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Liquid cultures become stressed by two factors: storage in an acidic environment, and storage without sugar <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1154970097864536/?comment_id=1156656834362529&offset=0&total_comments=12&comment_tracking=%7B%22tn%22%3A%22R%22%7D Conversation with Bryan of Sui Generis Blog on stress factors in storing Lacto. 09/28/2015.]</ref>. Sugar storage creates more acid as the ''Lactobacillus'' ferments it, so it may not be ideal unless the ''Lactobacillus'' is continually fed. Ideally for longer term storage, liquid cultures of ''Lactobacillus'' should be stored frozen with 20% glycerol, or refrigerated as slants with water or mineral oil. Also, there is anecdotal evidence that certain species may survive better at room temperature. Bryan hypothesizes that stable temperatures may be more important than storing at an "ideal" temperature <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1067614393266774/ Conversation with Bryan of Sui Generis Blog on Milk The Funk. 05/04/2015.]</ref>. For instructions on how to make slants at home capable of storing any microbe for potentially 2+ years, [http://suigenerisbrewing.blogspot.com/2015/11/easy-home-yeast-banking-and-video.html see Bryan video on Sui Generis Brewing (requires a pressure cooker)].
A practical option for brewers without a pressure cooker is to store the liquid culture with a few grams of a buffering chemical such as calcium carbonate (chalk), potassium phosphate, calcium sulfate (gypsum), or calcium hydroxide (pickling lime). The exact amounts should be adjusted to reach a pH of about 4.0-6.0 for the entire solution (begin with 1 or 2 grams per liter, and adjust as needed) <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1095449350483278/?comment_id=1095492120479001&offset=0&total_comments=23&comment_tracking=%7B%22tn%22%3A%22R6%22%7D Conversation with Adi Hastings on MTF. 6/20/2015.]</ref>.
Tom Belgrano offers these additional steps in order to remove the residual sugars from a storage solution, as well as raise the pH <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1154970097864536/?comment_id=1155560504472162&offset=0&total_comments=12&comment_tracking=%7B%22tn%22%3A%22R1%22%7D Conversation with Tom Belgrano on MTF regarding storing Lacto. 09/28/2015.]</ref>: