Stuck fermentation, worth re-starting?

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mrbippers

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I used the following grain bill for a sweet stout (5 gal). Grains were steeped at 155 F for 30 min then extract/lactose added followed by 60 minute boil.

6# Golden light LME
1# Lactose
1# Black Patent
12oz Crystal 75

OG came in at 1.050. For yeast I was using Safale US-04 rehydrated in a pint of water ahead of time. When bringing the bowl of yeast out my wife spilled a decent portion of it. I pitched what was left and moved the fermenter in. When I checked it 2 days later the ambient temp had crept up to 79 F and all signs of fermentation had stopped with a FG of 1.022. I moved it to the basement @ 69 F and a few days later added a yeast starter of about a half pack of Nottingham in. That was three days ago. No signs of fermentation right now and I'm at a 1.017 FG.

My question is should I try to repitch another starter with a gradual ramp up or should I just deal with it being a little/sweet light and move on? Thanks.
 

bdupree

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with that much lactose, thats about as low as it's going to get
 
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mrbippers

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Thank you. Beersmith had the estimated FG down around a 1.011 but I somewhat doubted that.
 

dcp27

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beersmith assumes everything is as fermentable as each other. lactose is unfermentable so you'll be higher than the estimate. likewise, if you use sugar, you'll likely be lower.
 

jsweet

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Also, I have found that, for extract brews at least, Beersmith tends to overestimate the attenuation just in general. At least IME, that is, YMMV. (I mostly use US-05, for reference)

For me, if a beer 1) has a stable SG <= 1.020, 2) doesn't taste overly sweet for the style, and 3) is reasonably clear and tasty, then it's ready to bottle.
 

metal850

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Seems a little high for a 1.050 OG beer, probably should wait a little while and see if it drops a some more, it seems like it's not that stable yet as it has dropped from 1.022 to 1.017.

I'm assuming you are using Safale S-04, not US-05, I couldn't find Safale US-04. But I think the attenuation is rated around 75%, so I would expect it to finish around 1.013-1.014.
 

dcp27

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just noticed something, how did you only get an OG of 1.05? the DME alone should have put you over that.

I'm assuming you are using Safale S-04, not US-05, I couldn't find Safale US-04. But I think the attenuation is rated around 75%, so I would expect it to finish around 1.013-1.014.
lactose is unfermentable so you would need to add its gravity contributions to the FG.
 

jsweet

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just noticed something, how did you only get an OG of 1.05? the DME alone should have put you over that.
Just a guess, perhaps the OP is topping off and not measuring it, and is making a (false) assumption about where the 5-gal line is on the carboy? My first few batches came out with low OGs (about as much lower as the OP is reporting here) and then I finally measured out 5 gallons of water into my carboy, and I was like, "Oh."

Now I have a measuring stick I made for my brew kettle so I can tell what volume I have post-boil, and then I actually measure the top-off water. Since then, my OGs have been dead-on.
 

metal850

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lactose is unfermentable so you would need to add its gravity contributions to the FG.
oh right, should be about .005 high according to promash... so 1.017 doesnt seem too far off.

Just a guess, perhaps the OP is topping off and not measuring it, and is making a (false) assumption about where the 5-gal line is on the carboy? My first few batches came out with low OGs (about as much lower as the OP is reporting here) and then I finally measured out 5 gallons of water into my carboy, and I was like, "Oh."

Now I have a measuring stick I made for my brew kettle so I can tell what volume I have post-boil, and then I actually measure the top-off water. Since then, my OGs have been dead-on.
According to my calc OP would have to be off by 1.1 gallons, that seems like a lot to me.

Maybe the OG measurment is off? idk
 

jsweet

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According to my calc OP would have to be off by 1.1 gallons, that seems like a lot to me.

Maybe the OG measurment is off? idk
If you are brewing 5 gallons in a 6.5-gal carboy (like my first two batches) and just try to "eyeball" it, it is easy to be off by a full gallon.

It's also possible the top-off water just wasn't mixed well enough. Revvy, for example, swears it's impossible to mix the top-off water well enough to get an accurate reading. I am confident my readings are accurate, but then again, I put a stopper in the carboy, pick the whole damn thing up, and shake the hell out of it.
 
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