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It is generally recommended to not re-use yeast that has fermented a soured wort. This has a stressful impact on the yeast. Some brewers have reported trying this, and not having good results <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/2119435291418007/?comment_id=2119664111395125&comment_tracking=%7B%22tn%22%3A%22R%22%7D Ryan Sandlin. Milk The Funk Facebook group thread on re-using kettle sour yeast. 06/06/2018.]</ref>. However, some [https://www.facebook.com/groups/MilkTheFunk/permalink/2017284411633096/ commercial brewers] have claimed that repitching WY3711 as many as 100 (in one case) to 2000 (in a second case) generations in soured wort conditions has not posed a problem for them. If this is attempted, repitching the yeast from the middle of the yeast cake will select for the more acid tolerant cells. Some yeast strains may not be able to adapt to these conditions as well as others (more data is needed), however, it has been shown that ''S. cerevisiae'' can adapt to acidic conditions and become more tolerant of low pH conditions from generation to generation. See [[Saccharomyces#Fermentation_Under_Low_pH_Conditions|terminal acid shock]] for more information.
Daniel LePage from Creature Comforts reported a "metallic" off-flavor from excess iron accumulation. The brewery found that yeast uptook most of the iron during fermentation and then released it over time. Removing as much of the yeast from the beer and as soon as possible resolved this issue. Creature Comforts resolved this by dumping the yeast from the bottom of the fermentation vessel daily for the first three days of yeast fermentation . They suspect that hte iron is coming from storing the ''Lactobacillus'' culture after souring in a keg before repitching it for the next batch (Creature Comforts has been repitching the same ''Lactobacillus'' culture for 6 years at the time of their World Brewing Congress presentation in 2020) <ref>[http://sites.libsyn.com/315398/episode-116-kettle-souring-w-daniel-lepage-from-creature-comforts Bru Lab Podcast Episode 116: Daniel LePage, Director of Quality at Creature Comforts in Athens, Georgia, joins Cade in the lab this week to chat about kettle souring.]</ref>(~40 mins in).See also the [https://www.masterbrewerspodcast.com/194 MBAA Podcast episode 194 interview with Daniel LePage.]
===Ropiness===