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Review
. 2024 Feb 19:15:1346724.
doi: 10.3389/fmicb.2024.1346724. eCollection 2024.

The two faces of microorganisms in traditional brewing and the implications for no- and low-alcohol beers

Giulia E Roselli  1 , Daniel W M Kerruish  2 , Matthew Crow  3 , Katherine A Smart  3 , Chris D Powell  1
Affiliations
Review

The two faces of microorganisms in traditional brewing and the implications for no- and low-alcohol beers

Giulia E Roselli et al. Front Microbiol. .

Abstract

The production of alcoholic beverages is intrinsically linked to microbial activity. This is because microbes such as yeast are associated with the production of ethanol and key sensorial compounds that produce desirable qualities in fermented products. However, the brewing industry and other related sectors face a step-change in practice, primarily due to the growth in sales of no- and low-alcohol (NoLo) alternatives to traditional alcoholic products. Here we review the involvement of microbes across the brewing process, including both their positive contributions and their negative (spoilage) effects. We also discuss the opportunities for exploiting microbes for NoLo beer production, as well as the spoilage risks associated with these products. For the latter, we highlight differences in composition and process conditions between traditional and NoLo beers and discuss how these may impact the microbial ecosystem of each product stream in relation to microbiological stability and final beer quality.

Keywords: bacteria; beer quality; contamination; microbiological spoilage; yeast.

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Conflict of interest statement

DK, MC, and KS were employed by Diageo PLC. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figures

Figure 1
Figure 1
A simplified overview of the key metabolic products generated by yeast strains during fermentation. Note that the extent and ratio of compounds are often interlinked and dependent on factors such as the nutritional content of the wort, the nutritional requirements of the yeast strain, as well as factors influencing yeast growth such as inoculation rate and the amount of oxygen available. Note also that in some yeast species certain pathways may be used preferentially, while others may be absent. For example, for Brettanomyces yeast strains, the ability to produce glycerol is limited and the production of phenolic compounds is greatly elevated when compared to Saccharomyces yeasts. Created with Biorender.com.
Figure 2
Figure 2
Microbiological points of risk typically observed in the brewing process. Potential sources of microbial contamination are indicated by the warning symbols. Created with Biorender.com.
Figure 3
Figure 3
Environmental and physiochemical factors associated with the brewing process that may influence the risk of microbial spoilage. The changes that occur in un/fermentable sugars, oxygen, nutritional content [including free amino nitrogen (FAN) vitamins and minerals], carbonation, ethanol content and pH are represented. Boiling and pasteurisation (when used) represent key stages where microbial loading is reduced. Note that additional factors such as microbial adaptation to stress should be considered, while effective sanitation and correct storage temperatures are relevant across the brewing process. These latter should be controlled where possible, otherwise risk can be exacerbated accordingly. Created with Biorender.com.
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References

    1. Adams M. R., O'Brien P. J., Taylor G. T. (1989). Effect of the ethanol content of beer on the heat resistance of a spoilage Lactobacillus. J. Appl. Bacteriol. 66, 491–495. doi: 10.1111/j.1365-2672.1989.tb04569.x - DOI
    1. Amaha M., Kitabatake K. (1981). “Gushing in beer” in Ed. Pollock, J.R.A. Brewing science (London: Academic Press; ), 457–489.
    1. Anderson R. J., Howard G. A. (1974). Production of hydrogen Sulphide by yeast and by Zymomonas anaerobia. J. Inst. Brew. 80, 245–251. doi: 10.1002/j.2050-0416.1974.tb03613.x - DOI
    1. Back W. (1981). Beer spoilage Bacteria. Taxonomy of beer spoilage Bacteria. Gram Positive Species. Monatsschr Brauwiss. 34, 267–276.
    1. Back W. (1987). Nachweis Und Identifizierung Von Fremdhefen in Der Brauerei. Brauwelt Int. 127, 735–737.

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