10 gallons to 10 Barrels Hopping Help

To add... if you read the pro forums, they don't really seem to be keeping trade secrets regarding this issue. They are sharing their experiences pretty openly. It's just that no two breweries ever seem to have the same experience in terms of how to scale up from Tinseth-sized batches (or whatever). This is the main reason I added a user adjustable hop utlization multiplier parameter in BrewCipher...there was a commercial brewery using it and they asked for the IBU calcs to be adjusted to reflect their experience. The fact that breweries seem to be finding very different scale-up factors strongly implies (to me anyway) that process (and not just size) is a pretty significant factor.

 

Yes, well we all know it's not just the size of the boat. It's also the motion in the ocean. Thanks.

 

I should have added that those were quotes for bittering hop additions (so 60 - 90 minutes) only. Again they are in ranges because of the factors such as boil intensity, bittering addition time, amounts, aa%, wort strength, and pH. Now I understand that you guys are looking to establish / find a general ballpark data based curve for all of those factors.

We recently had a quiz question in brew school where the teacher assumed 33% utilization for a 14% aa hop @ 90 minutes and a 5% utilization for two different 5 minute hop additions (hops in the 5-7% alpha acid range). I'll take this opportunity to pick his brain and ask how he came up with those utilization projections. If he gives an answer that seems credible / useful, I'll ask him to expand on his utilization curve methodology and then I'll share it here....

 

At my brewery (Blue Pants from Madison, Al) when I scale up a 5 gallon recipe to 1 barrel, I scale the flavor/aroma additions directly and then I do 95% of a direct scale of my bittering addition. When I step up to 15 barrels from 1 barrel, I do the same with the flavor and aroma, but I do 90% of a direct scale for the bittering addition. This has yielded very good results for my system, but obviously, other systems won't be exactly the same. I do think that it is a good rule of thumb though if you are brewing with a gas burner at home though and the brewery is doing direct fire. Water chemistry will play a big role in scaling your recipe as will wort pH. Good luck!

 

Oh! I should have added that I move back all of my flavor/aroma additions to being 10 minutes later in the boil as well. With the increased headspace of the larger system, I found that the flavor and aroma seemed to be driven off more during whirlpool if I didn't push back the additions.

 

Any chance your aroma additions seem reduced because of the extra time it takes to transfer to the chiller rather than being due to the increased head space in one of your vessels? I'd think they would be flashing off more due to the extended time they sit in the whirlpool at a very high temperature. That also seems (to me) to be a more likely cause considering you claim that adding them later in the boil seems to alleviate the phenomenon. After all, how would adding the hops later in the boil have any bearing on an effect you believe is due to head space (a constant)? Just an observation. Please correct me if I'm overlooking something here. I often do and am eager to learn.

 

That should have been surface area... Not headspace. It actually only takes me 15 minutes to run the worth through our heat exchanger, so I don't think that is the cause. It takes me about the same amount of time to chill 1 barrel as it does 15 barrels. The one barrel is very tall and skinny, where the 15 barrel is what you would expect for a brewhouse of its size. It is possible that the 15 bbl system has a higher heat retention through the whirlpool and that could effect the isomerization, potentially leading to more bitterness and less flavor. We whirlpool for 10 minutes and let it settle for 25 minutes, so it is a pretty significant amount of time. The surface area being so great though, it allows for more steam to escape and carry off the hoppy aroma.

 

Thanks for the clarification and elaboration. 15 bbl through the heat exchanger in 15 minutes? Wow it takes a lot longer to run 10 bbl through the heat exchanger at the brewery I'm apprenticing at. Then again we are chilling with municipal water and using a 1 stage heat exchanger so we have to reduce our flow rate to get the wort output to reach pitching temperature. Are you using a CLT or a 2 stage heat exchanger by chance? Must be nice getting the brew day done faster!

 

We normally have a CLT (spare fermenter or brite tank) and we have second stage glycol for fine tuning the output temp. We do occasionally use city water, but we have two supplies. We hook both of them to the chiller using a T and then use second stage glycol. It takes us about 20 minutes to do it that way. We double batch and quadruple batch though, so if our chilling time took as long as it used to, we would be in for some really crappy days.

 

From what I have gathered, the two main factors in this increased utilization are 1) reduced surface area to volume, leading to less resins sticking to the surfaces and more in the beer and 2) longer times in contact with hot wort, ie whirlpools, rests, transfer time, etc. Moving hop additions to later in the boil or to the whirlpool makes sense to me as far as a scaling strategy goes.

 

Would you then agree that we can thus far summarize scaling up as having at least the following 4 effects on late additions?

Of course they are system/process specific to some extent.......

1. An increase in ibu's due to the larger mass of wort's increased heat retention
2. An increase in ibu's due to longer hop contact times w/ said hot wort via potentially longer transfer times to the chiller
3. A decrease in volatile hop aromas due to additional heat flash caused by both #1 and #2
4. A decrease in both ibu's and volatile hop aromas due to more vessel surface area for hop resins to get caught on

And that, while moving those additions to later in the process does nothing with regards to the wort's increased heat retention (1) or surface area (4), doing so will lower the contact time those additions have with hot wort which mitigates (2) and (3) to some degree?

 

I believe 2 and 4 are correct. Regarding 1, boiling is boiling in my mind, the larger mass does not increase IBUs. Regarding 4, I could probably argue that homebrews result in more flash due to boiling in an uncovered vessel. Prof breweries I believe have only a vent, most of the kettle is covered.

I also believe the lower SA to volume in a production kettle will increase hop flavor and aroma as Vikeman described. Less liquid surface area for the volatiles to escape, more volume for the oils to stay in solution. This is mostly all theoretical guesses.

 

My thought on #1 was that the larger mass of wort retains more heat after flame out during the time that the beer remains in the kettle and whirlpool prior to passing through the heat exchanger. As for #4, it's my understanding that volatile aroma compounds will flash off to some degree until the wort is below roughly 110F. But yes I understand where you are coming from. Some oils may evaporate, condensate on the lid (again system specific), and fall back into the wort. Some may do the same in the vent if they don't get caught in the drip catcher designed to prevent condensed DMS from falling back into the wort. Definitely theoretical, but when lacking real data that's all we can do

 

Come to think of it, that is an assumption on my part. Perhaps those quotes are considered to be an overall average of all standard hop additions during the course of a brew? Not really sure and I'm now suggesting that because.....

I got a message from my brewing school instructor (former brew master of Otter Creek / Wolavers and current owner / head brewer of Drop In Brewing) stating he uses the following hop utilization estimates.

"I use the following with pellets for average wort gravities I brew at 12-16 P
60-90min 38%
45min 30%
30min 25%
10min 20%
5min 15%
whirlpool 12%"

P.S. FWIW He also mentioned that he refuses to use Promash and Beersmith because he feels the way they calculate utilization is a major weak point of the software.

 

awesome.