Baker's yeast and vinter's yeast are very similar, however a few additional ingredients and steps are needed for baker's yeast to properly produce alcohol. Baker's yeast will always have a lower attenuation, or alcohol level, than vinter's yeast simply because of its contents; however you can make a decent alcohol or wine using baker's yeast if you don't have access to vinter's yeast. A fruit juice is needed to make alcohol with baker's yeast because it contains the necessary nutrients that feed the yeast. Vinter's yeast has these nutrients added to it to. Sucrose, or table sugar, is an excellent food for the yeast to feed on to produce alcohol, which also lends a sweet flavor to your finished product.
Sanitize your tools by putting 1 tbsp. baking soda into the gallon jug and filling the jug with water. Put 1 tbsp. of baking soda and 2 qt. of water into the plastic tub and place the measuring cup, small bowl and funnel into the tub. Allow the jug and the tub to sit overnight.
Thaw the grape juice overnight in the refrigerator.
Empty the jug containing the sanitizing liquid and rinse well with water. Place the funnel into the top of the gallon jug and pour the thawed grape juice concentrate into the jug.
Fill an empty grape juice container with water and pour it into the gallon jug. Repeat this until you have added six juice containers of water.
Put the top on the jug and shake the juice and water well. Bubbles should form on top. This is called "aerating the must," in alcohol making.
Place the funnel into the top of the jug and pour in a 1/2 cup of sugar that has been measured with the sanitized measuring cup. Put the lid on the jug and shake it vigorously until the sugar is mixed in and does not settle to the bottom when left sitting.
Measure 1/4 cup of water into the small bowl and place it in the microwave for about 45 seconds on high to heat up. Add the yeast packet to the heated water and allow it to sit for 15 minutes.
Add 2 tbsp. of sugar to the yeast mixture and allow it to sit for about 10 minutes or until the foam that it forms has doubled the volume of the mixture.
Put the funnel back into the jug, pour the foaming yeast mixture into the jug and shake the jug vigorously for one minute. Quickly put the balloon over the mouth of the jug pulling the excess around the mouth of the jug so that the balloon creates a flat surface over the mouth opening.
Poke five holes into the top of the balloon with the needle to allow gasses to escape. Put the rubber band around the mouth of the jug and balloon to keep the balloon in place.
Allow the jug to sit in a cool dark place for two weeks or until the balloon is no longer releasing gasses. You will know when fermentation has started when gasses begin to release from the balloon and inflate it slightly. You will see this stop when fermentation has complete.