Making A Wine Yeast Starter To Restart A Stuck Fermentation

Posted on January 20, 2020 by AIH

There are times when no matter what you do, a fermentation will not complete the task at hand. The fermentation seemed to be going along fine. The activity was looking good. The temperature was right. Then boom! The fermentation seemingly hits a brick wall and comes to an abrupt stop.

You check the wine with a hydrometer only to discover that there is plenty more sugar that needs to be fermented. What you have here is a stuck fermentation.

In most cases you can remedy a stuck fermentation and get it started again by going over The Top 10 Reasons For Fermentation Failure, however there are times when there seems to be no solution in sight. These are the times when more drastic measures need to be taken. Namely a wine yeast starter. Keep reading to learn the basics of making a wine yeast starter to restart a stuck fermentation.

A wine yeast starter is a very dependable way to restart a stuck fermentation, particularly when you know that all the environmental conditions are correct. A wine yeast starter is different than rehydrating a yeast for a few minutes. It is actually starting a mini-fermentation for a couple of days and then adding it to the stuck fermentation.

The best wine yeast to use in a starter to restart a stuck fermentation is Champagne type yeast. This type of wine yeast is better at fermenting in diverse conditions than most others. If you do not have a Champagne type yeast on hand, you can use whatever is available and still get positive results, but always use Champagne yeast when it is available for restarting a stuck fermentation.

How To Make A Wine Yeast Starter

For restarting 5 or 6 gallons, take a quart jar and fill it half way with the wine in question. Add to that, water until the jar is 2/3 full. Put in the mix a 1/4 teaspoon of yeast nutrient, and 3 tablespoons of sugar. Be sure that the sugar becomes completely dissolve. Now you can add a whole packet of the Champagne yeast. Cover the jar with a paper towel and secure with a rubber band.

Put the starter in a cozy spot at 70° to 75°F. You should see some activity within 12 to 18 hours. You will want to pitch the wine starter into the stuck fermentation right after you see the level of foaming in the jar peak. This will usually be around 1-1/2 to 2 days. Be sure to swirl the jar to add all the sediment in the starter to the wine must, as well.

Don’t worry, you won’t end up with anything like in the picture above. That’s just there for fun, but you should see a good layer of foam be produced before it’s ready to add to the stuck fermentation.

It is a bit of work, but making a wine yeast starter to restart a stuck fermentation is the ultimate way to go when you are having a stubborn fermentation. There are more minor things you can try first, based on The Top Ten Reason For Fermentation Failure article, but when push comes to shove, making a yeast starter is the way to go.
—–
Ed Kraus is a 3rd generation home brewer/winemaker and has been an owner of E. C. Kraus since 1999. He has been helping individuals make better wine and beer for over 25 years.

Bulk Storing Wine In A Carboy

Posted on January 17, 2020 by AIH

I have 5 gallons of wine that has just cleared up. Do I have to bottle it now or can I store it in the carboy? How long will the wine last in a carboy? Or will it spoil?

Name: Gary
State: GA
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Hello Gary,

Thanks for the great question on storing wine in a carboy. It brings up some interesting points, so I’m more than glad to answer it.

Carboys are great for long-term storage. They are easy to sanitize before using. They are also clear, so you can keep a good visual on the wine while aging. The shape of the carboy has it’s advantages for bulk storing, too. More on that in a moment.

A carboy can keep and age a wine just as well as a wine bottle. Some even say that wine will age better in bulk, but I have not seen any solid evidence on this one way or the other on that matter. My guess is it depends some on the wine being bulk aged.

What I can tell you is that wine can last in a carboy just as long as in a wine bottle – years! In fact, you can think of a carboy as one big wine bottle. Looking at a carboy in this way will bring some things to light. Here are some best practices when bulk storing a wine in a carboy:

The wine must have completed its fermentation and had plenty of time to clear. It is best to verify this with a hydrometer before moving forward. You want the wine to a point to where it could be bottled if you wanted to. Storing a wine in a carboy before all the sediment has dropped out will only lead to a wine that is being aged on its sediment. This can lead to strange off-flavors.

The wine should be treated with sulfites directly after racking it into the carboy. This could either be a dose of Campden tablets, potassium metabisulfite or sodium metabisulfite. So in this respect storing wine in a carboy is no different than if you were bottling the wine in wine bottles.

There should be limited head-space in the carboy. Again, this is no different than when bottling a wine. This brings us back to the shape of the carboy. Because it has a small neck, you can keep the amount of head-space to a minimum by keeping the carboy full. You don’t have to have the wine touching the brim or anything like that, but you do want the wine up into the neck.

When using a carboy for long-term storage you do not want to use an air-lock on it. Air-locks can dry out, among other issues. You will want to use either a tapered cork or a solid rubber stopper. The goal is to keep the carboy sealed-up tight… again, like a wine bottle aging.

This bring me to my last point: temperature fluctuation. Many don’t realize it, but a corked bottle of wine slowly breaths air in-and-out over time. As the temperature of the wine bottle changes from day to night or even summer to winter, the wine expands a little and contracts a little. This small amount of expansion and contraction causes tiny amounts of air to be either sucked into the wine bottle or pushed out of the wine bottle. The amounts are so small as to be undetectable, but the effects add up over time.

Now, apply this principal to a 5 gallons bottle of wine. A change in temperature has a much bigger effect. The amount of air involved is no longer undetectable. A slight contraction or expansion multiplied by 25 times a wine bottle’s volume can be noticed. It can also cause a problem by way of pushing your tapered cork or rubber stopper out of the opening, leaving your wine exposed to who knows what.

For this reason there are two things I recommend doing in addition to the above: 1) Keep the temperature as stable as possible while storing the wine in a carboy. 2) Wire down the tapered cork or rubber stopper. You can use a bailing wire of some sort. Tie it around the neck of the bottle then strap it across the top of the stopper with some needle-nosed pliers.

Gary, there is absolutely nothing wrong with bulk storing wine in a carboy. It is a great way to handle the long-term storage and aging of a wine. It also allows you to bottle the wine when you are ready to bottle the wine. Just keep it full and the temperature stable.

Happy Winemaking,
Ed Kraus
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Ed Kraus is a 3rd generation home brewer/winemaker and has been an owner of E. C. Kraus since 1999. He has been helping individuals make better wine and beer for over 25 years.

Using Wine Conditioner To Sweeten Your Wines

Posted on January 15, 2020 by AIH

I like sweet tasting wine. I always add a pint of your wine conditioner before bottling to my wines. Is that all I need to add before bottling or do I need to still add the potassium sorbate?

Fred (Occidental, CA)
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Hello Fred,

Glad to hear that the Wine Conditioner is doing the job for you. It provides a very simple way to sweeten your wine. Just pour it into the wine, to taste. You don’t need to worry about your wine re-fermenting in the wine bottles, popping corks or anything like that.

To answer question about the Wine Conditioner and adding potassium sorbate, it’s a matter of how much of the Wine Conditioner you use. If you’re using a whole container of Wine Conditioner to a 5 or 6 gallon batch of wine, then no, you won’t need to add any potassium sorbate. But, if you are only using some of the bottle, you need to pay a little attention.

Here’s the specifics: as long as you use at least 1/3 of the container of Wine Conditioner in a 5 or 6 gallon batch of wine, you will be fine. There will be enough potassium sorbate in the wine to prevent it from fermenting the new sugars. But, if you use less than 1/3 of the bottle to the wine, you will need to add a dose of potassium sorbate along with the Wine Conditioner to prevent a re-fermentation from occurring.

“Use more than 1/3 bottle, no potassium sorbate.
Use less than 1/3 bottle, add potassium sorbate”.

It should also be noted that you should always add sulfites to the wine before bottle, regardless if you use any Wine Conditioner or not. Sulfites are sold in three forms: Campden Tablets, sodium metabisulfite and potassium metabisulfite. Adding a single dose of any of these three at bottling time will help to keep your wines fresh and free form spoilage.

Fred, I hope this answers your question about using Wine Conditioner in your wines. Basically, if you are using the whole bottle to a 5 or 6 gallon batch of wine, then the only other thing that needs to be added is the sulfites.

Best Wishes,
Ed Kraus
—–
Ed Kraus is a 3rd generation home brewer/winemaker and has been an owner of E. C. Kraus since 1999. He has been helping individuals make better wine and beer for over 25 years.

Sanitizing Wine Making Equipment With Bleach Or Ammonia

Posted on January 13, 2020 by AIH

I have a wine instruction book that says to use ammonia for sanitizing wine making equipment. I have some beer instructions that say to use bleach. I understand that is dangerous to use both. But is there a reason for the difference, or can I just use ammonia, or just use bleach.

Name: Ken L.
State: California
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Hello Ken,

I got to be honest with you. I wouldn’t use either one to sanitize wine making equipment.

There are so many excellent cleaners and sanitizers on the market today for the home winemaker to use – cleaners and sanitizers that are both safer and easier to use. It’s come to a point that sanitizing wine making equipment with bleach or ammonia seem almost ridiculous.

I used to use bleach all the time to sanitize my wine making equipment back in the 80’s. There were old wine making books on the subject out there that recommended doing so, but what I found is that bleach is a big hassle that requires contact time and lots and lots of rinsing.

Chlorine likes to cling to surfaces, so one rinsing is not usually enough. I have not ever used ammonia to sanitize bottles or equipment, but I can’t imagine it to be much better.

Today, there are sanitizers that are very quick and easy to use. Some only require you get your equipment wet with it. Then allow it to air-dry. In fact, the air-drying is when all the sanitizing is actually being done with these sanitizers. It’s an oxidative process that occurs as the solution evaporates. No rinsing required. They are much safer because they are oxidative, becoming completely innocuous with a little time.

I would suggest using a product called Basic A No-Rinse Cleanser to sanitize all your fermenters and other wine making equipment. As the name suggest it is a no-rinse cleaner and the one I like the best for sanitizing my equipment.

For sanitizing wine bottles I use sodium metabisulfite instead of the Basic A No-Rinse Cleanser. This is essentially because evaporation can not happen efficiently within the confines of a wine bottle – something that Basic A needs to do to work.

Sodium metabisulfite approaches sterilization a little differently. You mix up the solution as directed on the container and put about two inches in the bottom of each wine bottle and allow them stand up-right for about 20 minutes. Unlike the Basic A, the fumes rising off the solution is what does the sterilizing in this case.

One of the beauties of using sodium metabisulfite is that the wine bottles do not need to be rinsed at all. They just need to be drained. Whatever remains in the bottles as droplets or condensation is fine and will not hurt or affect the wine in any way. We have a great product for draining these wine bottles called a Bottle Tree.

Ken, if you still insist on sanitizing wine making equipment with bleach or ammonia, I would stick with the bleach. Use 1/4 cup to 1 gallon of water. Allow 20 minutes of contact time. Then rinse 3 times. The rinsing is the most important part.

When To Add Pectic Enzyme To Your Wine!

Posted on January 10, 2020 by AIH

Can I add pectic enzyme after the fermentation to clarify the wine? Is there a substitute or alternative I should use instead at this time?

Name: Paul D.
State: Idaho
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Hello Paul,

Thanks for the great question. Some beginning winemakers get confused as to when to add pectic enzyme to their wines.

What Is Pectic Enzyme?
The first thing that needs to be understood is that pectic enzyme is not a fining agent or a wine clarifier for wine. It does not clear cloudy particles out of a wine after a fermentation like fining agents. Pectic enzyme is a protein that breaks down pectin in the fruit.

Pectin is the gelatinous material in fruit. It’s the stuff that holds the fruit’s fiber together. It is also the stuff that causes the resulting fruit juice to have the appearance of being cloudy. This is known as a pectin haze.

Once the fruit is crushed and pressed, not only does it release the juice, but it also releases the pectin. The pectin is a highly complex carbohydrate, refracting any light that hits it. This gives the fruit juice a cloudy appearance.

The pectic enzyme is a protein that is capable of breaking down the pectin cells into carbohydrates that are less complex – something that does not refract the light and give the juice a cloudy appearance. Essentially, the pectic enzyme causes a molecular change in the juice. It does not do anything to clear out a substances like a fining agent would; it changes the molecular structure of what’s there so that light may travel more cleanly through it.

When To Add Pectic Enzyme To Your Wine?
As for winemaking, the optimum time to add pectic enzyme is right after crushing the fruit and before pressing. By breaking down the pectin cells at this stage, you are allowing more juice to release from the fruit’s fiber – a good thing for making wine. If you are not the one doing the crushing and pressing, then the second best time to add pectic enzyme to your wine is at the beginning of the fermentation. This will allow the pectic enzyme to do its thing while the wine fermentation is occurring.

Three Things To Note Here:

Pectic enzyme comes in different strengths, so you are better off using the dosage recommended on the package it comes in instead of following the amount called for in your wine recipe.

During a wine fermentation the wine yeast does produce some pectic enzyme of its own. This is why it is possible to have a clear wine without adding pectic enzyme, but you are playing cloudy roulette with your homemade wine by not adding it. Adding pectic enzyme to your wine gives you added insurance that you are going to have a clear-looking wine.
If you do end up with a cloudy wine after the fermentation and you’ve already cleared out all the physical particles with a fining agent such as bentonite or isinglass, your options are few. Pectic enzyme is much more effective during a fermentation than after a fermentation. Your only hope is to add another full dose of pectic enzyme directly to the wine and give it time (sometimes months) to work on breaking down the pectin cells. If you did not add a dose of pectic enzyme at the beginning of fermentation, then you can add a double-dose, now. Pectic enzyme works much slower after a fermentation has completed.

Unfortunately, there is no alternative or substitute for pectic enzyme. So if you think you need some, you’ll have to get some. Do not use gelatin from the store. It will not disperse as evenly and readily as gelatin offered by wine supply shops.

I hope I’ve answered your questions and given you a more complete understanding of what pectic enzyme is and what it does for the home winemaker. Just remember it is at the beginning of fermentation that you when you’ll want to add pectic enzyme to your wine. If that ship has sailed, you can add a double-dose of pectic enzyme after the fermentation.

If you’d like to read more you might want to take a look at Why Do Wine Recipes Call For Pectic Enzyme.

Happy Winemaking!

Should I Be Adding Sulfites Before Bottling?

Posted on January 8, 2020 by AIH

I made an apple cider and a apple/blueberry cider. Both are in the aging process (4 months before bottling). I have the apple cider in a 5 gal. oak keg and the blueberry on in a 5 gal. carboy. Should I be adding sulfites before bottling the wine?

Name: Mike in NY
State: NY
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Hello Mike,

If you are aging your wine in bulk, such as a carboy or oak wine barrel, we recommend treating the wine with potassium metabisulfite before the aging. So hopefully you’ve already treated it with some form of sulfite. This is to keep oxidation and spoilage down while in the bulk aging vessel.

Regardless if you have or not, we also recommend adding sulfites before bottling. This dose is to keep the oxidation and spoilage down while the wine is in the wine bottle. Sulfites want to leave as SO2 gas over time and during rackings, so it does need to be replenished at various stages. Here is more information about when to add sulfites to a wine.

Also at bottling time, you may also want to add potassium sorbate. This will also help to stop any type of organism from multiplying and spoiling your cider. Potassium sorbate is mandatory if you plan or sweetening back your cider before bottling, or there are still sugars in the wine leftover from the fermentation. Not adding it in these situations could result in a re-fermentation in the wine bottle. This would lead to either popping wine corks, or worse yet, exploding wine bottles.

Since your are making apple wine/cider I will also mention this: we also recommend adding ascorbic acid to help battle the oxidation issue when using apple juice. Apple juice/wine likes to turn brown very easy. Ascorbic acid will help to slow down the process and keep your cider looking pretty. The optimal time to add this is right before fermentation, but right now is better than never.

If you’d like to read a little more on this subject, you may want to take a look at Adding Campden Tablets To Homemade Wine. This is another post on this blog.

Adding sulfites before bottling is arguably the most import addition. It is the last time you will be able to do anything directly to the wine to keep it, so don’t skip it.

How Clear Should Wine Be Before Bottling?

Posted on January 6, 2020 by AIH

I have 2 batches of fruit wine in the secondary ferment stage, soon to be in for 6 weeks. when it comes to clarity, how clear should wine be before bottling? and if not clear enough, is there a product I can put in it, or should I let it sit a little longer? Pear and peach.

Name: Mr. Sellers
State: Illinois
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Mr. Sellers,

The short answer as to how clear your wine should be before you bottle is it should be crystal clear. It should look like a solid hunk of glass when in the wine bottle. There should not be any murkiness or cloudiness to the wine at all. Anything less is a compromise in the quality of the wine.

When you see a haze or cloudiness in a wine it is usually caused by yeast cells or particles still floating within the wine. The wine has not finished stabilizing or has not stopped fermenting.

The little packet of wine yeast that was added at the beginning will regenerate itself by about 100 to 150 times. That’s what you are are usually seeing when a wine doesn’t look clear. Wine yeast is finer than flour. Much finer than can be seen with the naked eye, but collectively it can give the wine this dull appearance.

If the wine is bottled in this condition you will typically end up with bottles of wine that will eventually have dusty deposits at the bottom and a yeasty, sulfur-like smell.

If you are not sure if the wine is clear enough to be bottled, the obvious thing you can do is wait. Give the particles more time to drop out on their own. There is nothing wrong with waiting. The wine will age nicely in bulk. Patience can be a virtue in this situation, however if you are not so patient there are some things you can do to speed things along.

As far as to how to clear a wine, the first thing you can do is treat it with bentonite. This is a wine clarifier or fining agent that is commonly used among wineries. Many wineries will automatically add it to the wine directly after the fermentation has completed. Bentonite is effective in dropping out significant amounts of floating yeast, excessive tannins and other proteins. What it is not good at doing is putting a final, brilliant polish on the wine. This is the glassy-look I referred to earlier.

To get a final polish, I would suggest using Kitosol 40. This is another fining agent that is particularly good at giving the wine a brilliant appearance, but unlike bentonite it is not good at dropping out large amounts of particles. This makes it a good partner to use after the bentonite — the yin to the yang so to speak.

When done, the wine should look beautiful. It should have a pure look about it. Light should glisten and glimmer through it. This is how clear wine should be before bottling.

Hope this helps you out.

Is It Necessary To Filter Wine Before Bottling?

Posted on January 3, 2020 by AIH

Do you have to filter wine before bottling it?

Name: Nancy
State: MN
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Hello Nancy,

Filtering a wine before bottling is not necessary. A wine will clear on its own so long as the fermentation did not go afoul, and acid and pH are in good balance.

Fining agents can even be added to the wine to help the settling process to happen more quickly and thoroughly. For example, if you are making wine from a wine juice kit, normally it will come with bentonite. This will aid in clearing process. The wine will look very clear!

So if this is the case, why do wine filters even exist?
The one thing that needs to be understood about filtering wine with a wine filter is that it is not designed to take the visual cloudiness out of the wine. The filter pads are much too fine for this. They will clog up – usually within the first gallon. Time, gravity and fining agents will take care of the cloudiness. Filtering wine before bottling is done to add a polish to the wine – to add luster and brilliance. It is done to make the wine more beautiful, not less cloudy.

When you filter a wine before bottling you also are taking the last bit of wine yeast out of the wine. This amount of yeast is completely invisible to the naked eye. Doing this helps the wine to be more stable. If the wine is filtered with the finest filter (1/2 micron), it will be considered fermentation stable. By the way, a micron is very small. There’s about 400 of them across a period you find at the end of a sentence in a typical newspaper.

If you are on the fence as to whether or not to filter your wine before bottling, I would suggest comparing your wine side-by-side with a commercially made wine of a similar color. Almost all commercially made wines are filtered. See for yourself the difference then decide if filtering is something you would like to do to your wines.

Using Artificial Sweeteners To Sweeten Wine

Posted on December 30, 2019 by AIH

I am a diabetic, but my doctor has suggested 2 glasses of wine a night. Can I use artificial sweeteners to sweeten my wines after the fermentation has stopped? Will it affect the aging after bottling?

Name: Frank
State: TX
—–
Hello Frank,

There is nothing that suggest that artificial sweeteners affect the aging process, or aging-chemistry, of a wine. So from this perspective it is fine to add artificial sweeteners to sweeten wine at bottling time. But there are some other factors that come into play, depending on what kind of artificial sweetener you are planing on using to sweeten your homemade wine.

Not all artificial sweeteners are the same:

Sweet’n Low™: the main ingredient is saccharin. Saccharin will artificially sweeten your wine, but it will not permanently mix with the wine. If given enough time, such as when aging, the saccharin will drop to the bottom. When commercial products, such as Tab used saccharin as a sweetener, they also added a binder to keep it suspended. Us home winemakers do not have this luxury available to us.

Equal™: the main ingredient is aspartame. This artificial sweetener will sweeten wine as well as it will sweeten coffee or tea. It does have an Achille’s heel, however it does not stay stable for longer periods of time. Once in a liquid, it will slowly start to lose its sweetening effect. This is why sodas sweetened with aspartame will sometimes taste bitter if they are too old or stored in the heat. While you can store your wine in extremely cool places to slow down the lose of sweetness, this extremely cool temperature will also slow down the natural aging process of the wine. A more minor consideration is that Equal™ also contains a small amount of dextrose (corn sugar) and maltodextrin. Both of these ingredients can cause a very small fermentation with in the wine bottle. Not enough to be a direct problem, but possibly enough the give the wine a detectable amount of effervescence. For this reason, if you do decide to use Equal™ to sweeten your wine, I would also recommend adding potassium sorbate to eliminate any re-fermentation within the wine bottle.

NutraSweet™: again the main ingredient is aspartame so you have the same stability issues as with Equal™, but NutraSweet™ also as a second artificial sweetener, neotame. This artificial sweetener is a little more stable than aspartame, so between the two, NutraSweet™ would be your best artificial sweetener to sweeten wine. It would stay sweeter longer in your wines.

Splenda™: the main ingredient is sucralose. Sucralose is a molecularly modified form of sugar. The sugar is altered in a way that makes it very hard for the body to metabolize. It’s main strength is that it is stable. If used in your wine, it will always remain just as sweet as the day you added it. It binds with the wine, so you don’t need to worry about it separating out such as with saccharin.The main downfall is that, if given enough time, the enzymes that are left over from your wine’s fermentation can break down some of the sucralose into a simple sugar. If there are still residual yeast cells in the wine, you could have a slight fermentation in the wine bottle because of this. Also, like other artificial sweeteners, Splenda™ has dextrose and maltodextrin added as bulking agents to keep if fluffy. Just like with Equal™, these can also contribute to the possibility of fermentation in the bottle, so again potassium sorbate is recommend to keep the wine stable.

Stevia: This is a natural ingredient derived from a plant. There are some winemakers that are claiming great success with sweetening their wine with this product. I do not know how stable it is, but I’ve heard no complaints with losing sweetness over time, nor have I heard complaints of re-fermentation in the wine bottle. Having said this, price seems to be a major issue. There are many brands that offer this product in varying forms. Some cut with sugar; some cut with maltodextrin. You want to get the stevia as pure as you can — at least 95%. Currently, brands that offer this form of stevia are commanding prices in the range of $0.80 to $1.00 per ounce. Depending on how much stevia you need to use to sweeten your wine, this could be cost prohibitive.

The best advice I can give you is to go ahead and use any artificial sweetener to sweeten wine you like, but don’t add it until you are ready to drink the wine. The effects on the wine are identical and you don’t have to worry about all the potential problems these artificial sweeteners can bring. If you have your heart set on sweetening the wine at bottling time, then I might consider stevia as a trial. Take a portion of the wine off, say a gallon, and sweeten that to see how you like it.

Thanks for the great question, Frank. Hope everything works out for you.

Ferric Casse & Protein Stability: Two Cases For A Cloudy Wine

Posted on December 27, 2019 by AIH

I’ve been making homemade wine for over 30 years. Good friend of mine got me started and he introduced me to E. C. Kraus. I purchased a starter kit from you guys in 1992. Best move that I ever made. That brings me to my story. I make cranberry wine every year and it usually comes out great. Last years batch went cloudy on me. The taste is great, it’s just cloudy (what’s left of it). I’m a little confused as to why. This is the first time this happened. It cleared up nicely. The S.G. was close to .990 and it was very clear. I always use potassium sorbate before bottling. I never had any bubbling when I pulled a cork.

Any advise would be appreciated. I will be bottling about 20 gallons of cranberry before June of this year.

Name: Dan
State: NJ
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Hello Dan,

Thanks for the kind words. They are greatly appreciated.

As for your cloudy wine issue, normally I would go through all the basic reasons for a cloudy wine: still fermenting when bottled; picked up sediment from the fermenter when bottling; did not use pectic enzymes in the wine, etc., but it sounds like you’re beyond all that.

So, short of someone playing tricks on you by adding something to your wine, there are only two more reasons I can think of for your wine being cloudy:

Protein Stability:
This is a situation where there is more protein in the wine than the wine can hold. Usually, the protein is in the form of tannin. The tannin is dissolved into the wine, but if the tannin is in excess, it can start to drop out of the wine as little dust particles. This can happen slowly over time, or more rapidly if the wine has been warmed up a few degrees. It will be visible as a fine powder or dust in the wine that slowly starts to form a deposit at the bottom of the wine bottle.

Excess protein/tannin in a wine is caused by over processing the fruit — in this case cranberries — or by leaving the fruit in the fermentation too long. Technically, cranberries only need to be cut in half for a fermentation. I understand that no one is going to sit at the kitchen table all evening cutting cranberries in half, but you want to process the cranberries in a way that does just about that. You could lightly crush them enough to burst the skin. What you don’t want to do is things like chopping them up in a blender or food processor. This is way overkill and releases way too much protein from the fruit. As for the fermentation, I would not leave cranberries in any longer than 5 days.

If this is what has happen you will want to put the wine back into a fermenter. Slightly warm the wine up for a couple of days, say to 80°F. This will encourage the particles to form. Then treat the wine with bentonite. This is a fining agent that will collect and drop out the particles. Rack the wine off the sediment, stir in a dose of sodium metabisulfite and bottle.

Ferric Casse:
This occurs very rarely, but I will bring it up here for the sake of completeness. This can occur if the water used to make the wine has a high iron content. If the water you used does not a have high iron content, don’t even bother reading the rest of this.

The iron in the water, if exposed to enough air, will interact with the protein in the wine causing either white phosphate particles or blue protein particles to form in the wine. Wines that are low in acid, or are stored at cool temperatures are more prone to ferric casse, but this can only happen when the iron content is high.

In this situation you should decant the wine. Put it back into a fermenter. The wine must again be treated with bentonite. Once the wine is completely clear, rack off the sediment and stir in ascorbic acid at the rate of 1/4 teaspoon per gallon. The ascorbic acid will help to lower the pH so that this is not likely to occur again. Then add a dose of sodium metabisulfite and re-bottle.

If I had to guess, you need to look into #1 above. This is by far the most common reason of the two. If you would like to read more about it, we have an article on our website that covers it in a little more detail.

“Use more than 1/3 bottle, no potassium sorbate. Use less than 1/3 bottle, add potassium sorbate”.

“Use more than 1/3 bottle, no potassium sorbate.
Use less than 1/3 bottle, add potassium sorbate”.