While performing grandiose illusions with flashy, store-bought props certainly can be impressive, few leave an impression on an audience like a small scale trick that uses household items -- or at least props that appear to be household items -- and can be viewed from a close perspective. This is especially true if the trick at hand is of a Biblical proportion -- and you can't get much more Biblical than changing water to wine. There are several methods of performing this seemingly miraculous trick, all of which have been employed by professional magicians.
The Chemical Method
One method of seemingly manipulating the properties of water, grape juice and wine involves little magical know-how, but it helps if you paid attention in your high school chemistry class. Put five or six drops of sodium hydroxide solution in a clear, empty water glass. Put three or four drops of phenolphthalein solution in a clear, empty wine glass. Put three or four drops of concentrated acid in another clear, empty wine glass and then fill a clear pitcher with water. To perform this trick, pour water from the pitcher into a clean, untreated water glass and drink it to show the audience the water is untainted. Tell the audience you're still thirsty and pour another glass of water -- only this time into the glass that already contains a few drops of sodium hydroxide. After deciding out loud that you need something "stronger," pour the sodium hydroxide water into the wine glass containing phenolphthalein solution. The liquid will immediately turn dark red, which will pass for red wine or grape juice. To turn it into what appears to be white wine, simply pour the contents of the wine glass into the glass that's been prepared with concentrated acid, which will immediately strip the liquid of its colour.
Add Some Flavor to Your Act
A less complicated method of turning water into wine or grape juice requires only a packet of unsweetened powdered drink mix or several drops of food colouring. The advantage this method has over using chemicals is you can drink the converted liquid once the illusion is complete. However, the disadvantage is the transforming ingredient will be visible through a clear glass. To avoid giving away the secret to the trick, the glass can be placed on a tray with an edge or lip that hides its bottom. Being that most adult audiences likely wouldn't buy into the illusion unless the entire glass was visible, this method is probably best reserved for performances before younger crowds.
The most effective way of performing the water-to-wine or water-to-grape juice illusion is to somehow slip an edible colouring agent into the water after you've begun the trick -- but without the audience seeing you do it. One way of accomplishing this is by hollowing out the cork from a wine bottle, filling it with powdered drink mix and plugging the hole with a small piece of cork. Place the prepared cork in your pocket, fill a wine bottle with water and seal it with a regular cork. When you perform the trick, uncork the bottle, put the cork in your pocket and pour a little water into a glass to show the audience the bottle contains water. Tell the audience something to the effect of, "Perhaps the winemaker didn't mix it well enough." Reach into your pocket, pull out the prepared cork, plug the bottle and shake it. The motion should jar loose the cork plug, releasing the powdered drink mix into the water.
Leaving It to the Pros
Of course, the easiest way to turn water into wine or grape juice is by using magic props made and sold specifically for this purpose. The most common is a special pitcher that holds one type of liquid in its reservoir while concealing a second type inside a double wall. Also available are temperature-activated glasses and cups that change colours when filled with liquid and kits that contain all the ingredients for the chemical method described earlier. These speciality items can be ordered from most online magic stores. The disadvantage to going this route is mainly the cost, which will generally be several times higher than assembling the trick yourself.