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== Commercially available Lactobacillus strains and their pH change over time ==
All data provided by [http://phdinbeer.com/2015/08/05/beer-microbiology-lactobacillus-ph-expeirment/ Matt Humbard]. Similar results were reported by Lance Shaner's [[Lactobacillus_Fermentation|100% Lactobacillus Fermentation]] experiment. See also the associated [https://byo.com/article/brewing-with-lactobacillus/ write up in BYO Magazine].
=== pH change at 86°F ===
====100% ''Lactobacillus'' Fermentation====
Lance Shaner's experiment on testing [[Lactobacillus_Fermentation|100% Lactobacillus Fermentation]] showed that '''pure cultures''' of WLP677, WLP672, Wyeast 5335, Wyeast 5223-PC, and the ''L. plantarum'' from Omega Yeast OYL-605, could not fully attenuate a 1.037 SG wort. The most attenuative ''Lactobacillus'' culture, WLP677, was only able to attenuate down to 1.03255 SG. It is likely that all species and strains of ''Lactobacillus'' available to brewers cannot fully attenuate wort. In addition, this study showed at most a 0.29% ABV in 100% ''Lactobacillus'' fermentations (attributed to WLP677). See [[Lactobacillus_Fermentation|100% Lactobacillus Fermentation]] for more information. If a higher attenuation is achieved, cross contamination of yeast is most likely the cause. Thomas Hübbe's masters thesis also supports that ''Lactobacillus'' attenuates less than 10% of the sugars in wort <ref name="Hubbe"></ref>.
The amount of CO2 produced is very small in heterofermentative species. Lance Shaner of Omega Yeast Labs noted that although ''L. brevis'' is classified as obligatory heterofermentative, the human eye cannot detect any CO2 production in the Omega Yeast Lactobacillus blend (OYL-605). Lance still needs to test this blend to see if it produces any CO2 at all. There have been reliable reports of pure ''Lactobacillus brevis'' cultures producing a layer of bubbles on the surface of wort if roused <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1354678291227048/?comment_id=1354678411227036&reply_comment_id=1355288821165995¬if_t=group_comment_reply¬if_id=1468974761019794# Conversation with Richard Preiss on MTF regarding pure Lactobacillus fermentation. 07/19/2016.]</ref>. It is clear though that any type of ''Lactobacillus'', regardless of whether it is heterofermentative or homofermentative, cannot produce a krausen. Krausens are sometimes seen even with the use of commercially available ''Lactobacillus'' cultures and good sanitation techniques. If a krausen develops in wort when it is the only culture that is pitched, this is indicative of cross-contamination of ''Saccharomyces'' or ''Brettanomyces'' in either the wort or the ''Lactobacillus'' culture itself <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1083842231643990/?comment_id=1084646124896934&offset=0&total_comments=26&comment_tracking=%7B%22tn%22%3A%22R8%22%7D Discussion with Lance Shaner on MTF. 6/7/2015.]</ref>. In addition to this, heterolactic fermentation by ''Lactobacillus'' can only produce 10-20% of the ethanol that Saccharomyces can produce <ref name="PhysioLacto">[http://phdinbeer.com/2015/04/13/physiology-of-flavors-in-beer-lactobacillus-species/ Humbard, Matt. Physiology of Flavors in Beer – Lactobacillus Species. Retrieved 6/14/2015.]</ref>, therefore a high level of attenuation cannot be achieved by ''Lactobacillus'' and is again a sign of cross contamination by yeast. Take a gravity reading and if the wort gravity has dropped more than 1°P (.004 specific gravity points) then this is due to a yeast fermentation.
An in-house experiment by Bell's Brewery which was presented at the MBAA Conference 2017 by Timothy Lozen reported slightly higher amoutns of ABV from a few species of ''Lactobacillus''. Out of 7 different species of ''Lactobacillus'' that were tested, ''L. bucherni'' (White Labs) produced the most alcohol at 0.64% ABV. ''L. rossiae'' (White Labs) and ''L. brevis'' (Bell's Brewery) produced around 0.4% ABV. ''L. delbruekii'' subsp. ''bulgaricus'' (ATCC #11842) produced around 0.5% ABV. The other strains, which were ''L. delbruekii'' subsp. ''lactis'' (ATCC #12315), ''L. casei'' (White Labs), and ''L. plantarum'' (Goodbelly) produced 0.1% or lower ABV <ref name="lozen_2017" />.
* See also [[Lactobacillus_Fermentation|100% Lactobacillus Fermentation]].
===Primary/Secondary Metabolites===