What to do if yeast drop out?

[Daves1186]

So I brewed this beer http://www.brewersfriend.com/homebrew/recipe/view/94965/pecan-porter on the 5th of January and it seems that my yeast stopped working. I initially overshot my og and ended up at 1.075 instead of 1.054 but non the less I continued the process cooled and pitched the yeast. Fermentation took off within 24hrs and seemed to slow down maybe 5 days in. Long story short it's 3 weeks later and my gravity is reading 1.033. So my question is do I have to add more yeast to drop the gravity or could I just continue and rack to secondary like I was planning on today?

Thanks and btw this is my second time ever brewing anything.

 

[ColoHox]

That was quite the overshoot. What do you think was the cause?

It looks like you only got 56% attenuation, and 1056 should hit near 75%. What was your mash temp? Either your beer has too many unfermentable sugars in it or you didn't pitch enough yeast for that OG. It certainly won't hurt to pitch more yeast. That *should* solve the problem if your yeast stalled out. That grain bill should be very fermentable, although a high mash temp could leave it pretty sweet.

 

[billl]

I think you've got a measuring problem. The recipe is based on 70% efficiency, so you would have had to get almost 100% to get to where you are talking about. That is high, highly unlikely. It's probably not just a coincidence that both your OG and FG are 20 points high.

 

[Calder]

That is 12.75 lbs of grain. You can hit 1.075 with 80% efficiency (which is what I usually get).

Did you use a refractometer to measure FG? If you didn't convert right, that could be the problem.

Other possibilities could be high mash temp or cold ferm temps.

 

[Daves1186]

I fly sprayed for about an hour and I used orgainc grains which I've read could possibly extract more efficently..?? I also over boiled and ended up with about 5.6 gallons instead of 6. so that would put me around 90% efficiency if in doing the calculations correctly. I'm pretty sure my readings are correct I used a refractometer. I'm going to double check with a hydrometer after lunch. I used a 1 liter yeast starter and a wyyeast packet that I didn't rupture the nutrient pack accidentally. Thanks for the relplies.

 

[Daves1186]

So I just took a reading with my hydrometer and this what I got.

So I guess I'm right where I should be after all. My refractometer is still reading 1.034 I've never calibrated it so I think I'm going to do that before I use it again. I'm fairly confident that my og was 1.075 I remember my hydrometer and refractometer reading 1.075. During the mash I was shooting for a temperature of 154 but every 15 or so I would take a temperature reading and mix in some boiling water to bring the temp up. Half of the time it was at 149 but I got it up to around 152 for the last 20 minutes and an iodine test confirmed that I converted the sugars. I slowly fly sparged for an hour with this http://www.midwestsupplies.com/stainless-steel-sparge-arm.html with 175 degree water and then I proceeded to over boil by almost a 1/2 gallon chill and pitch the yeast. So do you guys think after me describing my process and that my og reading is accurate, if so should I change the efficency of a recipe to reflect that?

 

[frazier]

The refractometer is only accurate for the OG. Later, the alcohol throws it off. There are online calculators that will get you the right reading, such as here.

Anyway looks like "problem solved". Cheers!

 

[Daves1186]

Thanks for reminding me. I read that a while ago but with all the subtitles involved in brewing I forgot about that one.

 

[billl]

Did you make a 6 gallon batch like the recipe called for or did you bring it down to 5? The volume difference could by your issue with OG.

 

[Daves1186]

I was shooting for 6 gallons but I ended up with about 5.6 gallons.

 

[Daves1186]

It tastes pretty good, I think Im going to be happy with it. I don't think I'm up for trying this but if I were to add enough sterilized cool water to the bottling bucket to bring it up to 6 gallons would I be able to drop the beer to the intended alcohol percentage or would that screw the beer up somehow?

 

[billl]

You could dilute it, but if it tastes good, I'd just leave it.

If you have similar issues in the future, you can definitely top up to the intended volume before pitching the yeast. It will lower the gravity by whatever ratio you top up to. eg 5 to 6 would get you 5/6=83% of the measured gravity.

 

[Daves1186]

Nice thanks Bill. Yeah I'm just leaving it as is, I transferred it to secondary and I'm doing 1 gallon separately with toasted coconut. I have one more question, the next batch I make if I happen to over extract during the mash could I put the lid on my boil kettle so I don't lose any more volume while still boiling for the length of the hop additions? I'm thinking that I'll be checking the gravity with my refractometer during the boil and when it reaches the correct og I would just try to stop losing volume by putting the lid on and then just figure out what to do with the extra wort. I really don't know my efficiency and if it'll be consistent, would that work or would I just be better topping with water or some other solution. Thanks

 

[ncbrewer]

It tastes pretty good, I think Im going to be happy with it. I don't think I'm up for trying this but if I were to add enough sterilized cool water to the bottling bucket to bring it up to 6 gallons would I be able to drop the beer to the intended alcohol percentage or would that screw the beer up somehow?

I think you could be introducing oxygen with the cooled, sterilized water. I've read that it's done sometimes in commercial brewing, but I'm guessing they do something to keep oxygen out. Can anybody confirm?

 

[billl]

" the next batch I make if I happen to over extract during the mash could I put the lid on my boil kettle so I don't lose any more volume while still boiling for the length of the hop additions?"

Definitely don't do that. The boiling action vaporizes the precursor chemicals to DMS (weird veggie off flavor). If you put the lid on, the vapor will just condense and then drip back into your beer.

After a couple batches, you should be able to get your boiloff rate down to a science. The concentration of sugar works just like the dilution of sugar. So if you start with 7 gallons of 50 point wort and know you will boil down to about 5.5 in an hour, you can expect 7/5.5*50=64 point OG. (Usually a couple points less depending on how much the hops are soaking up).

So, when you start the boil, you should know pretty much where you will end the boil. If you are projecting higher than you really want you can either a) Just accept a higher OG b) dillute with a little water and finish with a higher volume of c) toss out a bit of wort and replace with water to get you to where you want to be at.

 

[Daves1186]

Awesome I'm glad I could avoid having that problem in the future. Thanks that explanation made a-lot of sense to me. I can't wait to brew my next beer whatever that may be. Does anyone out there have any tried and true low abv brews like a Berliner weis, kolsch or fruity/floral pale ale? I have a few I've been looking at but I figured I'd ask and see.