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The most basic method for making a mixed fermentation sour beer is to brew some simple wort (fresh extract or all grain) that is low in IBU's. Iso-alpha acids can inhibit many species and strains of LAB. Keeping the wort less than 6 IBU's is recommended in general, unless the brewer has information about their LAB culture that indicates that they can tolerate more. Mash hopping is one technique that can be used to limit the IBU's by about 70% <ref>[http://www.homebrewersassociation.org/attachments/presentations/pdf/2014/Putting%20Some%20Numbers%20on%20First%20Wort%20and%20Mash%20Hop%20additions.pdf Putting Some Numbers on First Wort and Mash Hop additions. David Curtis. NHC 2014.]</ref>. If hops are not required (commercial brewers may be required to use hops, while homebrewers aren't), they can be completely excluded from the recipe. The wort is often mashed at a high temperature to encourage the inclusion of complex carbohydrates in the final wort. The wort is then primary fermented with a ''Saccharomyces'' strain to achieve the majority of attenuation, leaving behind the complex carbohydrates. The primary fermentation is then inoculated with a mixed culture of ''Brettanomyces'', ''Lactobacillus'' and ''Pediococcus'', either by moving the wort into barrels with active cultures or by inoculating the primary fermentation vessel (i.e. glass carboy when the method is used by home brewers). This inoculation then starts a secondary fermentation of the remaining complex carbohydrates which follows a slow progression between the microbes that are primarily active. This secondary fermentation may not readily show apparent signs of active fermentation as in the primary fermentation but is often accompanied by the slow evolution of CO2 in the first 8 weeks and the eventual formation of a [[pellicle]] which may form quickly or very slowly depending on the presence of oxygen. This method is still the most commonly used by commercial producers of modern and traditional Belgian sour beer, with variations on the process occurring widely. While still widely used by homes brewers, fast fermentation methods such as [[Sour WortingWort Souring]] and other methods mentioned in this article are ever increasing in their use.

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'' ''(Pediococcu''s 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. See [[MTF Member Recipes]] for ideas on recipes, or the recipe sections of the books "American Sour Beers" by Michael Tonsmeire and "Wild Brews" by Jeff Sparrows.

Brewers have historically had concerns about aerating wort that has either been pre-soured with lactic acid bacteria (if the lactic acid bacteria is still alive) or if it 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 WortingWort Souring]]). These concerns, however, are largely unfounded. Most species of ''[[Lactobacillus]]'' are either not effected affected 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 in the presence of oxygen, however , in the presence of a healthy pitch of ''[[Saccharomyces]]'', which rapidly consumes the oxygen, this is probably also not a concern. Additionally, oxygen greatly improves the vitality and cell count of ''Brettanomyces'' and a small amount is required for effective ''Brettanomyces'' growth and fermentation (see [[Brettanomyces Propagation Experiment]]). 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, 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.

Once the wort is produced and chilled, the mixed culture can be pitched as normal. If using a mixed culture from a commercial yeast lab, a starter is generally not needed. If the culture is old or a larger volume is needed, generally a normal starter can be made for mixed cultures without fear of "throwing off the balance of microbes" (see [[Mixed_Cultures#Manufacturer_Tips|The Yeast Bay starter tips]] as an example; Bootleg Biology and Omega Yeast Labs also recommend starters for mixed cultures for larger batches <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1336235339738010/?comment_id=1336237029737841&comment_tracking=%7B%22tn%22%3A%22R%22%7D Discussion on MTF regarding mixed culture starters. 06/23/2016.]</ref>). Instead of buying a single mixed culture, a brewer can create their own mixed culture by combining their own ratios from single cultures of yeast and bacteria. A single mixed culture can be supplemented by adding pure cultures from different yeast labs as well. Another suggestion that often helps produce a higher quality sour beer is to supplement the mixed culture with a [[Commercial Sour Beer Inoculation]]. In general, the more diversity of microbes, the more complex a sour beer can potentially be. Using a [[Sour WortingWort Souring]] method in conjunction with this method can help increase acidity that may not otherwise be produced by some commercial blends (Wyeast Roeselare is known for this characteristic, for example).

# Pitch a pure culture of ''[[Lactobacillus]]'', and if possible hold the temperature between 90-120°F (32.3-48.9°C) for 2-4 days (see the [[Sour_WortingWort_Souring#Souring_in_the_Primary_Fermenter|Souring in the Primary Fermenter]] page for more details).

# For the last two months of aging, fruit, spices, and/or oak can be added directly into the fermenter (see [[Soured Fruit Beer]] and [[Soured_Herb,_Spice,_and_Vegetable_Beer|Soured Herb, Spice, and Vegetable Beer]]). Also , consider [[Blending]] with other sour beers.

* [[Sour WortingWort Souring]]