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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 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> . Without a microscopeHowever, it is difficult to tell verify how much growth has occurredwith cheaper microscopes, so these rates may or may not be helpful to the brewer. Also,  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 a 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]]).
Starter mediums that brewers have used include unhopped DME wort starters and apple juice starters. These tend to be adequate for many brewers. However, [https://eurekabrewing.wordpress.com/2015/05/18/evaluate-starter-media-to-propagate-lactobacillus-sp/ Samuel Aeschlimann from Eureka Brewing Blog] showed that using DME with a little bit of apple juice, chalk, and yeast nutrients provides close to optimal cell densities that match MRS media cell densities.
# The starter should be held at the temperature best suited for the culture as shown in the [[Lactobacillus#Culture_Charts|Culture Charts]].
# Reference the above [[Lactobacillus#Culture_Charts|Culture Charts]] for how long the starter should be incubated for before pitching. If a stir plate is not used, one indication that the starter is done will be when the top of the starter begins to clear <ref name="Sam_starter2">[https://www.facebook.com/groups/MilkTheFunk/permalink/1131778916850321/?comment_id=1131806746847538&offset=0&total_comments=6&comment_tracking=%7B%22tn%22%3A%22R2%22%7D Conversation with Sam Aeschlimann of Eureka Brewing Blog on MTF. 08/20/2015.]</ref>.
# The chalk is not desirable to pitch into the beer because of its buffering effect. The chalk will sediment within hours of being added to the starter, or if a stir plate is used, a couple of hours after the stir plate is turned off <ref>[https://en.wikipedia.org/wiki/Stokes%27_law Stokes' law. Wikipedia. retrieved 09/24/2015.]</ref><ref name="Sam_starter2"></ref>. The ''Lacto'' should stay in suspension for at least a day or two after the starter is done, so swirling the starter isn't necessary, although it is certainly an option. If the starter is swirled, allow a couple of hours for the chalk to sediment out again. After the chalk sediments to the bottom of the flask, pour all of the liquid from the top of the starter into the wort/beer, and leave the chalk sediment behind. Avoid cold crashing the starter because it can have an adverse effect on the bacteria's health <refname="heit_lacto_starters">[http://suigenerisbrewing.blogspot.ca/2015/05/lacto-starters.html Heit, Bryan. Lacto Starters. Sui Generis Blog. Retrieved 6/15/2015.]</ref><ref name="sam_starter"></ref>.
See [http://suigenerisbrewing.blogspot.ca/2015/05/lacto-starters.html ''Lacto Starters'', by Bryan Heit of Sui Generis blog] for additional information on ''Lactobacillus'' starters.

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