Prescott's Microbiology
11th Edition
ISBN: 9781260211887
Author: WILLEY, Sandman, Wood
Publisher: McGraw Hill
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Chapter 41, Problem 4AL
During cheese production, LAB convert lactose to lactate and casein (milk protein) to amino acids. Lactate and amino acids then become the substrates for further microbial growth, which results in aroma production and deacidification of the cheese. The yeast Yarrowia lipolytica grows on the surface of many cheeses; it is capable of both lactate and amino acid catabolism. When grown on a lactate plus amino acid medium, Y. lipolytica preferentially consumes amino acids. Amino acid degradation results in the release of ammonia, which increases the pH. Draw a flow chart that shows the LAB fermentation of milk, followed by the growth of Y. lipolytica. Indicate which substrates are consumed first and what happens to the pH. Based on this simplified scenario, why do you think most cheeses involve the activity of more than one yeast species?
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Chapter 41 Solutions
Prescott's Microbiology
Ch. 41.1 - What are some intrinsic factors that influence...Ch. 41.1 - How would the spoilage of bread differ from that...Ch. 41.1 - Why do sausage and other ground meat products...Ch. 41.1 - What extrinsic factors can determine whether food...Ch. 41.2 - MICRO INQUIRY Canned products such as vegetable...Ch. 41.2 - Prob. 1CCCh. 41.2 - What types of chemicals can be used to preserve...Ch. 41.2 - What cellular component does HHP target? What is...Ch. 41.2 - How does nisin function? What bacterial genus...Ch. 41.2 - Prob. 5CC
Ch. 41.2 - What are the major gases involved in MAP? How are...Ch. 41.3 - MICRO INQUIRY What foods are most prone to...Ch. 41.3 - What is the difference between a food-borne...Ch. 41.3 - What practical recommendations regarding food...Ch. 41.3 - Prob. 3CCCh. 41.3 - Members of what microbial genus produce fumonisins...Ch. 41.4 - MICRO INQUIRY Why is it important that PulseNet...Ch. 41.4 - Prob. 1CCCh. 41.4 - Prob. 2CCCh. 41.4 - Prob. 3CCCh. 41.5 - Can you name at least two features that make these...Ch. 41.5 - What are the major types of milk fermentations?Ch. 41.5 - What are the major types of milk fermentations?Ch. 41.5 - What major steps are used to produce cheese? How...Ch. 41.5 - Prob. 4CCCh. 41.5 - Describe and contrast the processes of wine and...Ch. 41.5 - Prob. 6CCCh. 41 - Prob. 1RCCh. 41 - Prob. 2RCCh. 41 - Prob. 3RCCh. 41 - Prob. 4RCCh. 41 - Prob. 5RCCh. 41 - Prob. 6RCCh. 41 - Prob. 7RCCh. 41 - Compare the sell-by date of a package of hot dogs...Ch. 41 - You are going through a salad line in a cafeteria...Ch. 41 - Keep a record of what you eat for a day or two....Ch. 41 - During cheese production, LAB convert lactose to...Ch. 41 - Prob. 5AL
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