I want to kill my yeast

[Antler24]

I've got a rum fermenter going using buccaneer bobs recipe. It's currently sitting with gen 7 ready to be racked off and gen 8 started. I've been using bakers yeast up to this point and it's been great just slow fermenting because my basement sits at 16-17*C. So I thought I'd try some Nottingham as its temp range is perfect for my basement.
I don't want to clean out and restart my fermentation over, can I just rack off the wash, dump a gallon or 2 of boiling water in to kill the bakers yeast, and start gen 8 with the Nottingham?

[masonsjax]

I don't see why not. The dead bakers would make for a great source of lipids, vitamin B, and other nutrients for the new family of yeast to chew on. Bakers yeast is grown on sugar/molasses though and may be better suited to that particular wash than notty. It's cheap to try it out though so I say go for it.

[Antler24]

I don't see why not. The dead bakers would make for a great source of lipids, vitamin B, and other nutrients for the new family of yeast to chew on. Bakers yeast is grown on sugar/molasses though and may be better suited to that particular wash than notty. It's cheap to try it out though so I say go for it.

Thanks I'm going to try it out as soon as I can get some Nottingham. Maybe I can use the article pfshine posted and create a bakers/Nottingham frankenyeast lol

[Tater]

would have to get all wash/mash to high enough temp to kill yeast

[masonsjax]

I think he's talking about racking off the wash to run, then killing the yeast cake that remains. A couple gallons of boiling water should be sufficient.

[Antler24]

would have to get all wash/mash to high enough temp to kill yeast

I think he's talking about racking off the wash to run, then killing the yeast cake that remains. A couple gallons of boiling water should be sufficient.

What Masonsjax said...

[Secale]

I bet if you put your fermenter in a 80-100°C hot water bath for 60 minutes the yeast would all die.

I wonder if placing it all in a bathtub and filling it with only hot water would do?

[Antler24]

I bet if you put your fermenter in a 80-100°C hot water bath for 60 minutes the yeast would all die.

I wonder if placing it all in a bathtub and filling it with only hot water would do?

Yeah that would probably work, but dumping gallon or 2 of boiling water is much easier than dragging the 20g fermenter w/yeast trub upstairs to the bathtub and back. I'd still have to heat the water on stove to get it 80*C.

[pfshine]

I'm pretty sure he wanted to ferment his wash. He just wants a different yeast strain now.

[Hillbilly Popstar]

Why do you need to kill the current yeast strain?

If you just pitch a yeast that is happier at those Temps it will consume more of the sugars than the slow acting yeast anyways. Why not just let em eat?

[pfshine]

Yeast competition can cause off flavors from stress. Also the ester profile is different for the two and he wants a specific taste.

[SoMo]

Boiling water or a campden tablet both will work, I've been using EC1118 and it does really well all the way down to 64*f, might be worth a shot. I've really enjoyed the fact that it works hard at room temp 72*-74*f and really gobbles the molasses up.

[kiwi Bruce]

Small suggestion Antler, Take a quart mason jar full of the old yeast and save it in the fridge. It is no longer true bakers yeast if you've done seven washes with it, the strain will have adapted to your brewing environment, to loose it now might be a big shame.... just saying Kiwi

[Hillbilly Popstar]

Yeast competition can cause off flavors from stress. Also the ester profile is different for the two and he wants a specific taste.

Well, I don't know how it works in the distilling world, but beer brewing often use mixed strains of yeast to mix and add the different flavor profiles or to gain a higher attenuation. In fact, whichever yeast is faster acting due to better conditions or genetic attributes, will have the most effect on the flavor profile. I have never heard of the yeasts somehow interacting to make anything other than what each would create individually.

Can you offer any science or cited sources for that being the case?

[masonsjax]

Good advice from Bruce. Definitely save a jar of the original yeast in your fridge for future use.

[KYMountainMan]

When I'm trying to kill yeast in winemaking I dose it down with 2 campden tablets per gallon of juice. That kills any residual yeast and keeps it from starting a secondary ferment in the bottles. I let it sit for 24 hours after applying, so it will wick off.

[still_stirrin]

When I'm trying to kill yeast in winemaking I dose it down with 2 campden tablets per gallon of juice. That kills any residual yeast and keeps it from starting a secondary ferment in the bottles. I let it sit for 24 hours after applying, so it will wick off.

Campden tablets (potassium or sodium metabisulfite) are a sulfur-based product that is used primarily to sterilize wine, cider and beer making to kill bacteria and to inhibit the growth of most wild yeast: this product is also used to eliminate both free chlorine, and the more stable form, chloramine, from water solutions (e.g., drinking water from municipal sources). Campden tablets allow the amateur brewer to easily measure small quantities of sodium metabisulfite, so it can be used to protect against wild yeast and bacteria without affecting flavour.

Yes, it will kill active yeasts and wild flora. Wine (fruit ferments) often use them to sterilize the fruits before fermentation.

But 2 tablets per gallon will also put a bunch of sulfur into your wash. Distilling that can cause corrosion in your still and leave you with a blue-green distillate. Treat sulfur salts with care.
ss

[kiwi Bruce]

There is a way of acid washing yeast to clean it before saving it. I've never done it so I don't know the prep. Maybe someone here has, it would be handy to know, Kiwi

[Wooday]

When I'm trying to kill yeast in winemaking I dose it down with 2 campden tablets per gallon of juice. That kills any residual yeast and keeps it from starting a secondary ferment in the bottles. I let it sit for 24 hours after applying, so it will wick off.

Campden tablets (potassium or sodium metabisulfite) are a sulfur-based product that is used primarily to sterilize wine, cider and beer making to kill bacteria and to inhibit the growth of most wild yeast: this product is also used to eliminate both free chlorine, and the more stable form, chloramine, from water solutions (e.g., drinking water from municipal sources). Campden tablets allow the amateur brewer to easily measure small quantities of sodium metabisulfite, so it can be used to protect against wild yeast and bacteria without affecting flavour.

Yes, it will kill active yeasts and wild flora. Wine (fruit ferments) often use them to sterilize the fruits before fermentation.

But 2 tablets per gallon will also put a bunch of sulfur into your wash. Distilling that can cause corrosion in your still and leave you with a blue-green distillate. Treat sulfur salts with care.
ss

SS,
Wikipedia in this case has an error
Campden tablets contain Potassium metabisulfite. By itself Kmeta won't stop an active fermentation.

When stabilizing wine, it's used along with potassium sorbate after a long secondary fermentation, after the wine has been racked off the yeast bed. The combo doesn't kill the yeast so much as keep the few remaining from reproducing.
It won't make a dent in an active colony of billions of yeast cells.

My vote is for boiling/pasteurizing the 2 gallons and starting with a huge starter of your new yeast.