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# 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, 1.5-2-20 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 growth 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]].