The hypothesis is that the UV light will reduce the rate of yeast fermentation, but not eliminate it.

You will fill a water bath with water, fill a measuring cylinder with water, put plastic wrap over the measuring cylinder, flip the water-filled measuring cylinder over in the water bath, put 100ml of apple juice into a flask, heat the apple juice in the microwave, add 1/4 teaspoon of yeast to the flask, shake the flask to mix the apple juice and yeast, plug in a heating pad, put the flask on the heating pad, slide a stopper into the top of the flask, place a rubber tubing into the water bath, slip a plastic tubing up inside the cylinder, put a straw on the other side of the measuring cylinder to balance it, and watch for CO2 bubbles in the measuring cylinder.

You will need a flask, a measuring cylinder, a water bath, a stopper, a clamp and stand, an UV lamp, a teaspoon of yeast, a 100ml plastic tube, apple juice, a microwave, a heating pad, a pencil, and a paper pad.

The results showed that the UV light did affect the fermentation rate of the yeast. The amount of displaced water was about 60 milliliters. The water level went down about 30 ml every ten minutes in both the UV light trial and the control test. However, in the UV light trial, the water level didn't change for the first 20 minutes. The rate of bubbles in the UV light was much slower towards the end of the experiment than the control test.

This science project is interesting because it provides insight into a new way to pasteurize juices.

Variations to consider include using a stronger UV light and doing more trials and averaging the results.