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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.

Yeast contamination is a concern when storing soured wort, especially in a sealed vessel such as a keg. Pure cultures of ''Lactobacillus'' cannot effectively ferment most sugars in wort (see [[Lactobacillus#100.25_Lactobacillus_Fermentation|100% ''Lactobacillus'' fermentation]]), therefore there are a lot of sugars available for contaminants to take advantage of when storing wort that has been soured but not fully fermented with yeast. Good sanitation practices are of the utmost importance. Equipment used should be thoroughly clean and ideally sterilized, or at least boiled if possible. If a yeast contamination goes unnoticed, then the keg can become heavily pressurized and potentially dangerous even when stored cold. We recommend regularly checking a keg of soured wort to ensure that over-pressurization does not occur, or use a spunding valve to ensure that over-pressurization does not occur. These methods only work with pure cultures of ''Lactobacillus'' (or at least cultures that do not contain an unwanted microbe that can take advantage of the residual sugars in the soured wort). Cultures from grains, [[Mixed_Cultures|mixed cultures]], or cultures from other fermented foods such as those listed on the [[Alternative Bacteria Sources]] wiki page, should be treated as a mixed culture. See [[Mixed_Fermentation#Storing_a_Yeast_Cake_or_Sample|Storing a yeast cake or sample of a mixed culture]].