Prevent oxygen during cold crash

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njohnsoncs

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I want to do a cold crash in my primary fermentation bucket. I'm expecting that as it cools it will suck in oxygen (through the airlock). Is there a good way to prevent this? I would put it in a keg but I don't have an extra one.
 

JONNYROTTEN

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Ferment in a chest freezer where the chamber becomes filled with co2 then you sucking back in the co2....very unscientific but your cant stick your head in the chamber without an instant "holy sh*t" brain pain....I've done that and fermented in my living room and cold crashed without the co2 in the chamber and never noticed a bit of difference in the beer
 

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I would not be very overly concerned about it, but would keep it in mind. I don't really think that much oxygen is sucked back in and haven't seen any studies on this. But, given the size of the harvester in the previous picture, it must not be much.

If you are worried about oxygenation, it has been said that O2 would tend to float on top of the CO2 in the fermenter after a while. Although, I have always wondered how much it really does separate and how long it takes. I view this as more anecdotal. If CO2 really does separate, why isn't there a layer of it on the ground around us or in an enclosed, stagnant room.

When kegging or bottling you can mitigate this by careful transfers to your keg or bottles and purging the headspace of either with CO2. I flood the tops of bottles with CO2 from one of my tanks before I cap them and bleed my keg headspace 14 or 15 times.

I ferment in a freezer chamber which, as was mentioned by JohnnyRotten, is full of CO2 after fermentation, so for me, it isn't a big deal when crashing.

If you do leave the airlock on, I would make sure that it has only the minimum possible amount of liquid in it, so it doesn't get sucked back. Fill it just enough to cover the slots in the float. Instead of water or sanitizer some brewers use vodka, just in case. I have also seen people put a balloon (sanitized) on the airlock tube towards the end of fermentation. It expands and collects CO2 which is then sucked back into the fermenter during crashing. You would have to have a pretty tight fermenter for this to work.

You can create or purchase a CO2 harvester, but to me that seems like overkill.

Cheers!
RDWHAHB.
 

VirginiaHops1

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Although, I have always wondered how much it really does separate and how long it takes. I view this as more anecdotal. If CO2 really does separate, why isn't there a layer of it on the ground around us or in an enclosed, stagnant room.
CO2 is heavier and in a vacuum they should separate. The problem is it doesn't take much for gases to diffuse(mix), which is why they mix in our atmosphere. And when you open your fermenter or have pressure sucking air in during a cold crash.

I think whether it matters depends on a lot of things. What kind of beer you're making, how fast you're going to drink it, how sensitive your palate is to off-flavors, etc
 

mongoose33

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CO2 is heavier and in a vacuum they should separate. The problem is it doesn't take much for gases to diffuse(mix), which is why they mix in our atmosphere. And when you open your fermenter or have pressure sucking air in during a cold crash.

I think whether it matters depends on a lot of things. What kind of beer you're making, how fast you're going to drink it, how sensitive your palate is to off-flavors, etc
This won't happen. There's a sort of myth/belief out there that CO2 will form a blanket on beer, but it simply doesn't happen. I speculate that this idea comes from people seeing dry ice sublimate and flow downward (which is apparently in fact just water vapor doing that), so they assume it's heavier and thus forms a blanket.

So what they're seeing is cold water vapor (and presumably CO2) flowing down. But once the temps equalize, the gases mix. No blanket of CO2.

There are some posts here somewhere that show what happens when gases mix. Pretty convincing.
 
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mongoose33

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Use a CO2 harvester such as this, or save money and make your own.

View attachment 612460
You can do the CO2 harvester as noted above, but you have to be sure you have enough capacity. I've found quart jars were not sufficient in headspace to do this, plus if there's any kind of leak at all, they won't work.

What I've done in the past is take a bread bag and attach it to the airlock; as fermentation proceeds, it'll inflate the bread bag with CO2. Leave the attachment just loose enough that the excess can bleed out. When fermentation is about complete and before crashing, tighten down the connection to the airlock; now, as you crash and the headspace contracts, it'll draw in CO2 from the bag.

Here's a commercial version of what I'm referring to:

https://www.brewhardware.com/product_p/ccguardianv2.htm

Here's the bread bag version:

breadbag.jpg
 

JONNYROTTEN

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You can do the CO2 harvester as noted above, but you have to be sure you have enough capacity. I've found quart jars were not sufficient in headspace to do this, plus if there's any kind of leak at all, they won't work.

What I've done in the past is take a bread bag and attach it to the airlock; as fermentation proceeds, it'll inflate the bread bag with CO2. Leave the attachment just loose enough that the excess can bleed out. When fermentation is about complete and before crashing, tighten down the connection to the airlock; now, as you crash and the headspace contracts, it'll draw in CO2 from the bag.

Here's a commercial version of what I'm referring to:

https://www.brewhardware.com/product_p/ccguardianv2.htm

Here's the bread bag version:

View attachment 612540
I have a question. Is the suck back so severe that it actually sucks air, whether its co2 or oxygen INTO the beer? Or is it just moving the air around above the beer? If it's not actually sucking the air into the liquid essentially carbing the beer while it sits there there then does it really matter to begin with?

If it doesn't have the force to infuse the beer, then I highly doubt it makes a difference anyway unless your entire process from start to finish is void of Oxygen.

If its not infusing the beer than its just another couple days the beer is sitting there post fermentation that everybody does
 

mongoose33

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I have a question. Is the suck back so severe that it actually sucks air, whether its co2 or oxygen INTO the beer? Or is it just moving the air around above the beer? If it's not actually sucking the air into the liquid essentially carbing the beer while it sits there there then does it really matter to begin with?

If it doesn't have the force to infuse the beer, then I highly doubt it makes a difference anyway unless your entire process from start to finish is void of Oxygen.

If its not infusing the beer than its just another couple days the beer is sitting there post fermentation that everybody does
You're exposing the surface of the beer to a certain amount of oxygen. How much you wish to do that is up to you. I like to think of it this way: when people make starters they are trying to get oxygen into the wort. They might shake the flask, might use a stir plate, but during the process one is supposed to keep a loose lid on the flask so there's oxygen exchange.

(BTW, after the yeast in the starter is done and goes dormant, typically the starter keeps spinning and there still is oxygen exposure even though the "beer" is done. It's an argument for decanting off what presumably is oxidized beer. I've chewed on this one for a while, as my standard procedure is to dump the whole starter into the fermenter, no decanting. The beer is great, so whatever oxidation flavors might obtain from doing that appear to be limited).

I've followed the philosophy of doing everything I can to limit oxygen exposure in my beer. I don't want this to become a LODO threadjack, but the argument in those circles is it doesn't take a lot to screw up both the flavors as well as the shelf life of the beer--especially if it's a hoppy beer.

YMMV.
 

anteater8

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You can do the CO2 harvester as noted above, but you have to be sure you have enough capacity. I've found quart jars were not sufficient in headspace to do this, plus if there's any kind of leak at all, they won't work.

What I've done in the past is take a bread bag and attach it to the airlock; as fermentation proceeds, it'll inflate the bread bag with CO2. Leave the attachment just loose enough that the excess can bleed out. When fermentation is about complete and before crashing, tighten down the connection to the airlock; now, as you crash and the headspace contracts, it'll draw in CO2 from the bag.

Here's a commercial version of what I'm referring to:

https://www.brewhardware.com/product_p/ccguardianv2.htm

Here's the bread bag version:

View attachment 612540
I've been researching solutions to this problem for a while now. I was really surprised to learn that 1 to 2 liters of air can get sucked back into the carboy, and that the masons jars used in the co2 harvester setup are probably not big enough to prevent oxygen from getting in.

The bag/balloon solution seems much more simple and effective to me. I would have bought the product you linked, but its out of stock. Instead I bought a 25 pack of 18 inch mylar balloons off amazon for $10, and I'll be testing it out on my next IPA.
 

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I have a question. Is the suck back so severe that it actually sucks air, whether its co2 or oxygen INTO the beer? Or is it just moving the air around above the beer? If it's not actually sucking the air into the liquid essentially carbing the beer while it sits there there then does it really matter to begin with?

If it doesn't have the force to infuse the beer, then I highly doubt it makes a difference anyway unless your entire process from start to finish is void of Oxygen.

If its not infusing the beer than its just another couple days the beer is sitting there post fermentation that everybody does

The couple of days the beer is sitting there with some percentage of oxygen in the headspace is enough to do noticeable damage depending on what your threshold is. Anecdotally, most of my beers had noticeable flaws withing a week or two of kegging before I adopted a 100% oxygen free process on the cold side. In the most extreme case, brewing NEIPA, it was hard failures and dumpers. After adopting the pressure transfer process and using a cold crashing CO2 bladder system, boom, gold medal NEIPA.
 

Dgallo

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I would not be very overly concerned about it, but would keep it in mind. I don't really think that much oxygen is sucked back in and haven't seen any studies on this.
.
The negative pressure created will suck in huge amounts of o2 to equalize itself. This has an impact on all styles, but hoppy styles will see catastrophic effects.
I want to do a cold crash in my primary fermentation bucket. I'm expecting that as it cools it will suck in oxygen (through the airlock). Is there a good way to prevent this? I would put it in a keg but I don't have an extra one.
Do you have a co2 tank? If so your co2 line should be the perfect diameter to fit in your airlock hole. Remove your ball lock or pinlock fitting from you gas line. Slide the gas line into your fermenter, should be tight but will go. First purge your head space of your ferementer. Once it’s purged, set the gas to 2-3 psi and start your cold crash. As the pressure changes and begins to suck, your tank will equalize it with co2. This will eliminate your o2 there.

Keep in mind that you’re going to have oxygen issues already by racking it into your bottling bucket and then to the bottles. Also the neck of your bottle will hold o2. So when the yeast start carb conditioning the beer, oxygen will also be forced into the beer. However doing what I stated above will eliminate your biggest threat of 02
 

Dgallo

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You're exposing the surface of the beer to a certain amount of oxygen. How much you wish to do that is up to you. I like to think of it this way: when people make starters they are trying to get oxygen into the wort. They might shake the flask, might use a stir plate, but during the process one is supposed to keep a loose lid on the flask so there's oxygen exchange.

(BTW, after the yeast in the starter is done and goes dormant, typically the starter keeps spinning and there still is oxygen exposure even though the "beer" is done. It's an argument for decanting off what presumably is oxidized beer. I've chewed on this one for a while, as my standard procedure is to dump the whole starter into the fermenter, no decanting. The beer is great, so whatever oxidation flavors might obtain from doing that appear
YMMV.
Instead of decanting, pitch your starter while it’s highly active. People refer to this as krausening. This way your yeast are active, producing co2, and consuming the oxygen in the starter. It will also give you a healthier fermentation and produce the desirable esters for the yeast and lessen the formation of aceldatyhide and VDK
 

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Instead of decanting, pitch your starter while it’s highly active. People refer to this as krausening. This way your yeast are active, producing co2, and consuming the oxygen in the starter. It will also give you a healthier fermentation and produce the desirable esters for the yeast and lessen the formation of aceldatyhide and VDK
Slipping a little off topic but that isn't exactly what krausening is. Krausening is adding actively fermenting wort to post fermented beer intended to initiate conditioning and or carbonation. I guess you meant "pitch the starter at high krausen".

Incidentally, I wouldn't do that. Starter wort tastes awful.
 

Dgallo

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Slipping a little off topic but that isn't exactly what krausening is. Krausening is adding actively fermenting wort to post fermented beer intended to initiate conditioning and or carbonation. I guess you meant "pitch the starter at high krausen".

Incidentally, I wouldn't do that. Starter wort tastes awful.
Krausening is pitching active wort. You can condition kegs or brights with it if you choose, or start a fermentation with it.

Idk what you use as a starter or how big your starters are. But your starter most likely doesn’t taste good to you because it has yeast and the off flavors they produce before they clean themselves up. If your doing a 1l starter, Your starter is only 1/20 to 1/24 of your total post kettle volume. Also why stop the yeast from doing what their doing, make them stall out by cold cashing and then have them re activate themselves. But to each their own man.
 

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Instead of decanting, pitch your starter while it’s highly active. People refer to this as krausening. This way your yeast are active, producing co2, and consuming the oxygen in the starter. It will also give you a healthier fermentation and produce the desirable esters for the yeast and lessen the formation of aceldatyhide and VDK
I'm laughing.

That's exactly what I do. I haven't decanted a starter since about the 3rd time I ever made one.

BTW, I think krausening is actually pitching active yeast later in the fermentation, not at the outset.

********

I do one other thing that is rare; I've only run across maybe 2 or 3 people on HBT who do it too. That is, I oxygenate the starter wort before pitching the yeast into the flask.

My reasoning has been that we're driving off the O2 when boiling a starter (btw, that's one of the techniques of LODO brewing, preboil the strike water for 5 minutes to deoxygenate it). I thought about that a bit, wondering why I'd pitch good yeast into a starter devoid of oxygen. Couldn't think of a reason why that made sense, so I started oxygenating the starter wort.

I believe I have a much faster and more vigorous starter and that the yeast are going to be more effective in reproducing. When I pitch that starter into the oxygenated wort in my fermenter, I typically have active fermentation within 3-6 hours.

Even with a starter that seems to have finished, it takes off faster for me. I'm usually looking to pitch that starter after about 15-17 hours on the stir plate, at what seems to be the height of activity. I'll try to match temps between starter and wort exactly so as to not shock the yeast at all.

But Sunday I pitched a starter that had been on the stir plate for 28 hours and had stopped active fermentation; it still was bubbling away within 6 hours.
 

Dgallo

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I don’t buy into hotside LODO at all. To each their own though. I’m with you, I constantly aerate my starter.You would aerate your wort prior to pitch, starter would be the same in my opinion. I run my starter for 16-24 tops. Then it all goes in. Did that this week with a milkshake ipa, og of 1.072 on Tuesday, this morning 1.014. Now the fun begins. Puréed mango, pineapple and peaches going in with lactose today and have a tincture of vanilla beans going in at kegging
 

Dgallo

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Just a little krausening info
8AF74FC7-F402-4AD4-ADB2-B9E2C7D9D338.png
 

mongoose33

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Slipping a little off topic but that isn't exactly what krausening is. Krausening is adding actively fermenting wort to post fermented beer intended to initiate conditioning and or carbonation. I guess you meant "pitch the starter at high krausen".

Incidentally, I wouldn't do that. Starter wort tastes awful.
This is the sort of balancing act we always have to do.

I've come down on the side of promoting the most vigorous and fast-to-start fermentation I can get, and pitching an active starter does that for me.

I've tasted starter wort and I agree with you--it sure doesn't taste very good. But that got me to wondering: If I brew a simple smash recipe using only DME and a hop, shouldn't that also taste terrible?

And when people add DME to a recipe and the yeast work on that, shouldn't they be producing the same bad flavor?

I submit there's something else going on here, either the starter hasn't had time to condition (which it almost never has), or the yeast clean up after themselves given enough time, or the beer would taste much better if it were cold and carbonated.

Anyway, I figure the resulting starter is no different than a large fermentation in which people are using part or all DME as the source of their fermentables. And so I pitch the whole starter in. I have friends who want to buy my beer ($10/six pack, i.e., commercial prices), and a local bar owner who wants to sell my beer. I'm not licensed so that doesn't happen--looking into it--but if that starter is so bad, I can't see it in the results.

YMMV.
 

Dgallo

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This is the sort of balancing act we always have to do.

I've come down on the side of promoting the most vigorous and fast-to-start fermentation I can get, and pitching an active starter does that for me.

I've tasted starter wort and I agree with you--it sure doesn't taste very good. But that got me to wondering: If I brew a simple smash recipe using only DME and a hop, shouldn't that also taste terrible?

And when people add DME to a recipe and the yeast work on that, shouldn't they be producing the same bad flavor?
Well The starter is slightly different. There is a much higher ratio of yeast to volume, so just the flavor of the yeast would make it taste unpleasant. DME should is converted by the yeast the same way LME and all-grain wort would be, so I wasn’t trying to claim the off flavor is a resort of that. The off flavor comes typically early in fermentation. While the yeast begin wake up and eat, they don’t convert the sugars directly to alcohol, sometimes they convert it to acedaltihyde and/or VDK. As they continue to eat, they will reconsume this negative by products and then properly convert them to alcohol. That’s why you should do a 48-72 hour rest following hitting final gravity. Now with a starter, they don’t have the time to clean it up before you pitch it(don’t worry, they will clean it up when it’s fermenting your beer) and that’s why your starter can taste off.
 

mongoose33

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Well The starter is slightly different. There is a much higher ratio of yeast to volume, so just the flavor of the yeast would make it taste unpleasant. DME should is converted by the yeast the same way LME and all-grain wort would be, so I wasn’t trying to claim the off flavor is a resort of that. The off flavor comes typically early in fermentation. While the yeast begin wake up and eat, they don’t convert the sugars directly to alcohol, sometimes they convert it to acedaltihyde and/or VDK. As they continue to eat, they will reconsume this negative by products and then properly convert them to alcohol. That’s why you should do a 48-72 hour rest following hitting final gravity. Now with a starter, they don’t have the time to clean it up before you pitch it(don’t worry, they will clean it up when it’s fermenting your beer) and that’s why your starter can taste off.
That was the point of my post. I presume you're agreeing with it?
 

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Mongoose makes a great point that I think lots of people overlook:
If you boil your starter wort, you remove all dissolved oxygen from it in as little as 5 minutes of boiling.
If you don't oxygenate your starter, you are putting the yeast in an oxygen-deficient environment.
 

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Back to the original question though.

I don't see this being discussed, but the single most foolproof way to eliminate any suckback of airlock material or oxygen is to have your beer carbonated before you cold crash.

And the single best way to do that without adding an iota of oxygen on the cold side, is spunding.

In case you are not familiar with spunding, you transfer your beer to the serving keg with a few (around 4) gravity points left and let it naturally condition in the keg. It's kinda like adding sugar for bottle conditioning, but you don't have to add anything - you just use the sugar already in the beer.

Give it a few days to finish out, then cold crash your sealed, carbonated keg of beer.

The downside if you want fast turnaround is that it takes a little linger for the residual yeast and stuff to settle, and if you don't want to suck up that yeast for your first few pints, you will need something like a floating dip tube (like a CLearBeer system).

But, you will have zero oxygen exposure and don't have to fiddle with balloons, bags, or multi-jar apparati.
 

Dgallo

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I don't want a thread derail here, but unless you've done it, or tasted the results of it, there really isn't any basis for having an opinion.
The styles I brew, LODO would not show its self regardless. IPAs, sours, and stouts. My opinion is valid based on Brewing practices, the mash needs recirculating or at the least stirring and yeast need oxygen. But like I said to each their own
 

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The styles I brew, LODO would not show its self regardless. IPAs, sours, and stouts. My opinion is valid based on Brewing practices, the mash needs recirculating or at the least stirring and yeast need oxygen. But like I said to each their own
OK, so you don't understand it, I get that. Somehow you think mash recirculation invalidates LODO, which of course if you do it right, it doesn't. As to whether it matters with IPAs, stouts and sours, well, you don't have any idea. I know about brewing practices, too.

**********

As to oxygen, just to keep this on track: Oxygen prior to the boil? Not good. Unless you want your malt flavors oxidized. A little of that can be mitigated by a larger grain bill.

After chilling post-boil? Oxygen is needed by yeast. Whether that's already provided by the manufacturer in the way dry yeast is produced, or added via shaking, aerating w/ air, or oxygenating w/ pure oxygen, either way yeast need it for yeast health and reproduction.

Can beer be produced under less-than-optimal oxygen circumstances? Yes. People do it all the time. Some of it can even be pretty decent-tasting beer. If one wants the best beer that can be produced under their setup and circumstances, though, paying attention to this is important.

**********

As to vigor in fermentation taking off, just to add this to the discussion: my son is a microbiologist. PhD in it, in fact. He also brews, so I rely on his understanding of what's going on microbially to inform my own brewing practices.

He's commented that almost every beer is "infected," at least at the outset. Dust floating around has bacteria on it. Dust will almost certainly get into your wort. Ergo, infected. Thus, the name of the game is to get the yeast going as quickly as possible so it can outcompete that bacteria, which doubles in good environments as quickly as every 20 minutes. I want as little lag time as feasible so that the yeast can beat the bacteria.
 

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I'm laughing.

That's exactly what I do. I haven't decanted a starter since about the 3rd time I ever made one.

BTW, I think krausening is actually pitching active yeast later in the fermentation, not at the outset.

********

I do one other thing that is rare; I've only run across maybe 2 or 3 people on HBT who do it too. That is, I oxygenate the starter wort before pitching the yeast into the flask.

My reasoning has been that we're driving off the O2 when boiling a starter (btw, that's one of the techniques of LODO brewing, preboil the strike water for 5 minutes to deoxygenate it). I thought about that a bit, wondering why I'd pitch good yeast into a starter devoid of oxygen. Couldn't think of a reason why that made sense, so I started oxygenating the starter wort.

I believe I have a much faster and more vigorous starter and that the yeast are going to be more effective in reproducing. When I pitch that starter into the oxygenated wort in my fermenter, I typically have active fermentation within 3-6 hours.

Even with a starter that seems to have finished, it takes off faster for me. I'm usually looking to pitch that starter after about 15-17 hours on the stir plate, at what seems to be the height of activity. I'll try to match temps between starter and wort exactly so as to not shock the yeast at all.

But Sunday I pitched a starter that had been on the stir plate for 28 hours and had stopped active fermentation; it still was bubbling away within 6 hours.
If you are worried about oxygen in your finished beer then pitching the whole starter is not ideal. Also using pure O2 to oxygenate your starter wort is unnecessary, if you use a stir plate.

A stir plate constantly introduces oxygen into the starter wort, feeding it the oxygen it needs to obtain healthy yeast propagation. That is the reason for it (propagation), not beer. A stir plate more than doubles the yeast production as opposed to shaking it once in a while. But, one of the side affects of this process is that in addition to nice healthy yeast, you now have a lot of oxygenated, bad tasting, starter beer. You are better off decanting it (cold crashing it first if you have time) and keeping that away from your finished product. I figure the starter is for good yeast, the fermenter is for good beer, I would not pour starter liquid into my beer (I try to get rid of most of it). I do pour the starter beer into another sterile container and let it settle for a couple more weeks, to get the yeast that was still in suspension. I'll freeze this if there is enough (most of the time) or use it to propagate more.
 
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mongoose33

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If you are worried about oxygen in your finished beer then pitching the whole starter is not ideal.
We're going to have to disagree on this; I'm not pitching into the finished beer, I'm pitching into the just-created wort. Any oxygen in the starter is simply going to be used by the yeast as it multiplies in the fermenter, no differently than the oxygen that I'm putting into the wort using an oxygen tank and an aeration stone on a wand.

Also using pure O2 to oxygenate your starter wort is unnecessary, if you use a stir plate.
A lot of people argue this, and I don't know why. That wort in the starter begins almost devoid of oxygen; it's been boiled off, which is something the LODO people do to deoxygenate strike water prior to doughing in.

******

Can you produce beer without oxygenating the starter? Sure. I used to do exactly that, before I began to look into the LODO stuff. I began to wonder why I would want to pitch yeast into a starter wort that was devoid of oxygen.

I couldn't think of a reason why that made sense, as the yeast have to wait until the stir plate brings in oxygen, though how quickly that happens isn't clear.

A stir plate constantly introduces oxygen into the starter wort, feeding it the oxygen it needs to obtain healthy yeast propagation. That is the reason for it (propagation), not beer. A stir plate more than doubles the yeast production as opposed to shaking it once in a while. But, one of the side affects of this process is that in addition to nice healthy yeast, you now have a lot of oxygenated, bad tasting, starter beer. You are better off decanting it (cold crashing it first if you have time) and keeping that away from your finished product. I figure the starter is for good yeast, the fermenter is for good beer, I would not pour starter liquid into my beer (I try to get rid of most of it). I do pour the starter beer into another sterile container and let it settle for a couple more weeks, to get the yeast that was still in suspension. I'll freeze this if there is enough (most of the time) or use it to propagate more.
Again, we have to disagree here. A stir plate might or might not be the best way to introduce oxygen; I'm not sure why anyone would oppose the idea of adding oxygen directly so as to get the yeast going as quickly as possible.

***********

As to the starter wort tasting badly, well, that's true; however, it's not carbonated, not conditioned, the yeast hasn't had any time to clean up after itself, and most interesting of all, when people add DME into a wort, they're setting up exactly the same thing, i.e., yeast will convert DME to alcohol. What's different? Nothing I can see.

Now, it's possible there's something here I'm not seeing, as I don't know everything there is to know about brewing, but I cannot see where this is a bad idea, and I can see a lot of reasons why it's a good idea.

***********

I've noted above in this thread the advantage to a fast takeoff of yeast: it has the best chance of outcompeting any nasties that get into the wort.

The same could be said for starters.

Now, if you don't want to believe any of this, that's fine. You can do what you want, and it won't have any effect on my beer. And I'll do what I want, and do that knowing that I've had friends who want to buy my beer, produced with my starter protocol, at commercial prices, and a local person who wants me to brew so she can sell my beer in her bar.

I am thinking that if what I do is so bad, I wouldn't have that kind of feedback. And at least to this point, I think it not only isn't bad, it's preferable to do it this way. Yeah, it's a little more of a pain, but I'm more about the beer than I am the supposed pain.

YMMV.
 

Dgallo

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If you are worried about oxygen in your finished beer then pitching the whole starter is not ideal.
This introduction of oxygen through pitching in the whole starter into a fermenter and racking your wort ontop of it or pitching after racking the wort will have no ill effects on your beer, it will only have benefits. The yeast will consume all of this oxygen during fermentation, just as it does oxygen from the stir plate as it will continue multiply. The yeast need some level of oxygen during fermentation.
I'll freeze this if there is enough (most of the time) or use it to propagate more.
Freezing liquid yeast is a no go. The yeast will be fully hydrated so when you freeze it you will cause those yeast cells to burst, plummeting the viability of the yeast. You can regrow what is remaining, sure, but since you can not properly calculate the remaining viability, you are most likely terribly underpiching. This causes all sorts of problems such as infections that won’t be out competed, negative byproducts, and low attenuation with the potential for stuck fermentations
 

BitterSweetBrews

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We're going to have to disagree on this; I'm not pitching into the finished beer, I'm pitching into the just-created wort. Any oxygen in the starter is simply going to be used by the yeast as it multiplies in the fermenter, no differently than the oxygen that I'm putting into the wort using an oxygen tank and an aeration stone on a wand.



A lot of people argue this, and I don't know why. That wort in the starter begins almost devoid of oxygen; it's been boiled off, which is something the LODO people do to deoxygenate strike water prior to doughing in.

******

Can you produce beer without oxygenating the starter? Sure. I used to do exactly that, before I began to look into the LODO stuff. I began to wonder why I would want to pitch yeast into a starter wort that was devoid of oxygen.

I couldn't think of a reason why that made sense, as the yeast have to wait until the stir plate brings in oxygen, though how quickly that happens isn't clear.



Again, we have to disagree here. A stir plate might or might not be the best way to introduce oxygen; I'm not sure why anyone would oppose the idea of adding oxygen directly so as to get the yeast going as quickly as possible.

***********

As to the starter wort tasting badly, well, that's true; however, it's not carbonated, not conditioned, the yeast hasn't had any time to clean up after itself, and most interesting of all, when people add DME into a wort, they're setting up exactly the same thing, i.e., yeast will convert DME to alcohol. What's different? Nothing I can see.

Now, it's possible there's something here I'm not seeing, as I don't know everything there is to know about brewing, but I cannot see where this is a bad idea, and I can see a lot of reasons why it's a good idea.

***********

I've noted above in this thread the advantage to a fast takeoff of yeast: it has the best chance of outcompeting any nasties that get into the wort.

The same could be said for starters.

Now, if you don't want to believe any of this, that's fine. You can do what you want, and it won't have any effect on my beer. And I'll do what I want, and do that knowing that I've had friends who want to buy my beer, produced with my starter protocol, at commercial prices, and a local person who wants me to brew so she can sell my beer in her bar.

I am thinking that if what I do is so bad, I wouldn't have that kind of feedback. And at least to this point, I think it not only isn't bad, it's preferable to do it this way. Yeah, it's a little more of a pain, but I'm more about the beer than I am the supposed pain.

YMMV.
It is lucky you live in a place where you can make and sell your beer without having a brewery license. I have also had people want to purchase my beer, but can't/won't sell it because of stupid laws and a government that wants to collect taxes.

My preference is not to add what I consider oxidized, bad tasting, un-hopped beer to my wort. I would just never add a half gallon (2 liters) of crap beer to a great 5 gallon recipe. I would rather decant and pitch a minimal amount of this liquid. Either way works.

There is no doubt that oxygenating wort, even starter wort can help. But. I never really thought about doing it. I just consider it unnecessary in a starter on a stir plate that has a stir bar just for this purpose. I am sure it probably does give it a jump start of a few minutes. But, I would bet the stir plate introduces just as much O2 in 30 minutes as you do with a 20-30 second burst. It does take a while. Do what ever works for you and makes you feel comfortable. That's the beauty of this "hobby".

I do push pure O2 to oxygenate the wort in my fermenter at the beginning of fermentation and would not have it any other way. I use to use an aquarium pump and aeration stone for 20-30 minutes before I got my oxygenator. There have been studies that show you can't get the oxygen level in the wort nearly as high with an aerator as you can with pure Oxygen. It is really the way to go..
 

BitterSweetBrews

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This introduction of oxygen through pitching in the whole starter into a fermenter and racking your wort ontop of it or pitching after racking the wort will have no ill effects on your beer, it will only have benefits. The yeast will consume all of this oxygen during fermentation, just as it does oxygen from the stir plate as it will continue multiply. The yeast need some level of oxygen during fermentation.
My preference is not to add what I consider oxidized, bad tasting, un-hopped beer to my wort. I would just never add a half gallon (2 liters) of crap beer to a great 5 gallon lager recipe. I would rather decant and pitch a minimal amount of this liquid. Either way works.

Freezing liquid yeast is a no go. The yeast will be fully hydrated so when you freeze it you will cause those yeast cells to burst, plummeting the viability of the yeast. You can regrow what is remaining, sure, but since you can not properly calculate the remaining viability, you are most likely terribly underpiching. This causes all sorts of problems such as infections that won’t be out competed, negative byproducts, and low attenuation with the potential for stuck fermentations
That is not true if you follow the proper procedures for freezing the yeast and building up your starters later. It is no different than if you propagated yeast from a bottle conditioned beer or a slant.

Following is an excellent article about all things yeast:

https://www.maltosefalcons.com/tech/yeast-propagation-and-maintenance-principles-and-practices


If you just throw some washed yeast in a container and freeze it you are correct, most of the cells will have burst. If you follow the proper procedures and buffer the yeast solution with glycerin it will cushion the cells and keep them from bursting.

Here is a homebrewtalk thread about yeast freezing:

https://www.homebrewtalk.com/freezing-yeast.html


Here is also a video I did on freezing yeast. It is simple and it lasts for years. In fact I just pitched, an hour ago, the dregs from a decanted 2 liter starter I built up in three steps from some yeast I froze 15 months ago. I have done this many times and never had any problems. Feel free to watch it and subscribe to my channel.

 
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mongoose33

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It is lucky you live in a place where you can make and sell your beer without having a brewery license. I have also had people want to purchase my beer, but can't/won't sell it because of stupid laws and a government that wants to collect taxes.
I never said I was selling it. I said they wanted to buy it and in the case of the bar owner, sell it. Whether I ever get a license to do so is another question but irrelevant to the issue at hand, which is if I was having so much trouble from pitching an entire starter.....would I have people wanting to buy and sell my beer? Seems....unlikely.

My preference is not to add what I consider oxidized, bad tasting, un-hopped beer to my wort. I would just never add a half gallon (2 liters) of crap beer to a great 5 gallon recipe. I would rather decant and pitch a minimal amount of this liquid. Either way works.
I've only ever once done a half-gallon starter. Even with lager recipes I only do a liter starter, pitch warm, wait 6 hours at that temp, then begin to drop to fermentation temp. Despite that also being outside the norm, it works.

There is no doubt that oxygenating wort, even starter wort can help. But. I never really thought about doing it. I just consider it unnecessary in a starter on a stir plate that has a stir bar just for this purpose. I am sure it probably does give it a jump start of a few minutes. But, I would bet the stir plate introduces just as much O2 in 30 minutes as you do with a 20-30 second burst. It does take a while. Do what ever works for you and makes you feel comfortable. That's the beauty of this "hobby".
I doubt that very much. You cannot create as much oxygenation with simple aeration as you can with an oxygen wand pumping oxygen (as you note below). Hard to believe a stir plate would exceed shaking or other methods of aerating (not oxygenating) to say nothing of actually oxygenating.

I do push pure O2 to oxygenate the wort in my fermenter at the beginning of fermentation and would not have it any other way. I use to use an aquarium pump and aeration stone for 20-30 minutes before I got my oxygenator. There have been studies that show you can't get the oxygen level in the wort nearly as high with an aerator as you can with pure Oxygen. It is really the way to go..
This is why I think oxygenating the starter wort is superior. Nobody has to do it. I have my reasons for doing it, they're very well supported, and the evidence is that it works. YMMV, and to each his own.
 

Dland

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What I do: Keg it and crash it right out of fermentor, supply kegs w 5# CO2 to be sure lid has sealed, start forced carb after keg is cooled and crashed.

Or more likely lately; keg it and spund it up to desired CO2 volume (and do D rest if lager). Ramp temp down to ambient cellar temp and crash (33Fworks well for me).

For what I brew, the difference between pretty good to darn good is all in letting it cold lager for a while, lagers especially, but ales as well.
 

Dgallo

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My preference is not to add what I consider oxidized, bad tasting, un-hopped beer to my wort. I would just never add a half gallon (2 liters) of crap beer to a great 5 gallon lager recipe. I would rather decant and pitch a minimal amount of this liquid. Either way works.



That is not true if you follow the proper procedures for freezing and building up your starters. It is no different that if you propagated yeast from a bottle conditioned beer or a slant.

Following is an excellent article about all things yeast:

https://www.maltosefalcons.com/tech/yeast-propagation-and-maintenance-principles-and-practices


If you just throw some washed yeast in a container and freeze
My preference is not to add what I consider oxidized, bad tasting, un-hopped beer to my wort. I would just never add a half gallon (2 liters) of crap beer to a great 5 gallon lager recipe. I would rather decant and pitch a minimal amount of this liquid. Either way works.



That is not true if you follow the proper procedures for freezing the yeast and building up your starters later. It is no different than if you propagated yeast from a bottle conditioned beer or a slant.

Following is an excellent article about all things yeast:

https://www.maltosefalcons.com/tech/yeast-propagation-and-maintenance-principles-and-practices


If you just throw some washed yeast in a container and freeze it you are correct, most of the cells will have burst. If you follow the proper procedures and buffer the yeast solution with glycerin it will cushion the cells and keep them from bursting.

Here is a homebrewtalk thread about yeast freezing:

https://www.homebrewtalk.com/freezing-yeast.html


Here is also a video I did on freezing yeast. It is simple and it lasts for years. In fact I just pitched, an hour ago, the dregs from a decanted 2 liter starter I built up in three steps from some yeast I froze 15 months ago. I have done this many times and never had any problems. Feel free to watch it and subscribe to my channel.

its all good man. To each their own. I do a much smaller starter than you, .5-1l because pitching the active starter will have zero lag time and multiply the yeast within the proper pitch rates within the first 8 hours. I’ve never heard of a proper way of freezing yeast but seems like it works with the glycerin but it just quite the added step and time. why not just over build a starter since you decant anyway? Then you can save the yeast for later in sterilized mason jars if you brew often enough.
 
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BitterSweetBrews

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its all good man. To each their own. I do a much smaller starter than you, .5-1l because pitching the active starter will have zero lag time and multiply the yeast within the proper pitch rates within the first 8 hours. I’ve never heard of a proper way of freezing yeast but seems like it works with the glycerin but it just quite the added step and time. why not just over build a starter since you decant anyway? Then you can save the yeast for later in sterilized mason jars if you brew often enough.
Agreed. I do keep a yeast bank of both frozen and unfrozen yeast. The frozen yeast is pretty much strains I don't use often enough to be viable in the fridge. I brew maybe 10-12 batches a year, so unless I do the same style over and over the yeast needs to be in long term storage or I have to spend another $8 for more. While I can easily afford to buy it fresh, if I don't need to I don't. I look at it as just another technique to be learned to increase my knowledge of brewing.

When I wash yeast, in addition to keeping it in the fridge, I try to also freeze some of it at the same time to build up my assortment bank and for times when the refridgerated yeast is older. Freezing works for that and for times when I haven't planned ahead and am brewing out of stuff on hand. With that being said, for standard styles I find I have been buying more dry yeast lately because it is easy and good. So, this also increases the turn around time of the stored specialty stuff. I always have a few dry packs on hand for impromptu brew days and in case I have a stalled fermentation. I live within 15 minutes of 3 different LHBSs, so if all else fails, I can always pick up yeast on the fly.
 

LittleRiver

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I want to do a cold crash in my primary fermentation bucket. I'm expecting that as it cools it will suck in oxygen (through the airlock). Is there a good way to prevent this? I would put it in a keg but I don't have an extra one.
Here's how I do it. I found the little nylon tube fittings at Ace Hardware, and the mylar balloon at Walmart. A nurse friend found the tube clamp for me.

For the first two days of fermentation the tube clamp is closed, so the balloon does not fill with air that is pushed out of the headspace by fermentation.
IMG_20190114_195318_711.jpg


On the third day I open the clamp and Spiderman fills up with C02.
IMG_20190113_140047_768.jpg


This is cold crashed to 38F.
IMG_20190216_082352_546.jpg


I clean a keg, fill it completely with StarSan, and use bottled CO2 to push out the StarSan -- leaving a CO2 filled keg. I bleed almost all of the pressure off the keg, to the point where I feel one more tug on the pressure relief would fully depressurize it.

I connect the keg beer connector to the fermenter drain valve, and connect the keg gas connector to the top of the fermenter. I close the tube clamp to the balloon, because there's no point in letting it fill up again -- I roll it up for storage between brews.
IMG_20190216_083644_263.jpg
 

Wagon_6

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That’s pretty cool. How many star san kegs do you think you can empty with a 5 lb tank?
 

LittleRiver

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... How many star san kegs do you think you can empty with a 5 lb tank?
I have a chart that says a 5lb tank will dispense 15-22 5gal kegs. A 10lb tank will do 31-44. A 20lb tank will do 62-87.

I'm starting out with just two taps, two 5gal kegs, and a 5lb C02 tank inside. I've build the keezer so it'll be an easy upgrade to add two more taps, two 3gal kegs, and an exterior 20lb tank. When I do that I'll keep the 5lb tank as a spare.
 
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