Low ABV High IBU

[Frozenpuck]

Hey guys

I made a my second batch of all grain this weekend and for the second time, I missed my OG by about 18 percent. The expected ABV was 5.5, this batch came in at 4.0.

Recipe is

9 lbs 2 row
.5 lbs crystal 60
1 lbs carafoam

.3 ounces warrior at 60
.3 ounces cascade at 30
.5 ounces cascade at 15
.5 ounces cascade flameout
1 ounce cascade dry hop

Mashed at 149 with 3.2 gallons let sit 1 hour and drained in approx 10 minutes. Sparged in two parts 2.3 gallons each. Let them sit for 2 minutes before draining.

The projected IBU is 27, projected ABV 5.5

This is a 3 part question

1. Now that my ABV is 4.0, my IBU has increased to 31, will this be an overly bitter beer for ABV of 4.0?

2. Do you see anything wrong with my sparging technique that could be driving my efficiency down?

3. Any suggestions on what I can try to improve efficiency? Based on my calcs, my efficiency is currently 56 percent!!!!!

Thanks gents

Cheers

 

[OswaldvW]

Sounds like you are batch sparging. I usually let the sparge water sit in the mash for 10-15 minutes before collecting.

 

[Iseneye]

My standard APA is 4% and around 35 IBU. It's fine to me. You haven't asked for input on the recipe but I wouldn't bother with the 30 minute addition. I usually start my additions around 10 minutes plus the bittering charge. Your other option is to get rid of both the 60 minute and 30 minute and have all the bitterness come from the later additions.

 

[Frozenpuck]

Thanks Oswald, I was actually thinking the same thing. I only let the spathe sit for 2-3 minutes, likely not long enough. I will try letting it site for 15 minutes next time before I adjust my crush setting which is currently at .042

 

[Frozenpuck]

Good thought on removing the 30 minute addition. If I get rid of the 60 and 30 minute additions, do I need to increase the late addition quantities by quite a bit? I suspect I will since the oils won't boil off as quick. Thanks.

 

[kh54s10]

The usual culprit for low OG is poor crush on the grain. The time the sparge water sits in the grain does not have very much effect. I add the water stir it, vorlauf then drain. Waiting longer, IMO, only makes the brew day longer.

Just read .042 on the mill setting. I don't have a roller mill so I am not sure but I thing most go to about .035 or even tighter.

I too think that 31 IBU is not going to be overly bitter.

You are also only talking about expected ABV. You cannot determine the actual ABV until the yeast have fermented the beer. If for instance your estimated OG was 1.050 and your estimated FG was 1.010 then you got the 1.050 abut the yeast took the FG to 1.006 your ABV would be higher than predicted.

 

[Lefou]

Want a couple tips for a drier beer and increased conversion efficiency? Several different ways or a combination of ways will do. A drier beer can yield a marginally higher ABV, so here's how.

Increase the amount of base malt, grind a small portion of your base malt (one quarter to one third) to near flour, increase your mash time. Add a measure of amylase powder to the mash/sparge water, and lower your mashing temperature slightly. Treat your mash/sparge water with calcium salts to adjust your mash pH.
I've left a couple out - like the tighter mill grind, using a gradual step mash .... but you have a lot of alternatives depending on your approach.

 

[RM-MN]

Thanks Oswald, I was actually thinking the same thing. I only let the spathe sit for 2-3 minutes, likely not long enough. I will try letting it site for 15 minutes next time before I adjust my crush setting which is currently at .042

Bring your mill gap down to .025, add a handful of rice hulls, and watch your efficiency go up. With the mill gap at .045, I think my rye grains might slip through without any crushing.

If you don't want to crush so much, adding time to the mash can help a bit with conversion. It takes time for water to get to the middle of the grain particles and gelatinize the starches. Until that happens you don't get conversion of those starches. If the mash take too long some of the enzymes needed for conversion may get destroyed by the temperature of the mash.

Sparging is only rinsing the sugars from the grains. Pour in the water, stir well, and then drain. No waiting is necessary unless you don't stir well enough.

 

[Frozenpuck]

Thanks, I'll definitely review the ABV values

 

[Frozenpuck]

Definitely some things to consider. Not sure if my brew shop has amylase powder, may need to order online. Cheers

 

[kh54s10]

Definitely some things to consider. Not sure if my brew shop has amylase powder, may need to order online. Cheers

I don't think this is a normal step. Work on your process and efficiency without adjuncts like amylase. Start with your crush.

Look at recipes, amylase is not normally a listed ingredient. Stick with just grains, hops and yeast. Maybe fruit etc.

 

[Shade]

The general answer to the 'is it too bitter' question is the BU/GU ratio - IBUs divided by your real OG less 1000. You should be able to figure out what OG you ended up with in reality, then compare to other beers that you like.

It scales up as OG increases in my experience - the higher the OG, the higher the ratio.

Eg I've made a couple of ales and shared with my father in law this weekend, he preferred the bitterness of one and the flavour profile of the other. Both had OG around 1060, bitter one had 85 IBUs, other one had 65 IBUs. I agreed on both points so I know when designing for my taste, ratio of 85 / 60 = 1.4 or so on my system is the sweet (bitter) spot.