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changed all occurences of the word "bugs" to "microbes" or something else with more dignity
====Secondary Fermentation====
After primary fermentation the mostly attenuated beer is moved to a secondary fermentation vessel. Often in traditional commercial production secondary fermentation is conducted in wine barrels, however home brewers can accomplish this phase in glass or plastic carboys with low oxygen permeability. A mixed culture of ''Brettanomyces'', ''Lactobacillus'' and ''Pediococcus'' is then introduced to the beer. If barrels are being used then these "bugs" microbes may simply come from the walls of the barrel, originating from a previous batch. Alternatively, the brewer might inoculate the wort with a mixed culture directly, either with a house culture or by introducing the dregs of bottled sour beer. Upon their introduction these new microorganisms begin converting the longer chain sugars left over from the primary fermentation. These sugars are primarily converted into alcohol and lactic acid, increasing the degree of attenuation and lowering the pH of the beer. This also corresponds with a decrease in ''S. cerevisiae'' cell counts, and the release of amino acids and vitamins from yeast autolysis might help fuel lactic acid bacteria and ''Brettanomyces'' <ref name="Hubbe">[https://www.facebook.com/groups/MilkTheFunk/1407620505932826/ Effect of mixed cultures on microbiological development in Berliner Weisse (master thesis). Thomas Hübbe. 2016.]</ref>. Other flavor impacting secondary metabolites are also produced, depending on the strains used. In the presence of oxygen, acetic acid is also produced which in low amounts can be complementary, adding to the complexity of the beer.
Some brewers (mostly homebrewers) do not find it necessary to move the mostly attenuated beer into a secondary vessel. Instead, the mixed culture is pitched directly into the primary fermenter. While yeast autolysis is a concern in regular brewing, it is not a cause for concern in mixed fermentations that contain ''Brettanomyces''. Lambic brewers, for example, perform a primary fermentation in barrels, and leave the beer in the barrels during the beer's entire aging process, which is usually 1-3 years <ref>[http://www.lambic.info/Brewing_Lambic#Barrels Lambic.info Wiki. Brewing Lambic. Retrieved 6/8/2015.]</ref>. Yeast autolysis releases trehelose, acids, and other compounds, which are metabolized by ''Brettanomyces'' <ref>[http://www.mbaa.com/districts/michigan/events/Documents/2011_01_14BrettanomycesBrewing.pdf Brettanomyces in Brewing the horse the goat and the barnyard. Chad Yakobson. 1/14/2011.]</ref>. Maintaining a [[Solera]] may be an exception to this (see the [[Solera]] page for details). The advantage of not moving the beer into a secondary vessel is that less overall oxygen is introduced into the beer (oxygen exposure will contribute to more acetic acid and then ethyl acetate production), and may be the best option if the brewer does not have a closed/CO2 system to prevent exposure to oxygen during transferring.
3) Pitch plenty of yeast. I'd use a culture with lots of healthy ''Saccharomyces'' and lots of ''Brettanomyces'', and maybe bacteria, right at the start of primary. This lets ''Brettanomyces'' character develop more quickly and helps you hit a stable gravity quicker. I always do this, and there are ''Brettanomyces'' aromas coming out of the airlock almost immediately. If you reuse this culture, you'll start selecting for things that get the job done quickly.
4) Pitch your culture low, but then let it rip, and warm it up a bit towards the end of fermentation, if necessary. That should get most of the sugars fermented pretty fast but without the off flavours you can get from pitching hot. Brettanomyces can often clear those up, but it takes time. The less mistakes you leave for your bugs yeast/bacteria to clear up, the sooner it will be ready.
5) Bottle as soon as you hit a stable gravity. If you do it right, your final gravity should be 0.998-1.002 pretty quick. If you bottle soon, I find you don't get any [[Tetrahydropyridine|THP]] (presumably because there's enough healthy ''Saccharomyces'' around to ferment the priming sugar without producing it). It was only when I decided I wanted my beer to be a bit clearer, and so started leaving it in primary until it cleared, that I started regularly seeing small amounts of THP developing early in bottle conditioning.