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updated 100% ''Lactobacillus'' Fermentation with gluten reduction capabilities
A small number of strains of ''Lactobacillus'' can also break down polysaccharides and starches. They are referred to as "amylolytic LAB". They generally belong to the species ''Lb. manihotivorans'', ''L. fermentum'', ''L. amylovorus'', ''L. amylophilus'', ''L. plantarum'' or ''L. amylolyticus''. This seems to be associated with a gene called "amyA", which encodes for extracellular alpha-amylase activity, as well as alpha-glucosidase, neopullulanase, amylopectin phosphorylase, and maltose phosphorylase. This activity is limited by high amounts of glucose, maltose, or sucrose <ref name="peyer_review"></ref>. Some species can also produce beta-glucosidase capable of breaking down monoglycosides (see [[Glycosides]]), but not diglycosides. The activity of both alpha and beta-glucosidase enzymes are stable at low pH ranges of 3-4, are generally encouraged by increasing percentages of alcohol all the way up to 12% v/v, and are optimal at 35-45°C (depending on strain) <ref>[http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2672.2005.02707.x/full Screening of Lactobacillus spp. and Pediococcus spp. for glycosidase activities that are important in oenology. A. Grimaldi, E. Bartowsky, V. Jiranek. 2005. DOI: 10.1111/j.1365-2672.2005.02707.x.]</ref>.
====100% ''Lactobacillus '' Fermentation====
Lance Shaner's experiment on testing [[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 [[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>.
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Taubman et al. published a study in the MBAA Technical Quarterly that reported that a strain of ''L. brevis'', ''L. curvatus'', ''L. plantarum'', and ''Pediococcus pentosaceus'' that were found to reduce gluten in bread making had a similar functionality when fermenting wort. They found that these strains reduced gluten to undetectable levels in 5-7 weeks. However, they lost the ability to reduce gluten when co-fermented with yeast. The wort that was fermented with only one of the lactic acid bacteria strains and no yeast resulted in an unpleasant fermented beverage <ref>[https://www.mbaa.com/publications/tq/tqPastIssues/2018/Pages/TQ-55-1-0305-01.aspx Microbial Gluten Reduction in Beer Using Lactic Acid Bacteria and Standard Process Methods. Brett F. Taubman, Stephan Sommer, Jacob Edwards, Travis Laws, Logan Hamm, and Brenton A. Frank. 2018. DOI: https://doi.org/10.1094/TQ-55-1-0305-01.]</ref><ref>[http://masterbrewerspodcast.com/094-microbial-gluten-reduction-in-beer-using-lactic-acid-bacteria-and-standard-process-methods "094: Microbial Gluten Reduction in Beer Using Lactic Acid Bacteria and Standard Process Methods". Master Brewers Association Podcast. June 2018.]</ref>. The researchers hypothesized that the cause of the off-flavors in the 100% ''Lactobacillus'' fermentations were due to oxygen and hydrogen sulfide in the headspace of the fermenters, however, previous research has shown that wort fermented with only ''Lactobacillus'' does not fully attenuate which leaves ample amounts of residual sugar available for contaminants to potentially produce off-flavors (assuming they can withstand the low pH produced by the lactic acid bacteria fermentation). Performing long fermentations with only 'Lactobacillus'' are generally not recommended due to the residual sugar left by 100% ''Lactobacillus'' fermentation. For example, it is recommended to [[Wort_Souring#Souring_in_the_Boiler_.28Kettle_Sour.29|kettle sour]] within 24-48 hours in order to avoid off-flavor development. Attenuation/ethanol/final gravity measurements were not reported in this study.
* See also [[100% Lactobacillus Fermentation]].