Mold on cloth above fermenter!

[MSIMSON]

Background: I am making a 5 gallon batch. Using a fermenting bucket.
I used about 7 pounds of sugar plus about 5 pints of grape concentrate plus 20lbs of blueberries. And yes, I used wine yeast.

So here is an update: Yesterday, I cracked the lid of the fermenting bucket and placed paper towels over the opening to prevent bugs from entering. I also placed a folded paper towel over the opening where the airlock goes.

This morning when I checked it, the paper towels over the opening were soaked with the must (it foamed up high enough to make contact) and the paper towel over the airlock had mold around its corners and edges also, there were fruit flies around the bucket but I don't think they could have gotten into the must.

I have since removed the fermenter lid, thoroughly sterilized it, and tightly sealed it over the must (no oxygen intake now) I also sterilized the airlock and filled it sterilized water. The airlock is bubbling alot now so I know the yeast is doing is thing but I'm very worried about that mold I found. What does it mean? What should I expect? Is my wine gonna turn to vinegar?

 

[jamesngalveston]

i am sorry to tell you....remove the lid , cover the top with a pillow case secured with a rubber ban, elastic, belt, what ever you have..
yeast needs as much oxygen as you can give it for the primary fermentation.
when it gets to .990 are the same sg for 3 days, move to secondary, then use your airlock....

 

[MSIMSON]

I though the process of converting sugar to CO2 and ethanol was anaerobic meaning it does not require oxygen?

 

[jamesngalveston]

* The Primary Fermentation will typically last for the first three to five days. On average, 70 percent of the fermentation activity will occur during these first few days. And in most cases, you will notice considerable foaming during this time of rapid fermentation.

The primary fermentation is also called an aerobic fermentation because the fermentation vessel is allowed to be opened to the air. This air plays an important roll in the multiplication of the yeast cells.

Here's how important. The little packets of yeast that is generally called for in a five gallon wine recipe will typically be multiplied up to 100 to 200 times during the few days of primary/aerobic fermentation. Without air this multiplying stage is hindered. That is why it is important that you do not use an air-lock during the first few days of a fermentation and allow the fermentation to be open to air.

Alcohol is being produced during the primary fermentation as well, but a significant portion of the yeast's energy is being devoted to reproducing itself.

 

[robie]

That small amount of mold is not a problem. Later, when fermentation is completed, you will add a stabilizer - k-meta. Its sulfite will kill anything that might harm your wine and provide protection for a few more months.

Same for fruit flies. You just have to do your best to keep them out, but don't panic if you find one or two floating in your wine.

Make sure that as you are making wine, you always use a good sanitizer to clean your equipment and anything that will touch your wine.

Lots of folks do seal up their wine with an air lock during primary fermentation. This, however, is not always a good idea and is not considered "best practice", even though many wine makers have done this successfully for years.

When you first pitch your yeast, that single packet represents only a tiny fraction of the number of yeast you should have in order to get a good fermentation. So, they have to really, really multiply.

During the first 1/3 or so of fermentation the yeast do need oxygen in order to multiply. It is hard to say how many days 1/3 equates to being, as each fermentation can take different amounts of time to run its course. I, personally, think of that 1/3 ending about when the SG reaches 1.040.

Primary alcohol fermentation is considered to be until the specific gravity (SG) of the wine gets down to about 1.010. At that point, you begin what most home wine makers refer to as "secondary alcohol fermentation" or sometimes just "secondary".

During primary alcohol fermentation, the very active yeast in the wine are producing so much CO2 gas that it is preventing excess oxygen from entering the wine. CO2 is being expelled from the wine at a tremendous rate. It is OK during this phase to allow oxygen into the fermenter as long as the fermenter has a covering to prevent critters from getting into it. That's why we say to loosely cover the wine. It is even a good thing to stir the wine daily for the first 3 or 4 days. This makes sure the yeast have the oxygen they need in order to build up to a good colony.

As primary starts winding down and the yeast activity lessens, less CO2 is being produced, so when you see the bubbling of the air lock slow or the SG gets to about 1.040, it doesn't hurt a thing to go ahead and seal up the wine. This is especially true for whtes wines, which tend to be more susceptible to oxidation. Me? I ferment in a plastic fermenter bucket, so I continue to keep the lid setting loosely on the bucket with a towel over the air lock hole, but you can seal it at that point if you so desire.

Now, once the SG reaches 1.010, regardless of what you heard, the fermentation has slowed enough that not enough CO2 is being produced to protect the wine adequately. At this point, the wine should be sealed up and an air lock installed. It doesn't hurt to open the container every 2 or 3 days to check the specific gravity. At 1.010, most people will rack the wine to a carboy and add an air lock. Others will simple seal the fermenter bucket lid and add an air lock. Best option is to do whatever your instructions say to do.

The wine does not need stirred after the wine is in secondary alcohol fermentation. During this secondary, the wine does not need to be topped off.

Starting at an SG of 1.010, the wine will need to be protected from air until it enters your wine glass.

Once the SG has reach 1.000 or lower and the reading has stopped changing for 3 days in a row, alcohol fermentation is finished.

Now that fermentation is done, rack the wine again and top off the container off and keep it topped off.

Don't ever leave your wine exposed to air after the SG reaches 1.010.

 

[cedarswamp]

CO2 being heavier than air has me questioning the validity of yeasts needs of oxygen from an outside source.

 

[KenS]

CO2 being heavier than air has me questioning the validity of yeasts needs of oxygen from an outside source.

Lots of threads that discuss this, and opinions vary. I have only made kit wines, and their instructions always say "if your primary fermenter uses an airlock, insert it now", right after pitching the yeast.

I always do that, but I then open the fermenter daily (at least) to give a gentle stir, so maybe that's enough oxygen. I have never had a stuck fermentation, nor have any of my kits failed to ferment to dry in the time expected. Again, just my own experience.

 

[robie]

CO2 being heavier than air has me questioning the validity of yeasts needs of oxygen from an outside source.

This subject has been a sore source of contention for a long time on this forum. I don't plan on getting into another [p---] contest over it. However, I will present what I believe to be true and let it go.

Just before and even during the first part of consuming sugars, yeast need oxygen to multiply to a huge colony many, many times greater that what is provided in a pitched packet of yeast. Without oxygen, yeast won't ever get to an scientifically stated adequate colony size. Some CO2 already are being produced of course during this time because the yeast already present start converting sugar (eating) very quickly. This is regardless of the fact that CO2 is heavier than oxygen.

Yeast don't need oxygen just to convert the sugars.

Speaking of what I assume you mean by "an outside source"
Just before pitching the yeast, if one could actually remove all the oxygen out of the must and keep it from ever acquiring any (good luck!), the yeast number would not grow much at all. But of course the must is always going to have oxygen in it, regardless. Even a standing must, which has not been stirred lately is going to have some oxygen in it.

Some feel erroneously that from the get-go, the must natually will contain enough oxygen for the yeast. If one looks at the formula for the amount of yeast in such a resting liquid, compared to what the actually yeast need, there is a shortage of oxygen. Each yeast strain can have a different level of need, of course.

Just because some, even commercial wine makers seal up a wine (like a Chardonnay) from the very get-go and keep all air away from it all during fermentation, doesn't disprove the fact that there is an aerobic phase and an anaerobic phase for the yeast to complete a healthy fermentation.

It's Friday; I won't be back on until Monday, so all you guys/gals can argue this point as much as you like, but it still doesn't change the fact that both aerobic and anaerobic phases are fact.

Have fun!!!

 

[robie]

Lots of threads that discuss this, and opinions vary. I have only made kit wines, and their instructions always say "if your primary fermenter uses an airlock, insert it now", right after pitching the yeast.

I always do that, but I then open the fermenter daily (at least) to give a gentle stir, so maybe that's enough oxygen. I have never had a stuck fermentation, nor have any of my kits failed to ferment to dry in the time expected. Again, just my own experience.

Your gentle stirring is going to add needed oxygen to the must, even though there is a nice layer of CO2 at the top of the fermenter bucket. That is a good habit to have. Do it twice a day for the first several days of primary. It generally is more important for a red than for a white.

Some (not all) kit makers have you seal up the wine mainly for their good not your wine's. They are more afraid of oxidation than they are interested in your having the best and most complete fermentation possible. Remember, they have to guaranty the kit to come out or your money back. "Come out" is a very subjective term. They know there is going to be enough oxygen already in the recently blended juice and water to "get by". If you keep it completely sealed up and only open to check SG a few times, they know the wine will not get oxidized. Works but not really "best practice".

 

[jamesngalveston]

well, add some yeast to sugar water, and close it up tight, what happens.
nothing

 

[cedarswamp]

Just my humble opinion gentlemen.

 

[loumik]

MSIMSON,
I would very strongly recommend that you read and follow the advise that Robie has given you above. He has been doing this for quite some time and knows what he is talking about.

LOUMIK

 

[MSIMSON]

That small amount of mold is not a problem. Later, when fermentation is completed, you will add a stabilizer - k-meta. Its sulfite will kill anything that might harm your wine and provide protection for a few more months.

Same for fruit flies. You just have to do your best to keep them out, but don't panic if you find one or two floating in your wine.

Make sure that as you are making wine, you always use a good sanitizer to clean your equipment and anything that will touch your wine.

Lots of folks do seal up their wine with an air lock during primary fermentation. This, however, is not always a good idea and is not considered "best practice", even though many wine makers have done this successfully for years.

When you first pitch your yeast, that single packet represents only a tiny fraction of the number of yeast you should have in order to get a good fermentation. So, they have to really, really multiply.

During the first 1/3 or so of fermentation the yeast do need oxygen in order to multiply. It is hard to say how many days 1/3 equates to being, as each fermentation can take different amounts of time to run its course. I, personally, think of that 1/3 ending about when the SG reaches 1.040.

Primary alcohol fermentation is considered to be until the specific gravity (SG) of the wine gets down to about 1.010. At that point, you begin what most home wine makers refer to as "secondary alcohol fermentation" or sometimes just "secondary".

During primary alcohol fermentation, the very active yeast in the wine are producing so much CO2 gas that it is preventing excess oxygen from entering the wine. CO2 is being expelled from the wine at a tremendous rate. It is OK during this phase to allow oxygen into the fermenter as long as the fermenter has a covering to prevent critters from getting into it. That's why we say to loosely cover the wine. It is even a good thing to stir the wine daily for the first 3 or 4 days. This makes sure the yeast have the oxygen they need in order to build up to a good colony.

As primary starts winding down and the yeast activity lessens, less CO2 is being produced, so when you see the bubbling of the air lock slow or the SG gets to about 1.040, it doesn't hurt a thing to go ahead and seal up the wine. This is especially true for whtes wines, which tend to be more susceptible to oxidation. Me? I ferment in a plastic fermenter bucket, so I continue to keep the lid setting loosely on the bucket with a towel over the air lock hole, but you can seal it at that point if you so desire.

Now, once the SG reaches 1.010, regardless of what you heard, the fermentation has slowed enough that not enough CO2 is being produced to protect the wine adequately. At this point, the wine should be sealed up and an air lock installed. It doesn't hurt to open the container every 2 or 3 days to check the specific gravity. At 1.010, most people will rack the wine to a carboy and add an air lock. Others will simple seal the fermenter bucket lid and add an air lock. Best option is to do whatever your instructions say to do.

The wine does not need stirred after the wine is in secondary alcohol fermentation. During this secondary, the wine does not need to be topped off.

Starting at an SG of 1.010, the wine will need to be protected from air until it enters your wine glass.

Once the SG has reach 1.000 or lower and the reading has stopped changing for 3 days in a row, alcohol fermentation is finished.

Now that fermentation is done, rack the wine again and top off the container off and keep it topped off.

Don't ever leave your wine exposed to air after the SG reaches 1.010.

First of all, thank you so much for your incredibly detailed response.

I just have a few more questions:

1. My recipe mentioned nothing about adding a stabilizer. What is this k meta sulfite you're talking about? (I'm not using a kit, just a recipe and ingredients from my local homebrew supply store.)

2. You said (generally) fermentation is 1/3 complete when the SG reaches about 1.040. Mine started at 1.110 which is (I think) higher than normal. What would you say my SG will be about 1/3 through fermentation? (I'd guess 1.060?) I pitched the yeast on Wednesday 7/24 so I'm 3 days into fermenting though the yeast didn't begin to produce visible amounts of CO2 until Thursday night.

3. Last night, I removed the fermenter lid and airlock per your suggestion and tightly secured a pillow case (soaked, but not dripping in sterilizer) over the bucket. When I removed the lid, there was some mold on the inside of the lid! (I attached a picture of it.)



It wasn't a lot but still enough to get me worried and it was inside the fermenter this time! I know you said not to worry about a little mold but it's this amount normal?

4. Finally, you mention topping off the container when I move it to the secondary fermenter. What does this mean? Right now my wine is in a 5 gallon bucket and it is filled to about an inch from the top (above the 5 gallon mark.) The blueberries take up about 1.5-2.5 gallons and they obviously won't go onto the secondary fermenter because they won't for through the carboy opening. My carboy is (I think) 5 gallons.

Thanks so much, again!

 

[saramc]

1. K-meta is potassium metabisulphite, looks like granulated sugar. It can be used as a sanitizer if mixed at a certain strength and is also commonly used preferment, then every 90 days, and also in combination with potassium sorbate to stabilize a clear, sediment free and dry wine as you prepare to backsweeten and then bottle. If no plan to backsweeten, you stabilize with k-meta prior to bottling. K-meta it an antibacterial and antioxidant. It does not kill yeast but it will create such an unfriendly environment that wild yeast do not come out to play. You can buy potassium based Campden tablets which you pulverize and dissolve in wine or water, usually one per gallon while the granulated k-meta/KMS is typically 1/4 tsp per 5-6 gallons, check package label as manufacturers do vary, even on Campden. Most people avoid the sodium based Campden and metabisulfite that you may find on the shelf, but it contains such a minimal amount of sodium do not panic if you use it. You can always use it for sanitizing solution. To take all guesswork out of KMS additions invest in a digital pH meter and Free SO2 Test Kit.

2.,On the 1/3 decrease, if your OG, original gravity, is 1.110 then simply divide 110 by 3 and do the math. The 1/3 sugar break or depletion point is a common reference, so just know your OG and go from there.

3. On the mold on your lid...hard to tell in photo, but is it fuzzy? If you place a dripping wet cloth over opening of bucket, etc. you are asking for contamination. The outside of bucket is typically not 'clean' for long and assuming your cloth cover drapes down the outside of bucket....well, it is contaminated. But do not worry, you can fix it. That fabric needs to be dryer, do not be afraid to use clean/sanitized hands to ring out the fabric, damp is fine but drips are not good, dry is even better. Better yet, just let the clean/sanitized lid of bucket rest on the opening and place a clean, dry towel over the lid. It weighs the lid down, debris does not get in & still allows oxygen access.

4. Topping up simply means you do not leave excess headspace in your carboy. You want to ensure the liquid level is up just above the shoulder, into the neck, you do NOT want airlock to touch the liquid in carboy as this is a huge contaminant potential...your topped up carboy would appear much like a properly filled/corked wine bottle. You may have to downsize to a smaller carboy, use gallon jugs, extra wine bottles, some add clean/sanitized lead free glass marbles or stainless steel shot (3# displaces about 1 liter). Some top up with a related wine or even add fruit juice which has been sweetened to the OG so the ACV is maintained. Some add sugar-water. Some even have jugs of neutral 12% wine available, like potato wine or even a basic plain mead that they use for topping up. Each time you rack you need to top up. You can salvage as much wine as possible by pouring the sediment + remaining liquid from racking into appropriate sized jar/jug/bottle, seal with airlock & refrigerate so the lees settle to bottom and you can then decant that new layer of wine & add to your carboy. As you make a new batch, you may want to plan on an extra quart of liquid for every gallon you make, and you usually have enough liquid to ensure your batch is properly topped up.

 

[cintipam]

Robie, I also wanted to thank you for that ultra clear explanation. I am right now trying to decode instructions that differ from source to source, and you made things crystal clear for me.

I do have one question tho. When I added the sorbate and kmeta to one batch, it foamed up enough to overflow just a hair. The first batch had no reaction. Granted batch one had been stable a couple extra days, but the foamer had been at .096 for 4 days in a row. Luckily I had topped off all 3 batches at the last racking. The third batch that I started the same day is still working the ferment. That seems normal, diff stuff, diff timing, but the foaming up is not anything that i had read about.

Later tonight I plan to test taste the 2 stabilized gallons to see if I choose to add any flavorings. Hoping I interpreting the timing on that correctly.

Pam in cinti

 

[robie]

Robie, I also wanted to thank you for that ultra clear explanation. I am right now trying to decode instructions that differ from source to source, and you made things crystal clear for me.

I do have one question tho. When I added the sorbate and kmeta to one batch, it foamed up enough to overflow just a hair. The first batch had no reaction. Granted batch one had been stable a couple extra days, but the foamer had been at .096 for 4 days in a row. Luckily I had topped off all 3 batches at the last racking. The third batch that I started the same day is still working the ferment. That seems normal, diff stuff, diff timing, but the foaming up is not anything that i had read about.

Later tonight I plan to test taste the 2 stabilized gallons to see if I choose to add any flavorings. Hoping I interpreting the timing on that correctly.

Pam in cinti

I don't know how I have been missing this thread and am sorry I have not responded to your direct questions. Thanks, Sara, for helping out.

Wow, when I said a little mold on the cloth cover I had no idea about what was inside the lid. I have no idea what type of mold that might be. Maybe someone can add a comment. Some of you fruit wine makers might know what it is.

Just make sure you use the proper amount of k-meta to kill anything that might get into your wine.

What chemical are you using for sanitizing your containers and other equipment, which touches the wine?

You don't have to top off during secondary fermentation, just keep an air lock on the wine, so access to oxygen is highly limited.

That foaming is pretty typical when adding stabilizers. One never knows for sure when it will and when it won't foam over. The best approach is to assume it is going to every time. That's why you should allow several inches of head room between the top of the wine and the top of the bucket. It happens in the carboy sometimes, too. Good reason why I would set my fermenter inside a slightly larger container, like a small tub. It will catch the overflow.

 

[robie]

Just my humble opinion gentlemen.

Hi Gary,

Nothing wrong with having your own opinion. I just don't understand what you really mean, but I am interested.

I just don't understand what CO2 being heavier than oxygen has to do with the yeasts' need for oxygen (O2) during the aerobic phase? Do you not believe that there is an aerobic phase and an anaerobic phase to fermentation by yeast?

Maybe what you are saying is there is already enough O2 in the must to sustain the yeast? I think the science of it has proven this is not the case.

The CO2 being heavier than O2 is why the oxygen is lifted off the surface of the must and partially forced/pushed out of the fermenter during heavy fermentation.

 

[cintipam]

Thanks again for sharing the knowledge. I was a bit worried about the foaming. I'm not the poster with lid mold but I've been using onestep for sanitizing. For first hard cleaning I use Star san, for prestorage I use 1 tblspn of unscented bleach per gallon adding a dash of Sal Soda. That recipe I got from the winemakers Home Companion book. He also says to rinse rinse rinse with hot water afterwards. I found the sal soda leaves a film if you are not very thorough, so I have a gauge as to what is not good enuf rinse. That really helps too.

Off to test 2 cranberry batches, both at 12%. Wish me luck.

Pam in cinti

 

[robie]

Thanks again for sharing the knowledge. I was a bit worried about the foaming. I'm not the poster with lid mold but I've been using onestep for sanitizing. For first hard cleaning I use Star san, for prestorage I use 1 tblspn of unscented bleach per gallon adding a dash of Sal Soda. That recipe I got from the winemakers Home Companion book. He also says to rinse rinse rinse with hot water afterwards. I found the sal soda leaves a film if you are not very thorough, so I have a gauge as to what is not good enuf rinse. That really helps too.

Off to test 2 cranberry batches, both at 12%. Wish me luck.

Pam in cinti

If that bleach is chlorine bleach, be sure not to use it on any surface that wine directly touches, like inside carboys, fermenters, or wine bottles. It can result in cork taint, referred to as TCA.

When you sample your wine, just remember that brand new, young wine may not taste like you expect. It is still "green", so it might be a lot more tart than it will be with a little time.

Good luck!

 

[cintipam]

thanks for the warning. I should switch to the oxygen bleach. I hadn't heard of TCA before. As to my wines, the two I sampled were yummy, and I am thrilled with them. I actually prefer tart, so it's possible that later it might be not tart enuf. I'll cross that bridge if I come to it tho. These were very very tasty to me.

Pam in cinti