Changes

''Yeast autolysis'' is the rupturing of dead yeast cells, and produces meaty or rubbery off flavors <ref>[http://byo.com/kegging/item/182-beat-yeast-bite Freccia, Nico. Beat Yeast Bite. Brew Your Own Magazine. April 1997. Retrieved 2/20/2015.]</ref>. When it comes to sour beers, Lambic producers often let their beers age in barrels on the trub for up to four years without effects of off flavors from yeast autolysis. The theory hypothesis is that the ''[[Brettanomyces]] '' will metabolize the off -flavor compounds produced by the bursting ''[[Saccharomyces]] '' cells, and use them as nutrients <ref>[http://www.themadfermentationist.com/2013/05/second-pull-wine-barrel-solera.html Tonsmeire, Michael. Second Pull Wine Barrel Solera. The Mad Fermentationist Blog. Retrieved 2/20/2015.]</ref>. Therefore, many people have reported that they have successfully avoided yeast autolysis in ''solera'' projects, as well as just allowing sour beer to remain in the primary fermenter for the entirety of it's its aging. However, as the ''solera'' ages, trub build up buildup can eventually potentially become be a problemfor logistic reasons (such as clogging ports). Will Meyers of Cambridge Brewing Company reported an eventual autolysis issue with his solera <ref>[http://www.themadfermentationist.com/2013/05/second-pull-wine-barrel-solera.html Tonsmeire, Michael. Second Pull Wine Barrel Solera. The Mad Fermentationist Blog. Comments section, July 30, 2014 at 9:39 PM. Retrieved 2/20/2015.]</ref>.

Whether or not the brewer elects to refill the ''solera'' with wort or fresh beer can also potentially play a role in yeast autolysis issues eventually creeping up in a ''solera''. Adding wort will create a thicker trub, which could lead to autolysis issues faster. In either case, theoretically , these issues can be avoided. One method for avoiding off flavors from yeast autolysis is to rack some of the trub out of the solera when the seasonal pulls are taken. Another method is to rack the ''solera'' to another vessel once a year or every other year. Once removed from the trub, the ''Brettanomyces '' should be able to clean up the off flavors over time.