How long should i see signs of fermentation in a RIS?

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Donner

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This isn't a question about how long to leave my beer in primary, but rather, i'm curious how long a RIS will show signs of fermentation. My bucket seals tightly, so the airlock is my gauge for activity.

On sunday, I racked my 1.096 black chocolate stout clone onto a wlp001 yeast cake from a previous batch. The thing took off late that night and was bubbling away very aggressively until this morning. Now it's about every 3-4 seconds if not longer. I know big beers can stall out and i'd like to avoid that, so I'm just curious if i should get concerned if my airlock stops showing activity in the near future or if a RIS can ferment out in that short a period of time if enough yeast was present.

I hope that all make sense... thanks.
 

TipsyDragon

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dont use your airlock as a fermentation indicator it is very inaccurate especially with buckets. the only sign of the end of fermentation is the stabilization of your SG reading at your expected FG.
 

Revvy

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Your airlock is not a fermentation gauge, it is a VALVE to release excess co2. [/B]

If your airlock was bubbling and stopped---It doesn't mean fermentation has stopped.

If you airlock isn't bubbling, it doesn't mean your fermentation hasn't started....

If your airlock starts bubbling, it really doesn't matter.

If your airlock NEVER bubbles, it doesn't mean anything is wrong or right.

The only way to truly know what is going on in your fermenter is with your hydrometer. Like I said here in my blog, which I encourage you to read, Think evaluation before action you sure as HELL wouldn't want a doctor to start cutting on you unless he used the proper diagnostic instuments like x-rays first, right? You wouldn't want him to just take a look in your eyes briefly and say "I'm cutting into your chest first thing in the morning." You would want them to use the right diagnostic tools before the slice and dice, right? You'd cry malpractice, I would hope, if they didn't say they were sending you for an MRI and other things before going in....

Thinking about "doing anything" without taking a hydrometer reading is tantamount to the doctor deciding to cut you open without running any diagnostic tests....Taking one look at you and saying, "Yeah I'm going in." You would really want the doctor to use all means to properly diagnose what's going on. It's exactly the same thing when you try to go by airlock....

This is the only "sign of fermentation" you should be going by.....

 

Edcculus

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I'm still a fan of a quote from BYO late last year. Here is my paraphrased version:

Egg timers are great, but there is no such thing as a beer timer. A great chef doesn't use a timer to cook a steak does he? No, he uses use his senses, and ultimately a thermometer to check for the correct level of doneness. In brewing, the hydrometer is your tool to check for doneness.
 
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Donner

Donner

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wow, thanks guys, but really, i said i wasn't using it as an indication of final gravity. As i said above, i am merely curious how many days an airlock will show activity with a big beer. I don't generally take any readings for a month (but when i do, i do use my hydrometer. learned that one on the first batch).

My question was would a big beer cease visible activity within a few days or would it have a steady fermentation over a longer period of time because of the increased amount of sugar. I know there is no purpose in checking gravity while i'm having airlock activity.

Again, thanks for the replies but i really didn't need the lecture. Sorry if i wasn't clear that i am just curious about the differences in visible signs of fermentation between average beers and big beers.
 

MattHollingsworth

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For me, in my system, pitching the amount of yeast you did, with that gravity, what you have going on sounds totally normal. Don't start worrying. If you pitched that much yeast and are holding the temp steady, it will finish its job when it finishes its job. Let it finish up. Nothing to worry about here.
 

Edcculus

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My question was would a big beer cease visible activity within a few days or would it have a steady fermentation over a longer period of time because of the increased amount of sugar. I know there is no purpose in checking gravity while i'm having airlock activity.
In my experience, there is really no way of telling. Its very dependent on pitching rate, oxygen, and temp so giving a timeline is pretty much impossible.
 

Revvy

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My question was would a big beer cease visible activity within a few days or would it have a steady fermentation over a longer period of time because of the increased amount of sugar. I know there is no purpose in checking gravity while i'm having airlock activity.
Every situation is different as is ever recipe, temp/ ingredients/yeast/different fermentables all affect how long something is going to take and what is going to happen. And there are variables that affect airlock activity- changes in ambient temp, heck even your cat or child bumping into your fermenter can either stop or start the airlock bubbling in mid fermentation, or even in secondary- You beer could be happily sitting in secondary for months, NOT bubbling, and you hit it with the vacuum cleaner and suddenly release a bunch of co2 from the trub at the bottom, and it starts bubbling.

Even after a few days of high bubbling in the airlock and active fermentation, the airlock will wind down and stop, as the need to vent excess co2 decreases, but that doesn't mean that there's still not a couple more weeks of slow fermentation still needing to be done.

We're not trying to preach or lecture, we're just trying to point out that there are a ton of variability in airlocks, and that's why it's not a good idea to rely on them.
 
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