whitmorr86
Member
Can anyone shed some light on the differences between adding prior to boil vs mid-boil or flameout? I understand it can change color but I'm wondering if there are any effects on body or flavor.
Adding extract
- Thread starter whitmorr86
- Start date
Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:
starrfish
Well-Known Member
No flavor or body difference... unless you have a Really BAD scorching problem with 1 hour boil. I've gone to last 15 min on my partial mashes. working out great!
mojotele
Well-Known Member
It can also affect how many IBUs you get out of your hops. A lower gravity boil, even for a bit, means the hops will contribute more IBUs.
NorCalAngler
Well-Known Member
You want your boil gravity to match the gravity of the expected boil in the recipe. For example, if you are working from a 5 gallon boil recipe and you are only boiling 2.5 gallons then you want to add 1/2 the extract at the beginning in order to keep the boil gravity the same. You then add the other half near the end or at flameout (once you turn the heat source off). This ensures your hop utilization is the same as expected in the recipe.
SumnerH
Well-Known Member
That's not exactly true.
From the Journal of the American Society of Brewing Chemists:
"In the range 10.5-13.5° P, no relationship between hop utilization and original gravity was found."
From March 20, 2008 - What Is an IBU . . . Really? at http://www.basicbrewing.com/index.php?page=basic-brewing-radio-2008
Now, the amount of break material that precipitates out can actually affect the IBUs you get; if all other factors are equal, an all-malted-barley 1.030 wort will have less break material than an all-malted-barley 1.050 wort, so will maintain more IBUs. But that's not a function of boil gravity, and just shifting the addition to the end won't make there be any less break material.
Really it's a pretty complicated situation, though as Palmer notes in that interview there are still good reasons--mainly color and avoiding any unwanted caramelization--to do late extract additions. But the exact extent of the impact on final IBUs is pretty muddy:
The whole interview is worth listening to, really; it doesn't reach any cut-and-dry guidelines for home brewers, but gives you a lot of stuff to consider when thinking about hop utilization in different kinds of beers.
mojotele
Well-Known Member
Wow, that's a lot of info! I'll have to give that interview a listen and stop repeating that old mantra, then. Thanks!
NorCalAngler
Well-Known Member
So the entire discussion is pointless for most brewers then. If these very technical discussions don't result in applications then what is the point? I think Jamil Z and John Palmer's recommendation to keep boil gravity the same as recipe gravity is still the most sound advice I've read/heard regarding extract addition.
NorCalAngler
Well-Known Member
So the entire discussion is pointless for most casual brewers then. If these very technical discussions don't result in applications then what is the point? I think Jamil Z and John Palmer's recommendation to keep boil gravity the same as recipe gravity is still the most sound advice I've read/heard regarding extract addition.
SumnerH
Well-Known Member
They do reach actionable conclusions, just no bright-line rules. A few of the takeaways I got were:
1. When calculating IBUs, a beer with lots of simple sugar (cane/dextrose/candi syrup/etc) is going to have higher utilization than most formulas predict.
2. Wheat, rye, and other grains with a lot of break material are going to cause lower than expected utilization.
3. Hops with a more balanced alpha:beta ratio are going to lose bittering capability more slowly than alpha-centric hops. A high-alpha hop like Galena which has a ~1.5 alpha:beta ratio is going to lose less bittering capability sitting in your freezer for a few months than one like Chinook that has a alpha:beta ratio in the realm of 3.5 (that doesn't mean the flavor won't shift some as the proportion of oxidized betas rises, but the overall bittering ability will be lost less quickly).
There's plenty more--it's a fascinating and informative show.
None of these are "plug number X into the equation" kinds of cut-and-dried rules, but that doesn't mean that they don't help you with recipe formulation when home brewing.
I mean, most people totally guess at adjustments when faced with aging hops; having a little more info to inform those guesses is useful.
Yeah, it seems to make sense.
It doesn't make sense that just keeping the boil gravity the same as the final gravity will keep the hop utilization the same.
If you're doing a 2.5 gallon boil for a 5 gallon batch you're putting in the full amount of hops in half as much water. Won't you reach a point where the acid from the hops won't dissolve as readily due to the high concentration of hop acid in the wort? Maybe this is only an issue for the most bitter beers or maybe it isn't an issue at all.
If you're doing a 2.5 gallon boil for a 5 gallon batch you're putting in the full amount of hops in half as much water. Won't you reach a point where the acid from the hops won't dissolve as readily due to the high concentration of hop acid in the wort? Maybe this is only an issue for the most bitter beers or maybe it isn't an issue at all.
SumnerH
Well-Known Member
Yes. At some point you're going to reach saturation--if you're doing a 2.5 gallon boil and diluting it with relatively pure water, the theoretical limit is going to be 1/2 of what you could get into a 5-gallon boil.
Whether that theoretical limit is close enough to anything we ever approach in practice is a question I don't know the answer to. It didn't seem to matter with the beers I made when I did partial boils, but I never went over about 70 IBUs or so.
NorCalAngler
Well-Known Member
I'll have to re-read the section in Brewing Classic Styles that discusses this, but from memory I believe they state the volume of liquid in a partial boil is more than enough to utilize hops to their fullest.
I just used the 'Search inside this book' feature at Amazon and found the following:
[I]Brewing Classic Styles[/I] pages 30 & 31. said:
Good to know.
SumnerH
Well-Known Member
Good to know, though the bolded part is exactly what John Palmer and others are now saying isn't true--in the interview I linked upthread, Palmer even says that his most recent version of How to Brew got this wrong (as well as many other common home brewing texts).
