13,586
edits
Changes
no edit summary
Staggered pitching versus co-pitching can have a significant impact on the final flavor profile of the beer. While there is a lot of information regarding the fermentation profile of various microbes used in sour brewing, the impact of co-fermentation is less understood. Butler et al., partnered with Gilded Goat Brewing Company, analyzed the differences between co-pitching ''S. cerevisiae'', a strain of ''B. bruxellensis'', and a strain of ''L. plantarum'' (Sample A), versus pitching the ''S. cerevisiae'' and ''B. bruxellensis'' first and then the ''L. plantarum'' three days later (sample B), versus pitching the ''L. plantarum'' first and then the ''S. cerevisiae'' and ''B. bruxellensis'' three days later (Sample C). The three different beers were aged for a month and a half before packaged. Sample A was characterized as tasting the most balanced and consumers preferred it. Sample B was preferred the least and was characterized as having more "funk" flavor. Sample C had a distinctly sharp lactic sourness that overwhelmed the flavor from the ''Brettanomyces'', despite having slightly less lactic acid and a slightly lower titratable acidity than Sample A. Each of the three different fermentation profiles had a different sensory fingerprint with different measurements for proteins, titratable acidity (slight differences), lactic acid (slight differences), polyphenols, turbidity, color, and residual sugar, indicating that when individual species are introduced to ferment the wort, that it potentially has a wide impact on many different aspects of the beer. See the full poster [https://docs.wixstatic.com/ugd/695caf_8f98746d2f6942ff8810b298ef219eb9.pdf by Butler et al. here], as well as [https://www.facebook.com/groups/MilkTheFunk/permalink/2507876332573899/?comment_id=2507958592565673&reply_comment_id=2508072125887653&comment_tracking=%7B%22tn%22%3A%22R2%22%7D clarifications and corrections] to the "Conclusion" statements in the poster by Charlie Hoxmeier of Gilded Goat Brewing Company <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/2503719276322938/?comment_id=2503738896320976&comment_tracking=%7B%22tn%22%3A%22R%22%7D Kelley Freeman. Milk The Funk Facebook group post. 02/09/2019.]</ref>. These results may or may not be repeatable with different strains or other variables, but it does demonstrate that co-pitching and staggered pitching produce measurably different results.
Depending on the ethanol tolerance of the lactic acid bacteria strains present in the culture, the presence of ethanol can have a negative impact on lactic acid bacteria. For example, in one published study, at 11% ABV, the strain of ''L. brevis'' used in the study didn't grow as well than as in lower ABV samples, and the resulting lactic acid content was lower as well ion the 11% ABV beer <ref>[https://www.biorxiv.org/content/10.1101/2022.03.07.483260v1 Beer ethanol and iso-α-acid level affect microbial community establishment and beer chemistry throughout wood maturation of beer. Sofie Bossaert, Tin Kocijan, Valérie Winne, Johanna Schlich, Beatriz Herrera-Malaver, Kevin J. Verstrepen, Filip Van Opstaele, Gert De Rouck, Sam Crauwels, Bart Lievens. bioRxiv 2022.03.07.483260; doi: https://doi.org/10.1101/2022.03.07.483260.]</ref>. Therefore, adding the lactic acid bacteria earlier in the fermentation process versus later in higher ABV beers will most likely impact the final beer's lactic acid content.
See also: