Adjusting Hops When Scaling Down Recipe?

[Tyler.W]

Hi all,

I brew 2.5 gallon batches with my Anvil Foundry 6.5 and I bottle my beers (moving to kegging shortly).

I have read a few articles/sections in books that mention small batch brewing can sometimes need more hops than would normally be calculated when scaling down a recipe due to increased surface area for evaporation and kettle losses verses larger batches. I have been brewing using Brewfather and scaling all my recipes from 5 gallon batches, and although the IBU (tinseth) is supposedly correct, I notice that taste-wise it is much less. For example, I brewed a mock-marzen and although I had 24 IBU according to Brewfather, I tasted nothing. I then brewed an American Amber that had 40 IBU, and that tasted on par with other marzens in terms of bitterness that typically come around the mid-20s.

Could this be a recipe issue? Bottling issue? I also notice I get next to no hop aroma in my beers, and almost no hop character besides bitterness.

 

[McKnuckle]

I also brew 2.5 gallon batches, but have also brewed larger and smaller batches. I don't think volume has anything to do with your lack of hop character.

In my experience, hop character is far more about timing. And preservation of hop character is achieved through cold side oxygen avoidance. The latter is, of course, generally beneficial to all aspects of beer freshness.

The IBU itself is tied only to bitterness, and has no direct correlation with flavor or aroma. Those qualities are dependent on when you add the hops, and how much per dose. Flavor is preserved best with hops in the 30-10 minute range, although first wort hopping also has its place.

Aroma is good with a 5 minute addition, better with a whirlpool addition (and rest), and perhaps best - if you can preserve the freshness - with dry hopping.

Märzen is a malt-biased style. But how about that amber? What was your hop schedule for that one?

 

[BrewnWKopperKat]

Adjust hops when scaling down a recipe?

1. Initially, a linear scaling (e.g. divide by 2) gets you started (or use software).
2. Over time, you will be able to see what adjustments need to be made.
3. others with the same equipment will have experiences that can be helpful.

I have read a few articles/sections in books that mention small batch brewing can sometimes need more hops than would normally be calculated when scaling down a recipe due to increased surface area for evaporation and kettle losses verses larger batches.

I was at a local home brew club meeting (obviously a while back) where people brewed the same recipe (almost everyone was brewing "5 gallon" batches). The variation was greater than most people anticipated.

Ingredient variation is also factor - consider comparing a regionally grown hop (or a "Bell's Select" hop) the same hop from a home brew store.

I have been brewing using Brewfather and scaling all my recipes from 5 gallon batches, and although the IBU (tinseth) is supposedly correct,

Some estimates we can confirm with equipment, some estimates we can "dial in" with taste and experience.

• (link to) The IBU is a LIE! Kind of.....
• (link to) Master Brewers Association podcast 123 - Tracking IBU Through the Brewing Process: The Quest for Consistency

 

[1HW]

Also note that the smaller your batch, the harder it is to be consistent from batch to batch. Larger volumes are much less sensitive to small changes. As an analogy, about 20 years ago, salt water aquarium enthusiasts started trending towards establishing nano tanks (1 - 2 gallon aquarium cubes). Maintaining the water chem for these little guys was much more challenging than for a 125 gallon aquarium. Likewise, a small difference in one step of the brewing process on a 2.5 gal batch could make the difference between a great beer and an underwhelming one, whereas that same small difference made on a 1 bbl system may go completely unnoticed in the final result.

 

[NTexBrewer]

How are you adding hops? Hop spiders or baskets can reduce utilization. Check with Anvil as they may have some information about hop utilization for your model since it is designed to make smaller batches.

When I use my stainless steel mesh hop basket, I set my hop utilization to 75% so I’m using 1.25 times the hops to achieve the same bitterness compared to just throwing in the hops.

You may have to experiment to figure out what works for your system.

 

[Tyler.W]

Märzen is a malt-biased style. But how about that amber? What was your hop schedule for that one?

Yes, Märzen is malt-forward, but when I compare mine to a commercial offering the hop character and bitterness is non-existent even though IBU were calculated to be the same.

For my American Amber I had a calculated 38 IBU using the following schedule:

• Boil
  • 0.37oz - Nugget (13.4% AA) @ 60 min - 28.5 IBU
  • 0.10oz - Magnum (12.9% AA) @ 60 min - 7.3 IBU
• Hopstand @ 175℉ for 15 minutes
  • 0.29oz - Amarillo (7.7% AA) - Estimated 1.4 IBU
  • 0.20oz - Willamette (4.2% AA) - Estimated 0.5 IBU

How are you adding hops? Hop spiders or baskets can reduce utilization. Check with Anvil as they may have some information about hop utilization for your model since it is designed to make smaller batches.

I add the hops straight to the kettle, but I have the Anvil Kettle Strainer (below) on the output that does some filtering. In my understanding this shouldn't affect the utilization, correct?

 

[NTexBrewer]

The hop strainer should not affect utilization. I’m confused how the bitterness is being calculated with brew father. Using Brewer’s Friend your two bittering charges are producing about 50 IBU’s if my assumptions for your recipe being 3.25 per boil volume and 2.5 gallon post boil producing a 1.055 beer.

Here is a link to Brewer’s Friend IBU calculator. IBU Calculator Beer Bitterness - Brewer's Friend

Also, make sure that you are putting in the actual Alpha Acid % of the hops that you buy. This can and usually is different from what is in a recipe. Alpha Acid % change with each harvest and from growing regions.

 

[Tyler.W]

I’m confused how the bitterness is being calculated with brew father. Using Brewer’s Friend your two bittering charges are producing about 50 IBU’s if my assumptions for your recipe being 3.25 per boil volume and 2.5 gallon post boil producing a 1.055 beer.

Also, make sure that you are putting in the actual Alpha Acid % of the hops that you buy. This can and usually is different from what is in a recipe. Alpha Acid % change with each harvest and from growing regions.

I am sure to update my recipe before brewing with my actual hop AA%.

I have attached the Brew Father batch recipe for the American Amber. I have about a 1/2 gallon of wort left in the kettle after transferring about 2-3/4 gallons to my fermenter.

 

[NTexBrewer]

I am sure to update my recipe before brewing with my actual hop AA%.

I have attached the Brew Father batch recipe for the American Amber. I have about a 1/2 gallon of wort left in the kettle after transferring about 2-3/4 gallons to my fermenter.

With the total recipe with pre and post boil volumes Brewer’s Friend matches up with BrewFather with calculated IBU’s.
and if you update the actual Alpha Acid % we are back to you may just have to experiment with hopping rates on your system to dial in for your system. It would not hurt to reach out to Anvil and see what they say. This is also where being part of a homebrew club or having a good homebrew store is helpful to have them try your beer and see if they think the bittering matches what BrewFather states as the IBU’s or if you need to make adjustments.

 

[Tyler.W]

You may just have to experiment with hopping rates on your system to dial in for your system. It would not hurt to reach out to Anvil and see what they say. This is also where being part of a homebrew club or having a good homebrew store is helpful to have them try your beer and see if they think the bittering matches what BrewFather states as the IBU’s or if you need to make adjustments.

Ok, I just wanted to make sure something wasn't amiss with my process. I suppose when I think more about it I may have been generalizing my problem when there are actually different aspects to it. My bigger issue may be hop character and not necessarily IBU, because my Amber definitely is a bit more bitter than a commercial Märzen I had yesterday (at 24 IBU), but the hop character is non-existent in my beer. I suspect this may be due to me bottling. Even though I am careful, there is no denying the exposure to oxygen. At this point I am building a kegging setup, but I probably won't have that finalized until the new year.

I wish I had a LHBS. I'm just outside Nashville and our local spot closed earlier this year. I will look into local clubs to see what I can find.

 

[IslandLizard]

I wish I had a LHBS.

Where do you buy your hops? How do you store them? How old are they by the time you brew with them?

Although an LHBS can be a wonderful resource, the better ones making for a sublime mecca, sourcing from elsewhere can provide you with a larger or deeper selection.

If you mean by "hoppiness" hop flavor and aroma, they indeed are easily lost due to oxidation. But that takes a few days to a few weeks, and does fall in the time span it takes to bottle condition.
Have you sampled beer directly from the fermenter, such as drinking hydrometer samples? Are they hoppier?

 

[Tyler.W]

Where do you buy your hops? How do you store them? How old are they by the time you brew with them?

Although an LHBS can be a wonderful resource, the better ones making for a sublime mecca, sourcing from elsewhere can provide you with a larger or deeper selection.

If you mean by "hoppiness" hop flavor and aroma, they indeed are easily lost due to oxidation. But that takes a few days to a few weeks, and does fall in the time span it takes to bottle condition.
Have you sampled beer directly from the fermenter, such as drinking hydrometer samples? Are they hoppier?

I currently shop with Ritebrew. I store my hops in the freezer; double-bagged to try and keep the oxygen out. At the time of brewing the amber, the older hops were less than six months old.

It is hard to remember my perception of the hop flavor but I will take notes next time. Generally I notice that the beers taste sublime out of the fermenter, but by the time I drink them (usually 3-4 weeks of bottle conditioning) they seem to have lost some definition. I tend to find the beers taste a little off, and for a lack of a better term flabbier/blurred. Almost as if everything blends together and nothing really stands out. There is also an off-taste I pick up, but I find it hard to define. I am still developing my taste-descriptions but I think it can be a little apple/cider like, but I am not positive. I have been brewing with the same strain of Wyeast 1056 that I have harvested (overbuilt starters). I believe I am on the fourth generation, and all beers have had a similar off-flavor.

 

[IslandLizard]

I currently shop with Ritebrew. I store my hops in the freezer; double-bagged to try and keep the oxygen out. At the time of brewing the amber, the older hops were less than six months old.

As long as the hops are packaged in mylar barrier bags, vacuum sealed and/or Nitrogen flushed, and deep frozen, the hops should remain in or near their prime for a few years. So even 6 months should be no issue.

Generally I notice that the beers taste sublime out of the fermenter, but by the time I drink them (usually 3-4 weeks of bottle conditioning) they seem to have lost some definition. [...]

From what you describe, chances are the (quickly) dissipating hop sensation (flavor and aroma mostly) happens while packaged. That's likely due to oxidation. There are ways to reduce or even eliminate oxygen uptake during conditioning in the fermenter, and again during packaging, but at homebrew level, bottling pretty much always exposes the beer to air.

How long do you leave the beer in the fermenter after signs of fermentation have ceased? What kind of fermenter? I hope you don't use "secondaries." Simply eliminating those is a 95% step in the right direction already.

Have you thought about kegging? Using proper purging and transfer techniques most or all air/oxygen exposure is eliminated, keeping your beer fresher and more lively.

 

[Tyler.W]

As long as the hops are packaged in mylar barrier bags, vacuum sealed and/or Nitrogen flushed, and deep frozen, the hops should remain in or near their prime for a few years. So even 6 months should be no issue.

The hops I used were opened before for other brew days, but then I double bagged them and threw them back in the freezer.

How long do you leave the beer in the fermenter after signs of fermentation have ceased? What kind of fermenter? I hope you don't use "secondaries." Simply eliminating those is a 95% step in the right direction already.

I typically give it about 10-14 days. Fermentation slows after 3-5 typically in a temperature-controlled fridge. I was using a 3 gallon carboy, but just upgraded to the 4 gallon Anvil Bucket Fermenter (haven’t had the chance to use it yet though).

I never do secondaries, and the only time I open the fermenter is for gelatin which I am thinking about cutting out completely to avoid oxygen ingress.

Have you thought about kegging? Using proper purging and transfer techniques most or all air/oxygen exposure is eliminated, keeping your beer fresher and more lively.

Yes, I am currently building a kegging setup, but it probably won’t be ready until the new year. I CAN’T WAIT!