Fermentation.....

[Milkdud76]

I brewed a Bavarian Wheat 6 days ago and the bubbles in the airlock are about 1 per minute. The recipe says to ferment for 7 days @ 70F. My temp was 68ish, should I transfer to secondary or leave for another day?

 

[Thehopguy]

leave it for another week or two

 

[JLem]

I brewed a Bavarian Wheat 6 days ago and the bubbles in the airlock are about 1 per minute. The recipe says to ferment for 7 days @ 70F. My temp was 68ish, should I transfer to secondary or leave for another day?

I would leave it for at least another week, if not two, and completely skip the secondary. Also, airlock activity is not a good indicator of fermentation progress. You really need to take a hydrometer reading to know when your beer is done.

 

[TTB-J]

Neither - you don't need to transfer to a secondary and you should probably leave it for more than just another day. Do you have a hydrometer? If so, get a reading and take another in 3 days. You'll know it's time to bottle when you're getting the exact same reading over the course of 3 days - and even then, you might consider leaving it for a couple of extra days just to make sure that it fully conditions.

 

[madchemist83]

It can condition in the bottle. Check the gravity though.

 

[unionrdr]

Or,as I do,let it sit another 3-7 days after FG is reached to allow it to settle out clear or slightly misty. Less yeast dregs in the bottle that way. As an interesting aside, am I glad I got a new roof & garage door. Bad wind storm all afternoon with rain lashing sideways.

 

[BrewingRugger]

I let my beers usually sit for 7 to 10 days in a primary then transfer to secondary for another week and then cold crash for a week. You don't have to use a secondary. I would suggest that you try it both ways and see which one you like best. Niether way is right or wrong it's what you prefer.

 

[unionrdr]

Not to mention how much cleaning you're willing to do...

 

[Milkdud76]

Thanks everyone. I'm going to get a gravity reading in the morning and go from there.
When would be a good time to keg it?

 

[Milkdud76]

Also, airlock activity is not a good indicator of fermentation progress. You really need to take a hydrometer reading to know when your beer is done.

Thanks for the info. For some reason I thought the airlock activity was important. I don't know if I read it somewhere or what.

So you're saying to take a hydrometer reading every so often and when it reaches the desired gravity, then its time to switch?

 

[madchemist83]

Airlock activity is important. For some reason people seem to think that production of CO2 is not related to fermentation. If you have air tight system airlock can show when fermentation is close to completion. But you also have to take a gravity reading.
Dissolved CO2 in green beer will lower your gravity. As beer ferments more CO2 is absorbed into green beer. Gravity also tells when all the protein falls down to the bottom. It's up to you for how long to leave ur beer in fermentor.

 

[JLem]

Airlock activity is important. For some reason people seem to think that production of CO2 is not related to fermentation. If you have air tight system airlock can show when fermentation is close to completion. But you also have to take a gravity reading.
Dissolved CO2 in green beer will lower your gravity. As beer ferments more CO2 is absorbed into green beer. Gravity also tells when all the protein falls down to the bottom. It's up to you for how long to leave ur beer in fermentor.

Yes, fermentation produces co2. And yes, airlock activity MAY be a sign of fermentation. However, it is not a reliable sign. There are reasons why you may have airlock activity and NOT have fermentation (eg increase in temperature, movement of the fermenter) and a lack of airlock activity is not an indication that you don't have fermentation or that fermentation is done. The only way to truly know if fermentation has happened/finished is by taking a gravity reading. I would rather throw my airlock out than my hydrometer/refractometer. And even if airlock activity is stopped and fermentation is complete, this is not an indication that the beer is done - there are many ancillary metabolic reactions taking place in the beer by the yeast (eg uptake of diacetyl, conversion of acetaldehyde into alcohol, etc).

Finally, the beers gravity is not affected by the proteins in suspension falling out. Gravity is essentially a measure of the liquid's density and is only affected by compounds dissolved in the solution. Things floating in the beer will not affect its density and therefore will not affect its gravity. Dissolved co2 will also not lower the gravity. If anything it may increase it.

 

[unionrdr]

In my experience,now that I've got my plastic Fv lids to seal correctly,the airlock can show when initial fermentation is finished. That's about it. The beer slowly ferments down to FG,not producing enough gas to bubble,or only sporadically. That's why I always wait till the two week mark to take a 1st FG reading. With average mid-gravity ales,that's usually pretty close to a stable FG.

 

[madchemist83]

Dissolved gases will lower gravity.

 

[JLem]

Dissolved gases will lower gravity.

I fully admit that I am no chemist, but you will have to explain this one to me. If I have 1 L of water and I dissolve some carbon dioxide in it, I now have 1 L of water plus some carbon dioxide. Since my volume didn't change (or did it?), in order for the solution to be less dense the carbonated water would need to have lost mass for its density to go down. Does adding carbon dioxide remove mass?

 

[madchemist83]

Gases have very low density compared to liquids. Volume will go up so will mass.
It's kinda like when you dissolve liquid extract in water, your combined density will be somewhere in between two densities (depending on how much you dissolve). With gases it's the same, although solubility of gases in liquid under normal conditions is way less then extract in liquid .. therefore actual impact on density will be minimal .. but it will bring density down.

 

[Milkdud76]

Took gravity reading today and it was 1.020 @ 67F. Anticipated FG is 1.013, so I'll wait a few more days and see if it lowers. Had good aroma but had an acidy taste to it.

 

[JLem]

Gases have very low density compared to liquids. Volume will go up so will mass.
It's kinda like when you dissolve liquid extract in water, your combined density will be somewhere in between two densities (depending on how much you dissolve). With gases it's the same, although solubility of gases in liquid under normal conditions is way less then extract in liquid .. therefore actual impact on density will be minimal .. but it will bring density down.

Sorry to belabor this, since I know we are essentially arguing semantics here, but any decrease in density is likely to be imperceptible given the precision of homebrew instrumentation (i.e. hydrometer). In the end, we really only need to concern ourselves with dissolved sugars and other carbohydrates when thinking about beer gravity/density.

From a chemist colleague:
"Since CO2 is non-polar and not very likely to interact significantly with water, the dissolved CO2 adds a little mass but probably does not appreciable alter the volume (other than adding the volume of the CO2 which is quite small). The complication comes in the equilibrium of CO2 and water which forms some carbonate ion. The carbonate ion is polar and
(charged) and likely interacts strongly with water thus having the potential to appreciably alter the solutions total volume.

The mole fraction of carbonate ion in the water in your case is likely very small so it will likely have a negligible effect on volume."

 

[madchemist83]

Yeah the impact is insignificant.

 

[mugen112]

Yeah the impact is insignificant.

Omg thank you for the translation madchemist I was like wtf reading the other guy lol. I forgot what I was even reading about!

 

[madchemist83]

Hehe. Chemistry is fun. Wait for us to start talking about anions.

 

[Milkdud76]

Hehe. Chemistry is fun. Wait for us to start talking about anions.

Onions in beer? That's just crazy talk.

 

[madchemist83]

No it's delicious

 

[JLem]

Onions in beer? That's just crazy talk.

You've obviously never had used a bad batch of Summit hops!

 

[JohnnyO]

You've obviously never had used a bad batch of Summit hops!

Or Oskar Blues Gubna. Yeesh.

 

[Milkdud76]

You've obviously never had used a bad batch of Summit hops!

Thats true, I've only brewed 4 batches so far.