Fermenting Soda

Question

Years ago I attempted to ferment Mountain Dew (about a decade ago so my recount of the details may be a bit off). My goal was to have a drink with similar carbonation, similar flavor, and reasonable amount of alcohol. Talking with some coworkers who were amateur wine makers, they suggested using a champaign yeast. I took a 5 gallon carboy, filled it most of the way up with Dew, added yeast, and added granulated sugar until it was sugary enough for that particular yeast to thrive. I don't recall how much sugar was added but I was shocked that the Dew itself didn't register high enough by itself when tested.

When the fermentation was complete, something to make carbonation was added, it was bottled, and put in a cool dark place for a month or so. When I finally tried it, the results were a bit disappointing. There was a flat, yeasty, slightly bitter & alcohol taste, but the Dew flavor was almost nonexistent. All in all it was a fun experiment that I couldn't wait to try again.

My questions is this... I got a Mr. Beer kit as a gift and I thought about trying my "Dew Brew" again. Is there anything I can do to get better results (more of a Mountain Dew flavor with better carbonization)? Do I need different equipment? If the problem was that the Dew was already fairly diluted (relative to most pre-fermented liquids) would it work to go get a bag of the syrup that is used in soda fountains?

thanks!

Answer 1

Your best bet is going to be start with a simple beer/wine/mead recipe, depending on what you prefer, to get your alcohol. Then, you can throw in a liter or two of Mt. Dew if you want, for flavoring, but keep in mind that sodas are generally only about 10% - 20% fermentable, so actual soda will only water down your brew. The key, however, is finding a concentrated flavoring to add, like this mountain dew candy flavoring:

http://www.amazon.com/Mountain-Dew-Flavor-Candy-Flavoring/dp/B0000DK64P

You could also throw in some lemon or lime zest, maybe a pinch of anise, and other things to replicate the Dew taste.

I don't recommend using much Mt. Dew though, for the following reason:

If you were to pitch perfectly healthy yeast, like that harvested from the krausen of an actively fermenting beer, into pure Mt. Dew, I think you'd find that you wouldn't get more than about 1% ABV from fermentation. It's just not very fermentable, and it doesn't usually taste much like the original soda after the yeast have their way with it.

Going back to recipe formulation, I might start with something like 11 lb of pale 2-row malt (or 7.5 lb LME), an ounce of a noble hop like Saaz, and the aforementioned flavorings.

If you brew it, let us know how it turns out!

Answer 2

Why don't you just add vodka or something? Fermenting seems a bit elaborate when all you want is basically Mountain Dew with some alcohol in it.

Answer 3

I think your biggest problem might be the preservatives (sodium benzoate and others) used by Pepsi when making Mt. Dew. Some of those are sure to give the yeast some trouble growing and fermenting your drink, or at the very least will lead to additional stress on the yeas that produce off flavors.

Wikipedia has a good list of ingredients in Mt. Dew, along with links to individual pages with explanations about many of them. Perhaps you could try making your own Mt. Dew syrup from the list of ingredients, but leave out some of the preservatives and more obscure industrial chemicals to help the yeast ferment.

Answer 4

Chris Colby, the editor of BYO magazine has what appears to be a mild obsession with using Mountain Dew in beers. There are a couple of recipes that have appear in the magazine: Beelzeboss (Oct 2007 issue) and Mt. Brew (Mar/Apr 2005 issue).

His experience seems to be that the preservatives do slow fermentation somewhat, but they are at a level designed to deal with normal spoilage encountered on the shelf; they are no match for a large, healthy colony of aggressive yeast.

I think the key is to give the yeast every chance to thrive in an environment which is somewhat sub-optimal: make a good sized starter, aerate well before pitching and add some yeast nutrient. White Labs makes Servomyces, which I have not used myself, but which seems to work well for those who have tried it. Also, be patient and let the fermentation have time to complete.

Now I think of it, it sounds very similar to brewing mead. Honey is a mild preservative, after all.

Answer 5

Why not boil down the mountain dew to reduce it to a thickened state and add it in late in the fermentation (or even afterwards)

Answer 6

First, the Dew taste was gone because without sweetness, MD tastes like unripened grapefruit juice. Any corn syrup in the MD was converted to alcohol, so you did not get any sweetness.

Second, the preservatives, as stated above are going to affect your yeast. That's why the preservatives are ' n there, to keep it from being affected by spoilers, such as yeast.

So, here's what you can do...as stated above, add Everclear to MD. But, I suspect you want a Mountain Dew Brew. So, make it like you did, by the way, adding sugar was a good move if the MD refused to let the yeast convert its syrup. But, after brewing it, mix it with new Dew.

One more thing. If you can get imported Mexican Mountain Dew, use it. It is made with real sugar instead of corn syrup.

Answer 7

To be honest fermenting soda is probably not a good idea. This is because alcohol made from synthetic sugars always comes out weird. Usually it's not even recommended to add sugar to a mixture to produce alcohol, because using any kind of sugar that isn't completely natural just makes the result bad. If you want a alcoholic soda I'd recommend just mixing in some sort of high proof spirit, like vodka or something, rather than trying to ferment the soda itself. Soda flavoring also pretty much 100% comes from the sugar, so when the yeast eats that you're not left with anything, which is why your end result didn't taste anything like Mtn Dew.

Answer 8

Packaged soda contains preservatives intended to prevent microbial activity such as Sodium Benzoate and Phosphoric acid. I would guess this is interfering with the yeast. Also it is quite acidic overall, some google links say PH around 3.3. This would also cause problems with the yeast.

As others are saying just add vodka (you can distil your own if you really want to ferment something and it's legal where you live) to the soda.

Answer 9

Hey mate I've been making beer and mead for a few years now and im starting to get good at it i have essentially successfully done what you are trying to do and i am now replicating the results with other sodas. However i only recommend doin it with sugar free soft drinks. Heres why. The artificial sweetener can't be broken down by the yeast so all you have to do is add enough sugar to add about .040 gravity to the soda which will get it to about 4-5.5% abv and considering its a diet soda it will taste pretty much the same. Don't make it too alcoholic as it will add undesirable flavour and by keeping it at a standed abv range it leaves the yeast strong enough to ferment the priming sugar into CO2 to carbonate it. Try sugar free mountain dew. Hope this helps.

Answer 10

Mix cane sugar and water in proportions to get the abv you desire, ferment like you normally would. Obtain a box of fountain soda syrup, I suggest a local restaurant as a source, mix syrup in after fermentation and carbonate.