Dry Hop Bible

After sampling some pungent IPAs last weekend, I came to the realization that my own hop-forward beers could benefit from a better understanding of commercial hopping regimens. Specifically, I was most interested in finding the average pounds of hops per barrel of beer (lb/bbl) used in commercial dry hopping.

My first stop (as usual) was HomeBrewTalk.com, where I found mostly anecdotal information. Then I jumped over to the AHA forums, where I found similar anecdotal info. From there I surfed the pages of Probrewer.com (hoping for actual commercial insight), but to no avail. One interesting finding is that many homebrewers are dry hopping their IPAs at rates as high as 1-1.5 oz/gall (2-3 lb/bbl)!

Still in search of commercial insight, I jumped from the web to my library of brewing books, where I pulled out two recent publications; IPA: Brewing Techniques, Recipes and the Evolution of India Pale Ale and For The Love of Hops: The Practical Guide to Aroma, Bitterness and the Culture of Hops. Flipping through the pertinent chapters on dry hopping, I was able to compile some obvious and not-so-obvious insight. Coupled with Peter Wolfe’s OSU Masters Thesis and Van Havig’s Rock Bottom Experiment, I was able to create the following dry hop “cheat sheet”:

General Dry Hop Information:

  • Dry Hopping with whole conesBitterness canbe extracted via dry hopping via humulinones (Wolfe)
  • Pellets are widely used as dry hopping medium in US (Wolfe, IPA)
  • Lack of common approach to dry hopping execution among different breweries (Wolfe)
  • Hops used for dry hopping retain most of their starting alpha acid content (Wolfe)
  • Most brewers felt dry hop aroma declines rapidly within three weeks of bottling (Wolfe)
  • Dry hopping could have a positive effect on shelf life (Wolfe)
  • Packaging mediums have different effect on “scalping” the aromatics (Wolfe)
  • Most breweries dry hop after primary fermentation to prevent yeast from absorbing hop flavors and allowing yeast harvest (IPA)
  • Pellets do not give the same “fresh hop” aroma as whole cones, but are close (IPA)
  • Longer post boil residence (whirlpool) resulted in more hop flavor, aroma, and perceived bitterness than shorter (contradicts traditional methods of quick chill) (Van Havig)
  • Longer post boil residence resulted in more hop flavor than dry hopping alone, therefore hop flavor is best developed in the kettle (Van Havig)
  • No relationship found between measured bitterness and hop flavor/aroma, but significant correlations were found between perceived bitterness and hop flavor/aroma (Van Havig)
  • Combination of late hopping and dry hopping resulted in greater aroma than dry hopping alone (Van Havig)

Dry Hop Temperature:

  • Warmer dry hopping improves dry hop extraction (For The Love Of Hops)
    • Stone at 62F
    • Lagunitas at 70F (w/yeast)
    • New Belgium at 54F (w/yeast)
    • Sierra Nevada at 68F (w/yeast)

Dry Hop Duration/Frequency:

  • Limit dry hopping to 5-15 days (IPA)
  • Most commercial dry hopping regimens last anywhere between 3 days to 1 week, even up to 1 month (Wolfe)
  • Pellets show more rapid and higher overall extraction than whole hops (Wolfe)
  • Whole cones benefit from longer contact time (Wolfe)
  • Stirred pellet hops are nearly full-extracted after 24 hours (Wolfe)
  • Unstirred pellet hops showed very little change between 6 hours and 4 days (Wolfe)
  • Unstirred pellets achieved between 56-73% of the overall aroma intensity as stirred, peaking at 4 days (Wolfe)
  • Hop aroma compound extraction may peak as soon as 300 minutes at 23C, less than 3 days at 1-4C (benchtop) (Wolfe)
  • Bitterness intensity and duration increased with extaction time and between the dry hopping regimens (Wolfe)
  • Stirred or “roused” dry hops resulted in greater overall aroma intensity, bitterness, and astringency relative to unstirred methods (Wolfe, For The Love Of Hops)
  • Multistage dry hopping adds greater depth of flavor (IPA)
  • Examples (For The Love Of Hops)
    • Firestone Walker Union Jack IPA – two doses of dry hops (no more than 3 days per dose)
    • Russian River – two doses over 6-14 days for most beers with 8-10 for Blind Pig, and 12-14 for Pliny The Elder

Dry Hop Rate:

  • Brewers can reach a point of diminishing return with dry hopping (Van Havig)
  • Dry hopping rate reported between 0.25-1.5 oz/gal (0.5-3 lb/bbl) (Wolfe)
  • Examples (For The Love Of Hops)
    • Stone 0.34-0.65 oz/gal (0.66-1.25 lb/bbl) but typically 0.26-0.52 oz/gal (0.5-1.0 lb/bbl)
    • Lagunitas 0.26-0.77 oz/gal (0.5-1.5 lb/bbl)
    • New Belgium 0.46oz/gal (0.9 lb/bbl)
  • Examples (read below)
    • Double IPAs 0.78 oz/gal (1.51 lb/bbl) for 11 days (mostly single dose)
    • IPAs 0.48 oz/gal (0.93 lb/bbl) for 9 days (mostly single dose)
    • Black IPAs 0.40 oz/gal (0.78 lb/bbl) for 12 days (mostly single dose)

While this data is extremely useful, it only gave three commercial examples of dry hopping lb/bbl. Averaged together, Stone, Lagunitas, and New Beligum use 0.5 oz/gal (0.95 lb/bbl) of dry hops.

Yearning for most commercial examples, I utilized several books and websites to find verified commercial brewing recipes (not clones, but actual recipes!). I want to continue to grow this list, so if you have found a verified recipe, please add a comment below and I will get it added right away!

Below is the chart. It can also be access here (http://dryhop.thirdleapbrew.com).

This information will certainly help point me in a better direction for achieving hop aroma in my IPAs, and I hope it will for you too!

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