Root Beer of course! And no fancy forced carbonation equipment is needed. But first, an explanation of sorts is needed on the ingredient list.
I have come to find that Sassafras is illegal to sell in the United States. The main ingredient in Sassafras oil is Safrole - a chemical that has been determined to be mildly carcinogenic by the Food and Drug Administration. Bugger.
Safrole can be removed from Sassafras root oils - but it requires specialized equipment and stringent processing. Not something the average home soda maker can do. The alternative is, processed concentrate :P
Yes, by entering this - I am saying you could win my heart with a bottle of root beer (or even better, home made ginger ale).
Step 1: Ingredients and Materials
1 Cup Cane Sugar
1/4 teaspoon Yeast
1 tablespoon Root Beer Concentrate
Fill your bottle half way and then add about a quarter cup of chlorine bleach. Then fill the bottle with water to the top. Cap and allow to rest on its side for about fifteen minutes. Afterwards, rinse well.
Step 2: Add Ingredients
1. Add Sugar
2. Add Yeast and mix evenly
3. Add 1 Tablespoon of Root Beer Concentrate
4. Fill bottle halfway with cool water and rinse measuring spoon/funnel (concentrate is sticky)
Now cap the bottle and shake well
5. Fill the remaining space in the bottle with water.
Cap again and shake again.
Step 3: Carbonation
At least two times a day, check the pressure in the bottle. Give the side of the plastic bottle a hard squeeze with your thumb. When the bottle is done, you won't be able to make a dent. At this point immediatly move the bottle to your refrigerator. Otherwise, you risk blowing your bottles creating a sticky icky mess.
You'll notice that after 10 minutes or so, the process has already started :D
After the drink has been refrigerated - serve and drink within a week. You can filter out the leftover yeast, but this is not necessary (just leave it at the bottom of your bottles).
Step 4: A Word about Alcohol
The Anaerobic process is also known as fermentation. During strenuous usage of muscles, your tissues generate energy (quickly) using anaerobically - the by product being that ever so nasty Lactic acid. Our yeast won't be running any marathons, but it will be generating energy anaerobically. Instead of lactic acid, it will be making ethanol.
Not to worry though, ethanol production will be less than .5% by volume - that is, less than 1 proof. A healthy human body can process ethanol at a rate of about 1oz. per hour. This 2l bottle contains 1/3 of an ounce of ethanol (if we assume the maximum case scenario for alcohol production). So, if you were to drink the whole 2l bottle in a few minutes and IF we assume you absorbed all .3oz of alcohol, the alcohol would be out of your system in about 20 minutes after absorption (which can take 20 minutes).
So for a 12oz. ale (typically 6% alcohol by volume) - you need to drink almost 1.5 gallons of this home made drink rather quickly. For that matter, you probably should not be drinking that much - someone recently died from such stupid acts.
Now, if drinking alcohol is against your devout beliefs (Islam, Orthodox Judaism, Buddhism etc.) - you may want to avoid making this drink. However, I will have an "instant root beer" recipe soon. It just requires some fine tuning.
Similarly, if you are extremely sensitive to alcohol. You probably should avoid.
Of course, I am overstating any risk here ;)
Contrary to a comment -- this is not a Rum. There are many ratings/standards (typically age and/or proof) for what makes rum -- this varies country to country. By the most lax definition, this comes nowhere near rum. Hell, it's not even distilled. Not to mention, when was the last time you had a carbonated rum?
This almost (by technicality) is not a beer. But because there is a fermentation process (which happens while it is carbonating), it meets criteria. I guess you could call it a water beer (as was consumed ages ago due to low quality water). The "instant root beer" recipe, by technicality, is not a "beer" -- just flavored ;)