Author Topic: How to check gravity while fermenting?  (Read 1137 times)

Offline glassyocean

  • 1st Kit
  • *
  • Posts: 10
    • View Profile
How to check gravity while fermenting?
« on: November 01, 2016, 09:09:03 PM »
I am a newbie to homebrewing. I started fermenting my 1st wort (5 gallon) last Saturday. It's been emitting bubbles through airlock until yesterday, and today it stopped. Read from this https://www.homebrewersassociation.org/forum/index.php?topic=5760.0 that it's no problem as long as you get to the desired FG. However, how do I check the gravities while fermenting? Opening the lid + airlock and taking a sample to measure gravity would contaminate the beer. Using spigot would also contaminate, b/c the spigot is not completely sanitized. Any thoughts? Anyways in general, is it OK to open the lid for a few seconds to check the bubbles and close it? Thx in advance!
« Last Edit: November 01, 2016, 09:19:51 PM by glassyocean »

Offline JJeffers09

  • Senior Brewmaster
  • ******
  • Posts: 1121
    • View Profile
Re: How to check gravity while fermenting?
« Reply #1 on: November 01, 2016, 09:27:40 PM »
Wait at minimum 5 days to check it.  Generally speaking with saccharomyces and average starting gravity primary fermentation (alcohol pruduction) is finished in the first 3-5 days.  So until you get a feel for the hobby, going off "rule of thumb" is my advice.  You can check it and be very careful about your sanitation.  Never touch anything your beer touches without sanitizing it.  If you have pets, put them up, they are curious and even though we love them, they are filthy.  You are looking for 1 bubble per 1.5-2 mins in the airlock.  Attenuation doesn't mean finished, 3 days with little activity (unless you have a strain that is prone to stalling or a high gravity big beer) is a good sign to start checking with a sample.

A wine thief is my preferred method of extraction.  I don't use a spigot for anything other than bottling.  I only use an auto-siphone for transfering.

Sent from my SM-S820L using Tapatalk
« Last Edit: November 01, 2016, 09:32:02 PM by JJeffers09 »
"Beer is living proof that God loves us and wants us to be happy" - Benjamin Franklin

AHA Member
Indiana Brewers Union (IBU)

Offline Stevie

  • Official Poobah of No Life.
  • *
  • Posts: 6858
    • View Profile
Re: How to check gravity while fermenting?
« Reply #2 on: November 01, 2016, 10:02:19 PM »
Whatever you do, do not poor a sample back!

Offline glassyocean

  • 1st Kit
  • *
  • Posts: 10
    • View Profile
Re: How to check gravity while fermenting?
« Reply #3 on: November 01, 2016, 11:40:19 PM »
Thank @JJeffers09 and @Stevie for the replies! Seems like things are going okay. One more Q. At the end of 2 week fermentation, is it SAFE to run beer through spigot? No concern of contamination? Thx!!

Offline JJeffers09

  • Senior Brewmaster
  • ******
  • Posts: 1121
    • View Profile
Re: How to check gravity while fermenting?
« Reply #4 on: November 01, 2016, 11:48:47 PM »
Yes. Just sanitize it with a spray bottle prior to opening

Sent from my SM-S820L using Tapatalk

"Beer is living proof that God loves us and wants us to be happy" - Benjamin Franklin

AHA Member
Indiana Brewers Union (IBU)

Offline GS

  • Assistant Brewer
  • ***
  • Posts: 167
    • View Profile
Re: How to check gravity while fermenting?
« Reply #5 on: November 02, 2016, 12:28:22 AM »
I have spigots on all my fermenters, and have completely eliminated siphoning except for transferring wort from my kettle to the fermenter. I don't think that a spigot poses any danger of infection because the wort is flowing out of the fermenter,  not in. If a bug were to travel back thru the spigot and into the fermenter, then you have a leak in the spigot and wort on the floor.

I let all my beers sit in the fermenter for 2 weeks, then rack and bottle. If I am dry hopping, I add the hops and let it sit for another 5 to 7 days, rack to another fermenter with a spigot, and bottle. And believe it or not, I rarely if ever check final gravity.

Sent from my SAMSUNG-SM-G900A using Tapatalk


Offline Hand of Dom

  • Brewer
  • ****
  • Posts: 372
    • View Profile
Re: How to check gravity while fermenting?
« Reply #6 on: November 02, 2016, 09:55:44 AM »
I use a tap/spigot to take gravity samples, and to transfer to bottling bucket for batch priming.  It get a spray of starsan before and after sampling/transfer, and gets a soak in oxiclean after the batch is done.  I have a tap on my bottling bucket too which I apply the same regime to.
Dom

Currently drinking - Amarillo saison
Currently fermenting - Pale ale 1 - 2017

Offline JJeffers09

  • Senior Brewmaster
  • ******
  • Posts: 1121
    • View Profile
Re: How to check gravity while fermenting?
« Reply #7 on: November 02, 2016, 11:06:17 AM »
I have spigots on all my fermenters, and have completely eliminated siphoning except for transferring wort from my kettle to the fermenter. I don't think that a spigot poses any danger of infection because the wort is flowing out of the fermenter,  not in. If a bug were to travel back thru the spigot and into the fermenter, then you have a leak in the spigot and wort on the floor.

I let all my beers sit in the fermenter for 2 weeks, then rack and bottle. If I am dry hopping, I add the hops and let it sit for another 5 to 7 days, rack to another fermenter with a spigot, and bottle. And believe it or not, I rarely if ever check final gravity.

Sent from my SAMSUNG-SM-G900A using Tapatalk
You're experienced, he's not.  Checking final gravity is important when you first start out...

Sent from my SM-S820L using Tapatalk

"Beer is living proof that God loves us and wants us to be happy" - Benjamin Franklin

AHA Member
Indiana Brewers Union (IBU)

Offline majorvices

  • Global Moderator
  • I must live here
  • *****
  • Posts: 9636
  • Polka. If its too loud you're too young.
    • View Profile
    • Yellowhammer Brewing Company
Re: How to check gravity while fermenting?
« Reply #8 on: November 02, 2016, 11:12:40 AM »
Checking gravity while active fermentation is taking place can be tough. You will need to decarbonate by shaking as much as possible, then you may also need a drop of anti-foam. I would say for new brewers you really only need to check the beginning and when signs of fermentation are over or slowing. But for more advanced brewers taking gravity samples during fermentation may be necessary depending on what they are trying to achieve.

Offline EnkAMania

  • Assistant Brewer
  • ***
  • Posts: 169
    • View Profile
Re: How to check gravity while fermenting?
« Reply #9 on: November 02, 2016, 03:45:26 PM »
Some day we'll look back on this and it will all seem funny

Offline deadpoetic0077

  • Assistant Brewer
  • ***
  • Posts: 209
  • Noobie
    • View Profile
Re: How to check gravity while fermenting?
« Reply #10 on: November 02, 2016, 05:28:48 PM »
I use this http://tilthydrometer.com/products/brewometer

How has this been? I looked at this and the beer bug and looked like this one was the better choice overall. Does it automatically track? easy to use? Someone said you have to have a tablet or something with Bluetooth conntected to it and for it to be constantly on for it to track.

Offline EnkAMania

  • Assistant Brewer
  • ***
  • Posts: 169
    • View Profile
Re: How to check gravity while fermenting?
« Reply #11 on: November 02, 2016, 07:57:34 PM »
I use this http://tilthydrometer.com/products/brewometer

How has this been? I looked at this and the beer bug and looked like this one was the better choice overall. Does it automatically track? easy to use? Someone said you have to have a tablet or something with Bluetooth conntected to it and for it to be constantly on for it to track.

It works great.  If you want continuous monitoring, you'll need some bluetooth device(I have a tablet)  You can have it write to a spreadsheet in google docs.  A guy setup a website https://www.brewstat.us/ where I have my results go to. 
Some day we'll look back on this and it will all seem funny

Offline deadpoetic0077

  • Assistant Brewer
  • ***
  • Posts: 209
  • Noobie
    • View Profile
Re: How to check gravity while fermenting?
« Reply #12 on: November 02, 2016, 08:43:02 PM »
I use this http://tilthydrometer.com/products/brewometer

How has this been? I looked at this and the beer bug and looked like this one was the better choice overall. Does it automatically track? easy to use? Someone said you have to have a tablet or something with Bluetooth conntected to it and for it to be constantly on for it to track.

It works great.  If you want continuous monitoring, you'll need some bluetooth device(I have a tablet)  You can have it write to a spreadsheet in google docs.  A guy setup a website https://www.brewstat.us/ where I have my results go to.

Great! I may end up getting one of these. Makes it easier to track gravity and temp. Esp when I have to use a swamp cooler since I don't have space for a fridge!

Offline Stevie

  • Official Poobah of No Life.
  • *
  • Posts: 6858
    • View Profile
Re: How to check gravity while fermenting?
« Reply #13 on: November 02, 2016, 08:56:53 PM »
$120 is just too much considering it doesn't record values on its own. I'd be more interested at $75, and would maybe consider 3 for $240

Offline HoosierBrew

  • Global Moderator
  • I must live here
  • *****
  • Posts: 13030
  • Indianapolis,IN
    • View Profile
Re: How to check gravity while fermenting?
« Reply #14 on: November 02, 2016, 09:50:31 PM »
+1. I'm curious/skeptical about its accuracy as well, as it would read through krausen foam and CO2 bubbles. I guess if it at least is consistent enough to read steadily when you're at FG, that's something. But for that money I'd want a fair amount of accuracy.
Jon H.