Wild Texas Mustang Grape Fermentation

[lukeb723]

I started a 5 gallon batch of Mustang grape wine about 2 weeks ago and still haven't seen the vigorous ferment like using commercial yeast. I did have a little mold but scooped it out and started mixing several times a day and it hasn't returned. This is my first wild fermentation so I'm not sure if everything is normal. I read that Mustang grapes are high acid and low sugar. Maybe I should rack and add the sugar water? Thanks.

[Tim Hall]

Mustang is extremely high in acid (I'm in Texas, and am familiar with this grape). You'll definitely need to add some kind of sugar to balance it, or else you'll just get pucker. You might check out Jack Keller's website for recipes. I'd be inclined to cut it with as little water as possible - perhaps a heavy sugar syrup, if you don't think you can get dry sugar alone to dissolve well.

I've heard the mustang can make a really good wine as long you balance out the acidity. But I only have experience with it in preserves. We also get native muscadine in east Texas, which is naturally a very sweet grape. I think these two grapes come to harvest at different times, but I've always imagined a blend of these two would make a really nice wine.

[Tim Hall]

Sorry I missed the "2 weeks" part. You might want to taste what you've got. This is a pretty long time for it to go without showing signs of fermentation. I'd personally be inclined to intervene with a commercial "killer" yeast at this point to make sure you're not just making vinegar or grape-kraut.

[lukeb723]

Tim

I am using the Czech recipe from Jacks website. There has been fermentation taking place but just no heavy bubbling. The grapes had been frozen for a couple of weeks before I decided to ferment them. But being in the bucket for two weeks should be ample thaw time. Everything smells fine. there just isn't a vigorous ferment. I'd hate to go commercial with it but not sure what else to do.

[Tim Hall]

You know, those grapes tend to be so acidic, it wouldn't surprise me if it they aren't just a little tough to get started. At a certain acidity level it becomes hard for even acid-loving bugs to work.

If you start to get a nail-polish (ethyl acetate) odor going on, even very slightly, I'd pitch something like k111 or champagne and get it under an airlock. This is a precursor to vinegar and indicates oxidation - it won't ferment out.

[lukeb723]

They still smell like grapes. If I go commercial should I campden first or just toss in the yeast?

[Tim Hall]

hmmm...good question. I've never used campden personally.

I hate to tell you to abandon the wild thing. It may still turn out fine. But if it were me, I'd also hate to loose 5 gallons of good must. (Unless you can use 5 gallons of good vinegar). Safest approach would be to drop campden, and pitch commercial yeast. In other words, if you were to go all the way, playing it safest, campdem seems warranted. But you'd be surprised how fast a killer strain can take off without assistance.

Is this still crushed pomace/skins, or have you pressed it? If it isn't pressed yet, pressing it might be just enough added oxygenation to kickstart the ferment. (Assuming it's not an over-acidity problem, or just dull yeast.)

[lukeb723]

Well vinegar would't hurt my feelings as long as it was safe to cook with. Although wine was on my agenda. I haven't added the 2.5 gallons of sugar water yet. Maybe that would help reduce the high acid level? I think I'll give the natural yeast a chance to take hold though and risk winding up with vinegar.

[Tim Hall]

Maybe that would help reduce the high acid level?

Yes, definitely. I don't know what Jack's procedure calls for, but any alcohol ferment I do that calls for adding "hot" fermentables like sugar, I like to add this up front, in the beginning. Adding extra fermentables later in the fermentation can stress the yeast, causing them to express higher alcohols...NASCAR-grade ethanol is not desirable in my opinion ;)

[Tim Hall]

BTW, years ago my parents, having no experience with wine making, tried to make Mustang wine from the wild vines growing on the fences around our property. They ended up only making vinegar, but it was excellent vinegar and made for a very good marinade.