Screwed up a recipe conversion?

[JSkeksi]

Tried to convert an all-grain recipe for a Chocolate Maple Porter to extract w.grain. Original recipe:

6# American 2-row
1.5# Chocolate
1# Caramel 15L
1# Black Patent

2oz Fuggle

3.75 cups Maple syrup (at end of boil)

target OG:1.066 target FG: 1.017
assumed efficiency: 75%
est. 6.5 abv


Went to the brew shop and they used their software to convert to extract and sold me:

9.9# Munton's Light LME
1# Munton's Light DME
1.5# Chocolate
1# Caramel 20L
1# Black Patent

2oz Fuggle pellets (in hop bag)

3.75 cups Maple syrup (at end of boil)

used Wyeast #1318 London Ale III

steeped the chocolate, caramel, and black patent in a grain bag for 1hour at 155F.
Added the extracts, brought to a boil, added 1.5oz hops, added .5 hops at 45 min mark.
at 60 mins killed the heat and added all the maple syrup.
cooled the wort to 70F, took the OG (1.110!!!!!!??) and pitched the yeast.

Plugged the numbers into a recipe calculator and it verifies the high OG. my reading was 1.110, the target was 1.066.

Brew calculator has the OG at 1.109, IBU's at 15, and ABV at 11.9% for what I did.

I think that I used too much extract and created a way too high gravity beer. I also worry that the yeast I pitched might not be sturdy enough to ferment this. The numbers for the gravity, ABV, and IBU are way off in the calculator.

What should I do?

 

[frozt]

I think your LHBS made a big mistake calculating your recipe. Assuming 1 cup of maple syrup weighs 11 ounces and you used US Chocolate malt:

( (9.9×36)+(1×44)+(1.5×28)+(1×35)+(1×25)+(11÷16×3.75×30))÷5 = 115.94875 = 1.115

This lines up pretty well with what you actually got for a reading.

You might get closer to your intended OG next time with something more like this:

4 lbs. Light LME
1.5 lb. US Chocolate Malt
1 lb. Caramel 20L
1 lb. Black Patent
3.75 cups Maple syrup (end of boil)

1.5 oz. Fuggles (60 min) 4.5% alpha
.5 oz. Fuggles (15 min) 4.5% alpha

Wyeast #1318 London Ale III

Estimated OG = ( (4×36)+(1.5×28)+(1×35)+(1×25)+(11÷16×3.75×30)) ÷5 = 64.66875 = 1.065
Estimated FG (75% atten.) = 1.016
ABV = 6.45

IBUS (assuming a 2.5 gal. boil)
----------
Boil Grav. = ( (4×36)+(1.5×28)+(1×35)+(1×25)) ÷2.5 = 98.4 = 1.098

Util(60) = (1.65×(.000125^.098))×((1−(e^(−.04×60) ) )÷4.15) = 0.149841339
AAU(Fuggle 60) = 1.5 oz * 4.5 alpha = 6.75 AAUs
IBU(Fuggle 60) = 6.75 AAU * 0.149841339 util * 75 / 5 gal batch = 15.171 IBUs

Util(15) = (1.65×(.000125^.098))×((1−(e^(−.04×15) ) )÷4.15) = 0.074351703
AAU(Fuggle 15) = .5 oz * 4.5 alpha = 2.25 AAUs
IBU(Fuggle 15) = 2.25 AAU * 0.074351703 util * 75 / 5 gal. batch = 2.509 IBUs

Total IBUs = 17.68 IBUs


To be honest, I can't be sure how the amount of steeped grains will affect your color and flavor (I'll leave that to someone else to answer), but I believe that the above recipe might be a good starting point for your next attempt. I'd welcome input from the others as for improvements on what I've put. As for this batch, you might try pitching more yeast if it's not too far into the fermentation. Others have reported using smaller pitches in high gravity batches without issues, so it's kindof of a toss-up.

 

[JSkeksi]

Thanks... so if I decide to pitch more yeast should I go with more of the same or should I pick a different strain more tailored to high-grav beers?

I pitched the yeast last night at about 1am so it's only been in the fermenter for 12 hours.

I'd like to salvage this batch because with the amount of ingredients incl. the maple syrup this would be a pretty expensive mistake. I know the batch isn't going to taste according to recipe but at least to get something drinkable. FWIW the wort tasted awesome.

 

[frozt]

I would probably go with more of the same strain, though some people have tried pitching different strains together for the sake of experimentation. The other option is simply to leave it alone if you're already seeing activity. The guy in this thread voted on leaving it alone.

As far as the end product is concerned, you'll probably end up with something like an imperial porter from this, which could potentially be delicious

 

[JSkeksi]

Just talked to a brewer who said I should probably pitch more yeast right away and try to get more oxygen into the wort... also that the bitterness will be off and to either try to use some coffee grounds in the wort to counteract the sweetness or try to find hop bitter extract.

 

[frozt]

I agree that the hop util will probably be off since your boil gravity was so high. I've never heard of using coffee grounds to counteract sweetness though, nor do I have any experience with hop extract. As for the extra aeration and pitching, Piratewolf's post in this thread says repitching/aeration may not help since the reproductive phase of the yeast is passed.

 

[JSkeksi]

Thanks frozt, the airlock is bubbling now so I think it's too late to re-pitch. I might consider the coffee addition for extra bitter flavor, since it would be a nice addition to the maple syrup and chocolate malts anyway. Maybe I've recreated CBS (without the barrels)? Haha well whatever it is I hope it's drinkable.

 

[frozt]

Good luck! Some of the best things in life are made completely by accident. Hope it turns out excellent.