to add air to fermenting or not to add air..

[zember311]

I saw ( how it's made ) the other week and they were showing you how winery's make their wine. One thing they said was winery's will drain their red wines and screen it once during the primary fermentation. They said they did this to remove some debris and to also add air to the wine during fermentation.


Then I have seen a few people online using air pumps and air stones, and just the other day I found the inventer of the X-71 ? batches to also add air to the primary fermentation.


What would the pros be of this ? other then something to do with idle hand syndrome, is there any proven benifits to aiding so much to these little critters called yeast ?

 

[acesover]

I THINK ITS MORE ABOUT LETTING SOME OF THE GASSES OUT NOT SO MUCH A BOUT PUTTING AIR IN.

 

[scubaman2151]

From my limited understanding it is ok to let air get to the wine duing primary fermentation becuase it is good for the yeast. I know for sure it wont hurt it during primary but i would think there isnt a reason to go out of your way to add air to your wine.


ScubaEdited by: Scubaman2151

 

[joeswine]

Scubaman2151 there are some great sorces out there ,such as jack keller.com try it although here you can actually write to someone and get a response from many of us there are other sorces in case you get stuck,I think the forum is a better path to take but if in a pinch,,,,,,do what you need to do,,,,,to correct or reference a problem,,,air in the fermentation process will not hinder the wines progress,in a lot of cases taking off the top of a bucket lid and placing cloth accoss it is all thats needed,after fermentation is completed and at the first raking air is your enemy,air lock goes on settling takes place along with degassing,but no air intrusion,air will make the wine oxidize and get funky then go bad,thats why K/MET and sorbate are added ,but no air

patient as always is required

 

[smokegrub]

I stir my primary several times during the first 2-3 days.

 

[scotty]

Stirring is probably all we need with the size of the batches we make.
In a 9000 gallon drum i would guess aeration is necessary.




I guess

 

[harryhebert]

I work only with 1 gallon jugs and Welch's concentrated grape juice. To insure that there is ample air during primary fermentation I put a round coffee filter secured with a rubber band over the mouth of the jug. This way if there proves to be a volcano of foam, I can always change the 'diaper'. I go for high % of alcohol so on the initial fermentation I add 2 1/4 cups of sugar. I leave it be and watch it and usually 3 days its calmed down enough for me to chapatalize when I add 1 more cup of sugar. I find that adding the sugar to lukewarm water that I use for the initial mixup really produces a most active initial fermentation. After adding the second batch of sugar, I put on a cap and shake the jug vigorously. Then it takes about 5 or 6 days before the protection of CO2 evidenced by the foam is low enough to airlock. I make a yeast starter with the champagne yeast, 2 tsp. sugar, and 2 oz. grape or apple juice which works well after sitting for a day before using. According to my vinometer, I am making 23% alcohol wine.

 

[PeterZ]

Yeast need small amounts of oxygen to reproduce, but the conversion of sugar to alcohol does not require any. Once you have an active fermentation going, no further aeration is necessary.

 

[masta]

Adding air to the must is important to the yeast but how much and how it is accomplished varies as you have noted. Personally I aerate my must and wort (when making beer) with nothing more than a drill mounted Fizz-X. The large scale winery introducing air during the fermentation could be due the shear volume of must and yeast to guarantee the cells have plenty of oxygen for budding.


This info below taken from a yeast producer should help you understand why oxygen is important.



<DIV style="MARGIN: 0in 0in 0pt">"Oxygen is a necessary nutrient for proper yeast growth.Yeast requires oxygen for the synthesis of sterols.Sterols are membrane lipids which help maintain cellular fluidity and permeability enabling cells to grow and bud.Every time a cell buds the cellular sterol content is diluted.Once the level becomes too low (in approximately 3-4 doublings) the cells lose the ability to bud.Sterol content generally is the limiting factor of yeast growth.Synthesis of sterols occurs only when oxygen is present. Thus, it is critical to supply the yeast with appropriate levels of oxygen.
<DIV style="MARGIN: 0in 0in 0pt">
<DIV style="MARGIN: 0in 0in 0pt">Yeast require 8 to 16 ppm of oxygen.Oxygen is typically dissolved into the must during crushing/destemming and then during pump-over/punching down for red wines fermented on skins.The most that atmospheric oxygen can provide to must is about 8 ppm.For this reason, it may be necessary to rack the wine or pump-over shortly after inoculation.
<DIV style="MARGIN: 0in 0in 0pt">
<DIV style="MARGIN: 0in 0in 0pt">Pure oxygen can also be used to provide adequate oxygen in the must.Oxygen can be injected using a scintered stone.It is important to note that too much oxygen can be added using pure oxygen.Up to 40 ppm can be achieved with pure oxygen, but it is best to keep the dissolved oxygen levels below 20 ppm.
<DIV style="MARGIN: 0in 0in 0pt">
<DIV style="MARGIN: 0in 0in 0pt">High sugar levels and high must temperatures both make it more difficult to dissolve oxygen into must.For high sugar musts or musts that have high temperatures, additional oxygenation/aeration may be necessary."
<DIV style="MARGIN: 0in 0in 0pt">
<DIV style="MARGIN: 0in 0in 0pt">

 

[zember311]

Great info guy,


Coming from the hydroponic background, it was basic knowledge to know that Water only holds ( X ) amount of oxygen, once that would be depleted, there would be no more until it was introduced back into the water .


Different air filters of different defussing grades from micron sizes and such were all the hype, but the basic truth to aeroating water is always the same, it is the exchange at the water;s surface where oxygen is intreoduced to the water, ( bubbles breaking ont he surface ) as with a open fermenting tank it makes sense that there would be an oxygen exchange since the co2 bubbles are constantly breaking the surface.


But in using gallon jugs as I do for primary and secondary fermentation, I always us an air lock, so there is no exchange of oxygen when the co2 breaks the water surface, making my oxygen levels in the glass jugs a lot lower during the primary fermentation then those that would use a plastic jug and just a loose cover or such that would still allow amounts of oxygen to enter the area,. ( we could get picky and talk about the co2 blanket since co2 is heavier then oxygen, but lets not


where as someone that uses a bucket and stirs it once a day or so, is still giving more oxygen to the live yeast then a gallon jug with lock 24/7.


I wouldn't say that this ( thought ) was a concern of ( fermenting speed ) as apposed to catering to the little critters of yeast.


My interest started as information above shows answers.


I have 3 different containers, a 3 gallon, 1 gallon and 500 ml jug, the 3 gallon is steady in bubbling over the past 7 days as apposed to the 1 gallon jug, though they were all the same sugar level and same yeast amounts and grapes, the 1 gallon slowls in fermenting alot quicker then the 3 gallon.


then on the other hand, I have the 500 ml jug fermenting at first with the same sugar level as the others, it slowed but did not stop, faster then the 1 gallon, so I noticed a trend, EVEN though the sugar levels measured about the same at the time of slowing, the fermemting times how ever changed.


then when I went way over kill on the sugar levels in the 500 ml 1.20 the fermetation seemed to slow very quickly, yet all values still remained the same,


So that was a good finding, I want to start another 2 batchs of equal everything, but stir one and not the other to see how it effects the yeast activvty and such,



Edited by: zember311

 

[grapeman]

Healthy and happy little critters makes for a more tasty wine. In the absence of adequate oxygen, undesireable flavors and biproducts may occur in greater numbers.

 

[zember311]

Healthy and happy little critters makes for a more tasty wine. In the absence of adequate oxygen, undesireable flavors and biproducts may occur in greater numbers.

BINGO !


that makes sense ,,,


Thanks !

 

[zember311]

Adding air to the must is important to the yeast but how much and how it is accomplished varies as you have noted. Personally I aerate my must and wort (when making beer) with nothing more than a drill mounted Fizz-X. The large scale winery introducing air during the fermentation could be due the shear volume of must and yeast to guarantee the cells have plenty of oxygen for budding.


This info below taken from a yeast producer should help you understand why oxygen is important.



<DIV style="MARGIN: 0in 0in 0pt">"Oxygen is a necessary nutrient for proper yeast growth.Yeast requires oxygen for the synthesis of sterols.Sterols are membrane lipids which help maintain cellular fluidity and permeability enabling cells to grow and bud.Every time a cell buds the cellular sterol content is diluted.Once the level becomes too low (in approximately 3-4 doublings) the cells lose the ability to bud.Sterol content generally is the limiting factor of yeast growth.Synthesis of sterols occurs only when oxygen is present. Thus, it is critical to supply the yeast with appropriate levels of oxygen.
<DIV style="MARGIN: 0in 0in 0pt">
<DIV style="MARGIN: 0in 0in 0pt">Yeast require 8 to 16 ppm of oxygen.Oxygen is typically dissolved into the must during crushing/destemming and then during pump-over/punching down for red wines fermented on skins.The most that atmospheric oxygen can provide to must is about 8 ppm.For this reason, it may be necessary to rack the wine or pump-over shortly after inoculation.
<DIV style="MARGIN: 0in 0in 0pt">
<DIV style="MARGIN: 0in 0in 0pt">Pure oxygen can also be used to provide adequate oxygen in the must.Oxygen can be injected using a scintered stone.It is important to note that too much oxygen can be added using pure oxygen.Up to 40 ppm can be achieved with pure oxygen, but it is best to keep the dissolved oxygen levels below 20 ppm.
<DIV style="MARGIN: 0in 0in 0pt">
<DIV style="MARGIN: 0in 0in 0pt">High sugar levels and high must temperatures both make it more difficult to dissolve oxygen into must.For high sugar musts or musts that have high temperatures, additional oxygenation/aeration may be necessary."
<DIV style="MARGIN: 0in 0in 0pt">
<DIV style="MARGIN: 0in 0in 0pt">~~~~~~~~~ great read thanks ! ~~~~~~~~~~~

<DIV style="MARGIN: 0in 0in 0pt">
<DIV style="MARGIN: 0in 0in 0pt">

 

[PeterZ]

Just keep in mind that oxygen is an oxidizer and can cause browning of the juice/must. Once the fermentation gets going the CO2 bubble production will drive off the other gasses, just like sparging with nitrogen will drive off other gasses.

 

[zember311]

So I have been messing around with different batches, trying to entertain my brain and see if there really is a difference, and WOW; I stumbled across a few issuses that I wanted to share with you all and see if you could offer some of your learnings as well.


1rst off, I have a 3 gallon batch of wine that is STILL fermenting. I started this batch on the 13th of Jan at 1.090 and as of today it is only at 1.030. fermentation isnt stuck, it is still going by slugish. But I found some cool things out along the way.


a) I started this batch in a 3 gallon secondary with airlock. I have been told that during the first 24 to 72 hours of incubating yeast, they need oxygen to multiply and if there is enough oxygen during this time, the amount of live yeast will have significant number differences then those batches that did not get theright amount of oxygen.


b) The second mistake I made but was a good learning curve was in the beginning of this batch I did not have a hydrometer, so things were a bit out of the norm in the ways I delt with this wine. I Racked it twice, thinking well, if I rack it by seperating the lees during fermentation, that when it was finished with fermentation, the wait time till it cleared would be greatly reduced. BUT I just recently found out that live yeast can settle in the lee and by seperating the lee from the wine before primary fermentation was even completed, I was removing all the live goodies I should have just left in there.


So all in all that was my mistake.


So I moved to a 7 gallon white bucket, started the batch at the same exact SG. but this time I did a few things different.


a) during the first 2 days I placed the lock on the bucket but did not add any water to the lock.


b) every two days after that, using the bottle spicot, I drew 3 gallons out of the fermentor and poured it back in to the top, aerating the wine by the splashing of the wine into the 1 gallon jar and the splashing of the wine back into the bucket. and only filled the lock with water on the 3rd day.


This wine was started on the 29th of january and as of today, the SG level is at 1.030.


Then I have a 750 Ml bottle, I started at 1.090 air lock instantly, I have not touched it since I started it on the 17th of Jan, I just checked the Sg it is only at 1.050 as of today,but if has been bubbling ever since.when I made the batch I ran the juice as high up as I could in the neck without touching the lock and leaving a bit of room for the bubbling , I then added the yeast and put the lock on.




So just to entertain my brain.


I have 2 one gallon jugs I started last night.


1) with an air lock
1) with no airlock but a coffee filter rubber banded to the top.


The one with the airlock I will do nothing to. not touch, not stir. nothing.


the one without a airlock, once a day I will pour the entire contents into a clean gallon jug, only to further aerate it. then after the 3rd day I will replace the airlock to see if there is a difference.

 

[Wade E]

In my opinion you are going through great lengths to do just what you can do with a drill mounted stirrer and reduce the risk of adding bacteria to your wine. Its a lot easier to just stick the stirrer in a and pull the trigger and then spray it down or soak it with k-meta suction but to each their own. It does help to get the extra air to it but a side by side comparison really wont tell you much unless you do a big batch, stir it up like crazy to make sure everything is dispersed equally and then split int 2 parts.

 

[zember311]

In my opinion you are going through great lengths to do just what you can do with a drill mounted stirrer and reduce the risk of adding bacteria to your wine. Its a lot easier to just stick the stirrer in a and pull the trigger and then spray it down or soak it with k-meta suction but to each their own. It does help to get the extra air to it but a side by side comparison really wont tell you much unless you do a big batch, stir it up like crazy to make sure everything is dispersed equally and then split int 2 parts.

Without a doubt I am a big germ phobic person when it comes to food, so I make sure to pay attention to what people tell me and use common sense with my wines since it is after alla food.. I just like to tinker

See when I was a kid at the beach while all the cool kids had those sand castle molds and cool plastic shovels, I have to uns an old beer cup as a shovel and a old cut in half gallon jusg as a mold .

somethings never change.