Mr. No-Tip
Well-Known Member
- Joined
- 26/9/11
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Let me preface this by saying that I realise the ridiculousness of this thread title. Why would you let PBW pass hops? I wanted to do a test run of my brown pump and hop rocket without risking a brew, so grabbed some low value (but not old and still very green) hops and test pumped it at cleanup time.
The PBW had soaked in my kettle overnight and was reheated to 90 degrees - it's not crystal clear, but far from brown:
What came out of the pump/hop rocket/kettle combo was a while other story:
It wasn't as dark as it appears in this photo, but very much like a dark IPA colour. I eliminated both the pump and chiller as the source of the colour - my chiller was cleaned yesterday and the dark colour was clear in the hose upstream from the chiller. The pump was new and never used, but no amount of loose oil or whatever in the new brown pump could do this. I also tried the PBW direct on some new hops in a jar to compare - same thing - not quite as dark as the pumped version but still darker than I'd expect.
Then I tried it with hot water of a similar temperature:
Much greener, less brown, as expected.
And the spent hops side by side - notice the reddish tinge to the PBW hops:
Obviously this has no practical relevance in brewing, but the whole thing did intrigue me. Why is this happening? Something to do with the alkaline in PBW?
The PBW had soaked in my kettle overnight and was reheated to 90 degrees - it's not crystal clear, but far from brown:
What came out of the pump/hop rocket/kettle combo was a while other story:
It wasn't as dark as it appears in this photo, but very much like a dark IPA colour. I eliminated both the pump and chiller as the source of the colour - my chiller was cleaned yesterday and the dark colour was clear in the hose upstream from the chiller. The pump was new and never used, but no amount of loose oil or whatever in the new brown pump could do this. I also tried the PBW direct on some new hops in a jar to compare - same thing - not quite as dark as the pumped version but still darker than I'd expect.
Then I tried it with hot water of a similar temperature:
Much greener, less brown, as expected.
And the spent hops side by side - notice the reddish tinge to the PBW hops:
Obviously this has no practical relevance in brewing, but the whole thing did intrigue me. Why is this happening? Something to do with the alkaline in PBW?