WHIRLPOOL HOPPING – 80°C VS 100°C

Triangle tasting the beers hopped at different temperatures

This is a question that has been brought up through the ‘ask JK’ emails a few times and after looking online there‘s a lot of debate about the most effective temperature for whirlpool hopping. The theory behind whirlpool hopping at 80°C is that delicate hop essences are less likely to be driven off and there will be a higher proportion in the wort, meaning greater hop aroma and flavour. I’ve personally never done it this way preferring to utilize the alpha acids contained within the hops to provide a smoother bitterness while at the same time providing aroma and flavour to the beer. I’ve always stuck with this as it means that I get a pleasant bitterness, use less bittering hops and suffer less wort losses.

I decided we needed a definitive answer to this so I decided to split batch a New Zealand Pilsner and whirlpool hop it at 100°C and at 80°C;

RECIPE:

OG: 1.050

95.2% Pilsner Malt

4.8% Acidulated Malt

HOPS:

10g Herkules @ 60 minutes

160g Motueka

Theoretical Ibu: 43.7

Hop Addition

I split this batch down after boiling into two 10 litre batches and began chilling one down to 80°C. I whirlpool hopped the batch that was still at 100°C with 80g of Motueka for 30 mins and when the second half of the batch reached 80°C I whirlpool hopped that with 80g of Motueka for 30 mins.

PRODUCTION SCHEDULE:

This was fermented for 14 days at 12°C, bottled and then lagered for four weeks at 1°C

RESULTS

To determine what effect whirlpool hopping at two different temperatures has on the overall hop character of the beer I conducted a blind triangle tasting focusing on:

  • Flavour
  • Aroma
  • Overall Preference
Each participant blind tasted 3 beers - a combination of 80*C & 100*C whirlpool hopped. They were asked to identify which of the 3 was the 'different sample', which had the strongest hop flavour, strongest hop aroma and overall preference.

Each participant blind tasted 3 beers – a combination of 80°C & 100°C whirlpool hopped. They were asked to identify which of the 3 was the ‘different sample’, which had the strongest hop flavour, strongest hop aroma and overall preference.

With regards to impact: 100% of the tasters correctly identified the ‘different’ sample with regards to flavour, aroma and bitterness.

FLAVOUR: 100% of the tasters choose the 100°C whirlpooling sample stating it had superior hop flavour.

AROMA: 100% of the tasters choose the 100°C whirlpooling sample to be aromatically superior.

PREFERENCE: Overall preference was split but comments collected showed that those who preferred the 80°C sample liked the mellow bitterness and weren’t fans of high IBU beers i.e. they preferred it as it had less bitterness – wierdo’s! 😉

I tested the bitterness of both samples by running them through the Spectrophotometer at work; results as follows:

 

Spectrophotometer used for measuring bitterness

Spectrophotometer used for measuring bitterness

 

IBU 100°C whirlpooling: 45.5

IBU 80°C Whirlpooling: 30.8

An interesting experiment with fairly conclusive results – does this confirm or go against your whirlpooling hops experiences?

Formerly of Fullers, Thornbridge and Buxton. Now a freelance Black IPA advocate, homebrew geezer and creator of Baby Back Bacon Black IPA™

10 Comments

  • Reply February 18, 2015

    Jim

    How do you do your whirlpool hopping JK?

    Just a simple hop stand? +/- stirring? A pump to recirculate the wort?

    • Reply February 23, 2015

      JK

      Hi Jim,

      I throw my hops in, give them a good stir then leave them for 10 mins…they tend to float so after 10 mins I give them another stir and whirlpool. once the whirlpool is complete I put my immersion chiller in and then leave it alone till the time is up (30mins total).

      Oh, I only use pellets by the way.

      Cheers

      JK

  • Reply February 21, 2015

    Pete

    I have preferred my ~80℃ hopstand beers, but I do like to avoid the “earwax” taste in hops.

    • Reply February 23, 2015

      JK

      Hi Pete,

      Earwax? Can’t say I’ve ever encountered that!

      Cheers

      JK

  • Reply March 1, 2015

    Dan

    Great article once again!

    When you calculated the initial IBU what utilisation figure did you use for the hopstand? Just wondering since the 100C batch came out pretty close.

    Thanks, Dan

    • Reply February 5, 2016

      A King

      Plugging those amounts of hops into brewers friend, I get that he got ~5% utilization, which sounds reasonable, if a bit on the low end of estimates I’ve seen on various forums.

  • Reply July 1, 2015

    andrea93

    hi!
    during hopstand do you keep a lid on the kettle to maintain the temperature and avoid something fall in the kettle?

    • Reply July 3, 2015

      James Kemp

      Hi Andrea,

      There’s no need to maintain the temperature during the whirlpool because you are going to chill your wort down to pitching temperature straight after anyway. The temperature will remain above 80C the whole time so you will still get the isomerization of hop acids so no need to worry about the temperature drop. As for putting the lid on, you don’t want to condense any volatiles and re-solubilise them in your wort so best to leave the lid off or at most, just partially cover the kettle. Hope this helps.

  • Reply December 9, 2016

    Nick

    Hey mate, can we conclude from this experiment that you then got 0 IBU contribution from the 80 degree C hop addition? I’m planning a lowish IBU beer (20 – 22) and was thinking about both a flameout 100c addition and a hop stand addition at 72c. Beer smith estimates 22.5 IBU based on 18g Galaxy at 5min and 16g Galaxy at flameout with a 30min whirlpool. i’m wondering whether I’ll add IBU if I do a 35g addition once the wort reaches 72 degrees.

    • Reply January 5, 2017

      Samuel Williams

      Hi Nick, based on the recipe given the 10g of Magnum at 60 minutes should have given a theoretical IBU of ~18 so the 80 degree hop addition does contribute some way towards the total IBU but the utilisation works out at something like 2.7%. Hops will isomerise until about 79c so I think with your whirlpool at 72c you won’t be adding bitterness to your beer!

Leave a Reply