LOW FG ! Now what??

[sleepystevenson]

Hello, All. Just kegged my Scottish 90~. Basic all grain Recipe from Jamil's Brewing Classic Styles book. Dumped on American Ale yeast cake, after removing some of the yeast from the fermenter. Single stage fermentation of 4 weeks. Mashed at 158. Fly Sparge. OG: 1.054 FG: 1.007! ( I was looking for 1.012 - 1.014 area)

The last few batches, I have been using 1.75 qt water per lb. of grain. (Always used 1.25 before) I have noticed that my efficiency has gone up significantly with this method. (Was around 70-72% now up to 79) I have also noticed that my beers have dried out a bit more in the FG department. This was a good thing for the last style (APA), however, with this scottish ale, I was hoping for more residual sweetness / body. Anybody else notice this with higher strike water ratios?

Another factor that I believe drove the attenuation was the warmer fermenting temps. Typically I like to keep it in the mid 60's, however this one was low 70's. (Due to warm weather)

So, now the question is, what can I do about the low FG on this Scottish ale?? Maybe boil some lactose in water and add it to each keg? According to beersmith, lactose potential is 1.035. (Which, I assume is per pound per gallon) So, adding 1 lb per 5 gallon keg would get me another 7 points of FG, taking me to 1.014. Am I correct here?

Not in a hurry to do anything, as the beer was just kegged yesterday. I plan on aging it for awhile (1-2 months probably) and tasting before taking any action. Anybody ever try the lactose? Or other ideas?

Thanks! And please let me know if you need more info! This is the lowest FG I have ever had. Really surprised me, though, especially with the high Sacc rest temp. (Yes, thermometers are right on!) Good learning lesson, though. From now on, I will use the higher strike water ratio for dryer beer styles!

 

[Yankeehillbrewer]

I've never brewed a Scottish before, but I think it would probably be best to just leave it alone this time.

There is a direct correlation between lower FG and Higher strike ratio. Not sure why, but there is. Fermentation temp control is key. A water bath works wonders. I use a 25 gallon rubbermaid tub, and have a bunch of old Gatorade bottles that I fill with water and freeze. Swap those out when you can and you should be able to control your temps pretty good. I'm sure pitching onto the entire cake of a previous batch has something to do with it too. That's a lot of yeast, over pitching IMO. If I'm using from the Yeast Cake, I will swirl it up real good, pour off a Quart into a Sanitized Mason Jar, dump the rest and cleanup my Primary. Then pitch the Mason Jar of slurry into the new Brew.

I know I didn't answer your question, but hopefully some of that will help get your FG's back where you want them.

 

[sleepystevenson]

Thanks for your input, YankeeHill.

Foolishly, I used the higher strike ratio, when my previous experience let me know it lent itself to lower FG's.

I did use evaporation type cooling, which did help (ambient temps were in the 80's and beer temps were low 70's) My fermenter is on a stand and too big to set in a ice water bath, so I just put a container of water under the fermenter, and wrap the fermenter in towels, with a fan blowing on them. The water wicks up the towels and cools.

As for the yeast cake, I removed one quart of the yeast slurry to save for a buddy, so there was some of it gone. I have followed this same route quite a few times before and never had this problem.

Sounds like it was the "perfect storm" of conditions that all added up to one h_ll of an attenuation!

I am definitely gonna let it age in the keg and taste it before taking any measures to alter it. Who knows, it might actually turn out good!? But, I have a feeling it is gonna be really dry.

 

[ldgenius2000]

In listening to Jamil myself, I notice when you want a malty sweeter beer in the British styles you want to use a British yeast typically because they have lower attenuation than the American ale yeasts. Might be something else to consider.

 

[phatuna]

Yes, if you want a maltier profile, you need to use the lower attenuating yeast profiles like s-04 or other English ale yeast rather than the American yeast that you used.

 

[sleepystevenson]

Agreed. However, Jamil's recipe calls for American Ale yeast for his Scottish Ale recipe.

I thought that was strange, but all his other recipes have turned out great. So, I went with it.

Oh well. A couple months conditioning will hopefully help out!

Thanks for the responses!

 

[phatuna]

Sorry not to have a suggestion for your question. I don't have any experience with trying to add something to up the FG after fermentation.

I think doing what you are doing (leaving it alone for a while) is going to be your best option.