Editing Sulfate

Sulfate (SO₄^2–) is an ion naturally present in [[water]], and including any brewing salts added, it is the main source of sulfate in [[wort]]. In beer, sulfate ions add dryness, accentuate the bitterness of hops, and lend a crisp finish to the beer. The dryness/sweetness balance of the beer is likely affected by not just the concentration of sulfate, but also the ratio of the sulfate to [[chloride]] ions.<ref name=smart1/> Brewing literature suggests a wide range of maximum levels for sulfate in the brewing water, up to 500 ppm (mg/L).<ref name=water/><ref name=bsp/><ref name=esslinger>Krottenthaler M, Glas K. Brew water. In: Esslinger HM, ed. [[Library|''Handbook of Brewing: Processes, Technology, Markets.'']] Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA; 2009.</ref> This is likely because the desirable level of sulfate depends on the style of beer,<ref name=monmay/> the relative level of [[chloride]] ions present, and personal preference. Sulfate is absorbed to a limited extent by yeast cells during [[fermentation]], and can facilitate [[sulfite]] formation.<ref name=monmay/><ref name=eumbam>Eumann M. [https://www.sciencedirect.com/science/article/abs/pii/B9781845690038500095 Chapter 9: Water in brewing.] In: Bamforth CW, ed. [[Library|''Brewing: New Technologies.'']] Woodhead Publishing; 2006:183–207.</ref>

'''Beer sulfate content:''' The level of sulfate in commercial beer is typically around 150 to 200 mg/L, although it can range to over 400 mg/L based on variability in the water and the brewer's preference.<ref name=kunze>Kunze W. Hendel O, ed. [[Library|''Technology Brewing & Malting.'']] 6th ed. VLB Berlin; 2019:711.</ref><ref>Buiatti S. [https://www.sciencedirect.com/science/article/abs/pii/B9780123738912000201 Chapter 20: Beer Composition: An Overview.] In: Preedy VR, ed. [[Library|''Beer in Health and Disease Prevention.'']] Academic Press; 2009:213–225.</ref>

* '''Brewing water''' - Sulfate levels in tap water can range up to 600 mg/L, although most fresh water contains less than 100 mg/L.<ref>Platikanov S, Hernández A, González S, Cortina JL, Tauler R, Devesa R. [https://www.sciencedirect.com/science/article/abs/pii/S0039914016307275 Predicting consumer preferences for mineral composition of bottled and tap water.] ''Talanta.'' 2017;162:1–9.</ref><ref name=burdie>Burlingame GA, Dietrich AM, Whelton AJ. [https://awwa.onlinelibrary.wiley.com/doi/abs/10.1002/j.1551-8833.2007.tb07930.x Understanding the basics of tap water taste.] ''J Am Water Works Assoc.'' 2007;99(5):100–111.</ref>

* '''Salt additives''' - Brewers often add sulfate salts to modify the flavor balance of the beer, depending on the style of beer and personal preference. [[Calcium sulfate]] and [[magnesium sulfate]] are commonly used for this purpose. If [[sulfite]] is used during [[mashing]] (i.e. [[low oxygen brewing]]), it will oxidize, adding a small amount of sulfate to the beer.

* '''Flavor''' - In relatively moderate amounts (200-400 ppm), sulfate ion has a dry and bitter effect on the palate.<ref name=hob>Taylor DG. Water. In: Stewart GG, Russell I, Anstruther A, eds. [[Library|''Handbook of Brewing.'']] 3rd ed. CRC Press; 2017.</ref><ref name=comrie>Comrie AA. [https://onlinelibrary.wiley.com/doi/pdf/10.1002/j.2050-0416.1967.tb03050.x Brewing liquor—a review.] ''J Inst Brew.'' 1967;73(4):335–346.</ref><ref name=water>Palmer J, Kaminski C. [[Library|''Water: A Comprehensive Guide for Brewers.'']] Brewers Publications; 2013.</ref><ref name=eumann>Eumann M, Schildbach S. [https://onlinelibrary.wiley.com/doi/10.1002/jib.18 125^th Anniversary review: Water sources and treatment in brewing.] ''J Inst Brew.'' 2012;118:12–21.</ref><ref name=bsp/><ref name=eumbam/> This effect can be used to accentuates hop bitterness, making the bitterness seem drier and more crisp.<ref name=water/> At higher levels, the resulting bitterness can become harsh, astringent, and unpleasant.<ref name=water/> [[Chloride]] ion can be used to help balance the dryness of sulfate.<ref name=bsp>Briggs DE, Boulton CA, Brookes PA, Stevens R. [[Library|''Brewing Science and Practice.'']] Woodhead Publishing Limited and CRC Press LLC; 2004.</ref><ref name=smart1>Howe S. Raw materials. In: Smart C, ed. [[Library|''The Craft Brewing Handbook.'']] Woodhead Publishing; 2019.</ref><ref name=monmay/> Many Czech and German lager brewers avoid sulfates entirely, because they find that it ruins the soft noble hop character of Pils and Helles style beers.<ref name=water/> High sulfate levels may also be undesirable in dark beers.<ref name=fix>Fix G. [[Library|''Principles of Brewing Science.'']] 2nd ed. Brewers Publications; 1999.</ref> Lastly, sulfate is more likely to impart an unpleasant harshness when combined with higher levels of [[sodium]]. Therefore, the more sulfate there is in the water, the less sodium there should be (and vice versa).<ref name=monmay/>