# Must temperature before pitching yeast



## mariodolphins1010 (Oct 2, 2017)

Hi guys, crushed a new batch of grapes yesterday (10 cases) 

I added metabisulphite yesterday at 11am. It almost 24 hours later pitching yeast would be the next step but the must is at 13 degrees Celsius. Should i wait for the must to warm up a little more before pitching yeast.


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## Johnd (Oct 2, 2017)

mariodolphins1010 said:


> Hi guys, crushed a new batch of grapes yesterday (10 cases)
> 
> I added metabisulphite yesterday at 11am. It almost 24 hours later pitching yeast would be the next step but the must is at 13 degrees Celsius. Should i wait for the must to warm up a little more before pitching yeast.



I have made wine from frozen must numerous times, and typically sprinkle my yeast on top once the must reaches 55 F (12.78 C). As the must an yeast warm up to room temps, it gets going just fine.


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## mariodolphins1010 (Oct 2, 2017)

Is sprinkling a better option than hydrating at this must temperature. Should i shut off the heater?



Johnd said:


> I have made wine from frozen must numerous times, and typically sprinkle my yeast on top once the must reaches 55 F (12.78 C). As the must an yeast warm up to room temps, it gets going just fine.


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## balatonwine (Oct 2, 2017)

mariodolphins1010 said:


> Is sprinkling a better option than hydrating at this must temperature.



I consider dry yeast hydrating, then letting that cool to must temp, the best option at any temperature.


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## mariodolphins1010 (Oct 2, 2017)

And you dont touch the must for 24 hours after sprinkling?



balatonwine said:


> I consider dry yeast hydrating, then letting that cool to must temp, the best option at any temperature.


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## Johnd (Oct 2, 2017)

mariodolphins1010 said:


> Is sprinkling a better option than hydrating at this must temperature. Should i shut off the heater?



You may do either, you can sprinkle right on top and just let it go. I normally don't stir the must until a little bit of a cap forms.

As far as heating your must, it depends upon the ambient temperatures in your fermentation area. If your fermentation area is 70 - 75 F, the must will warm to that temp on its own, you may use the heater to warm it more quickly if you like.

If you choose to rehydrate the yeast, you can do it that way as well. Follow the instruction for rehydrating on your yeast package, but make sure that you allow the temperatures between the yeast starter and must to equalize prior to pitching. Too big of a temperature swing can be problematic for the yeast, you don't want to dump a 75 F starter into a 55 F must. Slowly add some of the cool must to the yeast starter, allowing the temps to equalize before pitching the starter.


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## balatonwine (Oct 2, 2017)

mariodolphins1010 said:


> And you dont touch the must for 24 hours after sprinkling?



First, I do not sprinkle. I remove some must, warm it separately, add the yeast, stir and mix, let it start in a warm space, move it to the cellar to cool, then add it to the main must usually the next day.

Otherwise, no, there is no need to touch the must if one has added the appropriate amount of k-meta; any significant biological activity should be arrested for 24 hours. Of course, I have a cellar, so can attest this is true under ideal cellar temperature conditions. I can not say what happens, for example, in a less than ideal area like a warm garage. Adjust as needed. But the OP seems to have a pretty low must temperature, so I would not expect any problems waiting for the hydrated yeast to cool to ~must temperature.


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## mariodolphins1010 (Oct 2, 2017)

Thank-you , i just sprinkled the yeast and I wont touch it until the cap forms a little.



Johnd said:


> You may do either, you can sprinkle right on top and just let it go. I normally don't stir the must until a little bit of a cap forms.
> 
> As far as heating your must, it depends upon the ambient temperatures in your fermentation area. If your fermentation area is 70 - 75 F, the must will warm to that temp on its own, you may use the heater to warm it more quickly if you like.
> 
> If you choose to rehydrate the yeast, you can do it that way as well. Follow the instruction for rehydrating on your yeast package, but make sure that you allow the temperatures between the yeast starter and must to equalize prior to pitching. Too big of a temperature swing can be problematic for the yeast, you don't want to dump a 75 F starter into a 55 F must. Slowly add some of the cool must to the yeast starter, allowing the temps to equalize before pitching the starter.


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## Turock (Oct 2, 2017)

Yeast can be slow to take off on cold must. We like the must temp to be around room temp. And if this is a red, it's beneficial to heat the must to around 80 degrees for better extraction of color.


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## mariodolphins1010 (Oct 3, 2017)

Hi, its almost 30 hours later, the must started bubbling this morning and still bubbling but very slowly.

There is noticeable dry yeast still on top of skins that haven't made contact with any juice yet. Do I leave this alone or push that down at this point?




mariodolphins1010 said:


> Thank-you , i just sprinkled the yeast and I wont touch it until the cap forms a little.


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## Johnd (Oct 3, 2017)

mariodolphins1010 said:


> Hi, its almost 30 hours later, the must started bubbling this morning and still bubbling but very slowly.
> 
> There is noticeable dry yeast still on top of skins that haven't made contact with any juice yet. Do I leave this alone or push that down at this point?



Go ahead and give it a gentle punchdown.


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## mariodolphins1010 (Oct 4, 2017)

update: Cap is slowly starting to form and bubbling is a little more than yesterday, must temp is 19 degrees Celsius.


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## mariodolphins1010 (Oct 4, 2017)

mariodolphins1010 said:


> update: Cap is slowly starting to form and bubbling is a little more than yesterday, must temp is 19 degrees Celsius.



Must is still at 19 celcius but more activity. Should I turn on the heater?


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## mariodolphins1010 (Oct 4, 2017)

Hi, must is currently at 19 brix and fermenting slowly at 20 degrees Celsius

Ambient temp has been consistent at 21 degrees

Are things moving the way they should?


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## Johnd (Oct 4, 2017)

mariodolphins1010 said:


> Hi, must is currently at 19 brix and fermenting slowly at 20 degrees Celsius
> 
> Ambient temp has been consistent at 21 degrees
> 
> Are things moving the way they should?



I’m assuming this is a red wine must since you have skins and a cap. 21 C is fine, but a smidge low for my personal preference. I shoot for 75 F ambient, and spikes up into the low to mid 80’s during the height of fermentation, to aid in extraction. 

You may continue as you are if you like.


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## mariodolphins1010 (Oct 5, 2017)

as of 7am the must is boiling alot. Brix dropped to 6 and must temp is 30 Celcius



Johnd said:


> I’m assuming this is a red wine must since you have skins and a cap. 21 C is fine, but a smidge low for my personal preference. I shoot for 75 F ambient, and spikes up into the low to mid 80’s during the height of fermentation, to aid in extraction.
> 
> You may continue as you are if you like.


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## Johnd (Oct 5, 2017)

mariodolphins1010 said:


> as of 7am the must is boiling alot. Brix dropped to 6 and must temp is 30 Celcius



You’re getting close to the end, things should be slowing down, temps will ease back. Let your temps fall back to the mid 70’s as you near completion, almost time to press!!


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## mariodolphins1010 (Oct 5, 2017)

How do I let temperature drop? 


[and QUOTE=Johnd;663880]You’re getting close to the end, things should be slowing down, temps will ease back. Let your temps fall back to the mid 70’s as you near completion, almost time to press!![/QUOTE]


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## Johnd (Oct 5, 2017)

mariodolphins1010 said:


> How do I let temperature drop?
> 
> 
> [and QUOTE=Johnd;663880]You’re getting close to the end, things should be slowing down, temps will ease back. Let your temps fall back to the mid 70’s as you near completion, almost time to press!!


[/QUOTE]

What is the temp in the fermentation area?


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## mariodolphins1010 (Oct 5, 2017)

19 Celsius 


What is the temp in the fermentation area?[/QUOTE]


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## Johnd (Oct 5, 2017)

mariodolphins1010 said:


> 19 Celsius
> 
> 
> 
> What is the temp in the fermentation area?


[/QUOTE]

That’s 66F, so it’ll drop back on its own as the heat generated by fermentation subsides. Once the skins are gone, after pressing, that’ll also help with heat release.


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