Changes

The pH of boiling wort influences how well proteins are precipitated out, with a pH of about 5.2 being ideal for this mechanism. At a lower pH, these proteins gain negative charges, and at a higher pH they gain positive charges, making them resistant to settling out during boiling. Boiling a low pH wort that has been acidified with the fermentation of ''Lactobacillus'', therefore does not effectively precipitate out haze forming proteins. However , haze forming polyphenols, which are also required for haze formation, are greatly reduced by an unknown mechanism during kettle souring, which potentially leads to good clarity in the final beer <ref name="Peyer_2017" />.

Maillard and various browning reactions lead to darkening of beer in general. These reactions are both temperature and pH related. A low pH will actually prevent these reactions, and results in a quantitatively lighter color beer compared to a control beer that is not acidified <ref name="Peyer_2017" />. ===Oxygen===There is no basis for the idea that small amounts of oxygen that could get dissolved during wort souring has a great effect on ''Lactobacillus''. See [[Lactobacillus#Effects_of_Oxygen|Effects of Oxygen on ''Lactobacillus'']] and [https://www.facebook.com/groups/MilkTheFunk/permalink/1778865588808314/ this MTF thread] that discusses the anecdotal experience of brewers who do not purge with CO2. The effects of oxygen on the beer could lead to other stability issues with the beer because oxygen during wort production can play a role in beer staling (see [[Aging and Storage]]). Some brewers believe that purging all oxygen out of the system will help to prevent aerobic contaminates from creating [[Isovaleric_Acid#Kettle_Souring|isobutyric acid]]. Oxygen does not play a role in the production of [[Butyric Acid]] in wort soured beers because this compound is produced by anaerobic bacteria (bacteria that requires the absence of oxygen). Follow the links in this paragraph for more information.