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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, 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 <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>.
===Avoiding DMS===
If the brewer is experiencing unwanted DMS in no-boil/raw ale/short boiled beers:
* Avoid allowing wort to stand between 80-100°C/176-212°F (or between 80°C and your area's boiling point).
* If the wort is allowed to stand in the above mentioned temperature range, boil the wort rigorously for a few minutes afterwards, and then quickly cool it below 80°C (176°F).
* Use open and/or shallow fermenters <ref name="bamforth"></ref>.
* Increase fermentation temperature <ref name="bamforth"></ref>.
* Allow the beer to age longer, particularly if it contains ''Brettanomyces''. Studies in lambic brewing has shown that DMS will volatilize over time if left in the fermenter.
* Use more highly kilned malts such as 2 row instead of pilsner malt.
==DMS Prediction Models==
Yet another consideration is the effect of pH on the decomposition of SMM into DMS. The [[Dimethyl_Sulfide#Mashing_and_Boiling|half-life table above]] demonstrates that a difference of -0.3 pH increases the half-life by 5.5 minutes%. Unfortunately we do not have data to show if this effect is linear or not, but assuming it is linear then the conversion of SMM into DMS after the wort has soured would be greatly reduced. Assuming the effect of pH on SMM half-life is linear, and that every -0.3 pH is another 5.5+ minutes of half-life, the half-life table could be updated to include the first column:
{| class="wikitable"
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==See Also==