The Netherlands 14-04-2010 Summary 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 Introduction 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.
The Essay on Yeast Fermentation Lab Report
Introduction: Fermentation is a metabolic pathway that produce ATP molecules under anaerobic conditions (only undergoes glycolysis), NAD+ is used directly in glycolysis to form ATP molecules, which is not as efficient as cellular respiration because only 2ATP molecules are formed during the glycolysis. One type of fermentation is alcohol fermentation, it produces pyruvate molecules made by ...
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 yeast, obtains energy through the breakdown of glucose and other simple sugars. [pic] In this experiment four types of sugars are used: Sucrose, Lactose, Fructose and Dextrose(Glucose).
A disaccharide is the carbohydrate formed when two monosaccharides undergo a condensation reaction which involves the elimination of a small molecule, such as water, from the functional groups only.
For example: milk sugar (lactose) is made from glucose and galactose whereas cane sugar (sucrose) is made from glucose and fructose. The two monosaccharides are bonded via a dehydration reaction (also called a condensation reaction or dehydration synthesis) that leads to the loss of a molecule of water and formation of a glycosidic bond. The glycosidic bond can be formed between any hydroxyl group on the component monosaccharide. So, even if both component sugars are the same (e. g. , glucose), different bond combinations and stereochemistry result in disaccharides that are diastereoisomers with different chemical and physical properties.
Dissacharide (sucrose) [pic] Monosacharide (fructose) [pic] All this together raises the question: What is the effect of different kinds of sugars on the fermentation process of yeast? My hypothesis is that fructose and dextrose will produce the most CO2, because sucrose is a combination of two glucose molecules(disaccharide).
Sucrose has to be further metabolized/digested to break it down into glucose molecules. The yeast already fed glucose/fructose does not have to do this, because these are monosaccharide’s.
Therefore it ferments faster. Experimental procedure and approach First I weighted 8 portions of 1 gram of baker’s yeast. Then 45 grams of sugar: 45 grams of sucrose, 45 grams of lactose etc. Eight bottles were labeled, each with one type of sugar. There were two bottles for every type of sugar, this according to the accuracy of the experiment. Every empty bottle was filled with 250 ml of water, then marked at which point the water came and was made empty again. To each bottle was now 45 grams of sugar, each two bottles a different type.
The Term Paper on Affect of Sugars on Yeast Respiration
In this investigation, the rate of carbon dioxide production (cellular respiration) of yeast using different sugars and one artificial sugar will be measured. The natural sugars used in this investigation will be sucrose (table sugar) and lactose (in milk). The artificial sugar that will be used is aspartame (equal). The rate of respiration between the natural sugars will be compared to that of ...
Conclusion and Discussion In this experiment sucrose seems to have the highest CO2 production. I am especially curious about why glucose didn’t make the yeast produced the most CO2. Basically, each sugar needs to be converted to glucose to enable it to feed into respiration and it is this process which produces the gas. Yeast is able to synthesise a range of enzymes to do this:- Sucrose is a disaccharide: Sucrose = Glucose + Fructose Sucrase will split the sucrose molecule. Isomerase will convert Fructose to Glucose. So it could be possible that baker’s yeast have that isomerase enzyme. Thus, 0. 1M sucrose will yield 0. 2M glucose (when all is converted to glucose).
So, I suspect sucrose came out best because it yielded twice as much glucose as the “same concentration” of glucose. It was also conspicious that lactose did not produced any CO2 at all. Lactose is a disaccharide: Lactose = Glucose + Galactose. Lactase will split lactose and Transacetylase will convert Galactose to Glucose. However, yeast does not have the gene for lactase and this is why the lactose sugar remains intact. Looking critically at this experimental procedure, the control variables should be measured better. It could be possible that one bottle stood a little more in the sun than the other, so this could possibly effect the results of this experiment.
