Study Guide for my Fermentation class. Please help me be sure and study the corr
ID: 56718 • Letter: S
Question
Study Guide for my Fermentation class. Please help me be sure and study the correct things for my midterm.
Define what fermentation is, discuss the history of the processes, and explain why we should care to study fermentation?
A bacterium is known to produce only Lactic Acid. Name the group of bacteria it belongs to, and outline the process that converts Glucose to Lactic acid, naming any major intermediate products and alternate products along the way.
What is/are the difference(s) between traditional culture starters and starters used for mass production? What are the advantages and disadvantages of both?
What is the difference between homolactic and heterolactic fermentation? How are these processes similar? Give examples of different ferments which utilize each pathway.
Humans and microbes have evolved symbiotically over time through a process known as symbiogenesis. Bacterial fermentation to produce foods is included in this symbiotic evolution, but only recently. More than the majority of this symbiogenesis is a result of interactions between microbes and the human body. Give specific examples of symbiotic relationships between microbes and our bodies and the benefits of these relationships. Why are bacteria such effective coevolutionary partners?
Explain/examine the cultural significance of 3 of the fermented products we have studied thus far.
In which ways is fermentation similar and different in other cultures when compared to fermentation practices utilized in the United States today? Explain and discuss 3 examples.
Your task is to write a complete set of instructions for a beginner with no equipment or knowledge of fermentation, describe a basic recipe and explan the tools you would need and the information you must know in order to complete the simple ferment. Tell why each tool or ingredient is used, provide a step by step guide to your ferment, and reasoning behind why you decided to do what you did.
In American health today, we have a rise of the use of medications that cause the death of natural gut bacteria; this has led to many health problems. Rises in leaky gut syndrome all the way to mental illnesses that could be linked to the insufficient presence of healthy gut bacteria. Discuss this issue in more depth and explain how fermentation may be a solution.
Explanation / Answer
1. The conversion of carbohydrates (glucose, sucrose, maltose, starch etc) into alcohol (ethyl alcohol, propyl alcohol and butyl alcohol etc) or organic acids (acetic acis, lactic acids, succinic acid, maleic acid, fumaric acid etc) in absence of oxygen is known as fermentation.
In this process the glucose is broken down by glycolysis like that of in aerobic respiration. But, the end product of glycolysis pyruvate is converted to either alcohol or organic acid (citric acid cycle intermediate through alternative process).
Since, ATP produced during glycolysis are only 2 and no further generation of ATP, fermentation is not much efficient as aerobic respiration.
2. Louis pasteur first studied about the fermentation of grape juice into wine by Sacharomyces cerevisiae. We should care and study about fermentation to have important knowledge regarding various fermented food products we consume such as bread, wine, vinegar, cheese, sauerkraut, dairy products, various types of alcohols and many such other food products.
3. Lactic acid producing bacteria are called as Lactobacilli and they belong lactic acid bacteria group. L. acidophilus, L. rhamnosus, L. plantarum and various other species are used as starters to produce various kinds of fermented products. The end product of glycolysis, the pyruvate is conveted to lactate by lactate dehydrogenase enzyme.
Alternatively, pyruvate is decaroxylated to acetaldehyde by pyruvate decarboxylase enzyme and the acetaldehyde produced is converted to ethanol by alcohol dehydrogenase.
4. Traditional starter cultures are the cultures used for the production of a fermented product in samll scale. Their efficiency to produce that specific product would be minimum but they are used to culture small number of organisms initially and further these traditional cultures can be used for mass production. In mass production culture large quantities of cultures are produced in a large scale to produce the fermented product in high quantities. Traditional cultures require less precautionary measures and monitoring while, the mass cultures sholud be monitored regularly. The conditions for mass cultures are striclty maintained. Contamination should be strictly avoided, otherwise it would affect the quality of final product. The temperature, aeration, agitation and nutrient supply are regularly monitored to obtain the end product in desired quantities.
5. If only two molecules of lactate are produced , then the process is called homolactate fermentation. If other products like ethnol and CO2 are produced along with lactate then, the process is called heterolactic fermentation and is carried out by phosphoketolase pathway.