Fermentation ended

[Redleg84]

I just brewed a couple beers with similar SG, the same yeast and similar temp. The first beer had a little lag time but formed a krausen after a day and a half but it dropped out the next day.

The next beer formed a krausen quickly and it stuck around for a few days.

Now I'm assuming that the first beer didn't ferment completely. I'll check the fg when I get home to verify, but I was wondering if I had any options.

I used WLP007 yeast on the beer and I don't have any more, but I do have a vial of WLP002. Could I pitch it in there?

 

[NothingRhymesWithCurtiss]

Definitely check your gravity. Then check it again in 3 days. If it's the same, then you could consider adding yeast to finish out fermentation.

I've had quite a few beers that the krausen dropped after a day, but they carried on fermenting.

 

[Redleg84]

I checked it and it's only down to 1.035

I'm going to get the WLP002 in a starter tonight and pitch it tomorrow. I'm hoping using a different yeast isn't going to mess anything up.

Should I aerate the wort again or pitch it as-is?

 

[hou_me]

If by aerate the wort you mean shake up what's already in the fermenter, then no. That would be very bad. Check the gravity again in a day or two, it may still be fermenting. Don't start doing stuff until you know what's going on.

-ben

 

[flars]

Are you using a hydrometer or refractometer to measure SG? A refractometer will not give an accurate SG in the presence of alcohol.

What was the temperature of the fermenting wort? Fermentation can finish very rapidly if the fermenting wort was very warm. Warm fermentations can also produce off flavors.

 

[NothingRhymesWithCurtiss]

I checked it and it's only down to 1.035

I'm going to get the WLP002 in a starter tonight and pitch it tomorrow. I'm hoping using a different yeast isn't going to mess anything up.

Should I aerate the wort again or pitch it as-is?

Don't add more yeast until you've got the same gravity reading 3 days apart. But even then, I'd give it 2 weeks to let the first batch of yeast do its job.

 

[dezman]

What was the OG and how long has it been? Don't add yeast or aerate, just because fermentations acted different doesn't mean the yeast stopped working. Like others said take gravity readings every few days and make sure its going down still.

Only add new yeast as last resort. There are other things you can do first if the yeast stalls. For example warm up temp a little bit or Kick yeast back into suspension by gently stirring or swirling fermenter. Key word of last sentence is gently, you don't want to oxidize the beer at this point.

 

[Redleg84]

Are you using a hydrometer or refractometer to measure SG? A refractometer will not give an accurate SG in the presence of alcohol.

What was the temperature of the fermenting wort? Fermentation can finish very rapidly if the fermenting wort was very warm. Warm fermentations can also produce off flavors.

I was using a refractometer, I'll check it with a hydrometer real quick and see what I get.

I fermented at 64*, wort temp

 

[Redleg84]

What was the OG and how long has it been? Don't add yeast or aerate, just because fermentations acted different doesn't mean the yeast stopped working. Like others said take gravity readings every few days and make sure its going down still.

Only add new yeast as last resort. There are other things you can do first if the yeast stalls. For example warm up temp a little bit or Kick yeast back into suspension by gently stirring or swirling fermenter. Key word of last sentence is gently, you don't want to oxidize the beer at this point.

The OG was 1.055

It's been 8 days so far

I'll hold off the yeast and keep an eye on it. I fermented it at 64* and it's been held there the whole time. Should I bring the temp up to around 70* for a bit?

 

[dezman]

Yea i would give it a shot. Not familiar with refractometer use but if what other poster said is true, test with hydrometer and get accurate reading. You should be past the point now where warm temps will give off flavors so warm er up a little and see if that doesn't help.

 

[Redleg84]

Ok so I checked it with a hydrometer and it read 1.020, significantly less than I was getting with the refractometer. The target FG is 1.014 so I'm not too far off, I'm hoping raising the temp will keep it going.

I was under the impression that a refractometer would be pretty close, but it turned out to be off a good bit.

The sample wasn't bad at all, anxious to see how it finishes

 

[Singletrack]

WLP 007 is evil. I won't use it anymore. It stopped, pretended to be finished, then kicked into high gear after bottling. Bottle bombs. Tried to save the rest by bleeding pressure. Bled pressure again and again and again and many, many more times after that. If I knew then what I think I know now, I'd have dumped them all while waving a cross over the swirling drain. Evil I tell you.


But I'm sure yours will be fine.

 

[govner1]

Ok so I checked it with a hydrometer and it read 1.020, significantly less than I was getting with the refractometer. The target FG is 1.014 so I'm not too far off, I'm hoping raising the temp will keep it going.

I was under the impression that a refractometer would be pretty close, but it turned out to be off a good bit.

The sample wasn't bad at all, anxious to see how it finishes

Refractometer sate only accurate for readings before fermentation. After fermentation begins alcohol is present and affects the reading. Use a hydrometer after any fermentation has occurred.

 

[kh54s10]

Refractometers measure sugar amounts in water by measuring the bending of light. When there is alcohol present that bending changes, skewing the results. You need to use a calculator to make a mathematical correction. There are some online calculators.

Or more accurately, use a hydrometer.

 

[Redleg84]

Thanks guys, I'll leave the refractometer for brew day only

 

[Yooper]

Thanks guys, I'll leave the refractometer for brew day only

That's what I do also. However, the refractometer can still be useful after fermentation begins. For example, you can check the beer several times to see if it's done- the reading won't be accurate but if it's unchanging, you know it's done and then you can either use a hydrometer or use this calculator to guestimate the FG: http://seanterrill.com/2012/01/06/refractometer-calculator/

I love my refractometer, but it doesn't replace a hydrometer if an accurate FG is needed.

 

[ncbrewer]

I don't like a refractometer, or even a standard hydrometer, for FG. I bottle and can get a more accurate reading with a bottling hydrometer. Scale goes to 1.040, and hash marks are every .0005. It can be read very accurately, which I like for preventing bottle bombs.