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Other non-thermal methods of pasteurizing barrels have been explored. Microwave treatment at 3000 W for 3 minutes of barrels filled with water reduced populations by 35% in French oak barrels and 67% in American oak barrels up to the 8 mm depth in which ''Brettanomyces'' can survive within the wood of oak barrels. High power ultrasonics (17 W/L for 3 minutes) applied to barrels filled with 60°C water kills all ''Brettanomyces'' up to 4 mm within the oak, but has limited penetration of the wood passed 4 mm <ref name="Cartwright_2018" />. The use of sulfur dioxide (SO₂) has been shown to inhibit ''Brettanomyces'' and other microbes, however, ''Brettanomyces'' cells that are exposed to sulfur dioxide can enter a state known as "viable but nonculturable" (VBNC) meaning that they cannot complete cell division (grow) but can still maintain a small amount of metabolism, and can be revived when the sulfur dioxide is no longer in their environment. Therefore, sulfur dioxide is not an effective way to completely sanitize oak barrels (although it has been used successfully to store non-infected barrels). See [[Quality_Assurance#VBNC_In_Yeast|VBNC in Yeast]] for more information.

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