Stuck Ferment/bad mash

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tenfingers

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Doing my first BIAB beer and the gravity has been stuck at 1.030 for the last four days or so. OG was 1.066. Yeast is Safale US-05 pitched directly into the wort and mAy have been pitched a bit on the warm side. Started bubbling after about 10-12 hours but only bubbled for one day. I've been reading around on the various possible issues and so far have tried swirling and warming (has been at 19-20 degrees the whole time) after this didn't work, I pitched new yeast (straight onto wort again not rehydrated) thinking I for sure had a stuck ferment. After two days from pitching new yeast still on 1.030 (I'm going to try raising the temp and swirling again today) and no bubbling. Checked my hydrometer to make sure it's reading 1.000 in water. Beer is an oatmeal stout with 500g of lactose in it, tastes good at the moment and a little sweet but not overly. I've read that lactose will raise the FG but from what I understand 1.030 is still too high. The brew log app I put the recipe in on my phone estimates the FG should be 1.018. I'm starting to think something may have gone wrong in the mash, I used a brand new digital thermometer and heated the strike water to 70C although I didn't stir the water and just measured the top water, maybe the mash temp was too high?. Also took a little while to cool the wort down, took it to 40C in about 10-15mins but didn't get it down to pitching temp for another few hours (had it in the sanitised fermenter). No obvious signs of infection. My question is, is it worth trying anything else or should I just let it sit for a couple more weeks, bottle it and see how it comes out?
It's my first brew so I made plenty of mistakes and I expected it would probably be less than perfect but would still like to get a decent beer if possible :)
 
I'm new to brewing, but I believe you should expect a higher FG when using lactose. As lactose is not a fermentable sugar. I've done three stouts with lactose and they all landed on 1.020-1.022 after full fermentation. And considering I only used 150g in a 10ltr batch, I would expect an FG of 1.030 if you used a whopping 500g. Correct me if I'm wrong.
 
Without knowing your exact recipe it's hard to know if 1.030 is too high.

Did you use any sort of program to figure out your recipe, if so was there an estimated FG? What was your mash schedule?

If you post up the recipe you'll get better responses.
 
Thanks for your reply, according to some posts on homebrewtalk.com 1.18pounds of lactose (535grams) should add 8 points of gravity. So I'm thinking you are probably right. I'd read a lot of different info on lactose and a lot of posts saying it doesn't add much gravity but after doing some more reading I feel better about my gravity being normalish for the amount of lactose. My FG on different software/apps is estimated at 1.015-1.018 (with the lactose plugged in to them) so I guess my gravity is just a bit high rather than of the chain.
Thanks :)
 
Recipe is:

5kg Australian Pale Malt
1kg Roasted Barley
1kg Flaked Oats
500g Lactose

40l crown urn BIAB

30-35 litres strike water


60 min mash
60 min boil

Hopped with galaxy

Finished with around 20litres of wort
 
Brewmate is telling me your OG should be 1.071 at 70% efficiency (using a potential 1.035 extract from Lactose), your OG of 1.066 gives an efficiency of about 65% which i'd say is average for your first BIAB
Brewmate says it should finish around 1.017, so I'd say you've got a while to go yet
 
Thanks for running the numbers for me Sp0rk, since my gravity has been 1.030 for 4-5 days is it safe to assume I have a stuck fermentation?
 
Give it a swirl (but don't shake).

Warm it up.

Wait a week.

Then it'll definitely be done.

As to mashing temp. Yes, stir the water.

70 degrees with that amount of grain would very likely have been perfect though to reach a 67 mash.

When you add grain, stir it well and measure the temperature again - adjust if necessary.
 
If you put 1kg of roast barley in 20L of wort then a stuck ferment is the least of your problems. Infact your wort is probably so acidic with that much RB that it is not really that surprising that your yeast conked out. I'm also not sure what other unfermentables are introduced with that much RB? In my last dark beer I put 100g of RB in a 46L batch.

Do you have a pH meter or some strips to test the wort?

Have you tasted the beer?
 
Thanks for the advice, I've tasted the beer and it's not half bad to me although I'm probably a little biased. Originally I had mostly chocolate malt and a little bit of RB but a guy at the shop talked me out of it and said better to use roasted barley instead and adjusted my recipe for me. I don't have any way to test the PH...I'll swirl it and keep it warm and see how it comes out. Lessons learned thanks for the comments.
 
After all that it has finally started bubbling away again. Third time swirling it next to the heater and it finally just kicked back to life. I looked back at my receipt for the grains and found that the mix was actually

3.5kg ale malt
1kg flaked oats
500g chocolate malt
500g roasted barley

Meaning the RB only makes up 9% of the total. I might end up with something to drink after all...thank god the guys at the shop adjusted the recipe more than I thought.
 
Wow, that's way different to what you posted earlier. So no lactose at all after all?

I'm a bit late on the scene, but in regards to you direct pitching fresh yeast when it seemed to top fermenting, you should pitch metabolically active yeast (like a starter) into beer that already has alcohol. Yeast really don't like being put straight into an alcoholic environment. Just letting you know in case it happens again in the future.
 
In that case (and assuming you still did put in the 500g of Lactose), you're looking at 1.057 OG (70% efficiency), which doesn't match up with your earlier OG...
You would have had to hit 83% efficiency, which I suppose is doable
 
Yep still has the lactose, forgot to write that. It bubbled for a few minutes and now has stopped again and the krausen is totally gone. I guess I'll keep an eye on the gravity over the next week and if it still doesn't come down ill pitch some yeast from a starter.
 
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