Dry Hopping Article

[Pope]

Interesting article about the science of dry hopping:

https://beerandbrewing.com/rethinking-bitterness-in-dry-hopped-hazy-beers/

The most surprising points for me, were that dry hopping does increase the IBU of beer and it can increase attenuation.

 

[Hoppy]

The reason for conflicting 'perceived' and 'measured' bitterness is directly related to the IBUs of the beer from kettle, before fermentation. If the bitterness is on the lower side, 20-45 IBUs, dry hopping will increase the bitterness, mainly due to the increase in humulinones (& alpha) these aren't measurable, like iso-alpha, so perceived bitterness increases. In a high IBU beer, high additions of dry hops (usually pellets) absorb amounts of iso-alpha and increases humulinones and alpha acids, which are more soluble and less bitter, resulting in a beer of lower measurable IBU. The high addition of hops also decreases pH creating an environment for iso-alpha to be precipitated.

 

[divrack]

The reason for conflicting 'perceived' and 'measured' bitterness is directly related to the IBUs of the beer from kettle, before fermentation. If the bitterness is on the lower side, 20-45 IBUs, dry hopping will increase the bitterness, mainly due to the increase in humulinones (& alpha) these aren't measurable, like iso-alpha, so perceived bitterness increases. In a high IBU beer, high additions of dry hops (usually pellets) absorb amounts of iso-alpha and increases humulinones and alpha acids, which are more soluble and less bitter, resulting in a beer of lower measurable IBU. The high addition of hops also decreases pH creating an environment for iso-alpha to be precipitated.

there's also some other stuff going on with the cohumulones it seems that might be varietal dependent.. but yes it does seem that you can get a lot

 

[James Read]

A very interesting article