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A: It would be great to translate the wiki into other languages, but the frequency of the changes to the wiki make this a difficult endeavor. Instead, we recommend using [httpshttp://translateitools.com/tool/google.com -translate-web-page-translator Google Translate]. Go to the Google Translate webpage, and paste in the wiki url on the left hand box (http://www.milkthefunk.com/wiki), and then select the language to translate the wiki to on the right hand side. Click "Translate", and then browse the wiki in the selected language.  ==Are there resources on judging sour beer?==Q: Are there are any resources to help me learn how to be a better beer judge for sour/wild beer styles? A: To get started being a better sour/wild beer judge, check out the [[Beer_Judging_Supplemental_Guide_-_Understanding_Flavors_and_Aromas_in_Sour_and_Mixed_Fermentation_Beer|Beer Judging Supplemental Guide]].

Q: My beer /starter/yeast slurry looks infected. What contaminated it and what do I do? A: Usually, contaminated beers do not give favorable results. Exceptions occur rarely from wild contamination. If the contamination was from a cultured ''Brettanomyces'' or some other yeast that came from not cleaning/sanitizing equipment well enough and that yeast/bacteria originated from a yeast lab, then the contaminated beer might turn out well or ok because cultures from yeast labs are selected for their positive results. Otherwise, the chances of wild contamination turning out good are very low. The best advice is to smell a sample of the beer, and if it does not smell good then dump the batch and brew a sour/funky beer on purpose (if the fermentation produces a fair amount of alcohol, it can be safely tasted after a month. See [[Wild_Yeast_Isolation#Safety|Safety]] for more information). If it smells good, the beer might be fine to package; however, even then your equipment will be exposed to the contaminating microbe(s) and there is no guarantee that the beer will continue to taste ok as it ages. Some contaminating microbes will slowly continue fermenting sugars in the beer and cause over-carbonation, bottle bombs, and increased off-flavors. So, the most pragmatic advice is to just dump it. If you choose to package the beer, keep the package cold so that the continued effects of the contamination are slowed as much as possible. Since the cost and time investments of a yeast starter/slurry are fairly low, it's best to just throw these out if they become infected and start over.  If you have space and time and want to simply learn what will happen with accidentally contaminated beer, then feel free to keep the beer in the fermenter and see how it evolves. Optionally, you could pitch Roeselare or some other [[Mixed_Cultures|mixed culture]] or [[Brettanomyces|Brett]] culture and see how it turns out after a few months. Brett can clean up some off flavors like diacetyl and acetaldehyde, but other off-flavors often won't be cleaned up by the Brett (like medicinal flavors and vomit/bile flavors). However, in the experience of most experienced sour beer brewers, this is not an efficient use of fermentation space. We recommend not wasting your time/fermentation space with accidental infections that show signs of off-flavors. Instead, use that space to brew an intentionally sour/funky beer and increase your chances of success.  As far as knowing what infected the beer based on what a pellicle looks like, the short answer is that [[Pellicle#Pellicle_Appearance_as_a_Microbe_Identifying_Indicator|you cannot confidently identify contaminating microbes based on what a pellicle or other visual signs look like to the naked eye]]. Microscopy can identify microbes to some degree (genus level), but DNA analysis is needed for species-level identification. See also information about [[Mold]]. (Please note that questions regarding accidental infections for beers that were intended to be clean beers are considered off-topic in the MTF Facebook group due to the number of these posts we would receive otherwise.) ==How do I catch wild yeast and/or bacteria==Q: How do I catch wild yeast or bacteria? A: There are a few methods for catching wild yeast and bacteria. Some of the advanced methods involve using agar to isolate individual colonies of yeast or bacteria, but less advanced methods can also be successful although these methods will usually contain mixed cultures of wild microbes. Read the [[Wild Yeast Isolation]] wiki page for more information. Q: Can I set out a glass of beer or wine to catch wild yeast or bacteria to use to make sour beer or wine?

A: Usually contaminated beers do not give favorable resultsYou can, but this method doesn't work very well unless you intend to make vinegar with the microbes that you catch this way. Exceptions occur rarely from wild contamination. If the contamination was from a cultured ''Brettanomyces'' Wild yeast that originated from equipment that was used is desirable for purposeful mixed fermentations, then the contaminated brewing doesn't generally grow very well in finished beer might turn out wellor wine. Otherwise, the chances of a wild contamination turning out good are very The alcohol and low. The best advice is to smell pH prevent a sample lot of the microbes from growing in beer, and if it does not smell good then dump the batch and brew a sour/funky wine. Lactic acid bacteria generally don't grow well in finished beer or wine either unless they are already adapted to grow in beer on purpose or wine (if see the fermentation produces a fair amount of alcohol, it can be safely tasted after a month. See [[Wild_Yeast_Isolation#Safety|SafetyQuality Assurance]] for more informationwiki page). If When you have the space and time and want to simply learn what will happen with accidentally contaminated leave a glass of beer, then feel free to keep or wine out in the beer open for a few days and see what happens. Optionally, you could pitch Roeselare or some other a layer of microbes begins growing on top forming a [[Mixed_Cultures|mixed culturePellicle]], these microbes are acetic acid bacteria such as [https://en.wikipedia.org/wiki/Acetobacter ''Acetobacter''] or [[Brettanomyces|Bretthttps://en.wikipedia.org/wiki/Gluconobacter ''Gluconobacter'']] culture and see how it turns out. Another option if the beer still tastes fine and you don't want to risk additional off-flavors would be to pasteurize the beer at 140°F for 15 minutes (this These microbes grow in alcoholic beverages when oxygen is the standard time also present and temperature for pasteurization of beer in use the brewing industry because it kills efficiently ethanol as a food source while damaging the beer less than boiling temperaturesexcreting acetic acid (vinegar)as a waste product. However, in the experience of most experienced sour beer brewers, this is not an efficient use of fermentation space This can be a [https://www.popsci. We recommend not wasting your timecom/diy/article/2008-12/fermentation space with accidental infections that show signs of offmaking-vinegar-flavors. Insteadhome/ good way to make vinegar], use but not a good way to catch microbes that space to brew an intentionally sour/funky will taste good when fermenting out wort or must since acetic acid and acetic acid bacteria such as ''Acetobacter'' and ''Gluconobacter'' are not desireable for beer and increase your chances of successwine fermentation. As far as knowing what infected Read the beer based on what a pellicle looks like, the short answer is that [[Pellicle#Pellicle_Appearance_as_a_Microbe_Identifying_Indicator|you cannot identify contaminating microbes based on what a pellicle looks likeWild Yeast Isolation]]wiki page for more information on how to have better success at catching wild yeast or lactic acid bacteria.

A: There are many different opinions on this, but we will state here the best balance between practical and cautious advice. [[Brettanomyces |''Brettanomyces'']] can be cleaned and sanitized just like regular yeast, and if a brewery is using a saison yeast known for causing contamination issues like [[Saccharomyces#Diastatic_strains_of_Saccharomyces_cerevisiae|diastatic strains of ''Saccharomyces cerevisiae'']] without contaminating other beers, then they will probably be successful using other wild yeast as well. Bacteria such as ''Pediococcus '' and ''Lactobacillus'' can be a little hardier, but they also still die from intense cleaning and sanitizing. Maintain a very good cleaning and sanitizing regimenregiment, and if you can, use heat treatment of 140°F+ for 30 or 45 minutes. If you can do this, you shouldn't need different fermenting vessels if they are glass or , stainless steel, or kegging equipment. Plastic is prone to microscopic scratchesand often can't withstand heat treatment, which can help bacteria survive cleaning/sanitizing regiments, so separate plastic fermenters for beers that have bacteria ([[Lactobacillus|''Lactobacillus '']] or [[Pediococcus|''Pediococcus'']]) in them should be considered, but may not be necessary. Since cold side plastic equipment such as auto siphons and hosing are cheap, it is recommended to go ahead and get separate plastic racking equipment, airlocks, bungs, keg tap tubing lines, etc. Equipment that can be boiled can be re-used for clean and sour beers.

See [https://www.facebook.com/groups/MilkTheFunk/permalink/1710242802337260/ this MTF thread[Mixed_Fermentation#Quality_Assurance_and_Avoiding_Cross_Contamination|Quality Assurance and Avoiding Cross Contamination]] for advice on brewing sours and clean beers together in a commercial brewery, as well as chapter 2, "Sanitation and safety" in "American Sour Beers" by Michael Tonesmeire. You can also make a [[Wort_Souring|Kettle Sour]] to avoid risking cold side equipment getting contaminated.

A: First off, killer wine strains only kill susceptible ''S. cerevisiae''. They do not kill ''Brettanomyces''. Secondly, if the commercial beer is sour then the chances of the wine yeast still being alive are slim. Anecdotally, brewers have had great success with dregs from breweries who bottle wine yeast (for example dregs from Hill Farmstead). See the [[Commercial_Sour_Beer_Dregs_Inoculation#The_Dreaded_Killer_Champagne.2FWine_Yeast|Champagne Yeast in Commercial Dregs]] and [[Packaging#Re-yeasting|Packaging and Re-yeasting]] page for more details on killer wine yeast strains.

A: The biggest factor leading to lack of souring while using lacto Lacto is due to the amount of hops in your recipe. Even as much as 2-3 ibuIBU's will inhibit lactic acid production. Try brewing or kettle souring with no hops. See [[Sour WortingWort Souring]] for more information. For mixed fermentation sour beer, sometimes it will become sourer given enough time, but if you used less than 30 IBU of hops then you can try adding more commercial dregs from different sour beer producers (see [[Commercial Sour Beer Dregs Inoculation]]). If you used too many hops in the recipe, then the beer may never sour. Q: I tried to make a kettle sour, but it didn't sour. A: This can happen for a few reasons. Common mistakes are: using ''Lactobacillus delbruekii'' from White Labs, using hops, and souring at too warm of a temperature. read the [[Wort Souring]] wiki page for a full set of instructions on kettle souring.

A: Sometimes Roeselare and other mixed cultures don't get the acidity that you might want. If it hasn't been a year yet, waiting longer may help, but sometimes it doesn't. If after a year the acidity is not high enough for you, try adding fruit such as cherries or raspberries (or even fresh wort). The fruit has various acids in it, and the sugar content will partially be turned into lactic acid by the surviving bacteria (the brewer's yeast will be dead after a year). Another option is to brew another beer and design it to be more sour. Brewing with no hops 0-5 IBU and a very high mash temperature (158°F-160°F) is highly recommended for next time. Also, don't ferment with a clean yeast first and then add Roeselare in secondary; use Roeselare as the primary fermenter. Make sure the Roeselare package is fresh and was properly stored at refrigeration temperatures (lactic acid producing bacteria can die quickly if not stored right). Keep in mind that beer with some acid in it will taste sourer once you carbonate and chill it. For more information, see [[Mixed_Cultures#Wyeast|Roeselare]] and [[Mixed Fermentation]].

Q: I am not am not an all grain brewer, can I brew sour beer with extract?

A: It depends on the off-flavor. Typical yeast character such as moderate amounts of diacetyl, banana, clove, and other esters will often be changed by Brett. However, many other flavors from things like fusel alcohols will not. Brett can esterify a small amount of [[Isovaleric Acid]] and [[Butyric Acid]], but if the beer has high amounts of these then they are likely to stay. As the old saying goes, garbage in, garbage out. It's better to brew a clean beer and then add Brett, rather than try to recover a badly brewed beer by adding Brett.

A: Brett only makes a beer "funky" and fruity. It does not produce a lot of acidity. You need to brew a beer using a lactic acid bacteria such as [[Lactobacillus]] or [[Pediococcus]]. Check out the [[Sour WortingWort Souring]] and [[Mixed Fermentation]] pages.

Q: I used probiotics and my beer didn't sorrysour. What happened?

A: It depends on your species of ''Lactobacillus''. For example, ''L. plantarum'' (both the Omega Labs OYL-605 Lacto blend and plantarum probiotics) tends to prefer 70-95°F, and temperatures of 110°F+ can kill it. Check out our recommendations on the [[Lactobacillus#Culture_Charts|Lacto Culture Chart]], [[Alternative Bacteria Sources]], and the [[Sour WortingWort Souring]] pages. ==I have a question about kettle souring==Q: How do I get started with kettle souring? A: Check out our wiki page on [[Wort_Souring#Souring_in_the_Boiler_.28Kettle_Sour.29|kettle souring]] and our [https://www.milkthefunk.live/podcast/2018/4/2/episode-004-kettle-souring-with-adi-hastings-from-omega-yeast-labs podcast with Adi Hastings from Omega Yeast labs on kettle souring.]. Q: I used some hops and it didn't sour. Why? A: Most lactobacilli are inhibited by small amounts of hops. This is especially true if the species is ''Lactobacillus plantarum''. As a general rule of thumb, NEVER add any hops until after the souring has been done.  Q: How do I kettle sour, why did my kettle sour turn out bad, or is this mold? A: There is a lot of poor information on the internet regarding kettle souring. We recommend starting with reading our [[Wort_Souring#Souring_in_the_Boiler_.28Kettle_Sour.29|detailed guide to kettle souring]]. We also recommend listening to our step by step instructions in our [https://www.milkthefunk.live/podcast/2018/4/2/episode-004-kettle-souring-with-adi-hastings-from-omega-yeast-labs podcast interview with Adi Hastings from Omega Yeast labs]. In general, here are our biggest tips:# Don't use WLP677 for kettle souring, it's very slow and not meant for quick souring.# Don't use any hops until after the souring has finished. Even 1 IBU will inhibit a lot of Lacto strains.# Try to keep the souring time within 48 hours. Lacto leaves a lot of residual sugars, so the longer it is left the more potential there is for off-flavors from contaminations. # Sanitation is very important. Make sure the wort is boiled for at least a minute, and the sides of the boil kettle and lid are pasteurized/sanitized. Despite popular belief from many commercial brewers, using CO² is not necessary.# For your first kettle sours, we recommend using a ''Lactobacillus plantarum'' culture of some sort. For commercial cultures from yeast labs, see the [[Lactobacillus#Culture_Charts|''Lactobacillus'' culture charts]]. For example, the [https://omegayeast.com/yeast/bacterial-cultures/lactobacillus-blend Omega Yeast Labs OYL-605] has had a lot of success among MTF'ers. Yogurt and probiotics have also become a popular source for fast souring Lacto; see [[Alternative Bacteria Sources]].# If your wort develops a krausen or significant CO² production, then you probably have a yeast contamination. Lacto does not compete well with yeast, so the sourness might not be as much as you wanted. Sloppy sanitation practices can lead to yeast contaminations, but this has also been known to come from yeast lab products themselves (it's hard to prove the exact source of the yeast contamination unless you look at the Lacto culture under a microscope using [http://suigenerisbrewing.com/index.php/2014/08/07/your-home-yeast-made-easy-aseptic-techniques/ aseptic techniques]). See [[Wort_Souring#Dealing_With_Yeast_Contamination|Yeast Contamination in Kettle Souring]] for more information.# Mold looks like patches of often fuzzy/hairy, off-white, green, red, or black growths on the surface of your beer. This can happen with kettle sours if your sanitation is not good enough. We recommend dumping kettle sours that have significant mold growth. See the [[Mold]] page for more details on the risks of mold.# If you can't find the answers to your questions from these resources, feel free to ask your question in the MTF Facebook group.

A: Conventional wisdom is to remove the beer from the trub as soon as the beer is done fermenting, but this is not needed with beers that contain ''Brettanomyces'' yeast. Brett can "consume" the proteins and fatty acids that are released by dying yeast cells. Many brewers have reported storing sour beer on trub for many months and even multiple years without experiencing off-flavors from yeast autolysis. Read the [[Mixed_Fermentation#Secondary_Fermentation|Mixed Fermentation]] page for more details.

A: It Yes, but keep in mind that sometimes it is difficult to preserve the exact character of a blend, as the ratio of organisms will vary over time. Try repitching and see how you like the results. Pitching a fresh pitch of [[Saccharomyces]] yeast is a good idea. Read [[Mixed_Fermentation#Reusing_a_Sour_Yeast_Cake|this wiki page]] for more information.

Q. My mixed culture from <nowiki>[X]</nowiki> yeast lab expired. Can I make a starter with it or use it? A. Yes, make a starter with it. If the starter shows signs of fermentation, then the mixed culture can be used in a full batch of beer. Signs of fermentation include a drop in pH, gravity, or if those measurements are not possible, bubbles/CO² production and turbidity (cloudiness). If a full krausen does not form, then pitch an additional fresh package of brewer's yeast (a Belgian or saison strain is a good choice, but any strain will suffice). Mixed culture starters should go for about 7 days. See [[Mixed_Cultures#Starters_and_Other_Manufacturer_Tips|Mixed Culture Starters]] for more details. ==When is the beer ready or when can I bottle/blend==Q: My When will my beer be ready, or my beer is at 1.XXX---can I bottle /keg it? Can I blend it? A: For first time sour beer brewers, no one can tell you when your beer will be ready; this is determined on a case by case basis due to the many variables involved. Only you can determine this. Despite internet rumors, sour or mixed/Brett fermentation beers don't always end up at or below 1.000 final gravity (some can end up quite a few points above that depending on the microbe selection and the wort composition). There is also no set time frame when the beer will be ready to package. The best guide is a long-term stable gravity: if your gravity has remained stable between several readings, then your beer may be ready for packaging. However, since the different organisms involved in sour beer production grow at different rates, a beer that was stable over a short period may begin fermenting again. Ideally, you should look for stable gravity readings over a period of two months.  When blending (especially with a non-sour beer such as a clean Saison), it is best to rest the blend in a fermenter for two months to make sure the gravity is stable. Don't assume that a low gravity clean beer, such as a very dry Saison, won't further attenuate once blended with a sour beer with Brett in it.  If kegging, packaging after most of the wort has fermented but before the final gravity is reached is ok since kegs can hold the additional pressure, and the carbonation can be adjusted. Using a [https://byo.com/project/build-your-own-spunding-valve-to-carbonate-in-the-keg/ spunding valve] with a keg can help achieve the desired carbonation.

A: The best guide other factor to consider is long term stability: if your how does the beer taste? If it tastes good, and the gravity has remained is stable between several readings, then your beer may be ready for packagingyou can package it. However, since If the different organisms involved in sour beer production grow at different rates, does not seem to have a beer mature flavor from the ''Brettanomyces'' and has off-flavors that was stable over a short period may begin fermenting again. Ideallyneed to age out, you should look for stable gravity readings over a period of two monthsthen feel free to age it longer. When blending Some off-flavors will change even when bottled or kegged, but others (especially with a non-sour beer such as a clean Saisonsulfur-based compounds), it is best will need to rest dissipate out of the blend in a fermenter for two months to make sure the gravity is stable. Don't assume that a low gravity clean beer such as a very dry Saison won't further attenuate once blended with a sour beer with Brett in it. If kegging instead of bottling, packaging before the final gravity is reached is ok since kegs can hold the additional pressure, and the carbonation can be adjusted. See the [[Packaging]] page for details on how to package your beerslowly over time.

The other factor See the [[Packaging]] page for details on how to consider is how does the beer taste? If it tastes good, and the gravity is stable, then you can package it. If the beer does not seem to have a mature flavor from the ''Brettanomyces'' and has off-flavors that need to age out, then feel free to age it longer. Some off-flavors will change even when bottled or kegged, but others (such as sulfur) will need to dissipate out of the your beer slowly over time.

A: Check out our [https://www.zeemaps.com/map?group=2744749 MTF Member Map]! Matt Miller also maintains a map for just this purpose! . [http://sourbeerblog.com/sour-beer-map/ Click here] to check it out. Contact Matt There are also other beer groups on Facebook or on the map page to have a place added!and BeerAdvocate for getting recommendations.

A: We recommend against using shallow plastic tubs as coolships. Most plastics are not food grade. And those that are may not be food grade at boiling temperatures. Also, boil kettles provide suffficient sufficient cooling rates as long as outdoor temperatures are cold enough. If you are looking to mimic commercial processes, then a homebrew-sized boil kettle has a surface area:to volume ratio more similar to commercial coolships and will have a cooling rate more comparable to commercial producers. See the [[coolship]] page for more info.

We have two great pages that help you brew your first kettle sour. See the [[Sour WortingWort Souring]] page, and the [[Lactobacillus#Culture_Charts|Lacto Culture Charts]]!

A: Food darkens in two ways: enzymatically with oxygen and phenols, or from maillard reactions from cooking. Darkening can occur from scorching the wort during wort production, or from using malt extract (which is darker from oxidation, or from production of the extract). If the darkening is not from the hot side wort production, then the browning was caused by oxidation in the fermentation vessel. Check out this [https://en.wikipedia.org/wiki/Browning_(food_process) Wikipedia page on food browning] for an overview of enzymatic browningand [[Aging_and_Storage#General_Effects_of_Oxidation|Effects of Oxidation]].