The Ultimate TOSNA 2.0 Mead Nutrient Calculator
Do you want to make the best mead possible? Fermenting great mead requires giving your yeast the right nutrients at the right time. The Tailored Organic Staggered Nutrient Addition (TOSNA 2.0) method ensures a smooth, efficient fermentation without off-flavors or yeast stress. This calculator helps you determine exactly how much Fermaid O and GoFerm you need—in grams and teaspoons—so even home mead makers without gram scales can use it!
Step 1: Enter Your Mead Details
Nutrient Calculation Results
| Measurement | Value |
|---|---|
| Final OG | |
| Recommended Yeast Weight | |
| Total Fermaid O | |
| Total GoFerm | |
| Yeast Hydration Water |
Staggered Nutrient Schedule
| Timing | Fermaid O (g & tsp) |
|---|---|
| At Yeast Pitch (Day 0) | |
| ~24 Hours (Day 1-2) | |
| ~48 Hours (Day 3-4) | |
| ~72 Hours (Day 5-6) |
FAQ: Understanding Mead Nutrients
| Nutrient | Purpose |
|---|---|
| Fermaid O | An organic yeast nutrient derived from inactivated yeast cells. Provides amino acids, peptides, and vitamins without inorganic nitrogen. |
| GoFerm | A yeast hydration nutrient that boosts yeast health at pitching, improving viability and fermentation performance. |
| Fermaid K | A blend of organic and inorganic nitrogen (DAP). Not used in TOSNA 2.0 due to risk of fusel alcohols. |
| DAP (Diammonium Phosphate) | A fast-acting inorganic nitrogen source. Not used in TOSNA 2.0 because it lacks amino acids and vitamins. |
Assumptions
- Batch Size: Assumes the batch size represents the volume of must going into the fermenter.
- Honey Contribution: Uses a conversion factor of 0.035 for honey weight per gallon to estimate final OG.
- Yeast Pitching Rate: Assumes a gravity‑dependent yeast pitching rate (e.g., roughly 2.5 g/gal at 1.080 OG, adjusted with a 0.05 g per gallon increase per OG point above 80).
- GoFerm Calculation: Assumes GoFerm is dosed at 1.25 g per gram of yeast required.
- Nutrient Conversions: Uses conversion rates of 2.6 g per teaspoon for Fermaid O and 2.0 g per teaspoon for GoFerm based on empirical data.
- Staggered Additions: Nutrients (Fermaid O) are divided into four equal additions over the first 72 hours.
- Uniform Mixing and Temperature: Assumes complete mixing and ideal heat transfer during yeast rehydration and nutrient addition.
- Preheated Equipment: Assumes all equipment is preheated (or at ambient temperature) so that vessel temperature doesn’t affect the calculations.
We here at Boomchugalug.com want to thank the good people at Scott Labs and the fermentation community for developing the fine TOSNA 2.0 protocol.
We’d also like to thank them for their responsible use of acronyms, like TOSNA (Tailored Organic Staggered Nutrient Addition)…
…as opposed to our own less responsible naming suggestions, such as:
- Terribly Overcomplicated System for Nutrient Addition (TOSNA)
- Totally Obsessive Science for Nutrient Application (TOSNA)
- Thoroughly Overthought Steps for Nourishing Alcohol (TOSNA)
- Trust Our Scientific Nutrient Application (or else) (TOSNA)
And we’re sad to say they immediately rejected our further suggestions:
- NERDS – Nutrient-Enthused Researchers Designing Staggering-additions
- LUSER – Layered Urea Staging Enhances Results
- SMUT – Sequential Mineral Uptake Technique
- BUFFOON – Balanced Uptake of Fermentation Factors Optimizes Outstanding Nutrients
- IDIOT – Incremental Dosing Increases Optimal Transformation
- SCREWED – Sequential Calculated Ratios Ensure Worthwhile Ethanol Development