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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.
Although more experiments and probably needed, agitation is believed to be an important factor for any species of microbe (yeast and bacteria). 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 <ref>[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 Heit about starters and agitation. 11/09/2015.]</ref>. Although ''Lactobacillus'' are aerotolerant and oxygen usually does not negatively affect their growth (except in hte the case of ''L. plantarum'', which has been shown to produce acetic acid when exposed to oxygen<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 seal the starter with an airlock.
=====Samuel Aeschlimann's Starter Procedures=====
# '''Facultatively heterofermentative''' Lactobacillus generally are homolactic when there is an abundance of carbohydrates, but can also perform heterolactic fermentation when carbohydrates are not abundant <ref name="Effects on Food Properties"></ref>.
Other factors can determine if a facultative heterofermentative species uses homolactic or heterolactic fermentation. For example, L. plantarum, which is a facultatively heterofermentative species, is homolactic without the presence of oxygen. In the presence of oxygen, however, it performs heterolactic fermentation, and produces acetic acid <refname="microbewiki_plantarum">[https://microbewiki.kenyon.edu/index.php/Lactobacillus_plantarum_and_its_biological_implications Lactobacillus plantarum and its biological implications. Microbe Wiki. Retrieved 6/7/2015.]</ref><ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1083842231643990/?comment_id=1084922688202611&offset=0&total_comments=28&comment_tracking=%7B%22tn%22%3A%22R%22%7D Conversation with Lance Shaner about L. plantarum on MTF. 6/7/2015.]</ref>.
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