Gravity readings after 2 weeks in primary really necessary?

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Biscuits

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I am posting this in the beginners section because even though I have been brewing for a few years, it still seems like somewhat of a newbie question to me. BUT, I always see the advice of taking two hydrometer readings 3 days apart to verify whether your fermentation is complete, and I wonder...How often, if ever, is it not? I ask this while bearing in mind that I always leave my wort/beer in primary for 2 weeks regardless of OG.

Is this one of those antiquated methods that we still do blindly because of tradition? This day and age, with controlled production of brewing grains and yeast strains, is it really necessary? Don't get me wrong, I still take a reading before I bottle, but mainly to see where my beer ended up and calculate ABV as well as to see if there were any issues with my process that produced unfermentables.

Am I wrong to question this? I guess the old saying, "better safe than sorry" applies here...but how many of you, who ferment for longer than lets say a solid 7 days" have ever taken a reading and found that your beer (normal gravity range, 1.040-1.060'ish) was still fermenting?
 
Nope. I do it because I've had fermentation restart in the bottle. It is nearly effortless to take a reading, so why not do it?
 
Since each fermentation is different, I've had beers finish fermenting & settling out in 10 days flat. Others, in about 2 weeks, still others taking 3 weeks & a few days. I usually take an FG sample around 10 days or so, just to see where it's at. Some numbers 2-3 days later didn't match, so that tells me it's got some work to do yet. It's always good to use a hydrometer to test it to be sure it's done fermenting, as bottle bombs can be dangerous! So it's nothing antiquated, but rather proof of the pudding, so to say.
 
I've had English style yeasts never finish in 3 weeks (too cool maybe, who knows) and then overcarb in the bottles. By taking hydro readings, I knew "finishing" at 1.019 from 1.043 was unexpected. I've almost begun to wonder about doing Kaiser's fast ferment test from now on, then installing CO2 bubbler lines to rouse the yeast when it's not finishing up, then...then I relax.
 
Nope. I do it because I've had fermentation restart in the bottle. It is nearly effortless to take a reading, so why not do it?

Well, adding priming sugar causes that...but I am assuming you ended up with bottle bombs? This was after how long in primary before bottling? I am just playing Devil's advocate here because I personally have never had any issues.

Since each fermentation is different, I've had beers finish fermenting & settling out in 10 days flat. Others, in about 2 weeks, still others taking 3 weeks & a few days. I usually take an FG sample around 10 days or so, just to see where it's at. Some numbers 2-3 days later didn't match, so that tells me it's got some work to do yet. It's always good to use a hydrometer to test it to be sure it's done fermenting, as bottle bombs can be dangerous! So it's nothing antiquated, but rather proof of the pudding, so to say.

I can see bigger beers taking longer, naturally, but for a normal gravity beer, in my short experience, I have never had one not finish in the 2 weeks. Like I said, I am playing Devil's advocate and I still take readings at this point but have never had the need to leave it longer...maybe I am doing something wrong?
 
I've had English style yeasts never finish in 3 weeks (too cool maybe, who knows) and then overcarb in the bottles. By taking hydro readings, I knew "finishing" at 1.019 from 1.043 was unexpected. I've almost begun to wonder about doing Kaiser's fast ferment test from now on, then installing CO2 bubbler lines to rouse the yeast when it's not finishing up, then...then I relax.

This is an interesting point...I admit, I have not really ventured outside the proverbial box with yeast..I mainly use US-05 and US-04...So, maybe this practice will again prove itself necessary to me when I begin using more various yeast strains.
 
Personally, I don't ever take a sample from the fermenter to confirm it's done. To me, it's not worth the risk of infecting or oxidizing it. I don't care for the hassle either.

I monitor it over the first few days to make sure active fermentation starts and looks right. After a certain amount of time, the krausen drops, the beer beings to clear, it stops bubbling, etc. I package it after 2+ weeks depending on style and check the gravity then. I've never had one not finish right about where I thought it should (based on online calculators or kit instructions). Maybe it will bite me in the ass one day, but I'll take the risk for now.

I also try to do a good job oxiginating the wort, pitching enough yeast, and controlling the temperature. There's no reason the yeast shouldn't eat all their food in a relatively short amount of time if you're doing all that.
 
I personally don't take multiple readings after 3-4 days with most ales I start ramping the temps in my ferm chamber to 70° and let the beer sit at 70° for 2 more weeks or so.

Is this the best practice? Probably not, I can say i did have one beer that was not finished in 3 weeks and I didn't realize it until I went to bottle & took my FG reading as I was racking to the bottling bucket (the sample also tasted sweet), for a while after that I started taking two readings again, and then went back to only taking one....

For new recipes i will take 2 readings, sometimes.... but for recipes I am familiar with I usually only take one assuming, the FG is where i expect it to be

I do like to take multiple readings if I am trying to rush something like say taking a bottle conditioned IPA from grain to glass in a month
 
Well, adding priming sugar causes that...but I am assuming you ended up with bottle bombs? This was after how long in primary before bottling? I am just playing Devil's advocate here because I personally have never had any issues.



I can see bigger beers taking longer, naturally, but for a normal gravity beer, in my short experience, I have never had one not finish in the 2 weeks. Like I said, I am playing Devil's advocate and I still take readings at this point but have never had the need to leave it longer...maybe I am doing something wrong?

It was way more than an priming sugar issue. But you should do as you do if that works for you. I take a reading each time because it makes sense to me.
 
It also depends on how healthy the yeast pitch is, as well as temps involved. Whether the rehydrated yeast is at high krausen when pitched, within 10 degrees of current wort temp, or the starter being decanted & also within 10 degrees of wort temp. Besides temp control, or lack thereof & ambient temps. I've noticed that pitching the yeast re-hydrate, for instance, at high krausen caused far less lag time & finished quicker. Lack of that takes longer to finish & settle out. It's done when it's done, over & above 3-7 days to settle out clear or slightly misty after FG is reached.
 
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It also depends on how healthy the yeast pitch is, as well as temps involved. Whether the rehydrated yeast is at high krausen when pitched, within 19 degrees of current wort temp, or the starter being decanted & also within 10 degrees of wort temp. Besides temp control, or lack thereof & ambient temps. I've noticed that pitching the yeast re-hydrate, for instance, at high krausen caused far less lag time & finished quicker. Lack of that takes longer to finish & settle out. It's done when it's done, over & above 3-7 days to settle out clear or slightly misty after FG is reached.

I mainly use dry yeast, and pitch it as such, with no problems thus far..and I stress "thus far".
 
It also depends on how healthy the yeast pitch is, as well as temps involved. Whether the rehydrated yeast is at high krausen when pitched, within 19 degrees of current wort temp, or the starter being decanted & also within 10 degrees of wort temp. Besides temp control, or lack thereof & ambient temps. I've noticed that pitching the yeast re-hydrate, for instance, at high krausen caused far less lag time & finished quicker. Lack of that takes longer to finish & settle out. It's done when it's done, over & above 3-7 days to settle out clear or slightly misty after FG is reached.

"within 19" and "within 10"?
typo?
Do I need to adjust my highly inaccurate methods to include more measurements now?!?! (just kidding)
 
Just a typo, fixed it. My bad y'all. And in theory, re-hydrating dry yeast gives more cells than direct pitch, which can cause up to 50% attrition.
 
If it was strictly a beer quality issue, I wouldn't take the preliminary gravity sample because of possible contamination or oxidation. But since bottle bombs are a safety issue, I take the extra sample.

Thanks for bringing up this question. A little discussion about it is certainly a good thing.
 
It is nearly effortless to take a reading, so why not do it?

Depending on your setup. Getting the lids off my buckets is very, very difficult and while I'm attempting to get them off I'm worried that I'm either going to knock the whole bucket over or end up shaking/oxygenating it. I've only done a few brews so far, so I'm not expert, but I just wait at least two weeks and take a reading when I'm getting ready to bottle. As long as that reading is close to the FG called for in the recipe then I start bottling.
 
At least close can still give bottle bombs, depending on how much sugar you use in the priming solution. I have a tool that is used to pry the lids off buckets with. You can also get'em at home depot or other paint stores that're used to open 5 gallon paint buckets.
 
I use a refractometer to monitor completion of fermentation. The readings need to be corrected due to the presence of alcohol. But even without correction, if the readings are stable for three days, fermentation is either done or stuck. The corrected SG can tell you which case applies. I do this because you only need a fraction of an oz sample size, and I can grab this sample thru the airlock hole without removing the fermenter lid. Minimal chance for oxidation or infection. I use a long, sanitized plastic straw (my bottle filling wand with the spring valve removed) to take the sample.

Brew on :mug:
 
most ales for me I am drinking by 2 weeks but I keg

all the best

S_M

The worst that can happen if you keg too early is overly sweet beer. Bottling too soon can give you unstable glass grenades.

Brew on :mug:
 
The worst that can happen if you keg too early is overly sweet beer. Bottling too soon can give you unstable glass grenades.

Brew on :mug:

never had that problem ( overly sweet beer) I take gravity readings when a beer is done it is done and into the keg it goes

but you are right it can indeed lead to bottle bombs

all the best

S_M
 
I stopped doing multiple readings a long time ago on almost all brews - I keg 90% of them now but even before that. Once I got my fermentation practices figured out I just never saw anything that wasn't done by 10-14 days with the yeast dropped out. I guess I might be more careful if I was working with an unfamiliar or finicky yeast, or on something out of my comfort zone like a cider. I suppose I should also mention though that I don't have any small children in the house and I am SWMBO, so it's not like bottle bombs would be the end of the marriage or anything. ;)
 
I never take gravity readings at the end of fermentation! Going on 160 beers over the last 5-6 years. I take a reading before getting the wort into my carboy, pitch, dial in my temp in my chamber (66f 99% of the time) and leave the beer 3 weeks for most, sometimes 2 weeks for small beers, often 4-6+ weeks. I dry hop usually 5-7 days, raise the temp to 70 the last 3 days (sometimes,) crash cool the day before kegging. I'll take a reading when I keg just so I know the ABV. Never, not once, have I had a beer not be finished.

I use S-05 always, most beers finish 1.009-1.011.

Steve da sleeve
 
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