Was using 1 gallon glass bottles for my main fermenter. Recipe used Sams honey, water and natural yeast on some raisins. Don't have the recipe in front of me, but it was high honey mix. Maybe a 1:1 dilution with water. But could have been a 1 : 2? Anyway, it was a high honey concentration.
It seemed to ferment OK in primary. After 15 months in gal jug it would not clear. I noticed the airlock had black mold in it. So decided it had enough time to work. Tasted the mix and it was sweet, but offered very little alcohol taste. Trashed it.
When cleaning out the glass jug, I rubbed around the inner neck of the bottle to clean out some of the reside. It was very greasy and would not wash off my fingers with water. Had to use lots of soap to cut the grease.
How can honey, water and some natural yeast make grease? I'm wondering if the Sams honey had adulterants in it?
Could be "adulterated" honey, or it could be from the raisins. Sometimes raisins are available coated in corn syrup or the like. I've noticed a very greasy like residue after using raisins that had this corn syrup coating. Dunno what else it might've been. If it was indeed due to the raisins having a corn syrup coating, I'd suggest soaking them in water a couple of times until there is no more greasy/oily stuff on them before using. It works pretty well, and then that gunk doesn't wind up in the batch.
As for the batch, so sad that you decided to dump it! Most times you can salvage batches like that with some vigorous champagne yeast. A naturally occurring yeast can be unpredictable, and you did it no favors by starting with such a high gravity must. I realize it was only Sam's Club honey and only a 1 gallon batch, but dumping a batch should really only happen if you know you can't save it. Even then, most mead failures can be used as a unique marinade/cooking wine. Just something to keep in mind for future batches.
Find what you like, and hone it to perfection.
And don't serve dodgy mead!
Certain wild yeast strains can also make different types of films that have a weird texture. Here is a link to a bunch of photos: http://www.homebrewtalk.com/f127/pel...ection-174033/
It can look pretty gross if you are not used to sour beer fermentations. It doesn't sound like your case is this dramatic, but I've definitely seen wild yeast make a layer of what looks like grease floating at the top of your brew, and it will cling to the glass some.
Raisins are often coated with vegetable oil so they don't clump... although the only time I've had it be an issue was when I used 8 lb for a gallon...
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