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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. See [[Lactobacillus#Samuel_Aeschlimann.27s_Starter_Procedures|Samuel Aeschlimann's Starter Procedures]]. Specific nutrients that will increase growth is thiamine (vitamin B1), or a combination of thiamine and riboflavin (vitamin B2). For example, it has been shown that thiamine is required in order for ''L. brevis'' to efficiently convert pyruvate into lactic acid and ethanol. The addition of these nutrients can help encourage growth <ref>[http://onlinelibrary.wiley.com/doi/10.1002/jib.385/full The influence of thiamine and riboflavin on various spoilage microorganisms commonly found in beer. Barry Hucker, Melinda Christophersen, Frank Vriesekoop. 2017.]</ref>.
Although more experiments and probably needed, agitation is believed to be an important factor for both yeast and bacteria in general. Gentle stirring on a stir plate or orbital shaker, or frequent gentle manual agitation leads to faster growth and a higher number of organisms. Agitation keeps the microbes in solution. It also maximizes the microbes' access to nutrients and disperses waste evenly. In a non-agitated starter, the microbes are limited to the diffusion rate of nutrients, leading to a slower and more stressful growth <refname="bryan_agitation">[https://www.facebook.com/groups/MilkTheFunk/permalink/1168024059892473/?comment_id=1174865305875015&reply_comment_id=1176092372418975&total_comments=1&comment_tracking=%7B%22tn%22%3A%22R9%22%7D Conversation with Bryan of Sui Generis Blog about starters and agitation. 11/09/2015.]</ref>. If agitation is not possible for whatever reason, a successful starter can be made without agitation. Sam Aeschlimann reported good success with ''Lactobacillus'' starters that are not agitated <ref name="Sam_starter2"></ref>.
Although ''Lactobacillus'' are tolerant of oxygen and oxygen usually does not negatively affect their growth (except in the case of ''L. plantarum'', which has been shown to produce small amounts of acetic acid when exposed to oxygen and glucose is not present <ref name="Quatravaux_plantarum">[http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2672.2006.02955.x/full Examination of Lactobacillus plantarum lactate metabolism side effects in relation to the modulation of aeration parameters. S. Quatravaux, F. Remize, E. Bryckaert, D. Colavizza, J. Guzzo. 2006]</ref><ref name="microbewiki_plantarum"></ref>), it is also generally not needed (an exception to this may be ''L. brevis'', which has been shown to increase growth rates in the presence of oxygen <ref name="brevis_aeration"></ref>). Therefore, it is generally best practice to prevent aerating the starter with an airlock for ''Lactobacillus'' starters. If exposure to air occurs, and the starter does not smell like it has been contaminated by the exposure, then the starter can still be used.
# Add 100 grams of DME to around 900 mL of water and heat pasteurize/boil as you would normally do for a starter. This should make 1.040 SG (10°P) starter wort.
# Cool the DME wort to the desired incubation temperature (see step 4), and add 100 mL of pasteurized apple juice, 20 grams of chalk (CaCO3), and half a teaspoon of yeast nutrients. The chalk won't dissolve into solution, so don't worry about it. <ref name="sam_starter">[https://eurekabrewing.wordpress.com/2015/05/18/evaluate-starter-media-to-propagate-lactobacillus-sp/ Evaluate starter media to propagate Lactobacillus sp., Eureka Brewing Blog, by Samuel Aeschlimann.]</ref>. Boiling the apple juice might destroy some of the nutrients in the apple juice that assist ''Lactobacillus'' in its growth, and since it is pasteurized boiling it is not necessary <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1152787381416141/?comment_id=1153930734635139&reply_comment_id=1153949097966636&total_comments=4&comment_tracking=%7B%22tn%22%3A%22R6%22%7D Conversation with Samuel Aeschlimann and Jason Pappas on MTF about the effects of boiling apple juice. 09/24/2015.]</ref>.
# Best practice is that starters should not be aerated, although there may be an exception to this for ''L. brevis'' <ref name="brevis_aeration"></ref>. Some people prefer to stir their starter with an airlock in order to keep the bacteria in suspension, others do not use a stir plate and keep the starter still. Agitation might improve grwoth rates by dispersing waste and nutrients equally <ref name="bryan_agitation" />. One advantage to not using a stir plate at least until the brewer is more familiar with their culture is that the top of the starter will begin to clear when the starter is done if the starter was kept still.
# 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 (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>.