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This tends to create some fears for brewers who believe that the ''Saccharomyces'' strains in their beer might still be alive. However, in a highly acidic sour beer, ''Saccharomyces'' wine strains tend not to live for extended periods of time <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1268830686478476/?comment_id=1269605776400967&reply_comment_id=1270016239693254&comment_tracking=%7B%22tn%22%3A%22R%22%7D Conversation with Richard Preiss on MTF. 03/28/2016.]</ref>. Even if some cells do, their activity would be next to none due to no available sugars left in the beer (other than priming sugar), and thus their contribution to the flavor development of the beer would be minimal to none. Assuming good bottling practices are followed, fear of autolysis occurring due to killer strain activity is usually unfounded because most of the ''Saccharomyces'' cells are left behind with the trub at bottling. Additionally, ''Brettanomyces'' has the ability to metabolize the acids and proteins that are released during whatever autolysis that might occur in the bottle. Re-yeasting with wine yeast for priming has the additional advantage of not fermenting maltose or maltotriose, so unexpected attenuation from the wine yeast will generally not occur as long as the beer is already fully attenuated. Thus, there is little argument against re-yeasting with wine yeast at packaging time, other than a desire to approach carbonation in a traditional sense such as is the case with [[lambic]].
The flavor impact by the wine yeast in beers that contain living ''Brettanomyces'' is also probably minimal or not significant, although this has yet to be established scientifically <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1584074608287414/?comment_id=1584083038286571&reply_comment_id=1584163181611890&comment_tracking=%7B%22tn%22%3A%22R%22%7D Conversation with Richard Preiss on MTF. 02/15/2017.]</ref>. This would be due to the small amount of fermentables provided by the priming sugar, as well as the ability of ''Brettanomyces'' to metabolize many secondary metabolites that would be produced by a bottling yeast. It has been shown, however, that bottling yeast in general can have a flavor impact on clean beers without ''Brettanomyces''. For example one study found that out of 5 dried yeast strains from the Lallemand Yeast Culture Collection (Montreal, QC, Canada), one strain produced a higher final pH by about ~.05 (from 3.98 to 4.02 pH) in a Belgian dark ale (no ''Brettanomyces'' or other non-traditional microbes were used in the beer). The various strains tested also affected the levels of acetic acid, ethyl acetate, isoamyl alcohol, acetaldehyde, diacetyl, and glycerol in beer just from bottle conditioning <ref name="Zandycke_Bottling" />. Some brewers speculate that thiol esters (thioesters) thiols from wine yeast could also create novel characteristics in beer (although perhaps not from only bottle conditioning yeast) <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1380430375318506/ Conversation with James Sites about thiol producing wine strains on MTF. 08/19/2016.]</ref>. It could therefore be possible that metabolites produced from bottling yeast could have an effect on sour/"Brett" beer flavor as well, but this remains to be demonstrated scientifically.
* See [[Saccharomyces#Killer_Wine_Yeast|Killer Wine Yeast]] for more information.