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In Figure 2, the pH of the starter wort changed throughout the incubation period, with the aerobic and semi-aerobic treatments creating a lower pH from 24 hours to 72 hours. However, after 90 hours the pH for all treatments stabilized around the same pH (~3.4). Trent noted that although the pH of the final starters were nearly the same, the aerated condition tasted more acidic than the other three conditions <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1168024059892473/?comment_id=1168027756558770&reply_comment_id=1168031146558431&total_comments=8&comment_tracking=%7B%22tn%22%3A%22R9%22%7D Conversation with Mark Trent regarding his Brett experiment and sensory analysis. 10/23/2015.]</ref>.
This experiment demonstrated a significantly faster growth rate than many other growth rate studies <ref name="Yakobson">[http://www.brettanomycesproject.com/dissertation/propagation-and-batch-culture-growth/propagation-results/ The Brettanomyces Project. Propagation and Batch Culture Results. Retrieved 11/05/2015.] </ref>. It has been suggested by MTF member and microbiologist [http://www.escarpmentlabs.com/ Richard Preiss] that propagation times vary widely among ''Brett'' strains, and that the selected strain most likely exhibits faster reproduction than other strains <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1168024059892473/?comment_id=1168034189891460&offset=0&total_comments=20&comment_tracking=%7B%22tn%22%3A%22R4%22%7D Comments by Richard Preiss on MTF regarding Mark Trent's Brett growth experiment. 10/23/2015.]</ref>. Additionally, Trent's experiment did not demonstrate the same "second lag phase" as shown in Chad Yakobson's "The Brettanomyces Project" <ref name="Yakobson"></ref>, including for the lower cell count treatment in the second experiment. Richard Preiss hypothesizes that one possibility to explain this is that the cells had a two step growth process applied in preparation for the experiment, and that this prior exposure to wort allows the ''Brett'' cells to adapt their metabolism to malt sugars. Preiss reports seeing something similar when growing ''Brett''; : when first grown in YPD, then in ~50 mL of wort, the culture then grows to maximum cell density within 24-72 hours (depending on strain). Preiss also notes that not all strains of ''Brett'' exhibit the "second lag phase", and that the chosen ''Brett'' strain may be one of these strains <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1168024059892473/?comment_id=1168034189891460&reply_comment_id=1169578973070315&total_comments=2&comment_tracking=%7B%22tn%22%3A%22R9%22%7D Comments by Richard Preiss on MTF regarding Mark Trent's Brett growth experiment. 10/23/2015.]</ref>.
Oxygen levels between the four treatments were not measured with a Dissolved Oxygen meter. However, some observations were made by Trent that indicate a large difference in dissolved oxygen between the four treatments. The aerated (stir plate) treatment formed a significant vortex and the color (before growth) appeared milky due to the amount of agitation and perhaps gas dissolving into the media. Also a thick layer of foam was maintained on the aerated treatment throughout growth while only bubbles were observed on the semi-aerated <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1168024059892473/?comment_id=1168034189891460&reply_comment_id=1169576006403945&total_comments=2&comment_tracking=%7B%22tn%22%3A%22R9%22%7D Comments by Mark Trent on MTF. 10/26/2015.]</ref>.