of a control bread. RESULTS All three worts led to increased phenolic content, volume and specific volume of the breads and induced significant changes in 11 of 23 sensory descriptors. The highest phenolic contents were detected in breads made either with the Pilsner wort withdrawn at an intermediate stage of mashing or with the Double Malt Pilsner wort. The former also gave the highest increase in volume and specific volume but significantly reduced the scores for crunchiness, firmness and cohesiveness. The latter led to lower increases in volume and specific volume, but less significant changes in the sensory properties were associated with its use. CONCLUSION Worts can be conveniently used to increase the antioxidant content of bread. However, different types of wort can modify to different extents the physical and sensory properties of the product.© 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]