First big batch has high FG

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chris102984

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For my first big batch of beer i decided to brew a big beer. By big batch i mean 5 gallons (I upgraded from a Mr Beer after making a few non-kit master pieces that everyone loved). My OG was 1.090 and now after 30+ days in the primary I've been stuck at 1.035. I didnt do a starter, but I did pitch two vials of yeast. On the plus side, it tastes amazing (everyone that has tasted it agrees). I'm worried that if I bottle I will have some bombs just waiting to go off causing a mess of beer and glass. I tried a half of a beano to see if that'd lower the gravity at all, it dropped zero points.

I started brewing later at night not realizing i was out of Irish moss so i do have some stuff floating, fortunately it is a dark beer. Could i have so much particulate from the steeping grains that my gravity is high?
 
Your gravity is related to dissolved sugar, nothing else, afaik. I think that with the high gravity (hard to get oxygen dissolved with that much sugar in solution), and the lack of a large starter, your yeast just couldn't finish the job. Take SG readings a few days apart, if it is not dropping, it should be good to bottle. While 1.035 is sweet, there is plenty of alcohol in there, since you started so high, to balance it. Probably why it tastes good, which is all that matters. Carbonation will also bring the sweetness down. You don't talk about your hops, but if those were large that can also be balancing it out.

I would never use irish moss in a dark beer, seems like a waste of time and money. You could move the beer to a secondary to try and leave the chunks behind. This might restart your fermentation and drop your beer a couple of points too.
 
Your gravity is related to dissolved sugar, nothing else, afaik. I think that with the high gravity (hard to get oxygen dissolved with that much sugar in solution), and the lack of a large starter, your yeast just couldn't finish the job. Take SG readings a few days apart, if it is not dropping, it should be good to bottle. While 1.035 is sweet, there is plenty of alcohol in there, since you started so high, to balance it. Probably why it tastes good, which is all that matters. Carbonation will also bring the sweetness down. You don't talk about your hops, but if those were large that can also be balancing it out.

I would never use irish moss in a dark beer, seems like a waste of time and money. You could move the beer to a secondary to try and leave the chunks behind. This might restart your fermentation and drop your beer a couple of points too.

I forgot to mention, i actually did pitch a bit more yeast without any further fermentation occurring. Maybe the secondary is the way to go to see if it drops any more.

I have another beer going simultaneously that i used a decent sized starter on, it started at 1.065 and is stopped at 1.020, is this too high also i wonder?
 
Could also depend on the type of sugar you have in there. Your gravity may be high in part due to the amount of unfermentable sugar you have in there.
 
Your gravity is related to dissolved sugar, nothing else, afaik.

My understanding of the gravity is that it represents the density of your beer. This can be influenced by both fermentable and non-fermentable ingredients that are in the beer. If the OP used a significant amount of ingredients that weren't particularly fermentable this could be the cause of the high FG.

If the OP could post the recipe used in brewing this batch it would probably be a lot easier to figure out if their FG is completely out of whack or not.
 
My understanding of the gravity is that it represents the density of your beer. This can be influenced by both fermentable and non-fermentable ingredients that are in the beer. If the OP used a significant amount of ingredients that weren't particularly fermentable this could be the cause of the high FG.

The unfermentable bits (except for some proteins, which I'm not sure effect SG), are sugars (using the chemistry 101 definition). They are unfermentable by brewer's yeast, but they are sugars. This is why different yeast strains have different attenuation rates, some can ferment more of these longer chain sugars than others.

I have another beer going simultaneously that i used a decent sized starter on, it started at 1.065 and is stopped at 1.020, is this too high also i wonder?

Are you using extract? 1.020 is a common FG for extract based brews.
 
Well, I've been doing some reading and I probably jacked up the first brew quite a bit. It was somewhere between mashing and steeping. Anyways here goes for the first recipe:

8 lb pilsner grain (i think, didnt write down this part like i should have)
2 lb dark grain

Steeped/mashed these at 165 degrees for 45 minutes, then added that to the brew pot, topped off to 5 gallons and brought to a boil. I then added the following:

1 lb Amber DME
1 lb Light DME
3 lb Pilsen DME

I boiled for 90 minutes while continually adding hops every 10 minutes (it was my bastardization of a Dog Fish clone). This is the brew that is stuck at 1.035

Both brews used some extract. The one at 1.020 had some steeped grains (not much).

There was more to that mashing thing than I originally believed... oops. Next brew may be a more proper attempt at mashing. And I'm still amazed at how good the hacked up recipe tastes, hopefully it is able to be bottled without any bursting glass.
 
Mashing at 165 will give you a very unfermentable wort, so it makes sense that your FG is high. 152-154 is a good temp for mashing to produce a balanced wort.
 
I'd say with a beer that high, you're probably spot on for FG. You can make the appropriate calculations if you know your yeast strain's actual and apparent attenuation percentages - that would give you a better idea. Failing that, let it sit for another couple of days and measure again. If the beer is still, I would bottle.
 
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