Jump to content
Mr.Beer Community
Spoodge

Can yeast ferment to fast

Recommended Posts

I just made an Irish Red Ale and made a yeast starter from a Nottingham dry yeast. I let it stir on my plate for two days before brewing the beer and adding it.  It was 1200 ml in size for a 5 gallon batch. once it was added to the beer it started making bubbles in the airlock within 3 hrs. My questions are this, is that normal to have fermentation that fast? Normally it takes a while to start bubbling.  Second question, what can happen as far as flavor because of fast fermentation.(better or worse) Can it happen too fast and give off flavors?  And was it over kill to make a starter from a dry yeast? 

 

Let the learning begin. 

Share this post


Link to post
Share on other sites
3 hours ago, Spoodge said:

I just made an Irish Red Ale and made a yeast starter from a Nottingham dry yeast. I let it stir on my plate for two days before brewing the beer and adding it.  It was 1200 ml in size for a 5 gallon batch. once it was added to the beer it started making bubbles in the airlock within 3 hrs. My questions are this, is that normal to have fermentation that fast? Normally it takes a while to start bubbling.  Second question, what can happen as far as flavor because of fast fermentation.(better or worse) Can it happen too fast and give off flavors?  And was it over kill to make a starter from a dry yeast? 

 

Let the learning begin. 

How many batches have you brewed so far? Seems like you may be doing some advanced things but not really understanding why

 

Is it normal to have a quick start to fermentation? If you give the yeast a good environment to do their job, then no.  You want a quick start.  The shorter the lag phase of yeast, the better off you are.  Bacteria have a hard time living in an alcoholic environment than a non alcoholic one. Ill get more into this on your last question

 

Will there be off flavors from a faster fermentation?  No.  Unless you had a rapid ferment due to a higher temperature which will cause fusel alcohol flavors.  It tastes like your beer is up in the 9% area.  Very much an alcohol warming taste.  Thats the unknown here, what was your ferment temp?  What was the gravity of your beer? Nottingham is notorious for being a fast fermenter. As long as you controlled your temps during the high krausen phase and before, youll be just fine.

 

Is it overkill to make a yeast starter for a dry yeast? Yes.  You see, to make yeast happy, you need to have enough of them to do the job.  That packet is designed for x amount of wort at y gravity.  Dry yeast also has nutrients in it to help your yeast be the best workers they can be.  The nutrients were all eaten up in the starter wort, however, you just increased your yeast army 10 times.  So really, you likely over pitched the amount of yeast cells to ferment your wort.  Not necessarily the worst thing, just kind of unnecessary. The amount of risk of contamination to make a starter and not to mention the effort, wasnt worth it for your batch.  Most would also say that at the price of dry yeast vs liquid yeast, you would be better off pitching two packs instead of trying to create more cells in a starter. Im also a firm believer in using yeast nutrient, that stuff is like gold!

 

Like I said, youre doing some very advanced things.  I applaud you for that but make sure you know the reasons why things need to be done.  I rarely even make starters for my liquid yeasts because they claim they have enough cells to do the job I ask them to.  However, if im brewing a beer for a competition, best believe Im gonna make a starter.  Nothing, nothing, I repeat, Nothing can replace the quality of the end product you get from a healthy batch of freshly propagated  yeast. But of course, sanitation, technique, and controlling the ferment are all very important also.

Share this post


Link to post
Share on other sites

Thank you for the reply. 

I am trying to read and understand and learn as much as I can about yeast as time allows. Which I’m learning is more of a science. So I really appreciate the time you took to answer my questions in detail.  I understand that fermentation temps are important to control because of phenols and esters and that they effect taste. So the next natural question is about high cell counts and their effect on fermentation. I figured that I overpicthed with a healthy yeast (I did use nutrient in my starter to feed them) and was considering what effect that may have had on taste. Unfortunately I dont normally take an OG or FG reading. I did once just to see how close I was, which was good. But now I’m wondering what effect does that have on yeast besides letting me know when fermentation is completed. I understand I would want to hit suggested OG And FG but not sure what effect it has on a beer,  and what effects does it have on taste as long as I’m close. Should I really be taking readings for other info beside completion of fermentation and alcohol % ? I normally give my brew 3 weeks in primary to finish fermentation and to clean up. Then bottle conditioning for 3 more weeks. 

 

 

Share this post


Link to post
Share on other sites

Overpitching of yeast can make the yeast lazy, and they go to sleep because there are too many of them to do the amount of work.  

 

There is zero reason to do a starter with dry yeast, and zero reason to use yeast nutrient.

 

There are 4 phases of yeast growth - Lag, Exponential growth, Stationary, and Decline.  If you overpitch, then during the lag phase yeast growth can be inhibited by the high pitch rates, which can result in more esters (yeast growth reduces the production of esters). 

 

You should go 3 weeks fermentation and 4 weeks in bottles, not 3.  Then at least 3 days in the frig.  

Share this post


Link to post
Share on other sites
1 hour ago, Spoodge said:

So the next natural question is about high cell counts and their effect on fermentation. I figured that I overpicthed with a healthy yeast (I did use nutrient in my starter to feed them) and was considering what effect that may have had on taste. Unfortunately I dont normally take an OG or FG reading. I did once just to see how close I was, which was good. But now I’m wondering what effect does that have on yeast besides letting me know when fermentation is completed. I understand I would want to hit suggested OG And FG but not sure what effect it has on a beer,  and what effects does it have on taste as long as I’m close. Should I really be taking readings for other info beside completion of fermentation and alcohol % ? I normally give my brew 3 weeks in primary to finish fermentation and to clean up. Then bottle conditioning for 3 more weeks.

 

Spoodge,

 

You questioned rather you overpitched or not.  Technically it is near impossible to overpitch on a homebrew level, but that doesn't mean you should just throw as much yeast at your wort as you can.  You said you started to get Krausen in 3 hours, not an issue as I have had fermentation start within 4 hours on many occasions in the past.  However, I found that the beer does suffer to a point when doing this and here is the reason.  Most of the character (desired flavors) from a particular yeast are put out in the lag phase and early fermentation.  This is the point when the yeast are preparing the army size to take on the task at hand.  When you pitch a level of yeast that doesn't require any real growth you take away that time for the yeast to produce these flavors.  If you were using US-05 then that isn't really an issue because that yeast is clean anyway.  You said you used Nottingham which is also fairly clean but it is an English strain so there are some low fruity esters that it will produce during this growth phase that will probably be lacking in your beer.  Being an Irish ale, you do want some of that character to come through. 

 

You also said that you don't take an OG or FG which I wouldn't recommend.  You can get by doing this but you are risking a fermentation that for some reason gets stuck and then you bottle and it restarts and BOOM (bottle bombs).  Also you didn't state if this was an extract beer or an all grain beer.  If it was extract then the recipe calculations should be within a point or 2 of actual OG.  But if it is an AG batch, there are a lot of factors in the mash that can contribute to the OG being off from where your recipe has it calculated.  In short, always take and OG and FG, it just makes you a better brewer.

 

Dawg

Share this post


Link to post
Share on other sites

I've now brewed a total of 10 different MRB batches.  On one, I pitched a 2nd packet of yeast, only because I had packets accumulating in the fridge from recipes which called for other yeasts than the MRB yeasts.  I'm not sure why I did, other than to use up some of the extra yeast I was accumulating.  I now realize I not only wasted the yeast, I may have inadvertently affected the beer's flavor.  I guess I'll know if I did when the conditioning phase ends and I taste the beer.  Fortunately, I only did that once.

 

I appreciate you sharing your knowledge on these matters, Dawg and Rick.

Share this post


Link to post
Share on other sites

There is a difference between using two packets of Mr. Beer yeast in a 2.13 gallon batch, and creating a starter from an 11.5g packet of yeast, with added yeast nutrients, to a 5 gallon batch.

 

People often use an entire 11.5g packet of yeast in a 2.5 / 2.13 gallon batch of beer.  

 

Think of it this way.  If you pitch a dry packet of yeast into wort, the yeast basically wake each other up and say "hey, time to go to work".

 

If you pitch an active starter, it's like a motorcross race where they're spinning their back wheels waiting for the bar to drop, and when it drops (pitched into wort), they're installing at top speed.  Then they look around and say "hey, there's so many of us, we won't fit through the turn, so I can slow down".  

 

Damn, that's a great analogy!   😁

Share this post


Link to post
Share on other sites

That is a very good analogy!! Really made me picture it in my head.

 

Let me try to sum this up for myself:

 

1. Making a starter from dry yeast is not necessary because they already have cell count and nutrients needed for a healthy fermentation and risks contamination. 

 

2. It’s better to give the yeast a “slight” lag time to create the desired flavors from that specific strain of yeast than to have “lazy” yeast from over pitching and not getting those flavors. 

 

3. Take gravity readings help you understand when the fermentation is completed to prevent bottle bombs and to give understanding of where the wort is in its fermenting stage. 

 

4. Fermentation temps are important and should be controlled for the specific yeast strains to control off flavors. 

 

Again I appreciate everyone and their input. Feel free to add more to this with your knowledge and opinions as it’s a forever learning experience. 

Share this post


Link to post
Share on other sites

Perfect.

 

Just note that you take the first gravity reading BEFORE pitching the yeast, and then future readings at the point where it makes sense, mostly right before "I'm ready to bottle".  Repeated gravity readings can satisfy your curiosity, but will deplete your beer by 3-4 ounces, and you never pour it back (except the initial reading if the hydrometer and tube are sanitized and you want to (I do).

Share this post


Link to post
Share on other sites

What a great topic. Theres a lot of info in this thread. Here’s what I think is important to take away from this all

 

3 hours ago, BDawg62 said:

 Most of the character (desired flavors) from a particular yeast are put out in the lag phase and early fermentation.  This is the point when the yeast are preparing the army size to take on the task at hand.  When you pitch a level of yeast that doesn't require any real growth you take away that time for the yeast to produce these flavors. 

 

3 hours ago, RickBeer said:

There are 4 phases of yeast growth - Lag, Exponential growth, Stationary, and Decline.  If you overpitch, then during the lag phase yeast growth can be inhibited by the high pitch rates, which can result in more esters (yeast growth reduces the production of esters). 

 

2 hours ago, RickBeer said:

Think of it this way.  If you pitch a dry packet of yeast into wort, the yeast basically wake each other up and say "hey, time to go to work".

 

If you pitch an active starter, it's like a motorcross race where they're spinning their back wheels waiting for the bar to drop, and when it drops (pitched into wort), they're installing at top speed.  Then they look around and say "hey, there's so many of us, we won't fit through the turn, so I can slow down".  

 And with that I believe we’ve rewritten the book on yeast. 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×