Why honey is a poor food for yeast

Honey is a beautiful thing: complex sugars, delicate aromas, and a natural preservative. But for yeast, it's a bit like being handed a bowl of sugar and told to build a house. Honey lacks the nitrogen, vitamins, minerals, and lipids that yeast need to multiply and stay healthy. In a grape must, those nutrients come from the skins and pulp. In honey, they're simply not there. That's why a mead can start fermenting like a train and then grind to a halt, leaving you with a sweet, sticky brew that refuses to budge. The fix is not more yeast; it's better feeding.

What to look for in a yeast nutrient

Not all nutrients are created equal. The simplest is diammonium phosphate (DAP), which supplies assimilable nitrogen. It's cheap and effective, but used alone it can cause yeast to race ahead and then crash. Better blends include yeast hulls (dead yeast cells that provide lipids and sterols), thiamine (vitamin B1), and magnesium sulphate. These micronutrients help yeast build strong cell walls, which is crucial when alcohol levels rise. Avoid nutrients that contain urea; they can produce unwanted compounds. If you can only find DAP, pair it with a teaspoon of yeast hulls per batch. A balanced commercial blend is the easiest route for most home mead makers.

Timing your additions: the staggered approach

Dumping all your nutrient into the must at pitching time is a common mistake. Yeast can only use so much at once, and excess nitrogen can be toxic or leave a lingering bitterness. Instead, stagger your additions. Start with a dose when you pitch your yeast (after rehydrating it). Then add more at the one-third sugar break — the point where your hydrometer reading has dropped by a third of the way to your target gravity. For a must starting at 1.100 and finishing at 1.000, that's around 1.067. Add a final dose at the two-thirds break (around 1.033). Stir gently to dissolve and degas. If you're using a nutrient blend, follow its instructions, but this rhythm works for most meads.

How much to use (without guesswork)

For a 4.5-litre (one UK gallon) batch, a good starting point is 1 teaspoon (about 3 grams) of a balanced nutrient at pitch. Then add ¼ teaspoon at each of the two sugar breaks. If you're using DAP alone, keep the total to 1 teaspoon per 4.5 litres, split across the three additions. For high-gravity meads (above 1.120), you can go up to 1.5 teaspoons total, but no more. Always dissolve the nutrient in a little must or warm water before adding — never dump dry powder onto the yeast. And remember: more nutrient isn't better. Overshooting can feed spoilage organisms and leave off-flavours.

Why temperature matters

Yeast nutrient uptake is an enzymatic process, and enzymes are fussy about temperature. If your must is below 15°C, yeast become sluggish and cannot use the nutrients you so carefully added. If it's above 25°C, yeast race through the nutrients, produce fusel alcohols, and often stall later. The sweet spot for most mead yeasts is 18–22°C. Keep it stable — swings of more than a few degrees stress the yeast. If you're fermenting cool, add your nutrient earlier and consider warming the must slightly. If you're fermenting warm, add later but watch for a hot, solventy smell. A simple stick-on thermometer on your demijohn is worth its weight in gold.

Rescuing a stalled batch

It happens: you check the gravity and it hasn't moved in days. Don't panic. First, warm the must to 20°C and gently swirl to rouse the yeast. Then add a small dose of nutrient — ¼ teaspoon per 4.5 litres — along with a pinch of yeast hulls. Give it 24 hours. If there's still no action, rehydrate a fresh packet of yeast with a little nutrient and pitch that. Avoid adding a huge dose of DAP at this stage; it can shock the yeast. Sometimes a stalled mead just needs time, warmth, and a gentle nudge. With the right nutrients and a steady temperature, most batches will finish dry and clean.