Deactivating Yeast?

[Mandelynne]

Okay, so, I have a question... is there any way to deactivate the yeast without the use of chemicals? Thank you in advance!

 

[RPh_Guy]

Well, no, since literally everything is made out of chemicals. The honey sugars and flavors are chemicals. The yeast is made of chemicals and produces lots of chemicals from the chemicals in the honey. You're made of chemicals and the sensation of drinking mead causes release of chemicals in your brain to make you feel happy.

You do have options besides sorbic acid for stopping those pesky yeast:
- Allow them to die peacefully from alcohol poisoning, if you don't mind a high ABV.
- You could sterile filter (0.4 micron if I recall correctly). It is somewhat risky leaving unstable residual sugar.
- You could heat pasteurize. This may or may not have negative effects on the mead flavor and ethanol (chemicals).

Hope this helps. Cheers.

 

[madscientist451]

You're made of chemicals

A TV show from the 80's came to mind when I read the above:

https://www.imdb.com/title/tt1772372/

 

[NeverDie]

Okay, so, I have a question... is there any way to deactivate the yeast without the use of chemicals? Thank you in advance!

By deactivate, I assume you mean stop them from fermenting? From what I've read if you put them under enough pressure (say, 30 psi or more), you can stop them from fermenting--but you may (?) have to maintain the pressure for them to remain "deactivated". That's why pressure fermentation is typically no more than 15psi, and generally more like 10psi.

 

[NeverDie]

Supposedly you can also permanently deactivate the yeast using certain kinds of pulsed electric fields. However, I'm not aware of any home brewing equipment though that allows you to do that. You may have to DIY it. Also, IIRC, the voltages involved may be pretty high, and if so, you'd need to take precautions so that you don't deactivate yourself!

 

[balrog]

Supposedly you can also permanently deactivate the yeast using certain kinds of pulsed electric fields

OH, SWEET!

Add pulsed cross-beam lasers and magnetic fields and maybe we can send mead into the 9th dimension!

Sorry. It's early here. Back on topic.

 

[Rob2010SS]

I know you said no chemicals but hoping that RPh_Guy response changed your mind, a campden tablet and potassium sorbate would deactivate the yeast. I did this a couple of times and it had no detectable change in flavor that i could tell

 

[IslandLizard]

Supposedly you can also permanently deactivate the yeast using certain kinds of pulsed electric fields. However, I'm not aware of any home brewing equipment though that allows you to do that. You may have to DIY it. Also, IIRC, the voltages involved may be pretty high, and if so, you'd need to take precautions so that you don't deactivate yourself!

How about UV?

 

[bmd2k1]

Okay, so, I have a question... is there any way to deactivate the yeast without the use of chemicals? Thank you in advance!

Use a yeast like S04 that cold crashes Really well! (D47 does too...but takes bit longer)...then rack off the solid lees & keep your cider refrigerated. I Never use any chemicals & have had great results following this protocol. I've also given my ciders as gifts where it has no longer been refridge'd & have never had an issue.

Cheers & Good Luck [emoji111]

 

[Miraculix]

Use a yeast like S04 that cold crashes Really well! (D47 does too...but takes bit longer)...then rack off the solid lees & keep your cider refrigerated. I Never use any chemicals & have had great results following this protocol. I've also given my ciders as gifts where it has no longer been refridge'd & have never had an issue.

Cheers & Good Luck [emoji111]

First of all, mead forum.

And second, I wouldn't want to risk bottle bombs after years of aging. Your method is gambling at best.

 

[NeverDie]

How about UV?

Would it kill them all, or just a percentage? Would it change the flavor?

 

[bmd2k1]

First of all, mead forum.

And second, I wouldn't want to risk bottle bombs after years of aging. Your method is gambling at best.

The yeast doesn't care what it's fermenting - honey, apples, grapes or otherwise! Have ya tried this protocol? Best of luck 2 ya [emoji111]

 

[Maylar]

The yeast doesn't care what it's fermenting - honey, apples, grapes or otherwise! Have ya tried this protocol? Best of luck 2 ya [emoji111]

D47 is appropriate for some meads, but S-04 isn't. And your protocol requires continuous refrigeration after cold crashing - OK for cider, not OK for mead.

 

[Miraculix]

The yeast doesn't care what it's fermenting - honey, apples, grapes or otherwise! Have ya tried this protocol? Best of luck 2 ya [emoji111]

Why should I want to risk bottle bombs? Please don't promote such a practice as it is dangerous.
You end up with yeast in suspension. Not much but after enough time they will metabolise any sugar left and this will make bottles explode and people get injured. If you like to take the risk, that's fine. But please don't try to talk people into it.

 

[Darthbrewder]

Pasteurization is the best way to kill the your yeast to stop fermentation without the use of potassium sorbate with camden.

The amount of heat needed should not be enough to effect the flavor of your mead.

Obviously do your research so you can do this safely. You don’t want to put cold or room temperature glass into 130°F water.

Good luck!

 

[Miraculix]

Pasteurization is the best way to kill the your yeast to stop fermentation without the use of potassium sorbate with camden.

The amount of heat needed should not be enough to effect the flavor of your mead.

Obviously do your research so you can do this safely. You don’t want to put cold or room temperature glass into 130°F water.

Good luck!

I once did a direct taste comparison of pasteurised and non pasteurised cider, using the same batch of cider.

Without judging one as better and the other one as worse there was a not neglactable difference in taste between those two. I guess there will be a difference in mead as well, but I cannot say if it would make it taste better or worse ...

 

[NeverDie]

I haven't tried pasteurization to stop fermentation, but when I first started making mead I would heat pasteurize the must and then cool it before adding the yeast. Although I no longer do this (as the consensus seems to be), I nonetheless had some pretty good meads out of that.

I think I'd like to try heat pasteurizing to halt fermentation, just to see. If others have tried it already, I'd like to hear of their experience first though.

 

[Mandelynne]

Well, no, since literally everything is made out of chemicals. The honey sugars and flavors are chemicals. The yeast is made of chemicals and produces lots of chemicals from the chemicals in the honey. You're made of chemicals and the sensation of drinking mead causes release of chemicals in your brain to make you feel happy.

You do have options besides sorbic acid for stopping those pesky yeast:
- Allow them to die peacefully from alcohol poisoning, if you don't mind a high ABV.
- You could sterile filter (0.4 micron if I recall correctly). It is somewhat risky leaving unstable residual sugar.
- You could heat pasteurize. This may or may not have negative effects on the mead flavor and ethanol (chemicals).

Hope this helps. Cheers.

This made my morning. Thanks!

 

[Mandelynne]

OH, SWEET!

Add pulsed cross-beam lasers and magnetic fields and maybe we can send mead into the 9th dimension!

Sorry. It's early here. Back on topic.

 

[Mandelynne]

Well, no, since literally everything is made out of chemicals. The honey sugars and flavors are chemicals. The yeast is made of chemicals and produces lots of chemicals from the chemicals in the honey. You're made of chemicals and the sensation of drinking mead causes release of chemicals in your brain to make you feel happy.

You do have options besides sorbic acid for stopping those pesky yeast:
- Allow them to die peacefully from alcohol poisoning, if you don't mind a high ABV.
- You could sterile filter (0.4 micron if I recall correctly). It is somewhat risky leaving unstable residual sugar.
- You could heat pasteurize. This may or may not have negative effects on the mead flavor and ethanol (chemicals).

Hope this helps. Cheers.

Can you make it sweet after you let them die?

 

[bernardsmith]

When you stabilize the fermentation you can freely add more honey or any source of sugar to sweeten a mead or wine. Stabilization means that you have "neutralized" 100% of the yeast. Standard home practice is to use K-meta with K-sorbate. Commercial wineries might use sterile filtration to remove the yeast. Home filtration is possible but a) your mead needs to be absolutely clear of any particles otherwise you will just clog the filters and b) I am not sure that home filters provide you with the filter size you need to ensure that 100% of the yeast is removed. Removal of 99.99% is OK if your batch is small enough to be consumed in a very short while but if you plan is to age the mead then I think cells can reproduce in 90 minutes - so about 16 times each day and as you start with several billion cells you may find that you have a large enough population of viable cells to ferment your mead brut dry. Not a problem if you are aging under airlock but a disaster waiting to happen if the CO2 the yeast produce is trapped in corked bottles.

 

[RPh_Guy]

Can you make it sweet after you let them die?

Absolutely!
As we have suggested, sorbate and sulfite is by far the easiest and probably "best" way to do this.
These stabilization agents are not harmful, and affect on flavor is little to none. Actually sulfite protects your mead from oxidation, preserving the flavor.

If you decide to heat pasteurize, sweeten and then pasteurize the bottles immediately after bottling. This eliminates risk of contamination.

How about UV?

Good call, missed that option. UV doesn't penetrate far into water, so you need to run it through a device.
https://www.rainharvest.com/sterilight-s5q-pa-silver-series-6-gpm-uv-system.asp

I doubt this would affect flavor, but I'm not 100% sure.

Supposedly you can also permanently deactivate the yeast using certain kinds of pulsed electric fields. However, I'm not aware of any home brewing equipment though that allows you to do that. You may have to DIY it. Also, IIRC, the voltages involved may be pretty high, and if so, you'd need to take precautions so that you don't deactivate yourself!

I'm not really on board with electrocuting the yeast or keeping the mead in some kind of pressurized chamber.
These aren't practical/safe solutions but kudos for thinking outside the box.

 

[NeverDie]

Absolutely!
As we have suggested, sorbate and sulfite is by far the easiest and probably "best" way to do this.
These stabilization agents are not harmful, and affect on flavor is little to none. Actually sulfite protects your mead from oxidation, preserving the flavor.

If you decide to heat pasteurize, sweeten and then pasteurize the bottles immediately after bottling. This eliminates risk of contamination.


Good call, missed that option. UV doesn't penetrate far into water, so you need to run it through a device.
https://www.rainharvest.com/sterilight-s5q-pa-silver-series-6-gpm-uv-system.asp

I doubt this would affect flavor, but I'm not 100% sure.

I'm not really on board with electrocuting the yeast or keeping the mead in some kind of pressurized chamber.
These aren't practical/safe solutions but kudos for thinking outside the box.

Is there an easier/cheaper way to try the UV steralization? I was thinking maybe in a thin glass container (thin, so less blocking of UV) on a stir plate, with a UV lamp on one side. Eventually the stirring should run everything past the lamp, right? Of course, this would be for smaller batches, like maybe 1 gallon or less.

 

[RPh_Guy]

Is there an easier/cheaper way to try the UV steralization? I was thinking maybe in a thin glass container (thin, so less blocking of UV) on a stir plate, with a UV lamp on one side. Eventually the stirring should run everything past the lamp, right? Of course, this would be for smaller batches, like maybe 1 gallon or less.

I doubt you could reliably kill 100% of the yeast with this method, especially since large yeast particles are pulled to the center.

 

[RPh_Guy]

BTW, cold crashing and racking can be effective for eliminating yeast, depending on the strain.

It's definitely not a technique I'd recommend for beginners and it's not something I would do. You need to crash, rack, and allow to bulk age for a significant period of time to monitor gravity. Repeat as needed.
If you just want to crash, rack, and refrigerate like @bmd2k1, that's fine, but it's not necessarily shelf stable.

 

[JimRausch]

Is there an easier/cheaper way to try the UV steralization?

I have a steripen that I use for sterilizing water for backpacking trips. It does 1 qt at a time, and the water has to be clear. Of course, it's designed to get the few giardia spores and few bacterial cells in back-country water. I'm not sure how well it would do with the millions of yeast present in most meads/ciders/beers. Maybe I'll give it a try sometime. I have a microscope, and am well versed in using it. A pretreatment vs. posttreatment cell count could be interesting.

 

[JimRausch]

I do have another question that my post above made me think of. My procedure post fermentation is to rack every month or so, onto 1 Camden tab every other racking, until the mead or wine stays clear and is not producing any more lees. I assume that is cutting way down on viable yeast. Maybe next one I do, I'll take a look for viable yeast at each stage of racking, and at bottling time.

 

[Blacksmith1]

Is there an easier/cheaper way to try the UV steralization? I was thinking maybe in a thin glass container (thin, so less blocking of UV) on a stir plate, with a UV lamp on one side. Eventually the stirring should run everything past the lamp, right? Of course, this would be for smaller batches, like maybe 1 gallon or less.

Build a chamber using one or two of the uv lights from an HVAC system with an acrylic tube that fits your racking cane down the center. Slowly pump the liquid thru it.

 

[Mandelynne]

Is there any other stabilization agent besides sulfites? The reason for my question, is because I'm really sensitive, and don't want to flare (I have lupus).... but I suppose I could just try it and see...

 

[NeverDie]

Is there any other stabilization agent besides sulfites? The reason for my question, is because I'm really sensitive, and don't want to flare (I have lupus).... but I suppose I could just try it and see...

Potassium sorbate is one of the components you need, but it's not sufficient by itself.

If you want to avoid the artificial ingredients, you can drink it all in the moment (i.e. small batches) when it hits your target SG.

Not sure what effect freezing might have on mead. Haven't tried it, but maybe? It would surely halt the yeast process, at least while frozen. However, you might run out of freezer space, so it's less convenient.

Or the other alternatives that have already been mentioned.

 

[RPh_Guy]

Is there any other stabilization agent besides sulfites? The reason for my question, is because I'm really sensitive, and don't want to flare (I have lupus).... but I suppose I could just try it and see...

From my understanding it's the SO2 vapors that actually cause the issue. Therefore working with sulfite in any amount might be problematic. If you want to try it, I'd suggest adding 10ppm free sulfite. That's a small amount but should be adequate.

The above methods for sweet mead do work:
Heat
Cold
UV
Filter
High ABV

One method not mentioned: using a non-fermentable sweetener (e.g. xylitol) that doesn't require stabilization.

Alternately,
Do you want to try an experiment? You could possibly use sodium benzoate as the sole stabilizing agent (no sulfite).
FDA limits it to 0.1%, so that's 0.1g/100mL = 3.79g per US gallon.

https://en.wikipedia.org/wiki/Sodium_benzoate

https://www.amazon.com/Sodium-Benzoate-2lb-USP-grade/dp/B010G4IPNS/

Benzoic acid is both fungistatic and bacteriostatic. Seems like a good alternative and shouldn't contribute off-flavor.
You need to remove as much yeast as possible before trying to stabilize with a preservative.

Hope this helps. Cheers

Not sure what effect freezing might have on mead. Haven't tried it, but maybe?

I'd be up for a mead slushie!

 

[Darthbrewder]

Check this video. I know this is for cider but it might help you decide on what your preferred course of action might be.

 

[Boots5598]

I once did a direct taste comparison of pasteurised and non pasteurised cider, using the same batch of cider.

Without judging one as better and the other one as worse there was a not neglactable difference in taste between those two. I guess there will be a difference in mead as well, but I cannot say if it would make it taste better or worse ...

Mead usually needs to be back-sweetened using additional honey - the sugars from which will restart fermentation unless the yeast is rendered inert.