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→Samuel Aeschlimann's Starter Procedures
# Reference the above [[Lactobacillus#Culture_Charts|Culture Charts]] for how long the starter should be incubated for before pitching (24-48 hours is a general rule of thumb). 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 (turbidity is an indication that the culture is growing, and once the top portion of the starter starts to clear then that is a sign that growth has stopped) <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 ''Lactobacillus'' 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 <ref name="bryan_lacto_starters">[http://suigenerisbrewing.blogspot.ca/2015/05/lacto-starters.html "Lacto Starters." Bryan from Sui Generis Blog. Retrieved 6/15/2015.]</ref><ref name="sam_starter"></ref>.
======Notes On Safety======
It is well documented that many pathogens can grow in wort when the pH is above 4.5 and ethanol is not present or very low. While it may be possible for pathogens to grow in the environment created by adding chalk to the starter, the chances of this are very low. There are a few reasons for this low risk. Firstly, typical brewing sanitation regimes and the use of commercial pure cultures of ''Lactobacillus'' should prevent unwanted microbes from contaminating the starter media. Additional steps can be taken with [[Quality Assurance|quality assurance]] to ensure the purity of the starter. Secondly, once the starter is added to wort and the wort drops below a pH of 4.6, any contaminating microbes will be killed. In the case of [[Wort_Souring#Souring_in_the_Boiler_.28Kettle_Sour.29|kettle souring]], any contaminating pathogens will be killed during the second boiling step. Finally, yeast fermentation will ensure that pathogens are not able to survive once the pH levels drop below 4.6 and ethanol is produced. For example, a similar pattern of pathogenic bacteria being killed by yeast growth and/or lactic acid bacteria growth can be seen in [[Spontaneous_Fermentation#Microbial_Succession_During_Fermentation|spontaneous fermentation]] where enteric bacteria are often inherently present during the early stages of fermentation, but are quickly killed as the pH drops and ethanol levels rise.
Storing the growth media with a pH above 4.5 for more than 3-4 days could result in a very small risk of botulism growth. Therefore, if the starter is going to be stored anaerobically for more than a few days, a target pH under 4.6 should be achieved to prevent the growth of botulism or other pathogenic contaminants. For more information on the general risks of pathogens in beer/wort/starters, see the [[Wild_Yeast_Isolation#Safety|Wild Yeast Isolation Safety wiki page]], the [[Mold|Mold wiki page]], [https://suigenerisbrewing.com/index.php/2017/01/05/fact-of-fiction-can-pathogens-survive-in-beer-the-rdwhahb-edition/ this Sui Generis Blog post], and [https://beerandwinejournal.com/botulism/ this article on the small risk of botulism in wort that is stored for more than a few days by Chris Colby].
======Modified Versions======
* [http://suigenerisbrewing.blogspot.ca/2015/05/lacto-starters.html ''Lacto Starters'', by Bryan of Sui Generis blog] for additional information on ''Lactobacillus'' starters.
* For media for growing from stocks, see [[Laboratory_Techniques#Lactobacillus.2FPediococcus|Laboratory Techniques]].
====Cell Growth====