Fall Bright, The Winemakers
www.fallbright.comDundee, NY, USA, 607-292-3995
From Lalvin: Fermaid®
K is a blended complex yeast nutrient that supplies ammonia salts (DAP),
free amino acids (organic nitrogen derived from inactivated yeast), sterols, unsaturated fatty
acids, key nutrients (magnesium sulfate, thiamin, folic acid, niacin, biotin, calcium pantothenate)
and inactive yeast.
For best results, Fermaid K should be used in conjunction with an appropriate yeast rehydration
nutrient (such as Go-Ferm) to assure proper nutrition of cultured yeast from rehydration through
Fermaid K provides unsaturated fatty acids and sterols. These are important survival factors
needed to maintain alcohol resistance and permease activity. They also help keep volatile acidity
Nitrogen is needed for protein synthesis and to maintain cellular growth. Nitrogen from the
alpha amino acids contained in Fermaid K is utilized much more efficiently than from the ammonia
The cell wall fractions in Fermaid K absorb medium chain fatty acids that are toxic to the
yeast. They also provide nucleation sites to help keep the yeast in suspension.TO USE:
Fermaid K should be hydrated before adding to an active fermentation to avoid CO2 release and
overflowing of tanks and carboys, barrels. Use non chlorinated water.
Dose at 2 pounds per 1000 gallons! See below for us amateurs...
Add Fermaid (25 g/hL) at 1/3 sugar depletion or in two doses; (12.5 g/hL)
at the end of lag phase and (12.5 g/hL) at
1/3 sugar depletion.
IN SUMMARY: For normal amateur winemaking applications, the recommended
addition rate of Fermaid K is 4.5 grams (1 level teaspoon) per 5 gallons. Add
in split doses. The first dose is at the end of the lag stage, the second half dose is added
at 1/3 sugar depletion.
The end of the lag phase is just before the yeast starts an active initial
fermentation. When you see the initial bubbling, I would guess that it is nearing the
end of the lag phase. We do not have a test for this on an amateur scale. Add the first half
of the recommended dose.
Used your hydrometer to determine 1/3 sugar depletion for the addition of the
second half of the dose.
NOTE: DO NOT combine the Fermaid K with the re-hydrated yeast
slurry before inoculation. Put it in the main volume of juice after the yeast population has
had time to expand, which is the end of the lag stage.
Fall Bright Usage Conclusions:
4 1/2 grams per 5 gallons. Dissolve in water before
adding to an active fermentation. 1 level tsp. is ~4 1/2 grams.
If you put it in at 2 different times, split the
dose, see above, and do not double dose or add in addition to DAP.
We currently are using Fermaid K, non Kosher. It has come to our attention that certain yeast, such
as Cotes des Blanc and Red Star Premier Cuvée prefer the more varied components of a more complex
yeast nutrient like Fermaid K and can stall with just the DAP nutrient.References