Protect
611
edits
Changes
→Pediococcus dominance
After the changing environment of the wort ends the growth of the enteric bacteria around 30 to 60 days, bacteria of the pediococcus come to dominate the bacterial flora. Lactobacillus can also be found in the wort in large numbers at this time, and both genuses are responsible for most of the [[Lactic acid|lactic acid]] in Lambic. Collectively these bacteria are known as the lactic acid bacteria.
The lactic acid bacteria increase in number until around month 7, achieving concentrations of 10⁴ 10<sup>4</sup> cells/mL wort, which is thought to coincide with the onset of summer and warmer temperatures.<ref name=Spitaels > F. Spitaels, A. D. Wieme, M. Janssens, M. Aerts, H.-M. Daniel, A. Van Landschoot, L. De Vuyst, P. Vandamme [http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0095384 | The Microbial Diversity of Traditional Spontaneously Fermented Lambic Beer], 2000</ref> With this in mind, it is thought that the increase in lactic acid bacteria be delayed or hastened by decreasing or increasing the storage temperatures, respectively.<ref name=Spitaels > F. Spitaels, A. D. Wieme, M. Janssens, M. Aerts, H.-M. Daniel, A. Van Landschoot, L. De Vuyst, P. Vandamme [http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0095384 | The Microbial Diversity of Traditional Spontaneously Fermented Lambic Beer], 2000</ref><ref name=AWAs>Nicholas A. Bokulich, Charles W. Bamforth, David A. Mills. [http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0035507|Brewhouse-Resident Microbiota Are Responsible for Multi-Stage Fermentation of American Coolship Ale], PLoS One, 7(4), 2012</ref>
Interestingly, lactic acid bacteria have been implicated in racemizing amino acids in beer, causing Lambic (and other beers which make use of lactic acid bacteria such as Berliner Wiesse) to have a high percentage of right-handed amino acid stereoisomers relative to both their starting materials and other beers.<ref name=Erbe >T. Erbe and H. Brückner, [http://www.sciencedirect.com/science/article/pii/S0021967300002557|Chromatographic determination of amino acid enantiomers in beers and raw materials used for their manufacture], 2000</ref>