OG higher than planned, concerned about FG. Any tips?

[scottkct]

Christmas Ale (honey, ginger, cinnamon)

Planned OG: 1.076
Measured OG: 1.088

Planned FG: 1.017
Estimated FG: 1.021 (based on WLP013 attenuation)


I overshot mash running volume. I've been having efficiency issues so I let them go over and just added to boil time to bring it to target volume. Batch sparging so not so concerned about PH. I ended up adding about 30 minutes turning my 90 minute boil to 120 minutes.

What resulted was an OG of 1.088 when I was shooting for 1.076. I'm suspecting I miscalculated some of my grain weights at LHBS. I pitched WLP013 London Ale Yeast which has 67-75% attenuation.

Basic calculations put a 75% apparent attenuation at FG of 1.021. My target FG was supposed to be 1.017.

I'm fairly new to AG, are my estimates correct and if so is there something I can do to get the FG down further? I want some residual sugars for sweetness but I'm concerned they will be too much at 1.021. I thought of pitching another yeast kind of like what you do in super high gravity but I don't want to dry it out.

Would pitching US05 help or any other type of yeast? If so at what point do I do it. I'm close to 4 days in primary right now.

Thanks!

 

[kingwood-kid]

I'd wait until the 013 is basically done, then see how you like it. Remember that it won't taste as sweet when it's carbed. If you think it's too sweet, make a starter of us-05 and pitch it when it's actively fermenting, then give it a couple of weeks.

 

[TopherM]

Did you account for the honey in your target OG measurement?

If the only thing that accounted for your higher OG was the extra 30 minute of boil time, you really should have just added some extra water after cooldown to get back to our intended OG.

As far as the FG now, I wouldn't worry too much about it. There is going to be very little difference in the flavor profile between 1.021 and 1.017. At WORST that will be a very slight residual sweetness that will probably compliment the spices and style of your beer. I wouldn't add any more yeast, just leave it in primary for 14-21 days total then bottle/keg.

Good luck!

 

[WoodlandBrew]

You can add some water. If it's in the early stages of fermentation you aren't going to notice it at all. And as a bonus you get more beer!

Assuming it's a five gallon batch add three quarts of water.

(88 x 5)/76 = 5.79

 

[helibrewer]

You could encourage the higher attenuation by fermenting on the higher end, rousing daily, and maybe 3-5g of Fermaid K. Assuming you manage temperature, the yeast will quit when they are 1) out of nutrients, 2) they reach their alcohol toxicity, or 3) they flocculate out.