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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 commercial 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 won'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''. We recommend using an Erlenmeyer flask dedicated to growing ''Lactobacillus'' in order to lower the potential for yeast contamination. We also recommend using [[Lactobacillus#Samuel_Aeschlimann.27s_Starter_Procedures|Samuel Aeschlimann's Starter Procedures]]. See [[Lactobacillus#External_Resources|External Resources]] for additional starter guides.
A good pitching rate for ''Lactobacillus'' is 100-125 billion cells per 5 gallons of wort, although pitching rates for ''Lactobacillus'' are more forgiving than they are for yeast. Having a manufacturer supply a cell count or doing a cell count manually after growth in a starter, and then pitching an exact cell count is the best approach to achieving the desired pitching rate. 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 of Sui Generis Blog. 5/6/2015.]</ref>. Pitching ~0.5-1 liter per ~20 liters of wort (~0.75-1 gallon per barrel) of ''Lactobacillus'' starter is the general guideline (see below). Note that the exact advisable starter volumes 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>, and their recommendations might differ from ours. Achieving exact pitching rates for ''Lactobacillus'' is generally not necessary because over-pitching does not have a negative impact, and under-pitching is also more forgiving than under-pitching yeast(under-pitching risks producing less acid than desired for some strains of ''Lactobacillus''). For these reasons, and the difficulty in estimating cell counts based on starter media type, strain, and other variables, a pitching calculator for ''Lactobacillus'' does not currently exist. However, estimations based on starter volume and freshness should be adequate.
The amount of growth that occurs in a starter is highly variable depending on the type of starter media, and the actual cell count is unknown unless the brewer can do a cell count. 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>. If the amount of growth cannot be accurately determined by cell counting under a microscope, then pitching 0.5-1 liter of fresh ''Lactobacillus'' starter culture per 5 gallons of wort ensures that an adequate number of cells will be pitched.