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DMS is a very volatile compound. Scheuren et al. (2016) determined that there is not a significant difference in DMS evaporation in water versus wort, and came up with equations for determining the evaporation of DMS in water using the laws of thermodynamics. They presented a somewhat counter intuitive result that DMS actually volatilizes more readily as temperatures drop, until about 50°C (volatilization of DMS drops significantly under 50°C). Their calculations state that 3.2% of the total wort volume needs to be evaporated for 90% of the DMS to volatilize at 100°C, whereas only 1.3% of the total wort volume needs to be evaporated for 90% of the DMS to volatilize at 80°C (keep in mind that the rate of evaporation at 80°C is much slower, and thus it takes more time to reach 1.3% evaporation). This indicates that some amount of DMS is evaporating off at temperatures below boiling until 50°C is reached <ref name="Scheuren2016mbaa"></ref><ref name="Scheuren2016"></ref>.
They also established that the volatility of DMS is the same regardless of the concentration gravity of the wort (although the presence of sucrose does greatly increase the volatility of DMS), and that it is instead effected by temperature, atmospheric pressure, and the concentration of DMS (higher concentration of DMS slightly raises the volatility of DMS ) <ref name="Scheuren2016mbaa"></ref>). A larger top surface area will allow for faster evaporation of the total DMS present in the wort, but the total DMS present in the wort would eventually be evaporated off regardless of what the top surface area of the kettle is <ref name="Scheuren2016"></ref>. In order to limit DMS in the end product, it is advised to allow no more than 100 µg/L of DMS into the fermenter <ref name="Scheuren2016mbaa">Influence of Extract on Volatility of Flavor Components in Wort During Open and Closed Boil. Hans Scheuren Roland Feilner, Frank-Jürgen Methner, and Michael Dillenburger. MBAA website. 2016.</ref>.
Much of the DMS in wort from the SMM precursor is volatilized off during fermentation due to off-gassing of CO2. However, if high amounts of DMS survive the boil then off-gassing from fermentation may not be enough to volatilize all of the DMS. Shape and type of the fermenter also play a role in how much DMS is volatilized during fermentation, for example Anderson et al. and Booer & Wilson showed that open fermentation leads to less DMS production compared to closed fermentation <ref name="Anness"></ref>. Higher fermentation temperatures (18°C versus 9-12°C, for example) can lead to higher rates of DMS volatilization <ref name="narziss2008">[http://www.wiley.com/WileyCDA/WileyTitle/productCd-3527659889.html Die Bierbrauerei: Band 2: Die Technologie der Würzebereitung, 8 Auflage. Ludwig Narziss. 2008. Section 5.6.4.3.]</ref>. DMS can spike towards the end of fermentation from yeast metabolizing DMSO into DMS (see [[Dimethyl_Sulfide#DMSO_Precursor|DMSO Precursor]]) <ref name="Anness"></ref>.