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first pass at aeration section
=== Wort Production===
The grain bill and production for the wort doesn't have to be complex, in fact many sour breweries produce their full line of sours from 2-3 base sour recipes which are then modified after aging by blending, the addition of fruit, dry hops or simply packaging them without alteration. For sour blonde ales, a simple grain bill of about 70% Pilsner malt and 30% malted wheat can be used (these can be replaced by Pilsner and wheat unhopped extracts for the extract brewer. See [http://byo.com/videos/item/975-lambic-brewing Lambic Brewing by Steve Piatz] or [http://www.homebrewtalk.com/showthread.php?t=322168 AmandaK's lambic-style extract recipe] for a good extract recipe). Some crystal and a small amount of roasted malts an be used for sour brown ales. Some higher chain sugars or even starches can be included for beers that will be aged for a long time and include Brettanomyces, or Brettanomyces and Pediococcus (Pediococcus generally should not be used without Brettanomyces. See the [[Pediococcus]] page for more details). Performing a [[Turbid Mash]] is the traditional way to include starches in the wort. However other methods such as steeping some oats or flaked wheat during the boil <ref>[http://www.homebrewtalk.com/f127/adjuncts-starches-sour-beer-448529/ Homebrewtalk Discussion started by Amos Brown aka 'Metic']</ref>, or running off over a bag of flaked oats or wheat on the way to the kettle can also impart starches that won't be converted to sugars by the mash (see [[Turbid_Mash#Alternative_methods_to_yield_starchy_wort|alternatives to turbid mashing]]). This step is completely optional, however it may be very beneficial to make sure some higher chain sugars or starches are available in the wort if the brewer wants to rely on Pediococcus for producing most of the acidity. Extract brewers can use 0.25 lbs. (0.11 kg) of Maltodextrin <ref>[http://byo.com/videos/item/975-lambic-brewing Lambic Brewing. Piatz, Steve. Brew Your Own Magazine. October, 2004.]</ref>, or hot steep a pound of flaked wheat, flaked oats, or carapils malt.
===Aeration===
(In progress)
Questions often arise regarding if and when wort aeration should be done. It is well documented that [[Saccharomyces]] uses oxygen to biosynthesize lipids, which include fatty acids and sterols, for their cell membranes. The cell membrane regulates the flow of nutrients into the cell and waste outside of the cell, and allows the yeast to reproduce. Each time a yeast cell doubles during growth, the parent cell gives approximately half of its lipids to the daughter cell. The more sugar available to the yeast, the more they will reproduce, and thus the more lipids they require. Thus, without a healthy cell membrane and a build up of lipids, the cell can die or produce weak daughter cells, potentially resulting in a range of off-flavors, especially in higher gravity beers <ref name="Aquilla">[https://www.morebeer.com/articles/how_yeast_use_oxygen "The Biochemistry of Yeast," by Tracy Aquilla. Morebeer Website. 07/25/2013. Retrieved 04/13/2016.]</ref><ref name="danstar">[http://www.danstaryeast.com/articles/aeration-and-starter-versus-wort Aeration And Starter Versus Wort. Danstar Website. Retrieved 04/13/2016.]</ref>. Therefore in the brewing of non-mixed fermentation beers, aerating both the yeast starter and the wort before pitching the yeast is generally considered mandatory to the brewing process.
Brewers have historically had concerns about aerating wort that has either been pre-soured with lactic acid bacteria (and is still alive) or will receive a co-pitch of lactic acid bacteria, ''[[Brettanomyces]]'', and ''[[Saccharomyces]]'' (see [[Mixed_Fermentation#Reusing_a_Sour_Yeast_Cake|Reusing a Sour Yeast Cake]], [[Mixed_Fermentation#Multi-Stage_Fermentation|Multi-Stage Fermentation]] and [[Sour Worting]]), however these concerns are largely unfounded. Most species of ''[[Lactobacillus]]'' are either not effected by oxygen, or benefit slightly ([[Butyric Acid]] production by ''Lactobacillus'' is not a concern; see [[Lactobacillus#Effects_of_Oxygen|''Lactobacillus'', effects of oxygen]] for details). Some species/strains of ''[[Pediococcus]]'' might be inhibited by oxygen, but not all (see ''[[Pediococcus#Growth_and_Environment|Pediococcus]]'' for details). ''[[Brettanomyces]]'' creates acetic acid from oxygen, however in the presence of a healthy pitch of ''[[Saccharomyces]]'', which rapidly consumes the oxygen, this is probably also not a concern. Thus, as long as a healthy pitch of ''[[Saccharomyces]]'' is present, aerating wort for mixed fermentation should lead to a healthy fermentation and good results.
Many brewers, however, do not aerate their wort when either pre-souring the wort with a pure culture of lactic acid bacteria, pitching fresh wort on top of a mixed culture yeast cake, co-pitching a mixed culture such as Wyeast Roeselare, East Coast Yeast Bug County, or pitching a custom mix of microbes from multiple sources <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1182597671768445/?qa_ref=qd Conversation on MTF about oxygenating wort for mixed culture fermentation. 11/22/2015.]</ref>. Many such brewers have reported success without aerating. We therefore recommend that the brewer investigate and experiment with their process in order to decide whether or not aeration is desired.
If the brewer is pitching a separate liquid culture of ''[[Saccharomyces]]'', it is recommended to create a starter on a stir plate and alternatively doze it with oxygen. This will allow the cell membranes to build enough lipids for their cells walls and give them the greatest chance of fermenting the wort without off-flavors <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1284106178284260/?comment_id=1284141108280767&comment_tracking=%7B%22tn%22%3A%22R3%22%7DConversation with Mark Trent on MTF regarding aerating starters/wort for mixed culture fermentations. 04/13/2016.]</ref>. Dried yeast is grown and processed in such a way that they contain enough lipids to support a healthy fermentation of 5% ABV or less without the need for aeration (this may be dependent on manufacturer; see the yeast manufacturer's website for their individual recommendations). Above 5% ABV however, and aeration should be considered <ref name="danstar"></ref>.
===Bug Inoculation===