Editing Yeast
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The beer filtration process reduces the contents of antioxidant phenolic compounds and melanoidins and the AOX of wort. During the cooling stage, the spontaneous adsorption of phenolic compounds and melanoidins on wort dregs and the polymerization and precipitation of catechins and epicatechins lead to the decrease of TPC in beer (Ruiz- Ruiz, Del Carmen Esapadas Aldana, Cruz, & Segura-Campos, 2020). With the increase of diatomite consumption, a large concentration of iron ions is introduced, which decreases the DPPH scavenging rate, because transition ions such as iron and copper play an important cat alytic role in the Fenton reaction, producing hydroxyl free radicals with high activity and reducing the oxidation resistance of beer (Jurková et al., 2012; Pascoe, Ames, & Chandra, 2003). The addition of tannins has an obvious effect on the rate of scavenging of DPPH free radicals, indicating that the addition of tannins will help to chelate iron ions and reduce the effect of iron ions in diatomite on beer. The reducing power of beer can be improved by maintaining pH within the range 4.3–4.4 (Han, 2016). After cooling and filtration, 6% of selenium is lost from the level in raw materials, and the total loss of selenium over the whole process of beer fermentation is 94% (Rodrigo et al., 2015). It can be seen that the percentage selenium loss is quite high, which deserves attention.<ref name=yangao/> | The beer filtration process reduces the contents of antioxidant phenolic compounds and melanoidins and the AOX of wort. During the cooling stage, the spontaneous adsorption of phenolic compounds and melanoidins on wort dregs and the polymerization and precipitation of catechins and epicatechins lead to the decrease of TPC in beer (Ruiz- Ruiz, Del Carmen Esapadas Aldana, Cruz, & Segura-Campos, 2020). With the increase of diatomite consumption, a large concentration of iron ions is introduced, which decreases the DPPH scavenging rate, because transition ions such as iron and copper play an important cat alytic role in the Fenton reaction, producing hydroxyl free radicals with high activity and reducing the oxidation resistance of beer (Jurková et al., 2012; Pascoe, Ames, & Chandra, 2003). The addition of tannins has an obvious effect on the rate of scavenging of DPPH free radicals, indicating that the addition of tannins will help to chelate iron ions and reduce the effect of iron ions in diatomite on beer. The reducing power of beer can be improved by maintaining pH within the range 4.3–4.4 (Han, 2016). After cooling and filtration, 6% of selenium is lost from the level in raw materials, and the total loss of selenium over the whole process of beer fermentation is 94% (Rodrigo et al., 2015). It can be seen that the percentage selenium loss is quite high, which deserves attention.<ref name=yangao/> | ||
SafaleTM S-04 is a maltotriose negative yeast, thus sugars remain into the beer contributing to sweet character to aroma and taste.<ref name=ligdef>Liguori L, De Francesco G, Orilio P, Perretti G, Albanese D. [https://link.springer.com/article/10.1007/s13197-020-04740-8 Influence of malt composition on the quality of a top fermented beer.] ''J Food Sci Technol.'' 2021;58:2295–2303.</ref> | SafaleTM S-04 is a maltotriose negative yeast, thus sugars remain into the beer contributing to sweet character to aroma and taste.<ref name=ligdef>Liguori L, De Francesco G, Orilio P, Perretti G, Albanese D. [https://link.springer.com/article/10.1007/s13197-020-04740-8 Influence of malt composition on the quality of a top fermented beer.] ''J Food Sci Technol.'' 2021;58:2295–2303.</ref> | ||
==Preparing yeast for fermentation== | |||
Rehydrating dry yeast | ===Rehydrating dry yeast=== | ||
*https://www.brunwater.com/articles/water-for-yeast-rehydration | *https://www.brunwater.com/articles/water-for-yeast-rehydration | ||
*https://www.homebrewtalk.com/threads/dry-yeast-rehydration.681608/ | *https://www.homebrewtalk.com/threads/dry-yeast-rehydration.681608/ | ||
Starters for liquid yeast | ===Starters for liquid yeast=== | ||
Yeast produce membrane lipids only when grown aerobically. In the initial growth phase, proper oxygen management leads to proper production and storage of sterols in the yeast cell, which can be shared with subsequent daughter cells. It is possible to increase yeast ethanol tolerance by promoting synthesis of sterols, by adding oxygen (air) in the starter and during fermentation. Yeast lees deplete the oxygen content and can impact the redox potential and formation of VSCs.<ref name="Zoecklein">Zoecklein B. [https://www. | Yeast produce membrane lipids only when grown aerobically. In the initial growth phase, proper oxygen management leads to proper production and storage of sterols in the yeast cell, which can be shared with subsequent daughter cells. It is possible to increase yeast ethanol tolerance by promoting synthesis of sterols, by adding oxygen (air) in the starter and during fermentation. Yeast lees deplete the oxygen content and can impact the redox potential and formation of VSCs.<ref name="Zoecklein">Zoecklein B. [https://www.apps.fst.vt.edu/extension/enology/EN/133.html Enology notes #133.] Wine/Enology Grape Chemistry Group at Virginia Tech. Published 2007. Accessed 2020.</ref> | ||
While oxidative stress is known to occur, is it significantly less that stress from carbon dioxide. High amounts of foam means that insufficient oxygen delivery is occurring.<ref>https://www.mbaa.com/publications/tq/tqPastIssues/2005/Abstracts/TQ-42-0128.htm</ref> | While oxidative stress is known to occur, is it significantly less that stress from carbon dioxide. High amounts of foam means that insufficient oxygen delivery is occurring.<ref>https://www.mbaa.com/publications/tq/tqPastIssues/2005/Abstracts/TQ-42-0128.htm</ref> | ||
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*https://www.homebrewtalk.com/threads/the-ideal-starter-transcript-of-an-article-on-braumagazin-de.679661/ | *https://www.homebrewtalk.com/threads/the-ideal-starter-transcript-of-an-article-on-braumagazin-de.679661/ | ||
Biomass may actually be more important that cell count with regard to pitch rate.<ref>[https:// | Biomass may actually be more important that cell count with regard to pitch rate.<ref>[https://www.milkthefunk.live/podcast/2019/12/6/wiki-kwiki-005-lance-shaner-of-omega-yeast-labs "Wiki Kwiki #005 - Lance Shaner of Omega Yeast Labs"] (at ~30 minutes) Milk the Funk podcast, December 2019.</ref> However this isn't easy to measure at home. Pitching rate calculators are still useful for determining correct pitch rate. | ||
Yeast in worts rich in glucose may not be able to adapt to metabolize maltose and maltotriose, leading to slow or stuck fermentations.<ref name=bsp>Briggs DE, Boulton CA, Brookes PA, Stevens R. [[Library|''Brewing Science and Practice.'']] Woodhead Publishing Limited and CRC Press LLC; 2004.</ref> | Yeast in worts rich in glucose may not be able to adapt to metabolize maltose and maltotriose, leading to slow or stuck fermentations.<ref name=bsp>Briggs DE, Boulton CA, Brookes PA, Stevens R. [[Library|''Brewing Science and Practice.'']] Woodhead Publishing Limited and CRC Press LLC; 2004.</ref> | ||
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*https://www.tandfonline.com/doi/abs/10.1094/ASBCJ-58-0014 | *https://www.tandfonline.com/doi/abs/10.1094/ASBCJ-58-0014 | ||
slow/stuck fermentation | ==slow/stuck fermentation== | ||
*https://www.sciencedirect.com/science/article/abs/pii/S1389172301800633 | *https://www.sciencedirect.com/science/article/abs/pii/S1389172301800633 | ||
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[[Stuck fermentation]] | [[Stuck fermentation]] | ||
Nutrition | ==Nutrition== | ||
Brewer's yeast strains cannot assimilate proteins and longer chain peptides due to the fact that cells hardly secrete proteases during brewing. The assimilable nitrogenous compounds for brewer's yeast are known as free amino nitrogen (FAN) which can be defined as the sum of FAA, ammonium ions, and to a lesser extent, di- and tripeptides.<ref name=lei>Lei H, Zheng L, Wang C, Zhao H, Zhao M. [https://www.sciencedirect.com/science/article/abs/pii/S0168160512006150 Effects of worts treated with proteases on the assimilation of free amino acids and fermentation performance of lager yeast.] ''Int J Food Microbiol.'' 2013;161(2):76–83.</ref> The transport of FAA across the cell membrane is active, driven by the proton gradient via specific and general amino acid permeases. FAA have been categorized into four groups in ale yeast on the basis of their assimilation patterns (Jones and Pierce, 1964). In this model, group A is reported to be assimilated immediately after the yeast cells come into contact with wort and almost totally consumed after a few hours of fermentation. Group B is taken up more slowly, but assimilated gradually throughout fermentation. Group C is not utilized until group A have disappeared from the wort. Pro is the sole member of group D and is also the least preferred amino acid by brewer's yeast, because its dissimilation requires the presence of a mitochondrial oxidase which is inactive under anaerobic conditions. However, it has been proven that this assimilation pattern is often specific to the conditions employed and among them the yeast strain's nutritional preferences is perhaps more significant. Increasing the FAN has minor and somewhat unpredictable effects on yeast growth and attenuation. | Brewer's yeast strains cannot assimilate proteins and longer chain peptides due to the fact that cells hardly secrete proteases during brewing. The assimilable nitrogenous compounds for brewer's yeast are known as free amino nitrogen (FAN) which can be defined as the sum of FAA, ammonium ions, and to a lesser extent, di- and tripeptides.<ref name=lei>Lei H, Zheng L, Wang C, Zhao H, Zhao M. [https://www.sciencedirect.com/science/article/abs/pii/S0168160512006150 Effects of worts treated with proteases on the assimilation of free amino acids and fermentation performance of lager yeast.] ''Int J Food Microbiol.'' 2013;161(2):76–83.</ref> The transport of FAA across the cell membrane is active, driven by the proton gradient via specific and general amino acid permeases. FAA have been categorized into four groups in ale yeast on the basis of their assimilation patterns (Jones and Pierce, 1964). In this model, group A is reported to be assimilated immediately after the yeast cells come into contact with wort and almost totally consumed after a few hours of fermentation. Group B is taken up more slowly, but assimilated gradually throughout fermentation. Group C is not utilized until group A have disappeared from the wort. Pro is the sole member of group D and is also the least preferred amino acid by brewer's yeast, because its dissimilation requires the presence of a mitochondrial oxidase which is inactive under anaerobic conditions. However, it has been proven that this assimilation pattern is often specific to the conditions employed and among them the yeast strain's nutritional preferences is perhaps more significant. Increasing the FAN has minor and somewhat unpredictable effects on yeast growth and attenuation. | ||
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Nitrogen is generally plentiful in wort and typically does not require supplementation for beer production.<ref name="Ferreira"/><ref name=jonesbudde>Jones BL, Budde AD. [https://www.sciencedirect.com/science/article/abs/pii/S0733521004001067 How various malt endoproteinase classes affect wort soluble protein levels.] ''J Cereal Sci.'' 2005;41(1):95–106.</ref> The concentration of the amino acids isoleucine, valine, phenylalanine, glycine, alanine, tyrosine, lysine, histidine, arginine and leucine, are considered important, as these are an important part of the complex system regulating the biosynthesis of flavour-active compounds formed by yeast.<ref name="Ferreira"/> However, if supplementation is desired, a mixture of amino acids is more favorable to growth than when ammonium ions are the source of nitrogen.<ref name="Ferreira"/> Phenolic yeast may have a higher nitrogen requirement.<ref name="Ferreira"/> | Nitrogen is generally plentiful in wort and typically does not require supplementation for beer production.<ref name="Ferreira"/><ref name=jonesbudde>Jones BL, Budde AD. [https://www.sciencedirect.com/science/article/abs/pii/S0733521004001067 How various malt endoproteinase classes affect wort soluble protein levels.] ''J Cereal Sci.'' 2005;41(1):95–106.</ref> The concentration of the amino acids isoleucine, valine, phenylalanine, glycine, alanine, tyrosine, lysine, histidine, arginine and leucine, are considered important, as these are an important part of the complex system regulating the biosynthesis of flavour-active compounds formed by yeast.<ref name="Ferreira"/> However, if supplementation is desired, a mixture of amino acids is more favorable to growth than when ammonium ions are the source of nitrogen.<ref name="Ferreira"/> Phenolic yeast may have a higher nitrogen requirement.<ref name="Ferreira"/> | ||
Yeast consume at least 100-140ppm FAN in wort. Since proline cannot be utilized, wort has to contain 200-220ppm FAN. Inadequate nutrition can result in reduced yeast propagation and a delay in fermentation and maturation, and ultimately the retention of undesirable "young beer" off-flavors. Higher modified malts produce more FAN.<ref>Kunze, Wolfgang. "3.2 Mashing." ''Technology Brewing & Malting.'' Edited by Olaf Hendel, 6th English Edition ed., | Yeast consume at least 100-140ppm FAN in wort. Since proline cannot be utilized, wort has to contain 200-220ppm FAN. Inadequate nutrition can result in reduced yeast propagation and a delay in fermentation and maturation, and ultimately the retention of undesirable "young beer" off-flavors. Higher modified malts produce more FAN.<ref>Kunze, Wolfgang. "3.2 Mashing." ''Technology Brewing & Malting.'' Edited by Olaf Hendel, 6th English Edition ed., VBL Berlin, 2019, p. 230.</ref> If [[adjuncts]] are used, the brewer should consider using a protein rest (45-50°C) (see [[Mashing]]) or adding yeast nutrient. | ||
Worts that are prepared with reasonable percentages of malt tend to be rich in amino acids. Low FAN levels are undesirable in wort. The traditional rule is that serious problems (long lags, high diacetyl, etc) can result from FAN below 150-175ppm. A 12°P malt wort will typically have 225-275ppm FAN, which is ideal.<ref name=fix>Fix, George. ''Principles of Brewing Science.'' 2nd ed., Brewers Publications, 1999.</ref> As a general rule, it is usually desirable to keep FAN levels below 350ppm, something that can be achieved with a suitable [[mashing]] schedule. | Worts that are prepared with reasonable percentages of malt tend to be rich in amino acids. Low FAN levels are undesirable in wort. The traditional rule is that serious problems (long lags, high diacetyl, etc) can result from FAN below 150-175ppm. A 12°P malt wort will typically have 225-275ppm FAN, which is ideal.<ref name=fix>Fix, George. ''Principles of Brewing Science.'' 2nd ed., Brewers Publications, 1999.</ref> As a general rule, it is usually desirable to keep FAN levels below 350ppm, something that can be achieved with a suitable [[mashing]] schedule. | ||
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*https://www.brewersjournal.info/free-amino-nitrogen/ | *https://www.brewersjournal.info/free-amino-nitrogen/ | ||
Flavor compounds | ==Flavor compounds== | ||
During active biomass accumulation, H2S and ester production may occur. In this case, ester formation is stimulated by the presence of nitrogen, indicating that biosynthetic reactions are the source of these compounds. Once active growth has diminished and ethanol is accumulating, amino acid degradation occurs and, at this time, additional esters and fusel compounds may be produced. The fusel compounds come from the degradation of amino acids as nitrogen sources via the Ehrlich pathway.<ref name="Off">https://wineserver.ucdavis.edu/industry-info/enology/fermentation-management-guides/wine-fermentation/characters</ref> | During active biomass accumulation, H2S and ester production may occur. In this case, ester formation is stimulated by the presence of nitrogen, indicating that biosynthetic reactions are the source of these compounds. Once active growth has diminished and ethanol is accumulating, amino acid degradation occurs and, at this time, additional esters and fusel compounds may be produced. The fusel compounds come from the degradation of amino acids as nitrogen sources via the Ehrlich pathway.<ref name="Off">https://wineserver.ucdavis.edu/industry-info/enology/fermentation-management-guides/wine-fermentation/characters</ref> | ||
https://wineserver.ucdavis.edu/industry-info/enology/fermentation-management-guides/wine-fermentation/characters -- discussion of VSCs, esters, and aldehydes | https://wineserver.ucdavis.edu/industry-info/enology/fermentation-management-guides/wine-fermentation/characters -- discussion of VSCs, esters, and aldehydes | ||
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In many breweries producing South- | In many breweries producing South- | ||
ern German-style wheat beer, otherwise known as weissbier, after the installation of new cylindroconical fermentors, it is common for the beers to exhibit a noticeable decline in the bouquet characteristic of the style, which consists of primarily of compounds like isoamyl acetate (banana ester)[2]. The reason behind this somewhat diminished weissbier aroma is, among others, the high rate of yeast reproduction, which reduces the amount of the acetyl-coenzyme A available for ester formation. In addition, the high hydrostatic pressure in vertical vessels moderates the production of higher alcohols, thus reducing the numbers of reactants for the formation of esters. In short, the higher the liquid level is in a fermentation tank, the stronger the convection and homogenization, which results in a reduction in the formation of esters (fig. 4).<ref name=sacher2>Sacher B, Becker T, Narziss L. [http://www. | ern German-style wheat beer, otherwise known as weissbier, after the installation of new cylindroconical fermentors, it is common for the beers to exhibit a noticeable decline in the bouquet characteristic of the style, which consists of primarily of compounds like isoamyl acetate (banana ester)[2]. The reason behind this somewhat diminished weissbier aroma is, among others, the high rate of yeast reproduction, which reduces the amount of the acetyl-coenzyme A available for ester formation. In addition, the high hydrostatic pressure in vertical vessels moderates the production of higher alcohols, thus reducing the numbers of reactants for the formation of esters. In short, the higher the liquid level is in a fermentation tank, the stronger the convection and homogenization, which results in a reduction in the formation of esters (fig. 4).<ref name=sacher2>Sacher B, Becker T, Narziss L. [http://www.lowoxygenbrewing.com/wp-content/uploads/2017/04/pddvxvf.pdf Some reflections on mashing – Part 2.] ''Brauwelt International.'' 2016;6:392-397.</ref> | ||
The estery notes in beer have been observed to become more pronounced as the ratio of glucose to maltose tips in favor of glucose.<ref name=sacher2/> Alcoholic fermentation with yeast in the presence of high concentrations of glucose leads to a delay in the onset of maltose metabolism after an initial rapid decline in the extract content of the wort (similar to a "second lag phase"). This explains the plateau in the extract curve. During this time, the yeast are scarcely reproducing and are compensating with the synthesis of maltose permease and maltase. The diminished yeast reproduction results in overflow of the acetyl-CoA pool and thus greater ester formation and fruitier beers. | The estery notes in beer have been observed to become more pronounced as the ratio of glucose to maltose tips in favor of glucose.<ref name=sacher2/> Alcoholic fermentation with yeast in the presence of high concentrations of glucose leads to a delay in the onset of maltose metabolism after an initial rapid decline in the extract content of the wort (similar to a "second lag phase"). This explains the plateau in the extract curve. During this time, the yeast are scarcely reproducing and are compensating with the synthesis of maltose permease and maltase. The diminished yeast reproduction results in overflow of the acetyl-CoA pool and thus greater ester formation and fruitier beers. | ||
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This also comes into play when using [[adjuncts]] in brewing. | This also comes into play when using [[adjuncts]] in brewing. | ||
[[File:Flavor-compound-production.png | [[File:Flavor-compound-production.png]] | ||
In many Belgian-style specialty beers, POF+ S. cerevisiae strains are required to impart spice notes in the finished beer.<ref name=len>Lentz M. [https://www.mdpi.com/2311-5637/4/1/20 The impact of simple phenolic compounds on beer aroma and flavor.] ''Fermentation.'' 2018;4(1):20.</ref> There is a wide variety among these strains regarding POF activity. This at least partially explains the difference in volatile flavor compounds (phenolics and esters) produced by different strains such as those utilized for [[weissbier]] vs [[Belgian tripel]] styles for example. | In many Belgian-style specialty beers, POF+ S. cerevisiae strains are required to impart spice notes in the finished beer.<ref name=len>Lentz M. [https://www.mdpi.com/2311-5637/4/1/20 The impact of simple phenolic compounds on beer aroma and flavor.] ''Fermentation.'' 2018;4(1):20.</ref> There is a wide variety among these strains regarding POF activity. This at least partially explains the difference in volatile flavor compounds (phenolics and esters) produced by different strains such as those utilized for [[weissbier]] vs [[Belgian tripel]] styles for example. | ||
Only a few commercially available brewing yeast strains specifically list “peppery” as an expected descriptor for the finished beer. These include White Labs WLP565, Wyeast 3711, Wyeast 3726, BSI S-11, BSI S-26, and BSI 565. All of these strains are identified by the supplier as a most suitable for saison-style beers.<ref name=len/> | Only a few commercially available brewing yeast strains specifically list “peppery” as an expected descriptor for the finished beer. These include White Labs WLP565, Wyeast 3711, Wyeast 3726, BSI S-11, BSI S-26, and BSI 565. All of these strains are identified by the supplier as a most suitable for saison-style beers.<ref name=len/> | ||
See: | See: | ||
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*https://www.homebrewtalk.com/threads/be-256-dry-fermetis-abbey-has-anyone-used-it-results.670423/ | *https://www.homebrewtalk.com/threads/be-256-dry-fermetis-abbey-has-anyone-used-it-results.670423/ | ||
==Influence of water minerals== | |||
*https://www.brunwater.com/articles/brewing-water-and-yeast | *https://www.brunwater.com/articles/brewing-water-and-yeast | ||
==Harvesting== | |||
*[https://www.homebrewtalk.com/forum/threads/saving-yeast-at-the-starter-stage.676284/ Overbuild starters] | *[https://www.homebrewtalk.com/forum/threads/saving-yeast-at-the-starter-stage.676284/ Overbuild starters] | ||
*Drying kveik | *Drying kveik | ||
==Storage== | |||
*Under beer, jars vs vials | *Under beer, jars vs vials | ||
*Isotonic saline | *Isotonic saline | ||
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*https://www.themodernbrewhouse.com//forum/viewtopic.php?f=9&t=2074 | *https://www.themodernbrewhouse.com//forum/viewtopic.php?f=9&t=2074 | ||
==Articles to be reviewed== | |||
== Articles to be reviewed == | |||
*https://onlinelibrary.wiley.com/doi/pdf/10.1002/jib.242 | *https://onlinelibrary.wiley.com/doi/pdf/10.1002/jib.242 | ||
*https://onlinelibrary.wiley.com/doi/pdf/10.1002/j.2050-0416.2007.tb00259.x | *https://onlinelibrary.wiley.com/doi/pdf/10.1002/j.2050-0416.2007.tb00259.x | ||
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*Verbelen, P. J., and Delvaux, F. R. Brewing yeast in action: Beer fermentation. In: Applied Microbiology. M. K. Rai and P. D. Bridge, Eds. CAB International, Oxon, UK. Pp. 110-135, 2009. | *Verbelen, P. J., and Delvaux, F. R. Brewing yeast in action: Beer fermentation. In: Applied Microbiology. M. K. Rai and P. D. Bridge, Eds. CAB International, Oxon, UK. Pp. 110-135, 2009. | ||
*[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5620630/ Microorganisms in Fermented Apple Beverages: Current Knowledge and Future Directions] | *[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5620630/ Microorganisms in Fermented Apple Beverages: Current Knowledge and Future Directions] | ||
*[http://www. | *[http://www.lowoxygenbrewing.com/wp-content/uploads/2017/04/fischer_0606.pdf Effects of hydrostatic high pressure on microbiological and technological characteristics of beer] | ||
*http://www. | *http://www.lowoxygenbrewing.com/wp-content/uploads/2017/04/poeschl_0807.pdf The Influence of Fermentation-Control on the Colloidal Stability and the Reducing Power of the Resulting Bottom Fermented Beers | ||
*Krogerus, K. and Gibson, B.: A re-evaluation of diastatic Saccharomyces cerevisiae strains and their role in brewing. Applied Microbiology and Biotechnology, 104 (2020), pp. 3745-3756. | *Krogerus, K. and Gibson, B.: A re-evaluation of diastatic Saccharomyces cerevisiae strains and their role in brewing. Applied Microbiology and Biotechnology, 104 (2020), pp. 3745-3756. | ||
*https://www.biorxiv.org/content/10.1101/2020.06.26.166157v1.full | *https://www.biorxiv.org/content/10.1101/2020.06.26.166157v1.full | ||
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*Schwarz, K. J., Boitz, L. I., & Methner, F.-J. (2012a). Enzymatic formation of styrene during wheat beer fermentation is dependent on pitching rate and cinnamic acid content. Journal of the Institute of Brewing, 118(3), 280–284. | *Schwarz, K. J., Boitz, L. I., & Methner, F.-J. (2012a). Enzymatic formation of styrene during wheat beer fermentation is dependent on pitching rate and cinnamic acid content. Journal of the Institute of Brewing, 118(3), 280–284. | ||
*Gharwalova, L.; Sigler, K.; Dolezalova, J.; Masak, J.; Rezanka, T.; Kolouchova, I. Resveratrol suppresses ethanol stress in winery and bottom brewery yeast by affecting superoxide dismutase, lipid peroxidation and fatty acid profile. World J. Microbiol. Biotechnol. 2017, 33, 205. | *Gharwalova, L.; Sigler, K.; Dolezalova, J.; Masak, J.; Rezanka, T.; Kolouchova, I. Resveratrol suppresses ethanol stress in winery and bottom brewery yeast by affecting superoxide dismutase, lipid peroxidation and fatty acid profile. World J. Microbiol. Biotechnol. 2017, 33, 205. | ||
== References == | ==References== |