Stages of Fermentation

Mead moves through several distinct phases from pitch to glass. The total time varies enormously — a light session hydromel may be drinkable in 6–8 weeks; a high-gravity traditional may need a year or more. What matters is following each phase in order and letting the mead tell you when it's ready to move on.

The durations above are indicative. Real batches vary widely depending on gravity, yeast strain, temperature, and nutrient management. Use them as expectations, not deadlines.

Pitching means adding active yeast to the prepared must. For dry yeast — which most home meadmakers use — proper rehydration dramatically improves yeast health compared to sprinkling dry yeast directly into the must.

Immediately after pitching, aerate the must vigorously for 1–2 minutes. This is the last point at which oxygen is actively beneficial. See the Aeration & Degassing guide for how and why.

After pitching, yeast cells enter the lag phase — a period of metabolic preparation before visible fermentation begins. The yeast are rehydrating, repairing membranes, synthesising enzymes, and beginning to multiply. No CO₂ is produced yet and there is nothing visible happening in the vessel.

Resist the urge to add more yeast or nutrients at this stage. Lag phase is normal. The yeast is working — you just cannot see it yet.

Once the lag phase ends, active fermentation begins. You will see vigorous CO₂ production, a foamy head (krausen) forming on the surface, and lees — dead yeast cells and sediment — beginning to collect at the bottom. Gravity drops rapidly during this phase, which typically lasts 1–4 weeks depending on gravity, temperature, and nutrient availability.

This is the busiest period for the meadmaker:

• Follow your SNA schedule — nutrient additions at 24, 48, 72, and 96 hours after pitch
• Aerate before each early addition and degas before adding nutrients
• Monitor temperature — most mead yeast work best between 15–25°C
• Take gravity readings every few days as activity slows, not during peak activity

Primary fermentation is complete when the gravity reading is stable. Take a reading, wait 5–7 days, and take another. If the reading has not changed, the yeast have finished the fermentable sugar available to them.

Racking means transferring the mead from one vessel to another, leaving the lees behind. Rack after primary fermentation is confirmed complete — two stable gravity readings, 5–7 days apart.

Use a siphon (auto-siphon or simple racking cane with tubing) to transfer the mead into a clean, sanitised vessel. A narrow-neck carboy, demijohn, or similar vessel minimises headspace and reduces oxygen exposure. Fill to within a few centimetres of the bottom of the bung.

• Avoid splashing. From this point forward, oxygen is the enemy. Transfer from the bottom up, not by pouring.
• Don't leave mead on thick lees too long. A thin yeast layer is normal and harmless. A thick, compacted lees layer left for months can contribute autolysis off-flavours — a yeasty, meaty, or sulfurous character from decomposing yeast.
• Record the volume after racking. You will lose a little mead with each rack — knowing what you have helps with nutrient calculations and topping up.

Secondary fermentation is a slight misnomer — by the time you rack, there is usually very little active fermentation remaining. The secondary phase is primarily clarification and early conditioning. Gravity continues to drop slightly, the mead clears as yeast and proteins fall out of suspension, and some of the harsher early-fermentation character begins to mellow.

This is also the stage for adding secondary ingredients if you are making a variant style:

• Fruit additions for melomels — secondary fruit additions preserve volatile aromatics lost during active fermentation
• Oak cubes or spirals for oaked meads — start with a short contact time and taste frequently
• Spices or herbs — add in a sanitised muslin bag for easy removal

Take gravity readings monthly. Some meads are genuinely done in secondary within 4–6 weeks; others benefit from 3+ months. Let clarity and taste guide you, not a fixed schedule. A second rack may be needed for very cloudy meads or those with heavy fruit additions.

Young mead often tastes harsh, hot, and unpleasant. This is the "rocket fuel" phase — a normal characteristic of freshly fermented, high-alcohol liquid. The ethanol and various fermentation by-products need time to integrate. Tasting at week 3 and concluding the batch has failed is the most common meadmaker mistake.

Indicative bulk aging minimums:

Before bottling, stabilise the mead if you plan to back-sweeten — see the stabilisation guide. If you want a sparkling mead, see the carbonated meads guide before deciding your approach.

There is no universal date at which a mead becomes ready. Three signals together are more reliable than any single indicator:

1. 1

   Stable gravity — Two readings at least 5–7 days apart showing no change. The number should match or be close to the predicted final gravity for your yeast strain.

2. 2

   Visual clarity — The mead has cleared to your satisfaction — no active haze, sediment falling rather than floating. Some styles (particularly fruit meads) may never be completely brilliant without fining, which is fine.

3. 3

   Taste — The mead is pleasant to drink. Harsh alcohol heat has integrated. The balance of sweetness, acidity, and flavour is where you want it. This is the most honest test — trust it over any timetable.

When all three signals line up, the mead is ready to bottle. If one is still off — the gravity is stable but it tastes hot, or it tastes great but still has a visible haze — give it more time. Patience is the most reliable technique in meadmaking.