We are making a home made batch of huckleberry wine for halloween. We filled a Cleaned milk jug 3 quarters of the way with water, then we drained the juice, put it in the milk jug, and added a small package of yeast, and 1 cup of sugar. The Milk jug is 3 quarters of the way full still. It's been sitting for almost 4 weeks. We now have this weird film over the top layer of liquid. I don't have a picture, but it looks to me like a powdery white layer. I can see the little granules, that makes me think it looks like the yeast and sugar is what is on the top. Every one around me believes that it is mold. I want to find out if it is mold or not. The jug smells fine, the wine smells like it should at this stage, but every one keeps telling me it's mold on the top. Can anyone help answer this question for me?
What you're describing is called a colony of cells called a pellicle. According to Home Brew Talk's wiki:
A pellicle is a lumpy, slimy white film that is formed by some strains of wild yeast, notably brettanomyces, during fermentation. A film on your beer in the fermenter or the bottle almost always indicates an infection, unless you have intentionally added brettanomyces to your beer. Follow the instructions in the brettanomyces page for cleaning and replacing your equipment.
The presence of a pellicle is not in itself a good or bad thing. It's more common in cider, wine & meads than in beer with the exception of beers with Brett yeast.
One upside to having a pellicle is they can be anaerobic, which means they are air-tight and potentially protect your brew from a variety of environmental hazards.
- Keep sanitary work conditions
- Monitor your brews (Take measurements & notes!)
- Smell your brew: if it smells moldy, it very well could be.
- Use a turkey baster to draw a small sample and taste the liquid (a little won't kill you)
- Head to your local homebrew store to get some basic tools for experimenting.
- Keep on trying stuff, and don't let an infection get you down.