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Copyright of Ingeniería Agrícola y Biosistemas is the property of Universidad Autonoma Chapingo 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.)

Copyright of Research Papers of the Wroclaw University of Economics / Prace Naukowe Uniwersytetu Ekonomicznego we Wroclawiu is the property of Uniwersytet Ekonomiczny we Wroclawiu 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.)

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]

Brewing is a highly complex stepwise process that starts with a mashing step during which starch is gelatinized and converted into oligo- and/or monosaccharides by enzymes and heat. The starch is mostly degraded and utilised during the fermentation process, but grains and hops both contain additional soluble and insoluble complex polysaccharides within their cell walls that persist and can have beneficial or detrimental effects on the brewing process. Previous studies have mostly been restricted to analysing the grain and/or malt prior to entering the brewing process, but here we track the fates of polysaccharides during the entire brewing process. To do this, we utilised a novel approach based on carbohydrate microarray technology. We demonstrate the successful application of this technology to brewing science and show how it can be utilised to obtain an unprecedented level of knowledge about the underlying molecular mechanisms at work. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [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]

During the production of fermented alcoholic beverages, such as wine or beer, the loss of aroma active compounds (AACs) has a significant impact on the overall product aroma. This paper presents the results of an experimental technique in which a condenser was placed on the top of the fermenter in order to reduce such losses. AAC concentrations in beers produced in this way were compared with a control produced without a condenser. There were two main findings: (i) some AACs could be recovered during fermentation and (ii) the technique stimulated the de novo synthesis of esters from carboxylic acids and alcohols. In particular, the production of ethyl esters from the reaction between ethanol and organic acids and the production of acetates from the reaction between acetic acid and alcohols were demonstrated. Consequently, the addition of the condenser changed the final aroma of the beverage. The effect was confirmed by a panel test and AAC quantitation using HS-SPME-GC-MS. The technique could be used by brewers as a tool to modulate the flavor and aroma of beer. [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]

Sulphur compounds present in barley, malt and beer are mostly non-volatile substances (amino acids, proteins, inorganic sulphates) from which volatile sensory active substances can be produced under certain conditions. The presence of these substances in beer can adversely affect its organoleptic properties. Dimethyl sulfi de (DMS) is one of the most studied volatile sulphur compounds in beer; therefore a suitable analytical method for monitoring DMS content is necessary. The static headspace method coupled to gas chromatography with fl ame photometric detector (HS-GC-FPD) used for the determination of DMS content in wort and beer was optimized and validated. Optimal yield of HS extraction was achieved after 30 minutes at 50 °C. DMS contents moved from 9.6 to 59.6 μg.l-1 in the analysed worts, from 6.1 to 34.9 μg.l-1 in beers.

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.

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.

Medicinal plant cultivation in Controlled Environment (CE) is increasing in the context of the new findings concerning the abiotic stress factors manipulation that leads to a significant increment in bioactive substances. Pathogen control is a vital part of the cultivation system, therefore the study was focused on biological methods of controlling a frequently occurring disease, by inoculating the sterile substrates specific in hydroponics, with the beneficial organism. Hypericum perforatum seedlings were inoculated with Fusarium oxysporum and with Trichoderma spp. The results showed that the method of inoculation had a significant effect on the success of the biological control. The plants treated with Trichoderma spp. had a two-fold increase in foliar biomass and better development of roots than the plants inoculated with the pathogen. Morphologically there were no significant differences, with some notable exceptions. The health status of the seedlings inoculated with the pathogen showed signs of the disease, even in the presence of Trichoderma spp. Finally, determinations of Volatile Organic Compounds (VOCs) at the root level showed that the biotic stress was considerable higher in the rockwool substrate that increased the secondary metabolism giving new perspectives in the cultivation of medicinal plants in CEA. [ABSTRACT FROM AUTHOR]

Copyright of Studia Nauk Teologicznych PAN is the property of Polish Academy of Sciences, Committee on Theological Sciences 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.)

Beer manufacturing is one of the most ancient procedures of food manufacturing. The four (in many cases much more) ingredients, the great numbers of technological steps and variations of technological parameters (temperature, time, pressure etc.) have a major influence on both type and quality of the final product. As a result of this, studying beer brewing may offer a great deal of possibilities for numerous researches, scientific examinations, and can provide useful informations for the manufacturing companies as well. At the „Slovak University of Agriculture in Nitra" we examined an entire beer brewing process in October 2013, utilising the Ahlborn sensors, which were integrated in the instruments. Simultaneously, in Gödöllő at the Szent István University, we analysed the effect of malt milling on extract yield and the filterability of wort. We used the brewing parameters (temperature, time, volume ratios), which were experienced in the microbrewery and published in professional literature. Our results verify the conclusions drawn in the professional literature, however they point out the importance of grinding. Results performed on the yields with different grain-constitution might directly be utilised for the specialists of recently in Slovakia and Hungary spreading small-scale, handicraft, and homemade beer brewing.

Acidified wort produced biologically using lactic acid bacteria (LAB) has application during sour beer production and in breweries adhering to the German purity law ( Reinheitsgebot). LAB cultures, however, suffer from end product inhibition and low pH, leading to inefficient lactic acid (LA) yields. Three brewing-relevant LAB ( Pediococcus acidilactici AB39, Lactobacillus amylovorus FST2.11 and Lactobacillus plantarum FST1.7) were examined during batch fermentation of wort possessing increasing buffering capacities (BC). Bacterial growth was progressively impaired when exposed to higher LA concentrations, ceasing in the pH range of 2.9-3.4. The proteolytic rest (50°C) during mashing was found to be a major factor improving the BC of wort. Both a longer mashing profile and the addition of an external protease increased the BC (1.21 and 1.24, respectively) compared with a control wort (1.18), and a positive, linear correlation ( R2 = 0.957) between free amino nitrogen and BC was established. Higher levels of BC led to significant greater LA concentration (up to +24%) after 48 h of fermentation, reaching a maximal value of 11.3 g/L. Even higher LA (maximum 12.8 g/L) could be obtained when external buffers were added to wort, while depletion of micronutrient(s) (monosaccharides, amino acids and/or other unidentified compounds) was suggested as the cause of LAB growth cessation. Overall, a significant improvement in LA production during batch fermentation of wort is possible when BC is improved through mashing and/or inclusion of additives (protease and/or external buffers), with further potential for optimization when strain-dependent nutritional requirements, e.g. sugar and amino acids, are considered. Copyright © 2017 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

Brewer's spent grain (BSG) hydrolysates were used for l-(+)-lactic acid (LA) fermentation by Lactobacillus rhamnosus ATCC 7469. The aim of this study was to evaluate fed-batch LA fermentation of BSG hydrolysate with the addition of glucose, glucose and yeast extract, and wort during LA fermentation and its effect on fermentation parameters such as LA concentration, its volumetric productivity and yield, and L. rhamnosus cell viability. The highest LA yield, volumetric productivity and concentration of 93.3%, 2.0 g/L/h, and 116.1 g/L, respectively, were achieved with glucose and yeast extract addition during fermentation. In fed-batch fermentation with glucose and yeast extract addition significantly higher LA concentration, yield and volumetric productivity (by 194.8; 2.2, and 20.7%, respectively) were achieved compared with batch fermentation. The results indicated that fed-batch fermentation could be used to increase LA fermentation efficiency. Copyright © 2017 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

Beer is the most consumed beverage in the world, especially in countries such as USA, China and Brazil.It is an alcoholic beverage made from malted cereals, and the barley malt is the main ingredient, added with water, hops and yeast. High-pressure processing is a non-traditional method to preserve food and beverages. This technology has become more interesting compared to heat pasteurization, due to the minimal changes it brings to the original nutritional and sensory characteristics of the product, and it comprises two processes: high hydrostatic pressure, which is the most industrially used process, and high-pressure homogenization. The use of high pressure almost does not affect the molecules that are responsible for the aroma and taste, pigments and vitamins compared to the conventional thermal processes. Thus, the products processed by high-pressure processing have similar characteristics compared to fresh products, including beer. The aim of this paper was to review what has been investigated about beer processing using this technology regarding the effects on physicochemical, microbiology and sensory characteristics and related issues. It is organized by processing steps, since high pressure can be applied to malting, mashing, boiling, filtration and pasteurization. Therefore, the beer processed with high-pressure processing may have an extended shelf-life because this process can inactivate beer spoilage microorganisms and result in a superior sensory quality related to freshness and preservation of flavors as it does to juices that are already commercialized. However, beyond this application, high-pressure processing can modify protein structures, such as enzymes that are present in the malt, like α- and β-amylases. This process can activate enzymes to promote, for example, saccharification, or instead inactivate at the end of mashing, depending on the pressure the product is submitted, besides being capable of isomerizing hops to raise beer bitterness. As a consequence, the process may reduce steam demand and residue generation. Therefore, the use of high-pressure processing can potentially replace or be combined with heat processes usually applied to beer, thus bringing benefits to the sensory quality of the product and to the environment. [ABSTRACT FROM AUTHOR]

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 nonalcocholic beverages based on colored whey. [ABSTRACT FROM AUTHOR]

Whilst beers have been produced using various levels of unmalted grains as adjuncts along with malt, brewing with 100 % unmalted grains in combination with added mashing enzymes remains mostly unknown. The aim of this study was to investigate the brewing potential of 100 % unmalted barley, wheat, oat and rye in comparison with 100 % malt. To address this, identical brewing methods were adopted at 10-L scale for each grain type by applying a commercial mashing enzyme blend (Ondea Pro), and selected quality attributes were assessed for respective worts and beers. Different compositions of fermentable wort carbohydrates were observed in the worts (all at ca. 12°P), and in particular oat wort had lower concentration of maltose compared to the others, resulting in the lowest concentration of alcohol in final beer. Moreover, wort made from unmalted grains also showed lower free amino nitrogen and higher viscosity than malt wort. Furthermore, the use of 100 % unmalted grains resulted in a decrease in the levels of colour and brightness, as well as higher alcohols and esters in the final beers. Consequently, the study provides valuable information for exploring beer brewing with 100 % unmalted barley, oat, rye or wheat using exogenously added enzymes. It also helps to understand the process ability by revealing specific needs when manufacturing different type of beers from unmalted grains, potentially paving the way to process optimisation and development of future products. [ABSTRACT FROM AUTHOR]

Inductively coupled plasma mass spectrometry was used for the determination of silicon in beer samples from the Czech market and in brewing raw materials and semiproducts. The content of silicon in barley malt depended on the barley variety and growing region. The goal was to establish silicon concentration in Czech beer and to find out which processes are the most significant in terms of silicon concentration in beer. The silicon concentration in Czech beer ranged from 16 mg/l to 113 mg/l depending especially on two factors. Firstly, the silicon content in beer increased as the original wort concentration and increased secondly, during decoction mashing, silicon from malt was leached to a much greater extent than in the case of infusion mashing.

Adjuncts are also used in beer production to increase beer stability, and possibly to reduce the production costs. Triticale, the first man-made cereal, is the product of a cross between wheat and rye. In this study the possibility of triticale application as the partial substitute for barley malt in wort production was investigated. For wort production two series of experiments were performed in which triticale variety Adonis was used as the substitute for barley malt in grist with and without the addition of commercial enzyme Ultraflo Max. Triticale was added in each of the carried series of experiments as the substitute for malt: 0, 10, 30, 50, and 70% in grist. With the increase in the content of triticale in the grist, viscosity increased. The addition of commercial enzyme Ultraflo Max reduced wort viscosity. The obtained results indicate that worts produced with the addition of triticale variety Adonis in grist had good analytical quality parameters.

The present work aims to study the quality of wort produced using fluoride containing mineral water. The results show that the mineral water has a negative impact on the enzymatic destruction of starch, proteins, color intensity and pH of the wort. The changes of pH during mashing process using tap and mineral water was studied. The lower acidity of wort obtained using mineral water didn’t change during the brewing process. The fluoride content of beer is lower than 5 mg.L-1 when wort is produced using mineral and tap water in 1:1 ratio and citric acid for pH correction. At the same time, the final degree of fermentation, α-amine nitrogen content and the intensity of color of produced wort are close to the control sample. The changes in fluoride ion concentration are monitored using ion-selective potentiometry. The fluoride content is decreased from 5.7 to 4.75 mg.L-1, the most intense change is observed during the mashing process.

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.

The purpose of this work was to examine the influence of the temperature, the pitching rate of yeast and wort composition (Free Amino Nitrogen) on the content of acetaldehyde in beer. It is known, that higher fermentation temperatures stimulate the formation of acetaldehyde, as well as the higher rate of acetaldehyde reduction, leading to lower concentrations in the final beer. Beer produced with increased pitching rate of yeast (26 and 35 × 10[sup]6[/sup] cells•mL[sup]-1[/sup]), contains lower quantities of acetaldehyde as compared to the control beer. Lower content of α-amino nitrogen in result of substitution of 5 to 10�0of the malt with rice, sugar or a combination of both does not lead to considerable differences in the acetaldehyde concentration in beer.

The research was aimed at determining the effect of malting time of grain of selected varieties of brewing barley cultivated in Poland on the quality of Pilsner type malts, with consideration given to their extractivity and natural losses. The experimental material was barley grain of the following varieties: Class, Blask, Riviera, Lailla, Hanka, Sebastian, Bolina, Philadelphia, Tolar, and Stratus. Grain fractions of >2.5 mm were used to produce 4, 5 and 6-day Pilsner type malts under laboratory conditions. The grain, malt and the resultant worts were evaluated and determined for the malting usability acc. to Molina-Cano. Analyses demonstrated that the 4, 5 and 6-day malting of barley grain enabled obtaining malts with functional parameters corresponding to standard values. Elongation of the malting time from 4 to 6 days does not elicit any significant changes in the extractivity of malt, nor in the malting usability of grain, however it increases natural losses of the malted matter.

The objective of this work was to investigate the possibility of triticale application as the partial substitute for malt in wort production. For wort production, two series of experiments were performed in which triticale variety Odyssey, from experimental fields, Rimski Šančevi location (Serbia), was used as the substitute for barley malt in grist with and without the addition of commercial enzyme Ultraflo Max (Novozymes, Denmark). Triticale was added in each of the carried series of experiments as the substitute for malt: 0, 10, 20, 30, 40, 50, 60, 70 and 80% in grist. Experiments were carried out on laboratory scale by the application of infusion procedure for wort production. Regarding extract content, triticale variety Odyssey could be used as the substitute for malt up to 60% without the addition of commercial enzyme Ultraflo Max. With the addition of this enzyme triticale variety Odyssey could be used as a substitute for malt up to 80%, regarding the extract content. With the increase in the content of triticale in the grist, viscosity increased. The addition of commercial enzyme Ultraflo Max significantly reduced wort viscosity. The obtained results indicate that worts produced with the addition of triticale variety Odyssey to grist yielded good analytical quality parameters.

The course of wort fermentation is most often monitored by measuring density by immersion saccharometer or digital densitometer; other methods include classical analysis or automatic analyzers. Another possibility is the measurement of refraction in the course of fermentation. When the original refraction or wort extract is known, refraction unambiguously determines the apparent extract or degree of attenuation. A refractometer with a scale in Brix degrees can be used similarly as a saccharometer having a scale in mass percent of sucrose. In the range of 0-16 mass % sucrose and 0-8% ethanol refraction is a linear function of concentration; this allows us to calculate concentration of ethanol, real extract and also an apparent extract in the course of fermentation from the values of actual and original refraction. Examples are given of measurement and instrument calibration. The measurements can be done with simple and inexpensive refractometers with computing compensation of the effect of temperature.The course of wort fermentation is most often monitored by measuring density by immersion saccharometer or digital densitometer; other methods include classical analysis or automatic analyzers. Another possibility is the measurement of refraction in the course of fermentation. When the original refraction or wort extract is known, refraction unambiguously determines the apparent extract or degree of attenuation. A refractometer with a scale in Brix degrees can be used similarly as a saccharometer having a scale in mass percent of sucrose. In the range of 0-16 mass % sucrose and 0-8% ethanol refraction is a linear function of concentration; this allows us to calculate concentration of ethanol, real extract and also an apparent extract in the course of fermentation from the values of actual and original refraction. Examples are given of measurement and instrument calibration. The measurements can be done with simple and inexpensive refractometers with computing compensation of the effect of temperature.

The aim of this work was the investigation of wort production for beer by the application of triticale malt, as the partial substitute for barley malt in grist. For wort production, three series of experiments were carried out in which malts were produced from three different triticale varieties taken from experimental fields Rimski Sancevi location (Serbia), crop 2006. Experiments were carried out on laboratory scale by applying infusion procedure for wort production. The obtained results indicate that the application of triticale malt gave worts that had good analytical quality parameters.

Introduction. Beer that is made from hops or hop products of certain breeding varieties, varies considerably in the nature of bitterness, taste and aroma. This is due to the peculiarity of the biochemical composition of bitter substances, polyphenolic compounds and essential oil of hop of aromatic and bitter varieties. The aim of the study is to use in brewing the CO2-extract and hop with a low content of alpha-acids, which can be the waste in the production of pellets 45, and to invent methods for its rational using. Materials and methods. Aromatic hops varieties with low alpha-acids, CO2-extract and beer made from them were investigated. High-performance liquid chromatography to determine the amount and composition of the bitter substances of hops, CO2-extracts and their conversion products in the brewing process and spectrophotometric quality control methods for the bitter taste of hopped wort and finished beer were used. Results. When we use in brewing CO2-extract and a thinaromatic hop with a low content of alpha-acids in optimal proportions, polyphenols of low-hops help to remove highmolecular polypeptides from the wort by coagulation with the formation of complexes. Thanks to this, a higher colloidal resistance of beer is achieved and the degree of use of bitter substances is increased by 15–20%. Beer that was prepared with the using of 40% wort, bitterness of aromatic low-hops and 60% bitterness due to CO2-extract, has had the best flavor and aromatic qualities. Beer in which extract and aromatic hops was used in a proportion of 40:60% was not much different. Polyphenols and beta-fraction of aromatic low-hops hops positively influence the coarse bitterness of the CO2-extract, softening and smoothing it, making the common bitterness of the beer balanced. Also, when we use these proportions, a maximum decrease in the index of high molecular weight polypeptides is observed, which predicts a high colloidal persistence of beer. When we use in brewing only a CO2-extract, it is impossible to obtain beer with high taste qualities. However, an excessive amount of hoppy polyphenols leads to an astringent taste in beer. Conclusions. Aromatic hop with a low alpha-acid content can be used in brewing as a polyphenol additive in combination with a CO2-extract, taking into account the quantitative content and qualitative composition of hop products and adhering to a certain technology of making beer. [ABSTRACT FROM AUTHOR]

Fermentability is an important trait for the brewing industry. Current industry methods lack the predictive capacity to accurately estimate how well a wort will ferment in the brewhouse. Wort from two mashing styles (high-temperature infusion and low-temperature ramping), and under varying grist to liquor (G:L) ratios, were produced and the differences in maltose, maltotriose and glucose were measured. The two mashing styles showed differences in original extract (Plato) values between the G:L ratios with a 1:2 G:L having the highest original extract. Maltose was the most abundant sugar in all sample types. All worts were scanned using Fourier transform infrared (FTIR) and the spectra also showed differences between the original extract and final extract with most of the changes around the spectral region associated with carbohydrates, a result of sugar utilization by the yeast. FTIR calibrations for extract and fermentable sugars all had r2 values >0.98, with ratio of standard error of prediction to standard deviation >5. The results indicated changing fermentable sugar levels, thus making a prediction of fermentability possible. The FTIR also provided a rapid measure of changes in the fermentable sugar profile, which could assist maltsters and brewers in monitoring malt and beer quality. 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]

In recent decades, research in barley has led to improvements in several biochemical and chemical characteristics (e.g. protein, starch, β glucans) associated with malt composition and end product quality (e.g. beer). Although lipids and fatty acids (FA) represent between 1 to 3% of the grain weight (dw), they can play an important role in barley grain and malt derived materials. However, the role of lipids and FA in both barley and malt quality is still not well understood. The aim of this article is to provide an overview on the role of lipids and FA in the chemical and industrial properties of barley grain, malt and wort. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

This article describes the ways of analytical determination of polyphenols in brewing. The methods for this determination are divided into two groups, analytical methods for group determination and determination of individual polyphenols. The group methods are for the determination of anthocyanogens, tanoids and flavonoids. For the determination of individuals polyphenols is the most widespread method HPLC (reverse phase) with different types of detection. Less widespread method is GC with MS detection, from point of view analyte derivatization.This article describes the ways of analytical determination of polyphenols in brewing. The methods for this determination are divided into two groups, analytical methods for group determination and determination of individual polyphenols. The group methods are for the determination of anthocyanogens, tanoids and flavonoids. For the determination of individuals polyphenols is the most widespread method HPLC (reverse phase) with different types of detection. Less widespread method is GC with MS detection, from point of view analyte derivatization.

An increased content of calcium in mash goods should contribute to precipitation of malt oxalates in the course of mashing. Further, calcium protects enzymes that participate in the mashing process from early inactivation. It is even possible to assume a slight decrease of pH of mashes and hopped wort to the technologically favourable values. The increased content of calcium in unhopped wort may also have positive effect on coagulation of proteins during wort boiling. The publication summarizes the experiences in additioning of calcium gained in the brewery Plzeňský Prazdroj, a.s. In the course of trial brews, the first portion of calcium was added into mash goods and the second one before the beginning of wort boiling. The quantity was determined so that the cold hopped wort would contain c. 80 mg/l Ca. In addition to common analyses, even the content of amino nitrogen (FAN), the coagulatable nitrogen, the content of oxalates and the clarity of drawn-off hopped wort were. studied. During fermentation, we targeted quality and quantity of separated yeast and, as regards the packed beer, apart of the common analyses even the contents of calcium, oxalates and the value of the coagulatable nitrogen. The practical results confirmed our theoretic anticipations and displayed that the addition of calcium increases the boiling yield, contributes to better yeast sedimentation and markedly reduces the risk of oxalate turbidity and gushing in racked beer.An increased content of calcium in mash goods should contribute to precipitation of malt oxalates in the course of mashing. Further, calcium protects enzymes that participate in the mashing process from early inactivation. It is even possible to assume a slight decrease of pH of mashes and hopped wort to the technologically favourable values. The increased content of calcium in unhopped wort may also have positive effect on coagulation of proteins during wort boiling. The publication summarizes the experiences in additioning of calcium gained in the brewery Plzeňský Prazdroj, a.s. In the course of trial brews, the first portion of calcium was added into mash goods and the second one before the beginning of wort boiling. The quantity was determined so that the cold hopped wort would contain c. 80 mg/l Ca. In addition to common analyses, even the content of amino nitrogen (FAN), the coagulatable nitrogen, the content of oxalates and the clarity of drawn-off hopped wort were. studied. During fermentation, we targeted quality and quantity of separated yeast and, as regards the packed beer, apart of the common analyses even the contents of calcium, oxalates and the value of the coagulatable nitrogen. The practical results confirmed our theoretic anticipations and displayed that the addition of calcium increases the boiling yield, contributes to better yeast sedimentation and markedly reduces the risk of oxalate turbidity and gushing in racked beer.

Ethanol, carbon dioxide and glycerol are the major products produced by yeast during wort fermentation but they have little impact on beer and spirit flavour. It is the type and concentration of secondary metabolites that can determine overall beer flavour. These compounds are (but not only) primarily: higher alcohols, esters, carbonyls and sulphur compounds—inorganic and organic. There are a number of factors that can modify the balance of these compounds most of which are discussed in this review paper.

Measurement of beer and intermediate hazes is an important part of modern brewing technology automation and control including laboratory analyses, total quality control and production of the shelf life of the final products. Regardless the fact that present brewers have at the disposal throughout theoretical and practical knowledge produce beer of market demanded product shelf life and appropriate colloidal or physical stability, time to time unwonted fluctuation of the product quality and process troubles can occur due to complicated mechanism of the ageing interactions of beer and intermediate colloid leading to business loss. At least, but not last a complex analyses of the processes of beer colloidal ageing is important for the knowledge and monitoring of flavour staling since both ageing processes are influenced by temperatures and other physical-chemical factors. One of the ways which can limit causes leading to unwanted beer ageing and improve quality of the final product is the innovation of both analytical methods and techniques based on beer and intermediates haze measurements enabling more precise and effective analyses of their colloidal and possibly flavour properties as well. It is shown in the present paper that substantial improvements is analyses of beer and intermediates colloids can be approached by innovative conception of unified brewing laboratory, bottle rotating turbidimeter capable of performing beer thermal ageing tests on intact commercial bottles provided with the modules from turbidimetric titrations of small volume samples in chemical tubes or vials or even more with process flow-through haze measuring cell simultaneously and two scattering angles, thus enabling to differ changes in the size of haze particles during ageing of technological processes. By means of complementation of turbidimetric titrations with simultaneous pH and or conductometric measurements the developed technique gives than cost effective estimation of basic electrokinetic parameters of beer and intermediates colloids which play and important role in beer ageing processes.(In Czech, English summary only)

The research center Meura Technologies of Belgian company Meura has studied an oxygen effect during malt grinding, mashing, mash filtration in mash filter and fermentation upon to changes of beer's flawour during storage. The negative influence of the oxygen upon beer taste was determined, the beer brewed at present of oxygen obtained a cardboard flavour while ageing. It was developed oxygenation controlling technology, that enables to reduce an oxygen uptake during malt grinding, mash and lauter process and avoids wort oxidation. For grinding will be used a disc mill in which the malt is grinded under water and CO2 protection. According to new method the yeast will be preoxygenated (by pure oxygen) in membrane sparger instead of the wort aeration. Beer, produced under reduction of oxidation, had a better taste properties while ageing, to compare with another one, brewed in traditional way(In Czech, English summary only)