yeast fermentation

Most livings undergo the cellular respiration process to obtain and create chemical energy known as adenosine triphosphate. This energy is amalgamated to in a triad of cellular respiration stages namely, electron chain of transportation, glycolysis and the cycle of citric acid. Since they do not require oxygen in the formulation of energy, glycolysis and citric acid are recognized as anaerobic pathways. On the other hand, the electron chain of transportation is aerobic because of its application of oxidative phosphorylation, a process by where ATP molecules are formulated with thanks to molecules of oxygen (Campbell, et al., 2008).

The fermentation process is applied by anaerobic entities to procure ATP without the application of oxygen. The rate of fermentation is affected by sugars. Sugar speeds up the fermentation process. However, different sugars have different effects on the rate of fermentation in yeast; some sugars cause a higher degree of fermentation than others.To determine the legibility of the statement made above, an experiment will be conducted to evaluate the different levels of fermentation in two different yeast solutions. The first yeast solution consists of 5% honey while the second solution contains 20% glucose. The hypothesis behind the experiment is the honey solution will produce more carbon dioxide.

Materials and Methods

To carry out this experiment, the following lab equipment will be required: two fermentation tubes, 2 beakers, an incubator, a digital balance, 20% glucose, 5% honey, 5% glucose, and 3g of yeast. To begin the fermentation exercise, the appropriate amount of yeast to be added to each fermentation tube will be measured using the digital balance.Once the appropriate amount of yeast has been measured, it will be transferred to each beaker to mix it with the appropriate solution, and allowed to incubate at room temperature for five minutes. At the end of the incubation period, the yeast solution will be transferred to the fermentation tubes. The fermentation tubes will then be put in the incubator. The solutions will be left to incubate for 16 minutes checking the amount of carbon dioxide after every 2-minute interval. The amount of carbon dioxide for the two solutions will be recorded between the intervals of 2, 4, 6, 8, 10, 12, 14, and 16 minutes. The results will be tabulated and graphed to observe the trends in the production of carbon dioxide between the two solutions.

Results

Table 1. Amount of Carbon dioxide produced by the two solutions in 2 minutes intervals for 16 minutes.

Graph 1: The amount of carbon dioxide produced by glucose and honey solutions.

According to the experiment, the results demonstrated the following: in the initial two minutes, both solutions produced 0 amounts of carbon dioxide. However, in the fourth minute, the honey solution produced 1ml of carbon dioxide while the glucose solution produced no carbon dioxide. Between the 6^th and 10^th minutes, the amount of carbon dioxide produced by the honey solution underwent a gradual increase but later on dropped in the 12^th minute. In the 14^th and 16^th minute however, it rose a little volume. For the glucose solution, the amount of carbon dioxide was stagnant between the 6^th and 10^th minutes. However, the amount of carbon dioxide gradually rose between the 12^th and 16^th minutes.

Discussion

According to the results from the experiment, carbon dioxide produced by the honey solution exceeded the amount produced by the glucose solution. Although the amount of carbon dioxide produced by the honey solution decreased significantly from the 12^th minute to the 16^th minute, the overall amount of carbon dioxide produced by the honey solution in the course of the experiment surpassed the amount produced by the glucose solution. The honey solution produced 23.8 mL of carbon dioxide while the glucose solution produced 12 mL after 16 minutes of incubation.

As demonstrated by the amount of carbon dioxide produced by the two solutions, it is evident that honey has a significantly higher effect on the rate of fermentation in yeast than glucose. The main goal of the experiment was to understand the fermentation process by yeast. The experiment incorporated glucose and honey. Each fermentation tube had a different solution where one tube had a glucose solution and the other contained a honey solution. It had been predicted that the honey solution would ferment faster and more than the glucose solution hence produces more carbon dioxide. As seen in Graph 1, the prediction was true. After the results were analyzed and graphed, it was concluded that the honey solution produced more carbon dioxide than the glucose.

References

Campbell, N., Reece, J., Urry, L., Cain, M., Wasserman, S., Minorsky, P., Jackson, R.,

(2008) Biology. 8th ed. Pearson Education, San Francisco.

Mark Garcia (n.d). “Lab Protocol-Fermentation in Yeast (Unit 9 Respiration).” Retrieved from https://youtu.be/uN9POjK_iBE Retrieved on 14 October 2019.