Question

Nitrogen Balance: Your fermentation has 87 ppm in the juice before you begin your fermentation, and you would like to end up with 250ppm total Yeast Assimable Nitrogen by the 1/3 sugar depletion of your fermentation. Figure out how much you need to add along the way: You add 5 ppm YAN at inoculation...how much do you still need to add by 1/3 sugar depletion?

Answer 1

Yeast requires nitrogen for fermentation .YAN stands for Yeast Available Nitrogen. It is a measure of the amount of nitrogen available to the yeast in sugar solution.

the YAN required for frementation is given - Brix level multiply by the suggested multiplication ratio for the yeast we are using.

In the later stages of fermentation, yeasts lose the ability to intake nitrogen because of inhibitory effects of alcohol.

At inoculation-If grape YAN is below 150 ppm Then rest of YAN because active frementation occur