Free Mead Staggered Nutrient Addition (TONSA) Tool
Calculate total Yeast Assimilable Nitrogen (YAN) requirements and four-stage organic Fermaid O additions (TONSA 3.0) to achieve clean, fast, ester-rich mead fermentations.
🍯 Batch Gravity & Yeast Demand
📊 TONSA 3.0 Dosing Schedule
| Stage | Timing | Fermaid O | Critical Action |
|---|---|---|---|
| Addition 1 | 24 hrs post-pitch | -- g | Degas must thoroughly before adding |
| Addition 2 | 48 hrs post-pitch | -- g | Degas & aerate must |
| Addition 3 | 72 hrs post-pitch | -- g | Degas & aerate must |
| Addition 4 | At 1/3 Sugar Break | -- g | Final dose! Cease aerating after this point |
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Tested hardware and components for high reliability
1. Why Honey Demands Staggered Nutrients (YAN)
Unlike malted barley (beer wort) or crushed wine grapes, honey is pure diluted sugar almost entirely devoid of natural nitrogen, vitamins, and minerals. Typical honey must contains only $20 - 35 ext{ mg/L}$ of Yeast Assimilable Nitrogen (YAN), while healthy yeast requires between $150 ext{ and } 350 ext{ mg/L}$ to ferment cleanly without stress.
Starving yeast cells produce volatile sulfur off-flavors—primarily hydrogen sulfide ($H_2S$, smelling of rotten eggs) and excessive fusel alcohols (higher alcohols like isoamyl alcohol, responsible for intense jet-fuel burning sensations and severe hangovers).
2. The TONSA 3.0 Organic Protocol
Developed by award-winning meadmaker Bray Denard and perfected by the mead community, TONSA 3.0 (Tailored Organic Nutrient Staggered Additions) relies exclusively on Fermaid O (autolyzed yeast extract). Organic amino nitrogen is assimilated much more gently and smoothly by yeast than harsh inorganic salts like DAP (Diammonium Phosphate): $$ ext{Target YAN (ppm)} = ext{Brix} imes M$$ Where $M$ is the tier multiplier: Low $= 3.8$, Medium $= 4.4$, High $= 5.0$, Very High $= 5.6$. Total Fermaid O (grams) for the batch is: $$ ext{Total Fermaid O (g)} = rac{ ext{Target YAN} imes ext{Volume (L)}}{65}$$ Divided equally across 4 doses at 24 hours, 48 hours, 72 hours, and the 1/3 sugar break.
3. The 1/3 Sugar Break & Wine Aeration Rules
The 1/3 Sugar Break occurs when one-third of the fermentable sugar has been converted: $$SG_{1/3} = OG - rac{OG - 1.000}{3}$$ For an initial $1.110 ext{ OG}$ must, the 1/3 break is reached at $1.073 ext{ SG}$. Prior to the 1/3 sugar break, vigorous daily degassing and oxygenation build healthy yeast biomass. After the 1/3 sugar break, stop all aeration, as oxygen introduced into alcohol causes oxidation and staling.
Frequently Asked Questions
Why should I dissolve Fermaid O in warm water before adding to the mead?
Adding dry powder directly into actively fermenting mead introduces thousands of nucleation sites, causing violent CO2 degassing that will instantly erupt out of the carboy in a sticky mead fountain ("mead geyser"). Always dissolve the powder in 50mL of warm water or must first, and stir gently.
Why does TONSA 3.0 prohibit DAP (Diammonium Phosphate)?
DAP provides a massive spike of inorganic ammonium ions that causes yeast to consume sugar too rapidly, creating excessive fermentation heat and harsh fusel alcohols. Once the alcohol rises above 9% ABV, yeast can no longer absorb DAP anyway, leaving residual inorganic salts that taste metallic and nourish spoilage organisms.
How do I convert Specific Gravity (SG) to Brix?
Brix represents the percentage of sugar by weight. A standard approximation is: Brix = (143.254 * SG^3) - (648.67 * SG^2) + (1125.8 * SG) - 620.38. For example, 1.110 SG is approximately 25.9° Brix.
What if my mead reaches the 1/3 sugar break before 72 hours?
If your fermentation is exceptionally fast and passes the 1/3 sugar break on day 2 or 3, add all remaining nutrient doses immediately at the 1/3 break. Never add nitrogen nutrients after the 1/3 break, as yeast cannot assimilate them.