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Hops also contain a small percentage (~1%) of sulfur related compounds (thiols, sulfides, polysulfides, thioesters, thiopenes, and terpene derivatives). Although these levels are low, the flavor thresholds for these compounds also tends to be very low. Hydrogen sulfide can be released from these compounds during fermentation. Hops that have been treated with sulfur to prevent mildew growth (an older process that is generally no longer used) can result in increased sulfur compound such as sulfuric terpenes, and lend a garlic-like aroma in beer. Few sulfur compounds survive boiling, however late hopping and dry hopping preserves more sulfur compounds which can survive into the beer . Fermentation generally volatilizes sulfur compounds, and some are volatilizes out almost completely <ref name="Peppard_1981">[http://onlinelibrary.wiley.com/doi/10.1002/j.2050-0416.1981.tb04054.x/abstract VOLATILE ORGANOSULPHUR COMPOUNDS IN HOPS AND HOP OILS: A REVIEW. T.L. Peppard. 1981.]</ref>.

'''[https://en.wikipedia.org/wiki/Thioester Thioesters]''' are derived from an acid and a thiol. These include S-methyl hexanethioate and S-methyl heptanethioate and derivatives of these, which impart cabbagy, sulfury, and soapy flavors, and their low flavor threshold can have an impact on finished beer. Sulfides and polysulfides found in hops includes [[Dimethyl _Sulfide|dimethyl sulfide (DMS)]], dimethyl disulfide (DMSD), dimethyl trisulfide (DMST; cooked vegetable, onion). DMTS has been found in wide ranges in hops, from a few ppm to 1450 ppm, and has a very low flavor threshold (1 ppb) . These compounds are volatilized during brewing and fermentation, and are generally only found in beers that are dry hopped <ref name="Peppard_1981" />.