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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 ''Lactobacillus'' in a wort-based starter media is recommended for building full pitches of ''Lactobacillus''. 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 ''Lactobacillus'' 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]]or MRS media), then pitching as little as 100-125 mL of fresh ''Lactobacillus'' 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>. 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>. 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 the brewer is confident that high growth rate has been achieved in the starter. Other factors that might affect the effectiveness of a volume based starter is the species/strain of the ''Lactobacillus'' being used, how much yeast contamination has occurred, and how old the ''Lactobacillus'' starter is. 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]]). If a ''Lactobacillus'' culture is older than 1 month, a fresh starter should be made. Keeping a separate Erlenmeyer flask for ''Lactobacillus'' starters can help to prevent yeast contamination <ref>Private correspondence with Richard Preiss to Dan Pixley. 11/20/2015.]</ref>.