Instructions: Laura E. Quarantiello, author of The Root Beer Book: A celebration of Americas favorite soft drink (LimeLight Books, $14.95) suggests that people start by making one gallon of root beer, just to get the hang of things. Begin by: Thoroughly cleaning a one-liter plastic or glass container with hot water and soap. Pay special attention to the little nooks and crannies at the bottom of the bottles. Any odd fungal growth may be dangerous to your health as well as imparting a nasty taste to your root beer.

Add 1/8 to 1/4 tablespoon of yeast to one cup of warm water (lukewarm to touch, not hot, not cold) and let stand for five minutes. This is the most critical part of the entire process, as the yeast must dissolve completely. If, after five minutes or more, the yeast is not dissolved, throw away the mixture, break open another packet and try again.

Next, combine one tablespoon of root beer extract and two cups of sugar in a bowl of warm water. How much water? Enough to dissolve the sugar in. Stir it well until the sugar has dissolved, then add the yeast mixture.

To this add enough warm water to bring the entire mixture to the one gallon level. Its best to use a one gallon bowl, otherwise youll end up estimating quantities.

Fill your liter bottle to within one inch of the top and twist on the cap tightly. If you measured incorrectly and have more mixture left over, just use another bottle. Remember that the cap should be sealed tightly to ensure good carbonation.

Set the bottles aside for three to four days at room temperature. Dont put them in the sun, next to the stove or microwave, or near the refrigerator.

After three or four days, move the bottles to a cool dark place (a cabinet works fine) and allow them to stand for one to two weeks.

The yeast needs time to do its thing, and some yeast takes longer than others, so the actual brewing time may vary. It is critical that you check the bottles daily by gently squeezing them. When they are firm, theyre ready. If you use glass bottles, the degree of carbonation is harder to check; youll need to crack the top and check for the sound of escaping air. In this respect, plastic bottles are easier to monitor.

Once the bottles are firm to the touch, carbonation is complete. Refrigerate the bottles to stop the process. It is possible for fermenting bottles to explode or otherwise overflow if the fermenting process is allowed to continue too long or the caps are not applied tightly. For this reason, check them daily.

After fermentation it is quite normal to find a layer of yeast taking up residence at the bottom of the bottles. These yeastie beasties have worked hard at carbonating the root beer. Just pour carefully and the deposits should remain on the bottom. When the bottle is empty, be sure to rinse out the bottom well, using a bottle brush if necessary to clean it completely. You can also decant the liquid into another container, then reseal and refrigerate.

Thats the procedure in a nut shell. There are almost infinite variations, but this is the easiest and seems to work the best, especially for beginners. An even simpler version makes about two to six cups of non-carbonated root beer. Use 1/4 tablespoon of root beer extract to 12 ounces of water, and stir in two tablespoons of sugar or other sweetener. It tastes just as good, but youll miss the fizz.

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