Fermentation Requirements of Yeast.Discuss

Fermentation Requirements of Yeast
Marya Al Nasser
Partner…
2180-013
February 25,2016
Professors: John Arnold; Brenda Leady

Abstract:
There are such different forms of food that we eat every day, and for each type there is different way to digest it. In the digestion, there are a lot of reactions happen so we have reactants and products. For example, the carbohydrate digestion can release energy and it is a potential energy. These reactions occur in the cytoplasm or in the mitochondria. One of the most popular carbohydrates is the glucose. Also it cab with the present of Oxygen which it called aerobic respiration, or with the absent of Oxygen which is called anaerobic respiration. When we have yeast and carbohydrates the products will be ATP and CO2? And can CO2 will be always a product? Also, can the yeast react with all types of carbohydrates?

Hypothesis:
How can the types of carbohydrate like glucose, sucrose, starch, fructose, and saccharine can affect the amount of fermentation? Why?

Methods:
In this experiments we used:
Take six test tubes and label them (glucose, fructose, sucrose, starch, saccharine, and control).
Fill 5 flasks with warm water bath, and stand each tube in a flask.
Attach tow pipettes with each other by a rubber and transfer yeast to each test tube after fill the pipette to the zero.
Record the initial volume for each test tube.
Record the volume for each test tube every tow minutes for 30 minutes.
Record the change in volume at 2 minutes.
In the end of the experiment rinse and watch all the test tubes and flasks.
Results:
This experiment shows how the yeasts react with carbohydrates to produce CO2 and ATP. We can notice from the results in table 1 how the yeast react with different types of carbohydrate while do not react with starch. We can get from this result how the type and complex the carbohydrates are can affect the amount of CO2 that produced. There is no CO2 produced when yeast react with starch because the starch is a complex carbohydrate so we need an enzyme to speed up the reaction. Also in the control one we did not see any change because there is no carbohydrate in it. For Table 2 we can see the change in producing CO2 every 2 minutes for 30 minutes.

Table 1:
Time (min) Glucose Fructose Sucrose Starch Saccharin Control
2 0.7 0.6 0.2 0 0.2 0
4 0.4 0.4 0.3 0 0.5 0
6 0.3 0.5 0.5 0 0.7 0
8 0.6 0.3 0.7 0 0.8 0
10 0.6 0.6 0.6 0 0.5 0
12 0.8 0.4 0.8 0 0.7 0
14 0.8 0.5 0.8 0 0.8 0
16 0.8 0.5 0.6 0 0.5 0
18 0.8 0.5 0.7 0 0.7 0
20 0.5 0.3 0.6 0 0.6 0
22 0.5 0.3 0.4 0 0.4 0
24 0.3 0.3 0.5 0 0.4 0
26 0.2 0.3 0.3 0 0.4 0
28 0.1 0.3 0.2 0 0.2 0
30 0.1 0.1 0.2 0 0.1 0
Avg 0.5 0.393333333 0.493333333 0 0.5 0
StDev 0.247655675 0.133998342 0.20805982 0 0.212916259 0

Table 2:
Time (min) Glucose Fructose Sucrose Starch Saccharin Control
0 10 10 9.4 9.7 9.7 10
2 9.3 9.4 9.2 9.7 9.5 10
4 8.9 9 8.9 9.7 9 10
6 8.6 8.5 8.4 9.7 8.3 10
8 8 8.2 7.7 9.7 7.5 10
10 7.4 7.6 7.1 9.7 7 10
12 6.6 7.2 6.3 9.7 6.3 10
14 5.8 6.7 5.5 9.7 5.5 10
16 5 6.2 4.9 9.7 5 10
18 4.2 5.7 4.2 9.7 4.3 10
20 3.7 5.4 3.6 9.7 3.7 10
22 3.2 5.1 3.2 9.7 3.3 10
24 2.9 4.8 2.7 9.7 2.9 10
26 2.7 4.5 2.4 9.7 2.5 10
28 2.6 4.4 2.2 9.7 2.3 10
30 2.5 4.3 2 9.7 2.1 10

Graph 1:

Conclusion:
We have in this experiments five types of carbohydrates, they are Glucose C6H12O6, Fructose C6H12O6, Sucrose C12H22O11, starch C6H10O5, and saccharine C7H5NO3S. For this experiment the type of carbohydrate plays a role in the fermentation. Thus, we can see the different between the results in graph 1. This graph shows us how the more simple carbohydrate the more fermentation happen. For the more complex carbohydrate, which is, the starch there is no reaction happens because it is too hard to break down by yeast, and for this type of carbohydrate we need catalysts such as enzymes. The data that I have in table 1 and graph 1 really supports my hypothesis. For the control test tubes there is nothing changes because there is no carbohydrate in it. The yeast could produce gas with water only if the yeast are alive. It is important to have a control test tube in the experiment so you can see the reactions that could happen for each test tube. There are some weaknesses in the experimental design. For example, when we attach tow pipettes with each other by using rubber, instead of all of this we can replace it with longer pipette so we can use one pipette instead of two. There are lots of mistakes could happen in this experiments, for me I don’t really know how to use the pipette to transfer the carbohydrates to the test tubes, the pipettes really confused me. Also, some of the test tubes are so dirty and the dirt sis not go even though I rinsed them several times and I used the test tube brush. Moreover, for the time that we need to watch and record for every tow minutes, it is impossible to record the exact number for the 6 pipettes in the same time. I think recording the time could affect my results.