Gymnasium Felisenum, The Netherlands
Yeast can metabolize sugar in two ways, aerobically, with the aid of oxygen, or anaerobically, without oxygen.
In this experiment yeast ferment sugars anaerobically. When yeast ferments the sugars anaerobically, however, CO2 production will cause a change in the weight of the sugar/yeast-solution. This raises a further question: What is the effect of different kinds of sugars on the fermentation process of yeast? The fermentation process was followed at a constant temperature and four different types of sugars were used. By measuring the release of carbon dioxide, we could see what type of sugar had the biggest effect on the fermentation process of yeast, which resulted in Sacharose.
Fermentation, sugars, yeast, carbon dioxide mass measurements
Yeast are able to metabolize some foods, but not others. In order for an organism to make use of a potential source of food, it must be capable of transporting the food into its cells. It must also have the proper enzymes capable of breaking the food’s chemical bonds in a useful way. Sugars are vital to all living organisms. Yeast are capable of using some, but not all sugars as a food source. Yeasts reproduce rapidly through fission or budding and grow especially well in substances containing sugar.
Baker 's yeast enzymes convert sugar to ethanol and carbon dioxide. Baker 's yeast is cultivated from the strain Saccharomyces cerevisiae because of its superior fermentation abilities. The yeast propagates in pure culture using special culture media comprised of melasse and other ingredients. With respect to their metabolism baker ' yeasts are facultative anaerobe. They can ferment or respire depending upon environmental conditions. In the presence of oxygen respiration takes place, without oxygen present, fermentation occurs. Fermentation is a process by which a living cell, such as
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