Bio 110 Yeast Fermentation

               Yeast fermentation of Monosaccharide and Disaccharides

Group: A. Carpenter, A. Numan and R. McKesson

October 27, 2017

Abstract:

Our initial observation is that fermentation of glucose and yeast yields ethanol and carbon dioxide and ATP and this is how all the great beers and wines are produced. The question is if we know that yeast causes fermentation of glucose then it will also cause fermentation in other monosaccharide and disaccharides. My hypothesis is that if yeast can cars fermentation and glucose a simple sugar then it should be able to cause fermentation and complex sugars. The experiment we tested on 6 different sugars and water and a test to cut off from oxygen with an oil seal and we heated it too see what was the rate of fermentation between the simple monosaccharides and the complex disaccharide. After testing these sugar, the results where that the more complex sugar causes faster fermentation rates thin of the simple sugar glucose and yeast didn’t firm in the water.

Introduction:

In a controlled environment, a specified amount of yeast was added to a controlled amount of sugar, water, and oil. It was then placed in an incubator set to 38⁰ for 10 minutes. This experiment is being done to determine if monosaccharides and disaccharide specifically fructose, glucose, lactose, sucrose, or glucose/fructose will have a rate of fermentation and if so at what rate.  Fermentation is one of the two methods by which cells create ATP – main energy source for metabolic functions, converts pyruvate into lactic acid or ethanol and doesn’t need oxygen. Fermentation occurs when yeast, a nucleic acid is combined with, monosaccharides and disaccharides, which has been diffused in water, and oil (added to control for oxygen) in a small glass beaker and compressed with a rubber stopper, connected to the Gas Pressure Sensor, on a heated block set to 38⁰ C, and connected to a Vernier LabPro Logger for measuring the rate of fermentation. The rate of fermentation of fructose is going to higher because it’s more complex sugar then glucose.

Materials and Methods:

Procedure is found on pages 189 to 190 in the BIOL 110 Lab Manual

Result:

Ethanol Fermentation occurred when a yeast in an environment minus oxygen and combined with fructose, glucose, lactose, sucrose, or glucose/fructose. After doing the test, we found fructose is 0.721kPa/sec and glucose is 0.623kPa/sec.

Discussion:

Yeast Fermentation Rates