microbiology 2

• What is one use of bacteria in food production?

  Cheese production
• How does lactic acid bacteria contribute to cheese-making?

  It converts lactose into lactic acid, changing the flavor of the milk
• What is one use of fungi in food production?

  Mycoprotein production
• What is the role of Fusarium bulgaricus in food production?

  It is grown in a fermenter to produce mycoprotein for vegetarian products
• What are the five conditions required for the growth of moulds?

  Time, temperature, oxygen, food, moisture
• What is the optimum temperature range for most moulds?

  Between 20 and 45 degrees Celsius
• How does freezing affect mould growth?

  It inactivates mould growth
• Why do moulds require moisture for growth?

  They grow best in moist, humid conditions
• What type of micro-organisms are aerobic and where do they grow?

  Moulds grow on the surface of solid foods
• What is the reproduction method of moulds?

  Moulds reproduce both asexually and sexually
• What is the name of the bacteria associated with food poisoning discussed in the material?

  Salmonella
• What conditions are necessary for the growth of Salmonella?

  Time, warmth, oxygen, food, and moisture
• What is the doubling time of bacteria like Salmonella under ideal conditions?

  Every 20 minutes
• What temperature range do mesophilic bacteria like Salmonella thrive in?

  Between 20 and 45 degrees Celsius
• What happens to bacteria at temperatures above 75 degrees Celsius?

  Most bacteria are destroyed
• What type of foods are ideal for bacterial growth?

  Moist foods like milk, fish, and stews
• What are the uses of micro-organisms in food production?

  • Bacteria:
  • Cheese: Lactic acid bacteria convert lactose to lactic acid.
  • Yogurt: Lactobacillus bulgaricus ferments milk.
  • Fungi:
  • Mycoprotein: Fusarium bulgaricus is used for vegetarian products.
  • Yeast: Used to ferment alcohol into vinegar.
• What is the temperature range for psychrophiles?

  • 5 to 20 degrees Celsius
• What is the temperature range for thermophiles?

  45 to 75 degrees Celsius
• What is the role of mycelium in mould reproduction?

  It supports the growth of hyphae that produce spores
• What are the two forms of spore structures in moulds?

  Sporangium and conidium
• What happens when a sporangium bursts?

  It releases spores into the atmosphere
• What is the significance of suitable conditions for spores?

  They initiate new mould growth
• What are the characteristics of the mould Rizopus?

  • Saprophytic mould
  • Reproduces asexually
  • Fluffy white mycelium/hyphae
  • Black pinhead sporangia
• What is the temperature range for mould growth?

  Between 20 and 45 degrees Celsius
• What is the effect of cooking temperatures above 75 degrees Celsius on moulds?

  They destroy moulds
• What types of foods do moulds typically feed on?

  Bread, fruit, jam, and cheese
• What is the role of moisture in mould growth?

  Moulds require moisture in liquid form for growth
• What is the significance of the time factor in mould growth?

  Moulds require 24-48 hours to multiply
• What is the importance of oxygen for moulds?

  Moulds are aerobic and grow on the surface of solid foods
• What is the role of saprophytic bacteria in food?

  They cause decomposition in soil and food
• What is the role of parasitic bacteria?

  They cause diseases in humans, plants, and animals
• What is the significance of the temperature range for psychrophiles?

  They thrive in cold environments
• What is the significance of the temperature range for thermophiles?

  They thrive in hot environments
• What is the significance of the temperature range for mesophiles?

  They thrive in moderate temperatures
• What is the role of Lactobacillus bulgaricus in yogurt production?

  It ferments milk, converting lactose to lactic acid
• What is the role of yeast in bread production?

  It ferments sugars to produce carbon dioxide, causing the dough to rise
• What is the role of acetic acid in vinegar production?

  It is produced by the fermentation of alcohol by yeast and bacteria
• What is the significance of the fermentation process in food production?

  It enhances flavor and preserves food
• What is the role of mycelium in mould growth?

  It absorbs nutrients and supports the structure of the mould