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Some brewers will harvest a certain amount of trub from their fermenters (500ml for example), and use only this amount to inoculate a new batch of beer. This will allow the brewer to control the amount of dead trub material that goes into the fresh beer. Michael Tonsmeire often advises that the brewer also pitch a fresh culture of Saccharomyces <ref>[http://www.themadfermentationist.com/2009/11/brewing-sour-beer-at-home.html Tonsmeire, Michael. The Mad Fermentationist. Brewing Sour Beer at Home. Comments section. Retrieved 2/19/2015.]</ref>.
Some brewers have good success reusing a yeast cake or a portion of a yeast cake by leaving the wort in contact with the old yeast cake for 3-4 days. After 3-4 days, a fresh culture of Saccharomyces is pitched to finish the fermentation. The 3-4 day head start gives the souring bacterias a head start and results in a low pH beer. The harvested yeast cake can also be pitched at the same time as a fresh culture of Saccharomyces, or afterwards. The decided timing on when to pitch the harvest sour yeast cake will effect the outcome of the sour beer. Early pitching of the sour yeast cake generally produces a more acidic beer, and later pitching generally produces a less acidic beer.
As with all methods, the species and strains of the microbes being used should always be taken into consideration. Experimentation and repeated processes should be carefully employed by the brewer in order to find the best results for their cultures. For example, using different strains of Saccharomyces cerevisiae as the primary fermenter can produce widely different results.