First, you must make sure the mead has stopped fermenting. Mead is such a slow fermenter that it may appear completely done, yet continue to ferment after bottling. This can turn a still mead into a sparkling one; it can even produce enough pressure to cause the bottles to explode. Exploding bottles– “glass grenades”–aren’t funny. They’re unpredictable and very dangerous.
To be sure the mead is done fermenting, take hydrometer readings spanning a week or more and be sure the readings are not still falling. Dry meads will also finish at a gravity below 1.000. As a mead finishes, it will “fall clear”–the initial cloudiness will settle out. Be careful, though, because being clear is not enough.
Choose appropriate bottles for the type of mead. Sparkling mead (carbonated, like champagne) will require a sturdy bottle, either sparkling wine (which are thick enough to take the higher carbonation) or returnable beer bottles. Beer bottles should be crown-capped. Sparkling wine bottles can be corked if you use champagne corks and wire them down. American sparkling-wine bottles can be crown-capped just as beer bottles can. European sparkling-wine bottles cannot be reliably crown-capped–they have a crown-cap lip, but it’s the wrong size for standard caps.
Still meads (uncarbonated, like normal wines) may be bottled in regular wine bottles with standard corks, or in crown-capped bottles as above. Since pressure isn’t an issue, almost any bottle with an airtight closure can be made to work. Bear in mind, though, that the appearance of your bottles is part of the first impression when you serve your mead.
Mead that has finished fermentation and is then bottled will be “still” (flat). Sparkling mead is “primed” by adding a small amount of sugar at bottling time to produce a short renewed fermentation so that it is carbonated. For predictable results (again, to avoid “glass grenades”), you should first let the mead finish fermenting in the carboy, then add just the amount of sugar needed to carbonate it. Bottling a mead before it finished fermenting (in hopes of capturing just the right amount of carbonation in the bottle) can lead to under- or over-carbonation, and even in the best case won’t give the mead a chance to finish clearing before bottling. A normal amount of priming sugar is about 4 ounces by weight for five gallons.
If you want a still, sweet mead, you can use a lot of honey and let the mead ferment until the yeast finally gives up (because of the alcohol), then bottle. However, if you do this, it is strongly advised that you “stabilize” the mead with potassium Sorbate to prevent the yeast from re- starting and slowly fermenting after bottling. Mead-makers have seen sweet meads stop fermenting and remain stable for months, but re-start slowly and produce dangerously carbonated meads in bottle. Note also that Sorbate won’t stop an active fermentation; it will only prevent dormant yeast from re-starting.
Store the bottles in a cool dark place. Mead is not as sensitive as beer to light (unless you have hops in it), but should not be left in bright light.