Fermaid® K

Fall Bright, The Winemakers Shoppe
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 completed fermentation.

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 levels low.

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 salts.

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.

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.   Mix half of the dose in 1/4 cup of non chlorinated water.  Add in split doses.  The first (half) dose is added 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.  It may be just a matter of a few days.  Pay attention. 

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.

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.