Stopping Fermentation

[rebusify]

Hi guys, the question I have is about making sure fermentation has stopped. My kit says I need to add in the potassium sorbate which will keep the yeast from reproducing but it won't stop them from continuing to eat up the sugar so besides lowering the temp, what other way can I be sure to stop fermentation? I've read that filtering would do it but do I really want to filter each racking? Thanks in advance.

 

[cmason1957]

As a home winemaker, you don't have a good way to stop fermentation. However, it stops on it's own when the yeast runs out of sugar. How do you know when that happens, you use your hydrometer. If it is below 1.000 (some say 0.996 for insurance) and holds the same for about three days in a row, your fermentation has stopped.

 

[rebusify]

Since I'm going to cold stabilize couldn't I just rely on the cold temp to kill them? I plan on cold stabilizing after fermentation (racking once first) for about 2 weeks then racking and then filtering. The reason I ask is because I don't want to have to wait 3 more days to tell if it's done.

 

[cmason1957]

Cold temps do not kill yeast, they just inactivate them. Cold stabilizing should not be done until you have clear wine. As to waiting 3 more days, Winemaking is a procrastinators best hobby. the three best tools you have to make good wine are patience, patience, patience.

But it is your wine, you can do whatever you want to it. Most of us try to suggest best practices, feel free to follow your own path.

 

[rebusify]

Yes and suggestions are greatly appreciated for I don't know much about this other than what I'm learning here and you and others have done me a great service by putting forth your suggestions.

 

[rebusify]

Since I have you here. When would you do campden tablets? I'm reading that I should add 6 tablets (6 gallons) while racking and then when I bottle. Is that what you would do?

 

[CDrew]

Let it ferment all the way to dry. Dry means no residual fermentable sugar. Rack at the end of that process. Once you've racked the clean wine and it isn't fermenting any longer, then add your Sulfite. I'd recommend you use another source of SO2 than Campden tablets. Use Potassium metabisulfite. Campden tablets sound like some old school legacy pharmacy thing that requires a mortar and pestle.

I don't really know about kits, but why do you need Sorbate? If the yeast has converted all the sugar to alcohol, the sorbate is not needed. Leave it out. It can only make things worse, unless you are trying to make a sweet wine like a port. I'd leave it out.

 

[cmason1957]

Since I have you here. When would you do campden tablets? I'm reading that I should add 6 tablets (6 gallons) while racking and then when I bottle. Is that what you would do?

Many kits these days come with a combined package of potassium metabisulphite and potassium sorbate. If your kit has one of those and you plan to follow kit instructions as far as timelines, you will not need to add campden tablets. But let's assume it didn't include that, then after fermentation is complete, you would add the campden tablets and yes one per gallon. If you do not agree for longer than there months, you probably don't need to add more at bottling, if you do bulk age, then yes more at bottling time.

I'll second that potassium metabisulphite is easier to use for the 6 gallon sized batches (1/4 tsp), but for single gallons campden (one per gallon) is easier.

 

[rebusify]

The kit didn't come with potassium metabisulphite so I'll be adding after fermentation. Thanks for that. One point of confusion though. You said "6 gallon sized batches (1/4 tsp)" and 6 tablets crushed up would be a lot more than 1/4 tsp or did I miss something?

 

[rebusify]

I misread. Sorry. Got it.

 

[rebusify]

Let it ferment all the way to dry. Dry means no residual fermentable sugar. Rack at the end of that process. Once you've racked the clean wine and it isn't fermenting any longer, then add your Sulfite. I'd recommend you use another source of SO2 than Campden tablets. Use Potassium metabisulfite. Campden tablets sound like some old school legacy pharmacy thing that requires a mortar and pestle.

I don't really know about kits, but why do you need Sorbate? If the yeast has converted all the sugar to alcohol, the sorbate is not needed. Leave it out. It can only make things worse, unless you are trying to make a sweet wine like a port. I'd leave it out.

I'm trying to mimic my favorite Oregon Rose which is the Pinot Noir Rose and they call it "Bubbles". It's from a company called "A to Z" and it's a little sweet. What they do is blend 90% Pinot and 10% Chardonnay. Not sure if that's how they get that hint of sweetness or if they're doing something else. They won't tell me and I've given them so much money!

 

[Scooter68]

Campden tablets have a filler in them along with the K-Meta. Otherwise a Campden tablet made of ONLY Potassium Metabisulfite would be REALLY small - 1/6 that 1/4 oz. (Compressed too)

 

[Rice_Guy]

* pasteurization is done by cider folks to kill yeast
* I have done some with ale yeast which were supposed to stop at 8% alcohol, but wasn’t impressed
* some yeast lit basically says run a weak/ 12% alcohol yeast. and chill combined with a high dose of meta.

Our choices aren’t very good

 

[rødvinselsker]

Like you, just getting started in winemaking. While I don't have a rose' on the radar yet I have thought about it so was interested in your question. Found this at WinemakerMag, but it sounds like if the goal is to achieve a slightly sweet wine, then the choices are to arrest fermentation or back sweeten after it goes dry. From what I've read, the latter is the process most home winemakers likely use. Hope this helps.

"Arrest the fermentation or add sugar later: You’re going to want a little residual sugar in this wine, perhaps 0.30–3.0%, depending on your tastes. Most white Zinfandels are perceptibly sweet, though I like mine a little drier. This can be achieved by arresting the fermentation (using chilling, an SO2 addition, and filtration), though for home winemakers it’s easier and more foolproof to add sugar or grape concentrate and then potassium sorbate to inhibit renewed fermentation in the bottle."

https://winemakermag.com/wine-wizard/making-white-zinfandel

 

[winemaker81]

@CDrew -- campden tablets are also made with K-meta these days. This was pointed out to me recently.

@rebusify -- I agree with @camason1957 -- Campden are great for 1 and 2 gallon batches, but if you're doing 5-6 US gallon kits, potassium metabisulfite (K-meta) is easier to use, and (I think) a fair amount cheaper. I haven't made anything less than 3.5 gallons in a long time, so I not sure about the prices.

Regarding sorbate -- if the wine is dry (SG 0.998 or less), there is no need to add it. I use sorbate only when back sweetening wine or if for some reason it won't ferment out.

As mentioned, some kits are now combining the sulfite & sorbate. I put those packets in a drawer (saved for a fruit wine I am sweetening) and add my own K-meta. It's not wrong to add sorbate to a dry wine, but it is unnecessary.

 

[Scooter68]

Stopping an active fermentation is a lot like swimming upstream in a river. It can be done but it takes a lot of work and you still may miss your target point.
Not mention anytime you have to add chemicals you potentially may get unexpected results.

I don't bother to even try and stop a ferment before it wants to. Let it roll and back-sweeten later.

AND be aware of your starting points (SG and Potential ABV) A lot of the time folks make a mistake and get that SG to high to start with and then try to stop the ferment.... Do it right the first time and avoid the extra work and headaches. If you get the SG too high either add more juice to lower it or make a dessert wine out of it.