Hops Wort Absorption

According to BYO malt absorbs roughly 1.04L of water per kg malt. Knowing this makes calculating things like mash and sparge water quite a bit easier.

Is there a rough absorption rate for hops?

I've searched round the web but cannot seem to find anything. I guess it may vary according to the hop size and density, but some rough figures will help with calculations like topping up water and rackable post-fermentation volume.

Is there a difference between adding hops in the boil vs dry hop?

• Good question. I suspect it must be something. If I put 2oz of hops into my hop spider, when I dump it out it must may weigh more than 2oz right? I suppose a way to test it would be to put 1oz in and when you pull your spider or hop back out weigh it? Commented Oct 26, 2018 at 17:45

2 Answers

I use an Italian made brew calculator, Calcoliamo Birra, app that calculates hops water absorption at 0.12 qt/oz which is about half a cup per ounce.

Update: Last night I made a hop tea to increase the bitterness in a pilsner I wasn't satisfied with. I decided to collect some data for hops liquid absorption while I was at it. I boiled one ounce of Saaz pellets in a quart of water for 15 min, then pours the contents through a strainer lined with cheese cloth to filter the hops particles. I then let it sit until no more liquid was dripping. I then transferred the hops to a graduated measuring cup. The final volume was right at 1 cup maybe a little under. The 1 ounce of Saaz took up about a quarter of a cup, preboil. The hops absorbed approximately 3/4 of a cup of liquid in the 15 min boil.

Beer-N-BBQ by Larry says hops absorb 0,0033L of wort per gram. I don't know where the value actually comes from though.

• Beer-N-BBQ by Larry just cut a video this year where he placed hops absorption rate at 0.353 qt/oz. However that experiment was at 150°F (mashing temp so that no evaporation was taking place to interfere with hops absorption calculations) and he allowed the mash to go for an hour. I would be interested to see how duration affects hops absorption as well. Do the hops absorb more liquor the longer they steep? Possibly it will, possibly not. But if you have nothing else to go by, 0.353 qt/oz is what he measured. Source video Commented Oct 19, 2021 at 16:40