LAB REPORT Essay

Submitted By tylerp00
Words: 770
Pages: 4

ABSTRACT
We were interested in the effects of different glucose substances on the rate of fermentation produced. We hypothesized that the tube with the fructose would have a high rate of fermentation, or gas in the tube, than the tubes with apple juice orand sucrose. Using three fermentation tubes we filled each one with yeast, and water and added apple juice, 5% sucrose or 5% fructose to each tube. Then we monitored the tubes for gas production. After performing the experiment twice we found that the sucrose and apple juice produced the most gas; therefore, producing the most fermentation. The tubes containing the sucrose and apple juice had a high rate of carbon dioxide gas production in the thirty-minute period than that of the fructose.
INTRODUCTION

Alcoholic fermentation, or ethanol fermentation, is a process in which sugars such as glucose, fructose, and sucrose are converted into energy and produce ethanol and carbon dioxide as metabolic waste products. Fermentation reactions reduce pyruvate with electrons from NADH to NAD+ producing ethanol in yeast, and lactic acid in muscle cells when oxygen is absent (Choi, 2012). Because this process occurs in the absence of oxygen, alcoholic fermentation is considered an anaerobic process. Fructose is a monosaccharide found abundantly in nature, it is the sweetest carbohydrate created naturally (Bantle, 2006). Sucrose is composed of fructose and glucose, it has a high concentration of glucans in its matrix and due to its composition of fructose is has a lower glycemic index (Cury, et al.,2000). A typical bottle of apple juice contains atleast twenty-four grams of sugar., which is composed of about 3125 mg of sucrose, 6523 mg of glucose and 14210 mg of fructose .

MATERIALS AND METHODS
We took three small fermentation tubes and added eight milliliters of water and four milliliters of yeast to each tube. Then we added five milliliters of 5% fructose into tube #1, five milliliters of 5% sucrose into tube #2, and five milliliters of apple juice into tube #3. We mixed the tubes to ensure that we got rid of the gas in the tubes to make sure we got accurate results. We then let the tubes out and monitored them for thirty minutes writing down our observations every five minutes. After we completed the experiment we replicated it a second time an averaged our findings from both experiments.
RESULTS
In testing what affects changing the glucose substance would have on the fermentation rate, we found that the sucrose and apple juice resulted in the highest production of carbon dioxide within a thirty-minute period. By adding the same five milliliters of each of the sugars to each tube and replicating the experiment twice the results showed that after thirty-minutes sucrose and apple juice had produced two milliliters of carbon dioxide and the fructose had only produced one milliliter of CO2.

Fig.1 Fermentation rate of different glucose substances in five-minute increments over a thirty-minute period
DISCUSSION
Our experiment consisted of testing three tubes