High Gravity Brewing and Ales

Submitted by ggroff on

  1. High Gravity Brewing
    1. A technique allowing a brewer to brew a larger end-batch volume of ale without needing larger fermentation equipment. A higher specific gravity beer is first fermented, and then diluted/blended with water to produce a larger volume of a lower ABV beer, lower IBU and SRM.
    2. Advantage is producing a larger volume of beer then system allows. A 500 bbl system can produce 700 bbl of beer. For homebrewers, a 5 gal batch can produce 6-6.5 gals, maybe more if careful.
    3. Stereotypically used with American Pilsner
    4. Disadvantages
      1. Fermenting wort that is above 1.064 can add esters into final beer (fruity: banana or apple)
      2. Hop utilization decreases slightly at higher wort gravities, needing proportionally more hops needed to results in same IBU.
  2. High Gravity Ales
    1. Ales that are brewed to a higher then typical specific gravity, but are not diluted, resulting in higher ABV ale.
    2. Typically original gravities are 1.060 – 1.070 and higher.
    3. Challenges:
      1. Same as high gravity brewing; hop utilization and esters.
      2. Fermentation not starting quickly, typically requires a yeast starter.
      3. Stuck fermentation, typically from lack of oxygen as the solubility of oxygen decreases with increased wort concentration. Fermentation requires oxygen, high wort concentration leads to low O2, as fermentation goes on, the O2 is consumed and eventually gone and fermentation stops.
        1. Aerate properly
        2. Use a yeast starter
        3. Pitch more yeast
      4. Achieving complete attenuation often requires extra care
        1. longer fermentations
        2. multiple pitching
        3. rousing the yeast
          1. Agitate (old breweries used to “walk” the cask)
          2. Personal experience, racking the beer
  3. Some high gravity styles and their SG range.
    1. Barley Wines; 1.090 – 1.120
    2. India Pale Ale; 1.050 - 1.070
    3. Bock 1.066 – 1.074, Maibock 1.066 – 1.068, Doppelbock 1.074 – 1.080, Eisbock 1.092 – 1.116
    4. Fruit beers; max 1.116
    5. Old Ales; 1.057 – 1.125
    6. Strong Scotch 90/-; 1.072 – 1.085
    7. Foreign Stout; 1.052 – 1.072, Imperial Stout; 1.075 – 1.095
    8. Märzen/Oktoberfest; 1.052 – 1.064
    9. Weizen Bock; 1.065 – 1.080
  4. Recommended yeasts
    1. White Labs 
      1. WLP007 Dry English Ale
      2. WLP099 Super High Gravity Ale (ferment up to 25%)
      3. WLP500 Trappist Ale
      4. WLP510 Belgian Bastogne Ale
      5. WLP530 Abbey Ale or WLP540 Abbey IV Ale
      6. WLP570 Belgian Golden Ale
    2. Wyeast Labs
      1. 1728 Scottish Ale
      2. 1084 Irish Ale
      3. 1214 Belgian Abbey
      4. 1388 Belgian Strong
      5. 1762 Belgian Abbey II
      6. 3787 Trappist High Gravity
  5. Specific Beers
    1. Sierra Nevada Brewing Company - Bigfoot Ale
    2. New Holland Brewing Company has a High Gravity series of 8 different beers
    3. Ayinger – Celebrator Doppelbock
    4. Bell’s Brewing Company – Expedition Stout
    5. Founders Brewing Company – Harvest Ale
  6. 21% ABV All-grain Beer (http://www.byo.com/component/resource/article/51-21-alcohol-all-grain-beer)
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PDF icon High Gravity Brewing (KLOB Presentation).pdf42.68 KB