Old yeasts, young beer—The industrial relevance of yeast chronological life span

Abstract

Much like other living organisms, yeast cells have a limited life span, in terms of both the maximal length of time a cell can stay alive (chronological life span) and the maximal number of cell divisions it can undergo (replicative life span). Over the past years, intensive research revealed that the life span of yeast depends on both the genetic background of the cells and environmental factors. Specifically, the presence of stress factors, reactive oxygen species, and the availability of nutrients profoundly impact life span, and signaling cascades involved in the response to these factors, including the target of rapamycin (TOR) and cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) pathways, play a central role. Interestingly, yeast life span also has direct implications for its use in industrial processes. In beer brewing, for example, the inoculation of finished beer with live yeast cells, a process called "bottle conditioning" helps improve the product's shelf life by clearing undesirable carbonyl compounds such as furfural and 2-methylpropanal that cause staling. However, this effect depends on the reductive metabolism of living cells and is thus inherently limited by the cells' chronological life span. Here, we review the mechanisms underlying chronological life span in yeast. We also discuss how this insight connects to industrial observations and ultimately opens new routes towards superior industrial yeasts that can help improve a product's shelf life and thus contribute to a more sustainable industry.

Peculiarities of Growth Parameters of $Saccharomyces~cerevisiae$ Under Different Conditions

“…Ensuring robustness in performance during varying environmental conditions can be an important requirement in these processes [19]. In addition, the conditions during growth also influence subsequent survival [20]. For this reason, to achieve desired performance of a synthetic circuit outside laboratory-controlled environment, it is important to design temperature robustness.…”

Assessment of yeast physiology during industrial‐scale brewing practices using the redox‐sensitive dye resazurin

“…The development of staling flavors in beer are influenced by the production, packaging, and storage parameters (Vanderhaegen et al, 2006). Beer staling can be minimized using cooled transport and storage and reducing the presence of oxygen during brewing and bottling (Vanderhaegen et al, 2006; Wauters et al, 2021). Alternative measures to reduce beer ageing is bottle refermentation (or bottle conditioning).…”

“…Alternative measures to reduce beer ageing is bottle refermentation (or bottle conditioning). Bottle refermentation is a process that involves secondary fermentation through the addition of fermentable extract (priming sugar) and yeast to the bottle (Wauters et al, 2021). The practice of bottle refermentation is a traditional process used to naturally carbonate the beer, provide flavor stability, and potentially decelerate the aging process (Saison et al, 2010(Saison et al, , 2011.…”

HYPHAEdelity: a quantitative image analysis tool for assessing peripheral whole colony filamentation

“…Saccharomyces cerevisiae , an industrially relevant budding yeast, can undergo a reversible stress-responsive transition from individual ellipsoidal cells (yeast form) to filaments of thinly elongated cells (filamentous form) in response to nitrogen- or carbon starvation (Gimeno et al 1992 , Mösch and Fink 1997 , Lengeler et al 2000 , Mösch 2000 , Ceccato-Antonini and Sudbery 2004 , Etschmann and Schrader 2006 , Lodolo et al 2008 , Britton et al 2021 , Wauters et al 2021 ). This phenotypic switch allows microorganisms to undergo rapid microevolution to adapt to constantly changing microenvironments (Jain and Hasan 2018 ).…”