Increasing ABV of half the batch

[JayUnt]

I brew 10 gallon batches split up between 2 buckets. I am going to make an IPA but wanted to make them a bit different. I was thinking of adding something to one of the buckets and leaving the other the same.

When I was designing the recipe I was going back and forth about the ABV. So my latest idea is to make each batch different ABV. I was thinking about adding extra sugar to one of the batches to boost it. I was reading that you can do that but it's better to wait until initial fermentation is already underway, to let the sugar eat the complex sugars first.

I know its going to dry out the and was wondering if there was anything to do to make it not too dry. Does adding extract after initial fermentation work the same as sugar would, but prevent the dryness? Or since that is more complex, should I add it before fermentation starts? I know it wouldn't boost the ABV as much, but I could just add more.

I still have to figure out how much sugar I would want to add, because it might not be enough to dry out the batch too much and then I wouldn't have to deal with the extract. But I'm still working it out.

Thanks!

 

[Bellybuster]

personally, I would drain the first 5 gallons into fermenter then add some DME to the other half still in the kettle.

 

[JayUnt]

After its cooled? So you would go with extract over just sugar. Thanks.

 

[NTexBrewer]

It is pretty simple to use math to help you make the decision.

Cane Suger is 46ppg
DME is 44ppg

Batch A is your first batch
Batch B is your batch you want to increase the ABV

Lets assume for a 5 gallon batch you have an OG of 1.060 and you get 80% attenuation.

60 points X .8 = 48
60 - 48 = 12

Your final gravity of would be 1.012

(1.060 - 1.012) X 131 = 6.2% ABV

If you add 1 pound of cane sugar you will add 46/5 = 9.2 points to your OG but since cane sugar is completely fermentable you FG will remain the same.

(1.069 - 1.012) X 131 = 7.5% ABV

If you add 1 pound of DME you add 44/5 = 8.8 points to your OG but this time you will get 80% attenuation.

68.8 X .8 = 55.04
68.8 - 55.04 = 13.76

Your final gravity would be 1.014

(1.0688 - 1.014) x 131 = 7.2%

So with this example
Batch A would be 6.2% FG 1.012
Batch B with 1lb Cane Sugar would be 7.5% FG 1.012
Batch B with 1lb DME would be 7.2% FG 1.014

 

[JayUnt]

Oh wow. That is awesome information. Now I'm kind of thinking about shooting for the same abv in both versions, but using cane sugar in one and malt extract in the other. That would show me the differences between the FGs. If I could fit 3 fermentors in my chest freezer, I would try all 3 versions. Thanks again.

 

[DurtyChemist]

What about using 3 gallon better bottles and splitting the batch that way? Different sugar sources including honey or molasses.

 

[JayUnt]

Unfortunately I don't have 3 gallon BBs, so I won't be doing that. If I did, I would go with the regular, cane (or corn) sugar and DME. Would be a fun test to see all of the differences.