A. Mikyška, K. Štěrba, Martin Slabý, V. Nesvadba, J. Charvátová
Characterization of varietal profiles of hop secondary metabolites in beer is of considerable importance for hop growing and brewing. This three-year study focused on pilot brewing tests of three new Saaz derived hop varieties, namely Saaz Brilliant, Saaz Shine and Saaz Comfort. The sensory profiles of kettle and kettle+dry single hopped beers were monitored. At the same time, the impact of dry hopping technology on sensory perception of final beers and changes in volatile compounds was investigated. Pilot brews (200 l) of 12% pale lager were prepared in kettle and kettle+dry variants using the new Czech varieties and traditional Saaz as a control sample. Essential oils in beers were determined by GC/MS-MS method with the aim to clarify links to the beer sensory profile of both, kettle and dry hopping mode. The descriptive sensory method of hop-derived aromas and the triangle tests were employed to determine the sensory quality of beer. The overall sensory impression of beers from all tested varieties was at least comparable to traditional Saaz, and Saaz Comfort even reached better evaluation. The profile of essential oils and hop flavours in beer was partially different, however it was not rated worse than Saaz. The kettle+dry hopped beers of new varieties were significantly different from Saaz in the triangle test, Saaz Brilliant was preferred over the Saaz. The results showed considerable potential of new varieties for the production of interesting and taste-specific beers and the enrichment of the spectrum of fine aroma varieties of Czech hops.
{"title":"Brewing tests of new fine aroma hop varieties (Humulus lupulus L.) Saaz Brilliant, Saaz Comfort and Saaz Shine","authors":"A. Mikyška, K. Štěrba, Martin Slabý, V. Nesvadba, J. Charvátová","doi":"10.18832/kp2021.67.464","DOIUrl":"https://doi.org/10.18832/kp2021.67.464","url":null,"abstract":"Characterization of varietal profiles of hop secondary metabolites in beer is of considerable importance for hop growing and brewing. This three-year study focused on pilot brewing tests of three new Saaz derived hop varieties, namely Saaz Brilliant, Saaz Shine and Saaz Comfort. The sensory profiles of kettle and kettle+dry single hopped beers were monitored. At the same time, the impact of dry hopping technology on sensory perception of final beers and changes in volatile compounds was investigated. Pilot brews (200 l) of 12% pale lager were prepared in kettle and kettle+dry variants using the new Czech varieties and traditional Saaz as a control sample. Essential oils in beers were determined by GC/MS-MS method with the aim to clarify links to the beer sensory profile of both, kettle and dry hopping mode. The descriptive sensory method of hop-derived aromas and the triangle tests were employed to determine the sensory quality of beer. The overall sensory impression of beers from all tested varieties was at least comparable to traditional Saaz, and Saaz Comfort even reached better evaluation. The profile of essential oils and hop flavours in beer was partially different, however it was not rated worse than Saaz. The kettle+dry hopped beers of new varieties were significantly different from Saaz in the triangle test, Saaz Brilliant was preferred over the Saaz. The results showed considerable potential of new varieties for the production of interesting and taste-specific beers and the enrichment of the spectrum of fine aroma varieties of Czech hops.","PeriodicalId":17834,"journal":{"name":"Kvasny prumysl","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90838664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The article deals with the harvest forecast of the content of bitter acids in Czech hop varieties harvested in 2020. This is presented in the context of long-term trends in the content and composition of bitter acids analogues and the stability of the varietal characteristics in the aforementioned harvest. This analysis is usually available at the end of the calendar year. 180 hop samples were analysed using EBC 7.7 (HPLC) method. The α-acids content in the most important variety of Saaz (3.65% in dry matter) was 12.8% rel. higher than in the 2019 harvest and 4.2% rel. higher than the 28-year average. The α-acids content in Saaz Late (3.23%), Sladek (7.9%), Kazbek (6.4%) and Agnus (12.4%) was significantly higher than both the long-term averages for the varieties and the harvest of 2019. The Premiant (8.0%) variety was close to the long-term average. The ratio of α-/β-acids, the relative content of cohumulone and the relative content of colupulone were consistent with long-term averages of the tested varieties. It was confirmed that the harvest forecast provides timely information on the α-acids content of the given harvest, the results being in good agreement with the values of the final evaluation of all harvested hops.
{"title":"Analysis and prognosis of bitter acids content in Czech hop varieties – year 2020 and long-term comparisons and trends","authors":"Alexandr MikyĹĄka, Marie JurkovĂĄ","doi":"10.18832/kp2021.67.474","DOIUrl":"https://doi.org/10.18832/kp2021.67.474","url":null,"abstract":"The article deals with the harvest forecast of the content of bitter acids in Czech hop varieties harvested in 2020. This is presented in the context of long-term trends in the content and composition of bitter acids analogues and the stability of the varietal characteristics in the aforementioned harvest. This analysis is usually available at the end of the calendar year. 180 hop samples were analysed using EBC 7.7 (HPLC) method. The α-acids content in the most important variety of Saaz (3.65% in dry matter) was 12.8% rel. higher than in the 2019 harvest and 4.2% rel. higher than the 28-year average. The α-acids content in Saaz Late (3.23%), Sladek (7.9%), Kazbek (6.4%) and Agnus (12.4%) was significantly higher than both the long-term averages for the varieties and the harvest of 2019. The Premiant (8.0%) variety was close to the long-term average. The ratio of α-/β-acids, the relative content of cohumulone and the relative content of colupulone were consistent with long-term averages of the tested varieties. It was confirmed that the harvest forecast provides timely information on the α-acids content of the given harvest, the results being in good agreement with the values of the final evaluation of all harvested hops.","PeriodicalId":17834,"journal":{"name":"Kvasny prumysl","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82598146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Olšovská, L. Kyselová, P. Kubizniaková, Martin Slabý
Beer is a complex mixture consisting of hundreds of chemical substances. Some of them are macromolecules, such as proteins and polysaccharides that together with polyphenolic compounds form poorly soluble complexes causing beer turbidity or cold colloidal turbidity. Furthermore, beer turbidity can be caused also by procedural particles entering into beer during brewing process (filtration and stabilization aids) or by foreign particles from external environment (mechanical impurities). If turbidity, sediment or individual particles occur in filtered and stabilized beer, their origin must be determined since brilliant visual impression of the filtered beer influences an opinion of customers on a specific product. The identification of different species of turbidity using microscopic image, particle staining, enzymatic analysis or identification precursors is clearly described in this paper. The study includes pictorial documentation of various particles that may be part of beer turbidity.
{"title":"Non-microbiological turbidity of beer: Part 1 – semireview","authors":"J. Olšovská, L. Kyselová, P. Kubizniaková, Martin Slabý","doi":"10.18832/kp2021.67.484","DOIUrl":"https://doi.org/10.18832/kp2021.67.484","url":null,"abstract":"Beer is a complex mixture consisting of hundreds of chemical substances. Some of them are macromolecules, such as proteins and polysaccharides that together with polyphenolic compounds form poorly soluble complexes causing beer turbidity or cold colloidal turbidity. Furthermore, beer turbidity can be caused also by procedural particles entering into beer during brewing process (filtration and stabilization aids) or by foreign particles from external environment (mechanical impurities). If turbidity, sediment or individual particles occur in filtered and stabilized beer, their origin must be determined since brilliant visual impression of the filtered beer influences an opinion of customers on a specific product. The identification of different species of turbidity using microscopic image, particle staining, enzymatic analysis or identification precursors is clearly described in this paper. The study includes pictorial documentation of various particles that may be part of beer turbidity.","PeriodicalId":17834,"journal":{"name":"Kvasny prumysl","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84979147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hop breeding in the Czech Republic develops a number of flavour hops. The Kazbek hop variety was registered in 2008 and the Mimosa variety in 2019. The best 7 hop genotypes were selected from breeding materials between the years 2014 and 2019. Kazbek, 5512 (Ceres) and 5571 (Eris) expressed a clear citrusy flavour. Mimosa, 5495 (Juno) and 5520 (Saturn) could be described as fruity while 5164 (Uran), 5540 (Jupiter) and 5580 (Pluto) as rather spicy. Genotype 5164 showed the highest aroma intensity, content of alpha acids (11.51% w/w) and alpha/beta ratio (2.20). Whereas Mimosa demonstrated the highest content of beta acids (5.56% w/w) and the lowest alpha/beta ratio (0.28), 5571 and 5520 had the highest cohumulone amount (49.19% rel. and 47.35% rel., respectively). In contrast, 5580 were distinguished by the lowest cohumulone (21.28% rel.). The highest amount of hop oils was determined in 5164 (1.77 w/w) and 5520 (1.53 w/w). 5164, 5540 and 5495 show a myrcene level above 40% rel. On the other hand, Kazbek, Mimosa and 5571 indicated a myrcene content below 35%. The highest level of farnesene (12.50% rel.) was detected in 5164; in other samples the values were below 1% rel. Mimosa showed the highest concentration of selinenes (32.75% rel.); other samples demonstrated selinenes below 10% rel. The Kazbek variety is the foundation for the breeding of flavour hops in the Czech Republic, and therefore it is the mother plant of genotypes 5495, 5512, 5520, 5540 and 5571. Harmonie is the mother plant of genotype 5580.
{"title":"Breeding of flavour hops in the Czech Republic","authors":"V. Nesvadba, J. Charvátová, S. Trnková","doi":"10.18832/KP2019.66.366","DOIUrl":"https://doi.org/10.18832/KP2019.66.366","url":null,"abstract":"Hop breeding in the Czech Republic develops a number of flavour hops. The Kazbek hop variety was registered in 2008 and the Mimosa variety in 2019. The best 7 hop genotypes were selected from breeding materials between the years 2014 and 2019. Kazbek, 5512 (Ceres) and 5571 (Eris) expressed a clear citrusy flavour. Mimosa, 5495 (Juno) and 5520 (Saturn) could be described as fruity while 5164 (Uran), 5540 (Jupiter) and 5580 (Pluto) as rather spicy. Genotype 5164 showed the highest aroma intensity, content of alpha acids (11.51% w/w) and alpha/beta ratio (2.20). Whereas Mimosa demonstrated the highest content of beta acids (5.56% w/w) and the lowest alpha/beta ratio (0.28), 5571 and 5520 had the highest cohumulone amount (49.19% rel. and 47.35% rel., respectively). In contrast, 5580 were distinguished by the lowest cohumulone (21.28% rel.). The highest amount of hop oils was determined in 5164 (1.77 w/w) and 5520 (1.53 w/w). 5164, 5540 and 5495 show a myrcene level above 40% rel. On the other hand, Kazbek, Mimosa and 5571 indicated a myrcene content below 35%. The highest level of farnesene (12.50% rel.) was detected in 5164; in other samples the values were below 1% rel. Mimosa showed the highest concentration of selinenes (32.75% rel.); other samples demonstrated selinenes below 10% rel. The Kazbek variety is the foundation for the breeding of flavour hops in the Czech Republic, and therefore it is the mother plant of genotypes 5495, 5512, 5520, 5540 and 5571. Harmonie is the mother plant of genotype 5580.","PeriodicalId":17834,"journal":{"name":"Kvasny prumysl","volume":"35 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85753683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. Strakova, V. Nesvadba, J. Křivánek, Martin Slabý, Tomáš Vrzal, J. Charvátová, R. Cerkal, J. Olšovská
In the Czech Republic breeding of new hop varieties is traditionally performed. Its properties correspond with the requirements and interests of end users, in particular hop growers, brewers and especially beer consumers, who with an increasing favor taste new types of beer. The study presents 8 new promising aromatic genotypes, whose major part (Uran, Juno, Ceres, Jupiter, Eris and Most) is already in the registration process of ÚKZÚZ of the Czech Republic (Central Institute for Supervising and Testing in Agriculture CISTA). The tested genotypes were described using brewing tests. Regarding the character of the tested hop varieties, there was chosen a uniform and simple infusion recipe with a top fermentation and dry hopping. The final beer samples were evaluated using chemical and sensorial analyses focusing on a hop aroma. All beer samples were rated as very good, the overall impression of the samples on the scale of 1 to 9 ranged from 2.9 to 3.1. The hop aroma and also bitterness character of the final beer samples were evaluated of high quality. Depending on the hop profile of the beer samples, there were suggested beer styles where the given varieties can be successfully used. These results indicate a high potential of these varieties for the use in brewing practice. Finally, the probability of perceiving a particular hop aroma in beer given by perceiving the aroma in hops was determined by Bayes’ theorem. It was found that probability particularly for spicy, resinous, herbal, citrusy, floral, fruity and grassy aroma was 100, 100, 100, 40, 38, 43, and 100%, respectively.
{"title":"Sensorial character of beer dry hopped with new Czech genotypes of hops with a specific flavor","authors":"L. Strakova, V. Nesvadba, J. Křivánek, Martin Slabý, Tomáš Vrzal, J. Charvátová, R. Cerkal, J. Olšovská","doi":"10.18832/KP2019.66.372","DOIUrl":"https://doi.org/10.18832/KP2019.66.372","url":null,"abstract":"In the Czech Republic breeding of new hop varieties is traditionally performed. Its properties correspond with the requirements and interests of end users, in particular hop growers, brewers and especially beer consumers, who with an increasing favor taste new types of beer. The study presents 8 new promising aromatic genotypes, whose major part (Uran, Juno, Ceres, Jupiter, Eris and Most) is already in the registration process of ÚKZÚZ of the Czech Republic (Central Institute for Supervising and Testing in Agriculture CISTA). The tested genotypes were described using brewing tests. Regarding the character of the tested hop varieties, there was chosen a uniform and simple infusion recipe with a top fermentation and dry hopping. The final beer samples were evaluated using chemical and sensorial analyses focusing on a hop aroma. All beer samples were rated as very good, the overall impression of the samples on the scale of 1 to 9 ranged from 2.9 to 3.1. The hop aroma and also bitterness character of the final beer samples were evaluated of high quality. Depending on the hop profile of the beer samples, there were suggested beer styles where the given varieties can be successfully used. These results indicate a high potential of these varieties for the use in brewing practice. Finally, the probability of perceiving a particular hop aroma in beer given by perceiving the aroma in hops was determined by Bayes’ theorem. It was found that probability particularly for spicy, resinous, herbal, citrusy, floral, fruity and grassy aroma was 100, 100, 100, 40, 38, 43, and 100%, respectively.","PeriodicalId":17834,"journal":{"name":"Kvasny prumysl","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83844707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Kubizniaková, M. Brožová, K. Štulíková, Eva Vontrobovă, Katarína Hanzalíková, D. Matoulková
The growth of 7 strains belonging to the order of Enterobacterales, represented by the species of Citrobacter Freundii, Enterobacter cloacae, Escherichia coli, Klebsiella oxytoca, Obesumbacterium proteus, Rahnella aquatilis, Raoultella terrigena, Serratia marcescens and Shimwellia pseudoproteus, was monitored on selected cultivation media. Three types of agars - Endo, MacConkey and Chromocult Coliform agar together with two incubation temperatures of 28 and 37 °C were tested under aerobic conditions. The aim of the study was to detect such essential enterobacteria harmful to beer that cannot be proven at 37 °C, which is the temperature usually used in operational laboratories in breweries. Our results showed that most of the tested strains of enterobacteria were able to grow at 28 °C on all selected types of agar. The exception was just the representatives detection of which is problematic at 37 °C. Nevertheless, a little or no growth was always observed on just one of the tested media.
{"title":"Microbiology of brewing production - bacteria of the order Enterobacterales and culture methods for their detection","authors":"P. Kubizniaková, M. Brožová, K. Štulíková, Eva Vontrobovă, Katarína Hanzalíková, D. Matoulková","doi":"10.18832/kp2019.66.345","DOIUrl":"https://doi.org/10.18832/kp2019.66.345","url":null,"abstract":"The growth of 7 strains belonging to the order of Enterobacterales, represented by the species of Citrobacter Freundii, Enterobacter cloacae, Escherichia coli, Klebsiella oxytoca, Obesumbacterium proteus, Rahnella aquatilis, Raoultella terrigena, Serratia marcescens and Shimwellia pseudoproteus, was monitored on selected cultivation media. Three types of agars - Endo, MacConkey and Chromocult Coliform agar together with two incubation temperatures of 28 and 37 °C were tested under aerobic conditions. The aim of the study was to detect such essential enterobacteria harmful to beer that cannot be proven at 37 °C, which is the temperature usually used in operational laboratories in breweries. Our results showed that most of the tested strains of enterobacteria were able to grow at 28 °C on all selected types of agar. The exception was just the representatives detection of which is problematic at 37 °C. Nevertheless, a little or no growth was always observed on just one of the tested media.","PeriodicalId":17834,"journal":{"name":"Kvasny prumysl","volume":"21 1","pages":"345-350"},"PeriodicalIF":0.0,"publicationDate":"2020-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81094109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Peter Vaštík, D. Šmogrovičová, Valentína Kafková, P. Sulo, K. Furdíková, I. Špánik
Non-Saccharomyces yeast strains Saccharomycodes ludwigii, Schizosaccharomyces pombe, Lachancea fermentati and Pichia angusta together with a hybrid yeast strain cross-bred between genetically modified Saccharomyces cerevisiae W303-1A G418R and Saccharomyces eubayanus as well as the parent yeasts of the hybrid were studied for potential use for non-alcoholic beer production. The hybrid yeast, its Saccharomyces cerevisiae W303-1A G418R parent and Saccharomycodes ludwigii were not able to metabolise maltose during Durham tube tests. Schizosaccharomyces pombe, Lachancea fermentati and Pichia angusta metabolised maltose, however, showed limited ethanol production. Parameters, volatile and non-volatile organic compounds of beers produced by the studied yeast were analysed and compared to a beer produced by bottom fermented brewer’s yeast Saccharomyces pastorianus.
{"title":"Production and characterisation of non-alcoholic beer using special yeast","authors":"Peter Vaštík, D. Šmogrovičová, Valentína Kafková, P. Sulo, K. Furdíková, I. Špánik","doi":"10.18832/kp2019.66.336","DOIUrl":"https://doi.org/10.18832/kp2019.66.336","url":null,"abstract":"Non-Saccharomyces yeast strains Saccharomycodes ludwigii, Schizosaccharomyces pombe, Lachancea fermentati and Pichia angusta together with a hybrid yeast strain cross-bred between genetically modified Saccharomyces cerevisiae W303-1A G418R and Saccharomyces eubayanus as well as the parent yeasts of the hybrid were studied for potential use for non-alcoholic beer production. The hybrid yeast, its Saccharomyces cerevisiae W303-1A G418R parent and Saccharomycodes ludwigii were not able to metabolise maltose during Durham tube tests. Schizosaccharomyces pombe, Lachancea fermentati and Pichia angusta metabolised maltose, however, showed limited ethanol production. Parameters, volatile and non-volatile organic compounds of beers produced by the studied yeast were analysed and compared to a beer produced by bottom fermented brewer’s yeast Saccharomyces pastorianus.","PeriodicalId":17834,"journal":{"name":"Kvasny prumysl","volume":"40 1","pages":"336-344"},"PeriodicalIF":0.0,"publicationDate":"2020-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91160812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Based on the European regulation, the Czech Association of Breweries and Malthouses recommends 2.5 mg/kg as maximum permitted concentration of melamine for beer, barley, malt, hop, and their products. For this reason, the first analytical method for melamine determination in beer and beer-type beverages was developed. The sample preparation included ion-exchange solid-phase extraction and subsequent derivatization with BSTFA. Qualitative and quantitative analysis was performed by gas chromatography with tandem mass spectrometry. Validation parameters of the method, such as limits of detection and quantification were 0.1 mg/L and 0.4 mg/L, respectively. Extended uncertainty of the final method was evaluated to 0.1 mg/L. The method was applied on twenty samples of beer lagers, or other beer styles; all had the level of melamine under the limit of quantification (< 0.4 mg/L).
{"title":"Development of a method for melamine determination in beer and beer-type beverages by GC-MS/MS","authors":"M. Malečková, Tomáš Vrzal, J. Olšovská","doi":"10.18832/kp2019.66.331","DOIUrl":"https://doi.org/10.18832/kp2019.66.331","url":null,"abstract":"Based on the European regulation, the Czech Association of Breweries and Malthouses recommends 2.5 mg/kg as maximum permitted concentration of melamine for beer, barley, malt, hop, and their products. For this reason, the first analytical method for melamine determination in beer and beer-type beverages was developed. The sample preparation included ion-exchange solid-phase extraction and subsequent derivatization with BSTFA. Qualitative and quantitative analysis was performed by gas chromatography with tandem mass spectrometry. Validation parameters of the method, such as limits of detection and quantification were 0.1 mg/L and 0.4 mg/L, respectively. Extended uncertainty of the final method was evaluated to 0.1 mg/L. The method was applied on twenty samples of beer lagers, or other beer styles; all had the level of melamine under the limit of quantification (< 0.4 mg/L).","PeriodicalId":17834,"journal":{"name":"Kvasny prumysl","volume":"30 1","pages":"331-335"},"PeriodicalIF":0.0,"publicationDate":"2020-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76658083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This article deals with calculation possibilities and the control of basic parameters of beer on the basis of knowledge of two parameters. The importance of this method increases with the development of craft beer production in our country (mini-breweries, home brewing). The calculations are based on Balling's equations, alcohol factors and attenuation quotients, which have been published unchanged since at least 1876. In Balling's time, they were used to determine an extract with a specific gravities of 17.5 °C/17.5 °C. In current brewing, specific gravities of 20 °C/20 °C are used. For this reason, new alcohol factors of apparent attenuation were derived, and based on linear regression, regression coefficients of the dependence of the alcohol factor of apparent attenuation on the extract in original wort were calculated. Some variants of calculations based on two input parameters were incorporated into the beer composition calculator using formulas that replace extract and alcohol tables. The accuracy of the results from the calculator was checked with analyses from the Anton Paar automatic analyzer and with analyses obtained by the distillation method. The calculator is available at www.balling.cz.
{"title":"Balling's attenuation theory and beer composition calculator","authors":"Vilém Nohel","doi":"10.18832/kp2019.66.351","DOIUrl":"https://doi.org/10.18832/kp2019.66.351","url":null,"abstract":"This article deals with calculation possibilities and the control of basic parameters of beer on the basis of knowledge of two parameters. The importance of this method increases with the development of craft beer production in our country (mini-breweries, home brewing). The calculations are based on Balling's equations, alcohol factors and attenuation quotients, which have been published unchanged since at least 1876. In Balling's time, they were used to determine an extract with a specific gravities of 17.5 °C/17.5 °C. In current brewing, specific gravities of 20 °C/20 °C are used. For this reason, new alcohol factors of apparent attenuation were derived, and based on linear regression, regression coefficients of the dependence of the alcohol factor of apparent attenuation on the extract in original wort were calculated. Some variants of calculations based on two input parameters were incorporated into the beer composition calculator using formulas that replace extract and alcohol tables. The accuracy of the results from the calculator was checked with analyses from the Anton Paar automatic analyzer and with analyses obtained by the distillation method. The calculator is available at www.balling.cz.","PeriodicalId":17834,"journal":{"name":"Kvasny prumysl","volume":"1 1","pages":"351-365"},"PeriodicalIF":0.0,"publicationDate":"2020-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83079670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Helena Pluháčková, T. Gregor, R. Boško, S. Běláková, Z. Svoboda, K. Benešová
This study investigated the possibilities of fortification of beer with various herbal extracts. The aim was to fortify beer with natural substances that have favourable effects on consumers ́ health. The tested beers were enriched with ethanol extracts of medicinal herbs (ribwort plantain, small leaved linden, purple coneflower, chamomile, sage) so that the sensory characters of the supplemented herbal extract created only an accompanying perception and the malt and hop flavour of beer was preserved. In the enriched beers, the contents of the selected phenolic substances and important essential oils were determined and sensory evaluation was performed. The content of phenolic substances increased the most in beer with linden (42.46 mg/l) and plantain (37.5 mg/l) extracts, approximately four times compared to the original beer (8.11 mg/l). Beer with sage and chamomile extract achieved the best sensory assessment, with components of essential oils added in units of ng/l of beer.
{"title":"Fortification of Beer with Extracts of the Selected Czech Medicinal Herbs and Plants","authors":"Helena Pluháčková, T. Gregor, R. Boško, S. Běláková, Z. Svoboda, K. Benešová","doi":"10.18832/kp2019.66.314","DOIUrl":"https://doi.org/10.18832/kp2019.66.314","url":null,"abstract":"This study investigated the possibilities of fortification of beer with various herbal extracts. The aim was to fortify beer with natural substances that have favourable effects on consumers ́ health. The tested beers were enriched with ethanol extracts of medicinal herbs (ribwort plantain, small leaved linden, purple coneflower, chamomile, sage) so that the sensory characters of the supplemented herbal extract created only an accompanying perception and the malt and hop flavour of beer was preserved. In the enriched beers, the contents of the selected phenolic substances and important essential oils were determined and sensory evaluation was performed. The content of phenolic substances increased the most in beer with linden (42.46 mg/l) and plantain (37.5 mg/l) extracts, approximately four times compared to the original beer (8.11 mg/l). Beer with sage and chamomile extract achieved the best sensory assessment, with components of essential oils added in units of ng/l of beer.","PeriodicalId":17834,"journal":{"name":"Kvasny prumysl","volume":"115 1","pages":"314-319"},"PeriodicalIF":0.0,"publicationDate":"2020-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75997233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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