"Natural" fermentation

[cooltouch]

I ran across an interesting situation several weeks ago. I had a bit of leftover grape juice from some homemade wine I'd made, using baker's yeast. Which actually turned out to pretty good, but that's another story. What was interesting was, when I opened the bottle it gave off a woosh! of compressed air, and a white froth appeared along the top surface of the juice. I gave it a sniff, and sure enough. It was wine! I tasted it, and it was very dry, so I just dumped it into the jug of wine I'd previously made.

But it got me to thinking, and recalling articles I've read on fermenting wine using wild yeast. So for my next batch, I decided to deliberately ferment my wine this way. I started with a half gallon of grape juice, to which I added a cup and a half of sugar. Then I bought some grapes at the local supermarket, selecting bunches that had that "frosty" look, which I hoped would contain a decent amount of wild yeast. I crushed these grapes, added their juice to the mix, stuck a perforated balloon on the top of the jug, and then forgot about it for about a month. If the fermentation caused the balloon to inflate, I missed it, so I don't know how long it stayed inflated.

Last night I opened the jug and took a sniff. Yep! It smelled like wine. So I siphoned it off into a second, clean jug. There was quite a bit of sediment left behind. What I immediately noticed as I was siphoning the wine was that it had a brown, rather tawny color (I used some clear tubing). Hmmm, I was thinking. Might I have wound up with a sherry of some sort? I kind of doubted it.

So, I poured a glass. Wow. It actually tasted great! Definitely not a sherry. Somewhere between a cabernet and a merlot as far as sweetness/dryness goes. I don't own a hygrometer, so I don't know what the ABV is, but based on the buzz I got from a few glasses of it last night, I'd say it's at least 12%.

One of the things I was worried about was that the wrong kind of wild yeast would find its way into my fermentation. The other being that no fermentation would take place. Well, it definitely was not the wrong kind of yeast.

This first experiment with wild yeast was so successful that I think I'll just do it this way from now on.

If there's anything you might like to add or comment on regarding this process, I'd like to read what you have to say. I'm still a virtual newbie at all this, after all.

 

[tingo]

I wouldn't invest much time or money into this concept. I admire your sense of adventure, after all that is what winemaking is all about, but you are dealing with a recipe for disaster. Since wild yeast are very sensitive to So2 means that you will have to omit using it and therefor open a whole new can of worms. That part aside wild yeast is risky. There are 1000s, if not more, types of yeast that can do all sorts of funky things to wine. Many people have success with fermenting this way but since you are a beginner I would put serious thought into how much you are willing to lose for a possible roll of the dice. Either way I wish you the best of luck and you might want to google "natural winemaking" or something of that nature to pick up on precautions, tricks, or secrets to this style of winemaking.

 

[cooltouch]

Thanks for the feedback. Hey, all I have to lose is the price of a half-gallon of grape juice and the price of a couple of bunches of grapes. I'm using 1 gallon containers that previously contained distilled water, which I now keep instead of throwing them away when they're used up. I may be a beginner, but I have done some reading on the subject of wine making. And yes, I'm aware of the thousands of varieties of wild yeast and that many of them can turn a batch of sugared juice into a funky mess. But I felt that I was stacking the odds in my favor by 1) keeping everything as clean and sanitary as possible, and 2) trusting that the yeast that was on the grapes that I crushed to be the right kind of yeast.

There is a method to my madness. I am interested in seeing if I can duplicate the way ancient wines were made. I've just begun to read up on this subject and already have decided to change things. Ancient methods usually involved fermentation in open vats, where dirt and other contaminants could enter the wine. I think I'll continue to use closed containers, thanks very much. Beyond this first fermentation, it appears that the ancients didn't do much more. I'm still reading up on techniques used by more recent cultures, such as the Romans. The Romans had a variety of much more sophisticated techniques that they employed in their winemaking. Dunno how many of their processes I'll try, but it will be interesting to try a few of them.

 

[vernsgal]

keep us posted on the outcome. I am curious

 

[tingo]

Would it be possible for you to post your logs and findings on this sight each time a batch is done fermenting? Im quite interested.

 

[robie]

Lots of wine around the world is still fermented with native (resident) yeast.

Whatever yeast did the fermentation will eventually take permanent residence in your wine making area. Each time you ferment in the future, if you don't specifically add yeast, that same resident yeast will get into the wine and do the job.

If you have been using bread yeast and you don't add any other cultured yeast, it would be safe to assume that bread yeast is what will be fermenting all your future wine. This is especially true if you make bread anywhere near where you are making the wine. The fact that you seal up your juice before you start fermentation may potentially mean you are not using your resident yeast, but it is hard to say for sure. To avoid the resident yeast, you would have to prepare the juice and seal it up before you place it in your wine making area.

That said, if the wine truly is being fermented by bread yeast, it is never going to be as good as it could be, if you use a true wine yeast.

Sounds like you are enjoying your experiment, so have fun and let us know how it goes.

 

[jswordy]

I'm with robie and all, more power to anyone who wants to make wine any way they want. People have made wine this way in prisons a long time. They steal a piece of bread to get the yeast and away they go.

But if you want predictability in your winemaking and you strive for specific wine flavors and compounds that go beyond the very general and vague description "it tastes like wine," which after all describes both Boone's Farm and Chateau Yquem, then you are going to have to go at minimum with a cultured yeast in a starter solution at a buck a pouch.

I'd be very careful just dumping one batch into another. You could have a good batch of wine that is ruined by dumping a bad batch into it. I'd keep them separate.

Also, as long as you are going this way, be darned sure you are CLEAN and sanitized (using very hot water if nothing else), because native and bread yeasts are weak little buggers and a few bad bacteria can disrupt the whole process.

 

[ohbeary]

CT, one "Roman" wine treatment I would avoid is adding lead salts (lead acetate) to sweeten your "natural" wine.

 

[gordini]

I use wild yeasts often, as well as commercial yeast. You do have to be very careful. Watch your ferment temperature, and make sure that you use at least 70ppm free sulphur in the must to kill the nasty yeasts. Sorry, if you can't measure free S02, you'll have to do the conversion from camden tablets or meta.

Lead acetate.... I've often wondered if some experimenter once put lead in molten glass ( to make an in-built sweetener) and accidentally made crystal glass.

 

[tingo]

Gordini,

1. Are wild yeast more sensitive to high temperatures?

2. Wouldn't 70ppm kill all wild yeast? Or just weak strains?

 

[gordini]

Tingo... The term "Wild Yeast" is applied to all yeast naturally floating around your shed/home/winery, on the fruit, on the utensils and containers, anything that comes in contact with the wine making process. At 70ppm, I have been assured that the more sulphur resistant strains are able to dominate the ferment. These are also appropriate alcohol tolerating wine making yeasts. I've had wild yeast fermenting in the refrigerator and at well over 30deg C ( 80F). Anywhere in the range of 16 to 25 deg C is fine.

 

[robie]

Never think of k-meta as actually killing any yeast, even though I assume a small percentage of them may actually die. Think along the lines of it stunning and weakening the yeast so other yeast can come in afterward and over-power the weakened yeast.