Wanted full strength, got mid strength beer

[R0berto]

Hi all, Im new at this forum and to brewing in general, so here goes....
I have a problem with my Cerveza that I have brewed from a kit. I fermented it in a 20 litre barrel for 5 days, and then finished it off in a 20 litre cornelius keg with a third of a cup of dextrose as a primer for 25 days, then chilled it and then tapped it. Starting Grav was 1.040, at kegging, I had a reading of 1.020 and then just before chilling, it was still at 1.020. My maths are saying that this equates to a beer of 2.62% ABV, falling short of an expected 4.8% - 5.0% Although I charged the keg at priming with Co2, the beer is still on the flat side as well. The beer is ok to taste, but clearly lacks that "kick" that a full strength beer gives.
It is summer here and we have had a few warm days, but the hottest my brew got was 30 degrees Celsius for half a day at brewing stage. Other than that, it has held between 26 and 22 the remainder of the time.

I would like some advice on what could be going wrong in the process here.

cheers, and thanks in advance.

 

[PatrickGoss]

Hi all, Im new at this forum and to brewing in general, so here goes....

I have a problem with my Cerveza that I have brewed from a kit. I fermented it in a 20 litre barrel for 5 days, and then finished it off in a 20 litre cornelius keg with a third of a cup of dextrose as a primer for 25 days, then chilled it and then tapped it. Starting Grav was 1.040, at kegging, I had a reading of 1.020 and then just before chilling, it was still at 1.020. My maths are saying that this equates to a beer of 2.62% ABV, falling short of an expected 4.8% - 5.0% Although I charged the keg at priming with Co2, the beer is still on the flat side as well. The beer is ok to taste, but clearly lacks that "kick" that a full strength beer gives.

It is summer here and we have had a few warm days, but the hottest my brew got was 30 degrees Celsius for half a day at brewing stage. Other than that, it has held between 26 and 22 the remainder of the time.



I would like some advice on what could be going wrong in the process here.



cheers, and thanks in advance.

Sounds like you pulled the beer out of primary too soon. Side note to that, no need to "finish" the beer in a keg. Leave it in primary until the gravity is where it should be (or damn close). Then put it in a keg and carb it up. Sometimes beer is done in 5 days, sometimes it is five weeks. Give the yeast time and they will reward you with better beer.

 

[LiquidChemistry]

Sounds like you pulled the beer out of primary too soon. Side note to that, no need to "finish" the beer in a keg. Leave it in primary until the gravity is where it should be (or damn close). Then put it in a keg and carb it up. Sometimes beer is done in 5 days, sometimes it is five weeks. Give the yeast time and they will reward you with better beer.

+1 on this. Pitch your yeast and don't transfer anywhere for at least 2 weeks. Unless I'm doing a complex beer like souring or oak/fruit aging, I don't bother with secondaries at all.

 

[Gnomebrewer]

Hmm, this sounds a bit odd. As LC said, you'd generally leave your beer in primary until completed (most brewers leave it for two to three weeks), although there is some evidence that transferring to keg earlier (before fermentation is finished) will reduce oxidation. That's a process for later though, when you're a more advanced brewer. For now, ferment for at least two weeks before transferring to keg.

How are you measuring gravity: hydrometer, or refractometer?
A refractometer gives a skewed reading for final gravity - it needs adjusting.

Does the beer taste sweet?
If the final gravity is 1.020, there are still residual sugars. Warm the keg up, pitch some new yeast and leave it for a couple of weeks. You'll need to vent the pressure several times (assuming you do this in the keg) and will end up with more sediment, but will have better beer.

 

[JonM]

Use more extract. Shoot for starting gravity around 1.050 or 1.060.

Oh, and extract sometimes tends to finish at 1.020 and not go any lower. People call it the 1.020 curse.

 

[Hwk-I-St8]

Sounds like you pulled the beer out of primary too soon. Side note to that, no need to "finish" the beer in a keg. Leave it in primary until the gravity is where it should be (or damn close). Then put it in a keg and carb it up. Sometimes beer is done in 5 days, sometimes it is five weeks. Give the yeast time and they will reward you with better beer.

Help out someone who hasn't brewed since the 90's. I've been back through my brewing book, but I haven't seen the answer to this. You say "Leave it in the primary until the gravity is where it should be....".

How do you know where it "should be"?

 

[laredo7mm]

...How do you know where it "should be"?

When the gravity stops dropping and you get the same number on two or three day intervals.

For example: you think it is done, measure the gravity, wait two or three days, measure the gravity. If it is the same number it is probably done. If it is still decreasing wait two or three more days and measure again. Repeat until there is no difference between measurements taken 2 or 3 days apart.

 

[R0berto]

On the can kit it says I should expect a 4.7 to 5.0 percent beer.

 

[RM-MN]

When the gravity stops dropping and you get the same number on two or three day intervals.

For example: you think it is done, measure the gravity, wait two or three days, measure the gravity. If it is the same number it is probably done. If it is still decreasing wait two or three more days and measure again. Repeat until there is no difference between measurements taken 2 or 3 days apart.

This is part of the answer but not quite complete. I had a beer fermentation stall. It stayed at the same gravity for more than a week but when I went to bottle it I noticed it was way higher than it should have been. I had moved it to a table to do the siphoning to the bottling bucket and when I noticed how high the gravity was I put it back on the floor where the fermentation restarted and it finished out in another week. Had I bottled that I would have ended up with bottle bombs.

When you brew your batch of beer, note the OG (measured or what the kit says if using an extract kit). Then look at the yeast you are planning to use. It will have a range of expected attenuation. (often 70 to 75% but can vary) Now calculate (or let software do that) what the projected attenuation would give for a final gravity. If your beer isn't close to that it probably isn't done.

Often the kits will have an expected OG and FG. That makes a good place to start.

 

[Hwk-I-St8]

This is part of the answer but not quite complete. I had a beer fermentation stall. It stayed at the same gravity for more than a week but when I went to bottle it I noticed it was way higher than it should have been. I had moved it to a table to do the siphoning to the bottling bucket and when I noticed how high the gravity was I put it back on the floor where the fermentation restarted and it finished out in another week. Had I bottled that I would have ended up with bottle bombs.

When you brew your batch of beer, note the OG (measured or what the kit says if using an extract kit). Then look at the yeast you are planning to use. It will have a range of expected attenuation. (often 70 to 75% but can vary) Now calculate (or let software do that) what the projected attenuation would give for a final gravity. If your beer isn't close to that it probably isn't done.

Often the kits will have an expected OG and FG. That makes a good place to start.

So the attenuation is the percent of the sugars that should be consumed by the yeast? So with an attenuation of 75% and a OG of 1.065 you'd expect a FG of 1.065 - (.75 * 0.065) = 1.016?

 

[RM-MN]

That's how I figure it. If the FG came in at 1.018 or 1.014, I'd say that was just the variation that the yeast sometimes give but if I measured a final gravity of 1.032, I'd know something was wrong. That would either be me taking a reading with a refractometer without correcting for the alcohol or a stalled fermentation. Some yeasts attenuate more than others too. One I know about is Danstar Belle Saison which attenuates much more than most. Danstar Windsor will attenuate less.

 

[Gnomebrewer]

So the attenuation is the percent of the sugars that should be consumed by the yeast? So with an attenuation of 75% and a OG of 1.065 you'd expect a FG of 1.065 - (.75 * 0.065) = 1.016?

Maybe. It depends on the fermentability of the wort as well as the yeast attenuation. Fermentatability of wort depends on ingredients and mash temp.