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Lactobacillus

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In addition to the starter information given in the [[Lactobacillus#Manufacturer_Tips|Manufacturer Tips]] above, this section includes general advice for ''Lactobacillus'' starters for homebrewers and brewers. For growing ''Lactobacillus'' in a lab environment, or from an initial grouping of cells from a plate/slant or smaller cell count, MRS media is the most efficient growth media. However, for full pitches of ''Lactobacillus'' in beer/wort, brewers probably don't want to add that much MRS media to their beer since MRS media has a distinct odor and smell that would not be desirable in beer <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1152135114814701/?comment_id=1152674674760745&offset=0&total_comments=9&comment_tracking=%7B%22tn%22%3A%22R0%22%7DConversation with Lance Shaner and Nick Impellitteri on Lacto starters on MTF. 09/22/2015.]</ref>. Therefore, growing ''Lacto'' in a wort-based starter media is recommended for building full pitches of ''Lacto''. See [[Lactobacillus#External_Resources|External Resources]] for additional starter guides.
Pitching ~0.5-1 liter per ~20 liters of wort (~0.75-1 gallon per barrel) of ''Lactobacillus'' starter is the general guideline. The exact advisable pitching rates of commercial cultures may differ from manufacture to manufacturer. <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1077639885597558/ MTF thread started by Brad Primozic. 5/29/2015.]</ref>. Counting cells and pitching an exact cell count is the best approach. However, counting cells of ''Lacto'' under a microscope can be difficult to achieve due to the small size of bacteria cells, so starter volumes are generally used instead when talking about pitching rates for ''Lactobacillus'' <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1068323126529234/?comment_id=1068337639861116&offset=0&total_comments=47&comment_tracking=%7B%22tn%22%3A%22R9%22%7D Conversation on MTF with Bryan Heit. 5/6/2015.]</ref>. Matt Miller of Sour Beer Blog and Richard Preiss of Escarpment Yeast Labs advise that if ideal growth (1-2 billion cells/mL) can be achieved (for example by using [[Lactobacillus#Samuel_Aeschlimann.27s_Starter_Procedures|Samuel Aeschlimann's starter procedure]]), then pitching as little as 100-125 mL of fresh ''Lacto'' starter for 5 gallons of beer can achieve desirable acidity within 24 hours <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1180630378631841/?comment_id=1180733761954836&reply_comment_id=1180740128620866&comment_tracking=%7B%22tn%22%3A%22R9%22%7D Conversation with Richard Preiss on MTF regarding Lacto starters. 11/19/2015.]</ref><ref name="sbb2.0"></ref>. Average Moderately ideal growth in a starter results in around 500 million cells/mL, resulting in a 400 mL starter for 5 gallons, and low growth results in around 100 million cells/mL, resulting in a 2 liter starter for 5 gallons, according to Matt Miller (see [http://sourbeerblog.com/lactobacillus-2-0-advanced-techniques-for-fast-souring-beer/ Matt Miller's article] for more details) <ref name="sbb2.0"></ref> . However, it is difficult to verify how much growth has occurred with cheaper microscopes, so these rates may or may not be helpful to the brewer.
Another thing to consider is that achieving a pH of 4 as fast as possible is advisable for preventing off-flavors from other microbes <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1180630378631841/?comment_id=1181674265194119&reply_comment_id=1181715048523374&comment_tracking=%7B%22tn%22%3A%22R7%22%7D Conversation with Bryan Heit on MTF regarding speed of acid production with Lacto. 11/20/2015.]</ref>. Larger pitch rates tend to achieve a lower pH faster <ref name="heit_lacto_starters"></ref>. Achieving a desirable low pH (3.5, for example) as fast as possible might also help with head retention. Therefore, unless using [[Lactobacillus#Samuel_Aeschlimann.27s_Starter_Procedures|Samuel Aeschlimann's starter procedure]], pitching 0.5-1 liters of starter for 5 gallons of wort is advisable in general. Even when using [[Lactobacillus#Samuel_Aeschlimann.27s_Starter_Procedures|Samuel Aeschlimann's starter procedure]], over-pitching ''Lactobacillus'' is not a concern (pitching an overly massive starter wort could produce undesirable flavors), so the same pitch rate should still be considered unless. Other factors that might affect the effectiveness of a volume based starter is the species/strain of the ''Lacto'' being used, and how much yeast contamination has occurred. Some species/strains may require a larger volume of starter, as well as if yeast has contaminated the starter or wort (see [[Lactobacillus#100.25_Lactobacillus_Fermentation|100% Lactobacillus Fermentation]]).

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