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==Short Boils and Raw Ale==
[http://www.garshol.priv.no/blog/331.html [Raw Ale|Raw ale]], also referred to as "no-boil", is a method of wort production that involves not boiling the wort, or perhaps by some definitions, very short boils <ref name="larsblog">[http://www.garshol.priv.no/blog/331.html Raw ale. Lars Marius Garshol. Larsblog. 06/05/2016. Retrieved 03/02/2016.]</ref>. Although mainly a historical method of brewing, this style of brewing has recently become popular in the production of [[Berliner Weissbier]] and other styles of beer using [[Wort_Souring|wort souring or kettle souring]] methods. Many recipes for these styles of beer call for pilsner malts to be used, which can contain higher amounts of SMM precursor. An often asked question about no-boil/raw ales and wort boiled for 15 minutes or less is: are there concerns about DMS production?
Anecdotal reports of no issues with DMS in these types of beers seem to far outweigh the reports of DMS problems <ref>[http://brulosophy.com/2015/10/08/update-lab-data-on-pils-malt-boil-length-exbeeriment/ "Update: Lab Data on Pils Malt Boil Length Exbeeriment" on Brulosophy. Retrieved 03/08/2016.]</ref><ref>[http://beerandwinejournal.com/30-min-boil/ "All Grain Pale Ale 30-Minute Boil Experiments" by James Spencer on Beer & Wine Journal. 06/24/2015. Retrieved 03/08/2016.]</ref><ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1243791188982426/ Discussion on MTF regarding DMS in raw ale/no boil/short boils. 03/01/2016.]</ref><ref name="larsblog"></ref>. The specific nature of (or lack of) DMS detection in no-boil/raw ale has not been widely explored by science. There are, however, some explanations that have been proposed. For example, when boiling smaller volumes of wort such as on the homebrew scale there is a larger surface area to volume ratio. This larger surface area to volume ratio allows for more evaporation and volatilization of DMS to occur <ref name="beersmith">[https://www.youtube.com/watch?v=YDBKUCkg8cM Boiling Home Brewed Beer with Dr Charlie Bamforth - BeerSmith Podcast #121.]</ref> (~30 minutes in). Smaller fermenters would also benefit from a larger surface area to volume ratio since CO2 from fermentation volatilize DMS. This may account for the general lack of DMS reported in homebrewed and small-scale farmhouse beer.
Commercial brewers performing no-boil beers have also often reported a lack of DMS issues in their beer <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1367101639984713/ Poll to commercial brewers on MTF on getting DMS in no-boil beers. 08/04/2016.]</ref><ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1243791188982426/?comment_id=1251233804904831&reply_comment_id=1251348394893372&comment_tracking=%7B%22tn%22%3A%22R9%22%7D Conversation with Jeff Crane fro mCouncil from Council Brewing Co on no-boil and DMS. 03/12/2016.]</ref>. There are likely other factors at play that limit the amount of DMS produced. Specifically, the conversion of SMM to DMS happens extremely slowly at temperatures under 95°C, which would result in less DMS being produced during no-boil brewing. DMS is also very volatile in the temperature range of 50-100°C. See [[Dimethyl_Sulfide#Volatility_of_DMS|DMS Volatility]] and [[Dimethyl_Sulfide#DMS_Prediction_Models|DMS Prediction Models]] for more information on why DMS is probably not an issue with no-boil beers.
In sour beer, there might be other compounds that make the detection of DMS more difficult. For example, 2-phenylethanol and phenethyl acetate mask the perception of DMS in beer <ref name="bamforth"></ref>. Additionally, some tasters might be genetically predisposed to perceive the flavor of DMS more easily than others.
===Considerations for Historical Examples of Raw Ale===
In the case of [[Raw Ale|raw ale]], and particularly [http://www.garshol.priv.no/blog/331.html Norwegian/Latvian/Lithuanian traditional farmhouse ales, Finish "sahti", and Estonian "koduõlu"], there is some debate as to whether or not DMS should always be considered an off-flavor. Traditionally these beers were made with lightly kilned malts that were malted by the brewers themselves (up until about 20 years ago), and these malts may have had high levels of SMM precursor. [http://www.garshol.priv.no/blog/304.html Lars Marius Garshol offers his philosophy] on off-flavors in beer in general, which is inspired by writings of Michael Jackson, and makes an argument that DMS may have been considered desirable or acceptable in farmhouse raw ales brewed in certain regions of Europe, especially considering that the flavor of DMS is desirable in other foods <ref>Private correspondence with Lars Marius Garshol by Dan Pixley regarding whether DMS should be considered an off-flavor in farmhouse raw ales. 03/10/2016.</ref>.
Additionally, it has been suggested that small amounts of DMS in wine can give the wine a pleasant "jammy" character. High amounts still lead to vegetal off-flavors in wine. This may or may not have a similar effect for sour beers with fruit <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1238928866135325/?comment_id=1239199406108271&reply_comment_id=1240351815993030&comment_tracking=%7B%22tn%22%3A%22R%22%7D Conversation with John Frederick on MTF. 02/25/2016.]</ref>.