Stuck Fermentation? or something else?

I brewed a Milk Stout 10 days ago with an OG of 1.057 (preboil 1.045). It fermented well for only about 24 hours before dropping off. After 1 week I tested the SG and it was only at 1.030. I went to my LHBS and it was suggested that I added a yeast starter to try and get it going again. So I added that about 24 hours ago, and there is still no additional action in my airlock.

I know that the addition of 1 lb of lactose will add some unfermentable sugars, but wasn't expecting to be much above 1.020. It is sitting at a comfortable 70F. Am I missing something here? What else could be the problem? Here is the recipe I used

7# Marris Otter
1# Roasted Barley
0.5 Crystal 80
0.5 CaraPils
0.5 Chocolate Malt
0.5 Flaked Oats

Mash @ 155F, Fly Sparge with 170F

0.75 Cascade (60)
0.25 Cascade (38)

1# Lactose (38)
1 tsp Irish Moss (27)

Danstar Windsor English Ale Yeast x 2 (pitched dry on brewday, made starter with instructions, let sit 18 hours, then pitched on day 9)

Give it a full week and then check the gravity. The airlock really isn't reliable. You might also try warming it up a bit. That's gotten thing going for me before.

thanks. ill give it a week before checking again. I also got the advice from a friend to stir it up to get the yeast from the bottom back in suspension as well. I'll try that too and post back in a week.

Yeah give it a big stir. I do that for all fermentations. It kicks the yeast up and get them active again. For bigger beers it even helps degas the beer which takes stress off the yeast

You mashed high, added lactose, and used a low attenuating yeast. Might be done.

The lactose will add 7 points, so if we take that out of the equation, the remaining ingredients went from 1.050 to 1.023. About 55% attenuation. That yeast often only gets low to mid 60s. If you mashed a little higher than you thought, you may very well be done.

Calder said:

You mashed high, added lactose, and used a low attenuating yeast. Might be done.

The lactose will add 7 points, so if we take that out of the equation, the remaining ingredients went from 1.050 to 1.023. About 55% attenuation. That yeast often only gets low to mid 60s. If you mashed a little higher than you thought, you may very well be done.

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Thank you for this explanation on Lactose.

I brewed a Milk Stout extract kit a few weeks ago. It started at 1.062 and stopped at 1.030. I also used the Danstar yeast.

I spoke to the brewmaster at a local brewery and he suggested I re-pitch so I added a pack of Safale 05 a few days ago. It has gone down to 1.028 and may still drop some but it is very slow. The kit says FG is 1.020.

It has been killing me to rush home from work and check on my baby with no change in gravity.

if im not satisfied with where Im at, if it is in fact finished, would it be possible to add a higher attenuating yeast, such as nottingham, to get it down a little more? Id like to get up to 5% ABV ideally.

mcelrokj said:

if im not satisfied with where Im at, if it is in fact finished, would it be possible to add a higher attenuating yeast, such as nottingham, to get it down a little more? Id like to get up to 5% ABV ideally.

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Notty should bring it down lower.

I don't know how well just sprinkling Notty on would do. If I were to try it, I would make a small 4 pint beer with extract, about 1.050 (about 0.75 lbs LME or 0.5 lbs DME). No other additions. Shake the hell out of it and sprinkle the notty in there. Let it ferment a couple of days and add it to the main batch.

Now depending on the amount of fermentables, it might only bring it down 4 or 5 points. To get a little more out of it; after the notty has done it's work, add a pound of cane sugar (dissolved in boiling water and cooled). It will up the effective abv, and because it ferments out completely, it will lower the FG a couple of points.

5 days after pitching starter of Windsor yeast, down from 1.030 to 1.027. Thinking about maybe trying to add some nottingham, or maybe just splitting it into 2 kegs and brewing a dry stout to mix into it. most likely, ill just leave it as is and keg it soon. At this point Im up to 3.85% ABV. Ill leave it for another few days and see if I can get down another point or 2.

mcelrokj said:

most likely, ill just leave it as is.

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This.

Patience my friend. The yeast is doing its thing, so let it. Rushed beer never tastes as good.

the only thing keeping me patient is the fact that I have kegs, but no kegerator yet. so theres no rush, I know. otherwise though, I'm just too weak. I want my first kegged beer to be good, so I'll give it some more time.

Sorry to up an old thread, but i have a similar issue.

Its a milk-stout with some Christmasy spices and 1lb lactose added. I used Wyeast London Ale III (1318). Mashed at 155 on the nose, and fermenting at 65-67.

Brew day was 11 days ago, as of today its down to 1.028 from 1.054.

Would my Beersmith calculate for the Lactose not fermenting? The estimated FG was 1.011.

I'm going to check on it again in a couple days and see if there's been progress, but i don't know whether i should be looking to hit 1.011 or 1.011 plus ~7 points for the lactose.

You are probably aiming for a FG of 1.011+7. My milk stout never came down from 1.028, so I just bit the bullet and kegged it. It turned out perfectly fine, just a little less ABV than what I originally wanted. I had no problems emptying that keg FYI. I haven't used lactose since, just because I havent found a way to get the exact gravity ramifications, and I like to be in control when it comes to that.

Well, it stopped at 1.024. I made a 1L "starter" with some yeast nutrient and yeast energizer and a pack of S05. Pitched it in at high krausen, and it started bubbling away... until it stopped again at 1.024.

So i guess it's done. I moved it over to secondary. In all i added about .004 points to the gravity with the starter, so that should help make up for the lack of attenuation.

I've been reading up on mash techniques because that may be where i lost some efficiency.