Yeast Cleaning up Their Waste

[WiscoMan]

Everyone says to leave your beer in the primary for many weeks to allow the yeast to go and eat up their waste.

Will the yeast do this in the secondary and the bottles?

I had a large yeast cake in my secondary and I have some yeast on the bottom of my bottles so will the same thing happen for me in my bottles?

 

[Golddiggie]

It's better to let it do it in bulk, in primary. I would also advise being very selective about racking to a brite tank/second vessel for batches. Unless you have a valid reason (aging on something that works best OFF the yeast) then I wouldn't do it. IMO/IME racking to the brite tank is over-advised by stores that are using methods from 20+ years ago. Back when yeast wasn't nearly as good as it is today.

The sediment layer in your bottles is from bottle carbonating. It's produced by the yeast that's in suspension, when you bottle, that are woken back up by the priming solution.

BTW, it takes far longer for the yeast to bottle condition brews compared with leaving it all in primary. I don't move my brews from primary until they are ready to drink (just needing carbonation). IME, this produces more reliable results. I also don't bottle anymore, since moving to kegging. So, once a keg is filled, I just need to carbonate it up and it's ready to drink. No extended time needed to bottle condition it.

 

[TyTanium]

The yeast at the bottom don't seem to do much, it's the yeast still in suspension that are cleaning up. There's generally not much yeast activity in bottles to do much cleaning up, but some extra time conditioning may help, depending on the flaw. But oftentimes it doesn't.

The trick is to optimize your fermentation so there's not as much waste to clean up...done in days instead of weeks/months.

 

[inhousebrew]

The trick is to optimize your fermentation so there's not as much waste to clean up...done in days instead of weeks/months.

As always good advice on being nice to your yeast. Proper pitching rates and controlled lower fermentation temps can go a long ways to helping the product.

 

[WiscoMan]

That seems like the answer I was expecting. I feel that my beer turned out really well besides alot of gunk on the bottom of the bottles. Keeping them in the fridge for awhile before drinking will help this though.

I bottled 5 days ago. Should I stir up the bottles to get the yeast back in suspension?

 

[inhousebrew]

I bottled 5 days ago. Should I stir up the bottles to get the yeast back in suspension?

If it's carbonated and tastes fine there's no real reason to.

 

[Golddiggie]

The trick is to optimize your fermentation so there's not as much waste to clean up...done in days instead of weeks/months.

That's, very often, more than many 'new' home brewers are either able, or willing, to do. The first step is for them to actually understand what the above statement means. Then go about doing what it takes.

Steps include:
Providing the proper amount of O2 for the yeast for initial replication. Just shaking or pouring into fermenter, is vastly insufficient. Aquarium pumps take a long time to infuse the wort. Both of those max out at 8ppm, which can be ok for a low/moderate OG batch. But try to make something stronger/bigger and you're far short. At that point, only a pure O2 infusion system will do the job right.
Keeping the beer fermenting at the correct temperature range. This means keeping the contents of the fermenter at the right temperature. Ambient temperature is useless. Beer can ferment anywhere from 5-10F above ambient.
Provide the yeast with proper nutrition in the wort.
Pitch the correct amount of yeast cells for the batch size and OG. There are pitch calculation tools out there. Most common are Mr. Malty and yeastcalc. I use yeastcalc since it allows you to computer for up to three starter steps. Doing that, you can use far less DME to get the cell count needed for a batch. Using a stirplate for the starter also means you'll make smaller starters that are done/ready far faster.

Personally, I use a pure O2 infusion system comprised of an air stone on a stainless wand, 20 cubic foot O2 tank and regulator with a flow meter on it. The flow meter means I KNOW the O2 infusion rate. The regulators that go onto the O2 bottles you get from hardware stores have NO way for you to know what the flow rate is. IMO, that's worthless. I also make starters for ALL my brews, since I'm using liquid yeast. I'm also fermenting in the basement where I live, which is a great temperature for my ales to ferment at. I have a thermowell in each fermenter, so I KNOW what temperature the beer is fermenting at. No guessing, no using fermometers, and hoping you're getting it right. There are times I'll use a swamp cooler to get the temperatures where I need them, but [IMO] that's easy to do. It's also a cheap way to get the temperatures where they need to be.

 

[tgmartin000]

How did you do your thermowell?

 

[bovineblitz]

That seems like the answer I was expecting. I feel that my beer turned out really well besides alot of gunk on the bottom of the bottles. Keeping them in the fridge for awhile before drinking will help this though.

I bottled 5 days ago. Should I stir up the bottles to get the yeast back in suspension?

If you bottled 5 days ago, leave it alone for ~2 more weeks and it'll be good.

 

[helibrewer]

That's, very often, more than many 'new' home brewers are either able, or willing, to do. The first step is for them to actually understand what the above statement means. Then go about doing what it takes.

Steps include:
Providing the proper amount of O2 for the yeast for initial replication. Just shaking or pouring into fermenter, is vastly insufficient. Aquarium pumps take a long time to infuse the wort. Both of those max out at 8ppm, which can be ok for a low/moderate OG batch. But try to make something stronger/bigger and you're far short. At that point, only a pure O2 infusion system will do the job right.
Keeping the beer fermenting at the correct temperature range. This means keeping the contents of the fermenter at the right temperature. Ambient temperature is useless. Beer can ferment anywhere from 5-10F above ambient.
Provide the yeast with proper nutrition in the wort.
Pitch the correct amount of yeast cells for the batch size and OG. There are pitch calculation tools out there. Most common are Mr. Malty and yeastcalc. I use yeastcalc since it allows you to computer for up to three starter steps. Doing that, you can use far less DME to get the cell count needed for a batch. Using a stirplate for the starter also means you'll make smaller starters that are done/ready far faster.

Personally, I use a pure O2 infusion system comprised of an air stone on a stainless wand, 20 cubic foot O2 tank and regulator with a flow meter on it. The flow meter means I KNOW the O2 infusion rate. The regulators that go onto the O2 bottles you get from hardware stores have NO way for you to know what the flow rate is. IMO, that's worthless. I also make starters for ALL my brews, since I'm using liquid yeast. I'm also fermenting in the basement where I live, which is a great temperature for my ales to ferment at. I have a thermowell in each fermenter, so I KNOW what temperature the beer is fermenting at. No guessing, no using fermometers, and hoping you're getting it right. There are times I'll use a swamp cooler to get the temperatures where I need them, but [IMO] that's easy to do. It's also a cheap way to get the temperatures where they need to be.

^^^^ This! Happy yeast will reward you greatly. I use a ferm chamber since basements are scarce on the left coast.

 

[helibrewer]

How did you do your thermowell?

There are a number of SS thermowells that fit in a drilled stopper so they are suspended in the wort.

 

[bovineblitz]

That's, very often, more than many 'new' home brewers are either able, or willing, to do. The first step is for them to actually understand what the above statement means. Then go about doing what it takes.

Steps include:
Providing the proper amount of O2 for the yeast for initial replication. Just shaking or pouring into fermenter, is vastly insufficient. Aquarium pumps take a long time to infuse the wort. Both of those max out at 8ppm, which can be ok for a low/moderate OG batch. But try to make something stronger/bigger and you're far short. At that point, only a pure O2 infusion system will do the job right.
Keeping the beer fermenting at the correct temperature range. This means keeping the contents of the fermenter at the right temperature. Ambient temperature is useless. Beer can ferment anywhere from 5-10F above ambient.
Provide the yeast with proper nutrition in the wort.
Pitch the correct amount of yeast cells for the batch size and OG. There are pitch calculation tools out there. Most common are Mr. Malty and yeastcalc. I use yeastcalc since it allows you to computer for up to three starter steps. Doing that, you can use far less DME to get the cell count needed for a batch. Using a stirplate for the starter also means you'll make smaller starters that are done/ready far faster.

Personally, I use a pure O2 infusion system comprised of an air stone on a stainless wand, 20 cubic foot O2 tank and regulator with a flow meter on it. The flow meter means I KNOW the O2 infusion rate. The regulators that go onto the O2 bottles you get from hardware stores have NO way for you to know what the flow rate is. IMO, that's worthless. I also make starters for ALL my brews, since I'm using liquid yeast. I'm also fermenting in the basement where I live, which is a great temperature for my ales to ferment at. I have a thermowell in each fermenter, so I KNOW what temperature the beer is fermenting at. No guessing, no using fermometers, and hoping you're getting it right. There are times I'll use a swamp cooler to get the temperatures where I need them, but [IMO] that's easy to do. It's also a cheap way to get the temperatures where they need to be.

Shaking actually does appear to be both efficient and sufficient. With a higher OG it's not ideal, but for the most part it's quite good. A pump is pretty inefficient though, basically to the point of being useless.

http://llnw.libsyn.com/p/6/8/b/68bd...id=1452668&h=ac0d2420fbdce38b8769bdaf2146c68b

I personally use oxygen but would only recommend shaking or O2. Even with a regulator on your O2 to monitor flow rate, how do you know what rate is ideal (honest question here)?

My order of importance, from most to least is:

Temperature control
...
Pitch rate
Oxygen
...
Nutrients

For a newer brewer, they can kill a couple birds easily... use dry yeast (which I still do often), keep the gravity at or below ~1.065 and use the shaking method, and try to swamp cool.

I personally found swamp cooling to be terribly annoying so monitored craigslist for a mini fridge and scored one pretty quickly. IMO temp control is by far the most important piece of the puzzle.

 

[Krovitz]

I've read you need to be careful using straight O2 because too much can be toxic to yeast. I just use a sanitized paint stirrer on a drill to aerate. Works great, foams up fast. I use dry yeast, put bucket in cool corner, 3 weeks primary, 3 weeks bottled. Rdwhahb.

 

[Golddiggie]

How did you do your thermowell?

Since I ferment in adapted sanke kegs, I had them welded into drilled TC caps.

These are the 16" long thermowell's Brewer's Hardware sells.

bovineblitz, currently, my time and flow rate is based on experience with different OG ranges. BUT, I do plan on getting an actual dissolved O2 meter soon. Then I'll use documented sources for the O2 ppm needed for higher gravity worts in order to have enough O2 for the yeast to perform optimally. It's really not a matter of optimal flow rate, but the end results. I also plan on creating a document listing the batch OG, O2 LpM rate and duration and the dissolved O2 readings (once I have the meter). This way, I'll be able to reference it and know what I'll have for results without using the meter every time.

BTW, with my back, the shake method is 100% out. Besides, it's really only 'sufficient' for lower OG worts (under ~1.060). Also, you simply cannot get above 8ppm without using pure O2.

 

[Golddiggie]

I've read you need to be careful using straight O2 because too much can be toxic to yeast. I just use a sanitized paint stirrer on a drill to aerate. Works great, foams up fast. I use dry yeast, put bucket in cool corner, 3 weeks primary, 3 weeks bottled. Rdwhahb.

Where did you read that???

 

[AnchorBock]

Proper pitching rates, pure 02 and controlled fermentation temps = shorter primary. I rarely leave a beer (1.075 or under) in primary for more than 10 days at this point. If you don't have the aforementioned under control then get the beer to the point of only needing carbonation before bottling/kegging (2-3 weeks for most ales) as Golddiggie stated.

 

[Krovitz]

Where did you read that???

I think it was a BYO article on aeration. They were writing about all the different techniques.

 

[Krovitz]

Just skimmed through BYO article and it wasn't in there. I know I read that somewhere though. Apparently I am spreading misinformation.

 

[TyTanium]

Alternative to a thermowell is just taping the probe to the side of the fermentation vessel. Cover it with a towel or some insulation. The variance is negligible.

 

[nilo]

I have always been skeptical about the term "Yeast cleaning after themselves" that is commonly used by homebrewers.
Those that make this statement usually recommend leaving the beer in primary for 2 weeks or more after fermentation is completed (stable FG).
I have attached some info from White Labs on yeast life cycle.
From this article, the yeast life cycle has 3 stages:
1)Lag stage - 3 to 15h, yeast absorb minerals and prepare to process the sugars
2)Exponential growth stage - 1 to 4 days, yeast multiply and consume sugars at a rapid pace, high rausen, generates lots of CO2
3)Stationary stage - 3 to 10 days, small yeast growth, maturation, reabsorbing diacytyl, flocculation

So the "cleaning" process seems to happen at the end of the 3rd stage called stationary stage, when yeast activity has
reduced due to lack of sugars. This stage is also called "conditioning stage" and ends with a stable FG and with the yeast flocculation and drop/compacting to the bottom of the fermenter.
If that is the case, once FG is reach, there is no sense in leaving the beer in primary other than for clarifying purposes in the case of low flocculation strains that may require longer time.

If anyone can point to other documents that can add or propose different conclusions it would be great.

View attachment Yeast_Life_Cycle.pdf

 

[Golddiggie]

That's all well and good IF you have tight temperature control, pitch the correct amount of yeast, etc... So many homebrewers don't do that, or cannot do that.

The document didn't mention an OG range that information is valid for. A low OG batch WILL finish faster than a higher OG batch. Brew something at 1.040 and another at 1.080 and see how long they take under the exact same conditions. IMO, that information/time scale is only really valid for the lower OG batches (under 1.060), where you're also pitching the correct amount of yeast for the batch, and giving them enough O2 (in solution) to go to work.

I would advise brewers that cannot (or do not) control fermentation temperatures, infuse the wort with enough O2 for the batch, and pitch the correct amount of yeast, to give the batch more time. After you've actually established the FG has been reached (at least two matching SG readings 2-3 days apart) taste the sample to see how it is. IF you have ANY 'off' flavors, give it more time. Also, don't rack to another vessel until the brew is done. So many new brewers follow instruction sheets and move the brew far too soon. Also, make damned sure there's a valid reason to move the brew to a brite tank, or second vessel, before you do so. IMO, doing so for ales (or batches using ale yeasts) before the batch is 100% finished and ready for bottle/keg, is a bad idea.

 

[nilo]

I agree that these factors (OG, pitch rate, temp control, strain) will affect the profile of fermentation. I however imagine that most brewers do some type of temp control and OG's would be under 1.060.
Just found some more info, from Wyeast, that suggests that the conditioning/cleanning stage starts AFTER FG is reached, when flocculation starts until all yeast has dropped.
One thing though, some strains have a very short flocculation timing, like S04 as an example, so the actual time it is "cleanning" the beer may be very short, after FG is reached.
That may explain why, in my limited experience, S05 would produce cleaner taste beer since it takes much longer to drop and have more time to process the "waste".

"Fermentation

Fermentation is the heart of the brewing process. During fermentation, wort created from raw materials is converted to beer by yeast. Fermentation is usually divided into three stages: primary, secondary, and conditioning (or lagering). Fermentation is when yeast produce all of the alcohol and aroma and flavor compounds found in beer. Manipulation of temperature, oxygen levels, and pitch rate as well as yeast strain selection will all dramatically affect the production of aroma and flavor compounds produced during fermentation.

Primary Fermentation

The primary stage of fermentation begins when the yeast is introduced into cooled, aerated wort. The yeast quickly utilize the available oxygen to produce sterols, a vital compound for culture expansion. When the oxygen is gone, the yeast switch to the anaerobic phase where the majority of wort sugars are reduced to ethanol and CO2. Yeast growth occurs during primary fermentation. The extent and rate of yeast growth is directly related to the production of aroma and flavor compounds.

Primary Fermentation Summary:
• Depletion of dissolved oxygen
• Acidification / reduction in pH
• Yeast growth or culture expansion
• Ethanol and CO2 production
• Production of flavor compounds such as esters, diacetyl, sulfur containing compounds, etc.
• Consumption of most wort sugars

The temperature of the primary fermentation should be regulated according to the desired flavor and aroma profile. The following is a guideline:

Primary Fermentation Temperatures:
• Ales: 62°F – 75°F (17°C – 24°C)
• Lagers: 46°F – 58°F (8°C – 14°C) *Note: Lager fermentations can be started warmer (~60°F, 15.5°C) until signs of fermentation (gravity drop, CO2 production, head formation) are evident. Cool to desired fermentation temperature once signs of fermentation are observed.
• Wheat and Belgian styles: 62°F – 85°F (17°C – 29°C)

Secondary Fermentation

The secondary stage of fermentation refers to the stage of fermentation after the majority of the wort sugars have been consumed and there is a sharp decrease in the rate of fermentation. During this period, most of the final sugars are depleted and some secondary metabolites are converted by the yeast. Yeast flocculation and settling begins to occur due to the increase in alcohol content and the depletion of sugar and nutrients. Diacetyl reduction takes place during secondary fermentation and during the diacetyl rest that some brewers incorporate into the secondary stage of fermentation.

Secondary Fermentation Summary:
• Decreased rate of ethanol and CO2 production
• Diacetyl Conversion
• Reduction of some flavor compounds by yeast metabolism or CO2 scrubbing
• Terminal gravity is reached
• Yeast flocculation and settling begins

Secondary Fermentation Temperatures:
• Ales: Same as primary fermentation (higher temperatures will increase diacetyl reduction rates)
• Lagers: 40°F - 60°F (4°C - 15°C). Some brewers allow the beer to increase in temperature to speed the diacetyl reduction. This increased temperature is usually only sustained for 24 to 48 hours.
• Wheat and Belgian Beers: Same as primary fermentation (higher temperatures will increase diacetyl reduction rates).

Conditioning

The conditioning stage takes place when the terminal gravity has been reached and the tank is cooled to refrigeration temperatures (31°F - 38°F, 0°C - 3°C). During this time the yeast continues to flocculate and settle. The yeast also conditions the beer by reducing various undesirable flavor compounds. Ales do not benefit from long conditioning times like lagers do. The desirable flavors in ales will decrease with age and therefore it is recommended that conditioning be as short as possible before packaging. Exposure to oxygen at this stage is extremely detrimental to beer quality.

Conditioning Summary:
• Most of the yeast is removed from beer
• Formation and precipitation of haze forming proteins
• Reduction and mellowing of harsh flavors
• Reduction of sulfur compounds, diacetyl, and acetaldehyde
• Flavor stabilization
"

 

[Piratwolf]

. I however imagine that most brewers do some type of temp control....

"

While I agree generally that 2-week+ conditioning phases are probably over cautious (my beers generally go into the keg at 10-14 days after pitching yeast), your statement above is, IME, profoundly mistaken I'd you mean "effective" temp control.

 

[Golddiggie]

While I agree generally that 2-week+ conditioning phases are probably over cautious (my beers generally go into the keg at 10-14 days after pitching yeast), your statement above is, IME, profoundly mistaken I'd you mean "effective" temp control.

My current 'temp control' consists of monitoring the fermentation temperature of a batch to ensure it doesn't go higher than I want. Not difficult in the part of the basement I'm using. It wasn't as easy in my brew-buddy's basement due to the proximity of the furnace and other things.

 

[nilo]

My statement "some type of temp control" means:
-place a thermometer sticker on the side of a carboy and care about it, like moving the carboy around, setting on a bath tub with icy water, on a warmer spot in the house for those winter months. It is not "effective" as a fermentation chamber BUT it still helps and I still believe many brewers do that.