YAN adjustement

[CarlD]

This is my first blend of hybrid grapes . 30lbs of petite pearl , 16 of marquette and 10 of frontenac . 17 L of must
My prefementation number are brix :19.5 , ph :3.19 YAN :132 ppm
I want to bump YAN to 300ppm for my vivace yeast from renaissance.
since Fermaid-K is 13% N by weight then 1.29g/L x 130 mg N/g = 167.7PPM

1.29g per L of Fermaid-k seem big . What is the maximum dosage of Fermaid-K?

 

[Johnd]

This is my first blend of hybrid grapes . 30lbs of petite pearl , 16 of marquette and 10 of frontenac . 17 L of must
My prefementation number are brix :19.5 , ph :3.19 YAN :132 ppm
I want to bump YAN to 300ppm for my vivace yeast from renaissance.
since Fermaid-K is 13% N by weight then 1.29g/L x 130 mg N/g = 167.7PPM

1.29g per L of Fermaid-k seem big . What is the maximum dosage of Fermaid-K?

25 g/Hl is the recommended dosage, normally split into two separate doses, 12.5 g/Hl at the end of the lag phase, 12.5 g/Hl at 1/3 sugar depletion.

 

[EdThrockmortin]

You need DAP, not more Fermaid.

 

[stickman]

To get up to 300 YAN, my calculation indicates a total addition of about 9g fermaid K and 10g DAP. I know the yeast supplier recommends a YAN of 275, but they don't indicate a brix level, usually a lower brix requires less YAN, so you may only need 200 to 250 YAN at 19 brix.

 

[EdThrockmortin]

Frankly, I get my YAN to ~300 independent of Fermaid K considerations. A healthy must has 200-400 YAN. I see that as what the substrate needs (must science) and then the Fermaid for the yeast (yeast/fermentation science, note the Fermaid instructions are independent of Brix, grape or yeast type) to thrive. I'm not so concerned with "too much N" as I'd like the largest yeast expansion and healthiest yeast population (too much YAN would = spoilage organism risk, but just make sure you dont go crazy) vs. the NIGHTMARE of a stuck ferment. My 2 Cents