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===Maintaining a Lactic Acid Bacteria Culture===
It is possible to maintain a pure culture ''Lactobacillus'' culture from batch to batch of beer. One method that is common with commercial brewers is to collect an appropriate volume of the soured wort (after souring, but before pitching yeast). Commercial brewers will often use a designated corny keg or sanke keg (depending on the volume that is required). After souring the wort a small portion will be transferred using a closed system into the keg. The keg is then refrigerated until it is needed for the next batch. Storing the soured wort cold is recommended for lengthening the viability of the ''Lactobacillus'' culture while also inhibiting the growth of any potential contaminants, however, the ''Lactobacillus'' might perform differently based on a number of variables such as how long it is stored (longer storage means less viability). Re-pitching might lead to an increase in acid production as well. We recommend experimenting with this process and finding the right pitching volume/storage time until repeatability can be achieved. For commercial brewers, Breakside Brewery recommends using 5-7% by volume of stored ''Lactobacillusbuchneri'' (WY5335) soured wort for a new batch, although this might vary based on many factors such as the strain of ''Lactobacillus buchneri'' (WY5335), the storage pH, and the storage time <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/2070392932988910/?comment_id=2070546129640257&comment_tracking=%7B%22tn%22%3A%22R%22%7D Neil Caron. Milk The Funk Facebook group thread on how much volume of stored soured wort to pitch for a new batch. 04/24/2018.]</ref>.
Homebrewers can use a similar process. For a 5 gallon batch of soured wort, collect around 1 liter of wort in a jar before pitching yeast. Keep the culture cold until the next use. Don't seal the jar completely tight in case refermentation occurs in the jar. If the culture is kept for more than a couple of months, then [[Lactobacillus#Starters_and_Pitching_Rate|create a 500 mL starter]] to ensure that the bacteria culture is still viable.