Gravity problems

[mrveeno]

I will try to make this as short as possible. The problem started when I dropped my primary fermenter on 9 Oct. It had been in the primary for 8 days. I let it settle back down for another week, yeast was still active. I put it in the secondaries on 16 Oct and just read the Gravity today at 1.030. It tastes fairly sweet, but it is a winter ale. Any suggestions? Should I just let it set, maybe pitch a touch more yeast?

Thanks, Veeno

 

[thehaze]

Well, if the beer isn't done fermenting, then why moving it away from the yeast cake, to a secondary? If it is not done fermenting, you need to let it ferment further, possibly increase temp. a bit.

What was the OG, the grain bill, the yeast and how much did you use for how many gallons/liters?

1.030 is pretty high, but if the beer started at 1.100 then it could be OK with some conditioning.

 

[myndflyte]

Yup, need to know what the OG was. Also, dropping your fermentor, while not suggested, isn't going to stall your fermentation, if that was what you were worried about.

 

[kh54s10]

I agree with the previous. Dropping the fermenter would do nothing to stall the fermentation. More than likely it would have helped by getting the yeast stirred back into solution. 1.030 might be where you want to be depending on the recipe.

If fermentation was not finished you should have left it in primary until it did finish. I know that some will transfer a little before hitting FG but IMO that is not best. But then again I rarely do a secondary.

 

[LarMoeCur]

To trouble shoot correctly, we need the recipe, SG, yeast pitch info, and some of your processes. There's only about 1,000 things that can affect attenuation.

 

[mrveeno]

SG or OG was 1.061. I have pretty much always left my brews for one week in the primary, then two in the secondaries. Never a problem. My fermentation is always strong the day after brewing, and I have to use a blowoff tube. I use 2 packs dry yeast with a starter for a 10 gallon batch.
FG should be 1.012.

22 lb 2-row
3 lbs Munich Malt
1 lb Crystal Malt - 80L
1 lb Crystal Malt -120L
1 lb Carafa

 

[LarMoeCur]

How many liters was your starter? Did you use a stir plate with the starter or just oxygen? How many gallons of wort went into the fermenter?

90% of beer that under attenuates by .018 points is way under pitched or the starting yeasts was compromised in some way. Off the top of my head you needed a 5-6 liter starter or 30 grams of properly rehydrated dry yeast.

If you do repitch make sure the yeast is actively fermenting. Make a starter and at or just before high krausen pitch otherwise it will just sink to the bottom.

 

[mrveeno]

About 12 gallons in the primary.

I always make a starter, 1000ml and it is very active, or I don't use it. No stir plate, I manually swish it in the container. I oxygenate with 100% before pitching. As I said, once fermenting starts it is very active, never had an underpitch problem with any other beer I have made for 6 years now. Seems like a gallon and a half of starter would water down the beer.

 

[LarMoeCur]

There are two things that stand out to me. The first is 12 gallons of 1.061 needs at least a 5 liter starter. So you pitch about 1/5 the required liquid yeast. I know you used dry yeast. Still 17.25g short of ideal dry yeast pitch.

The second is you pitched 11.5 grams of yeast into a 1 liter starter. There is not enough sugar in a 1 liter starter to force a growth phase from that amount of yeast.

Yeast can be trained. If you talk to professional brewers, they think the best beer comes from the fourth or fifth batches of beer on the same yeast. Because they have trained the yeast to do what they want. You way over pitched your starter hoping to get it the yeast active. What you trained them to do is shorten the growth phase because there is not enough sugar to feed all of them. Then you way underpitch your beer. The yeast repeat the shortened growth phase and the realize there's way more sugar then they can handle alone! By then it's to late they have already started producing CO2 and alcohol. Now the environment is still rich in sugars but toxic. So the yeast army depleted before they could finish the mission.

When I make a big starter, I start the starter 3-4 days before my brew day. I put it on my stirplate for about 12-18 hours. Then I let it sit until my brew day. On brew day I move it to my fermentation chamber and start get it acclimated to the temperature. By the time I'm ready to pitch all of the yeast is in a nice cake at the bottom. I decant almost all of the spent starter wort off the top. Leaving just the yeast cake and enough beer to mix it up into a slurry.

Oxygen is key for a growth phase in Yeast. I would oxygenate your starter. Not sure that swishing it around is enough. I guess you could shake the hell out of it. But 10 seconds of pure O2 or a stirplate would surely grow more yeast.

 

[mrveeno]

There are two things that stand out to me. The first is 12 gallons of 1.061 needs at least a 5 liter starter. So you pitch about 1/5 the required liquid yeast. I know you used dry yeast. Still 17.25g short of ideal dry yeast pitch.

The second is you pitched 11.5 grams of yeast into a 1 liter starter. There is not enough sugar in a 1 liter starter to force a growth phase from that amount of yeast.

Yeast can be trained. If you talk to professional brewers, they think the best beer comes from the fourth or fifth batches of beer on the same yeast. Because they have trained the yeast to do what they want. You way over pitched your starter hoping to get it the yeast active. What you trained them to do is shorten the growth phase because there is not enough sugar to feed all of them. Then you way underpitch your beer. The yeast repeat the shortened growth phase and the realize there's way more sugar then they can handle alone! By then it's to late they have already started producing CO2 and alcohol. Now the environment is still rich in sugars but toxic. So the yeast army depleted before they could finish the mission.

When I make a big starter, I start the starter 3-4 days before my brew day. I put it on my stirplate for about 12-18 hours. Then I let it sit until my brew day. On brew day I move it to my fermentation chamber and start get it acclimated to the temperature. By the time I'm ready to pitch all of the yeast is in a nice cake at the bottom. I decant almost all of the spent starter wort off the top. Leaving just the yeast cake and enough beer to mix it up into a slurry.

Oxygen is key for a growth phase in Yeast. I would oxygenate your starter. Not sure that swishing it around is enough. I guess you could shake the hell out of it. But 10 seconds of pure O2 or a stirplate would surely grow more yeast.

Funny this is the first time this has happened to one of my batches. So what do you use for a starter, I use a light DME. Again, 5 liters seems like a lot of flavorless fluid to put into a batch of beer.
On the other hand, I could start it 10 minutes before I use it, just to make sure it is good yeast.

 

[Smellyglove]

If you use a refractometer for reading SG values post-fermentation then try with a hydrometer. 1.030ish is typical refractometer-reading when someone asks this question.

 

[LarMoeCur]

Not all yeast act the same even the same strain from the same brand. Your initial yeast package could have a very low viability rate. Because it was damage some how you may have only pitched 5g of healthy yeast. Hard to say what exactly went wrong. If a beer under attenuates 95% change it was under pitched or the yeast had health issues.

I'm using light DME for my starters and I'm NOT pitching 5 liters of yeast into my beer. I'm making a starter consisting of 5 liters of 1.040 wort. I then decanting almost all of the spent beer and just pitch the yeast cake. I'm only putting about a cup of yeast slurry in my beer and it has zero affect on the taste.

 

[mrveeno]

If you use a refractometer for reading SG values post-fermentation then try with a hydrometer. 1.030ish is typical refractometer-reading when someone asks this question.

I use a hydrometer, thanks.

 

[mrveeno]

Not all yeast act the same even the same strain from the same brand. Your initial yeast package could have a very low viability rate. Because it was damage some how you may have only pitched 5g of healthy yeast. Hard to say what exactly went wrong. If a beer under attenuates 95% change it was under pitched or the yeast had health issues.

I'm using light DME for my starters and I'm NOT pitching 5 liters of yeast into my beer. I'm making a starter consisting of 5 liters of 1.040 wort. I then decanting almost all of the spent beer and just pitch the yeast cake. I'm only putting about a cup of yeast slurry in my beer and it has zero affect on the taste.

You're talking way above my head. You save wort to do this? You probably reuse yeast as well, I've never done that. I'll look it up on youtube. It's down to 1.020 today, and there's a little bubble/foaming. I'll let it go another week, since I'll be away anywho.

Thanks for everyone's input,
Veeno

 

[Morrey]

If you use a refractometer for reading SG values post-fermentation then try with a hydrometer. 1.030ish is typical refractometer-reading when someone asks this question.

The OP is using a floating hydrometer as stated, but you are so right that 1.030ish is around the SG reading you'll get when reading a 1.012-1.015 FG with a refractometer with alcohol present.

 

[LarMoeCur]

You're talking way above my head. You save wort to do this? You probably reuse yeast as well, I've never done that. I'll look it up on youtube. It's down to 1.020 today, and there's a little bubble/foaming. I'll let it go another week, since I'll be away anywho.
Veeno

No, I use light DME. Wort is general term used in brewing. It refers to any ground malt or other grain mixed with water before fermentation. So, DME mixed with water is wort.

I'm making wort for my starter by mixing DME with water. The gravity of a starter should be around 1.035-1.045. I always shoot for a 1.040 gravity for starters. If you let a starter ferment out completely you do not need to use in the beer sitting on top of the yeast. The yeast will flocculate to the bottom of the starter. You can decant the spent beer right off the top with out disturbing the yeast cake on the bottom.