Force Carbing And Increased Bitterness.

[Truman42]

Im going to assume he means that the aluminium pot loses heat better and therefore your wort cools quicker after flame out. Now that your using a stainless kettle it holds the heat better so your still extracting bitterness from the hops whilst waiting to whirlpool etc.
Interesting theory and the only way you can check if its correct is to measure your wort temperature after whirlpool in your stainless kettle and do the same in your ali kettle with all other things being equal. You could just boil some water in each and test the theory that way too. Boil for 5 minutes. Rest for 10 mins, whirpool for 30 seconds then rest for another 10 mins and check the temperature. (Or whatever process you normally use.)

In practice though I would have thought were only talking about a minor temp difference and not enough to notice a difference in bitterness.

EDIT: Did you really have to bump THIS thread....

 

[_HOME_BREW_WALLACE_]

I actually planned a side by side brew. I will let you guys know how I get on.

 

[Fat Bastard]

I'd love to hear the non-brief version..

Basically what Truman said. Assuming everything else you're doing is the same, and the boil off rates are the same, and you're hittling all your targets, the temp change is really the only thing that could be causing this. In my own brews with late hop additions, I was finding that most of my beers were turning out far more bitter than I wanted them to be. My post boil process has been to let stand for 10 minutes, whirlpool for 5, and let stand for a further 10. before running through the chiller into the FV. Initially I had been chucking the flame out additions in at the end of the boil, but have since worked out that 0 minute additions need to go in at the start of the whirlpool i.e. at minus ten from flame out and I've been playing with additions after the whirlpool as well. Bitterness is now where it should be according to the tastebuds and not just the brewing software calcs.

Post flame out process seems to be incredibly important for obtaining the correct bitterness, and until recently with the new feature on beersmith, involved a lot of guesswork and experimentation. The difference in the physical properites of your new keggle might just be enough for you to be able to taste a difference in the hop bitterness. I'd also be very interested to hear the results of your back to back tests.

Are you no-chill ? Do you run the kettle insulated or un insulated?

Hope this helps!

FB

 

[_HOME_BREW_WALLACE_]

I have done an experiment. I cubed an unhopped wort yesterday I plan to do a boil of a couple of litres and dump my hops in then. Will report when its in the keg.