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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 new beer. Michael Tonsmeire often advises that the brewer also pitches 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>.
In general, it is advised to pitch a fresh culture of ''Saccharomyces'' to ferment the bulk of the wort sugars. This can be done before adding the sour yeast cake, or at the same time. 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 1-4 days before pitching a fresh culture of ''Saccharomyces''. After 1-4 days, a fresh culture of ''Saccharomyces'' is then pitched to finish the fermentation. The 1-4 day head start gives the souring bacteria a head start and results in a low pH beer. The decided timing on when to pitch the harvest sour yeast cake will affect the acidity 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. It might also be possible to not pitch any fresh yeast and rely completely on the sour yeast cake to fully attenuate the wort. In this case, it might take 3-10 days for the fermentation to begin because this approach would be relying on the ''Brettanomyces'' that is alive in the yeast cake, and the growth phase of ''Brettanomyces'' can take a week or so. If relying only on the sour yeast cake to fully attenuate the wort, making a starter for the yeast cake is preferable to ensure that the microbes in the yeast cake are viable. A [[Pellicle|pellicle]] might also develope early, depending on what types of microbes are in the yeast cake and if they have a tendency to develop pellicles or not. Oxygenate as normal whenever the ''Saccharomyces'' is pitched to ensure a healthy ''Saccharomyces'' fermentation (''Brettanomyces'' also benefits from small amounts of oxygen, and oxygen does not greatly effect lactic acid bacteria; see [[Mixed_Fermentation#Aeration|Aeration]] above).
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 could produce widely different results, and the use of 10-30 IBU's in the wort can be used to inhibit the lactic acid bacteria if they become too strong and produce too much acidity.