L1 FT 15 LEC - Food Microbiology

• “And now here is my secret, a very simple secret: It is only with the heart that one can see rightly; what is essential is invisible to the eye.”
• “And now here is my secret, a very simple secret: It is only with the heart that one can see rightly; what is essential is invisible to the eye.”


  Antoine de Saint-Exupéry, The LittlePrince
• Anton Van Leeuwenhoek
• • Examined cork samples with a crude microscope (1665)  
  • Cell Theory: all living things are composed of cells
• Spontaneous Generation

  The belief that some forms of life could arise spontaneously from nonliving matter
• Robert Hooke

  • Examined cork samples with a crude microscope (1665)  
  • Cell Theory: all living things are composed of cells
• Disproving Spontaneous Generation

  • Francesco Redi - Demonstrated that maggots didn’t arise spontaneously (1668)
• • Louis Pasteur
  • Demonstrated: microbes are present in nonliving matter—air, liquids, and solids. 
  • Demonstrated:  these microbes caused food spoilage
  • His work is foundational in developing aseptic techniques
• First Golden Age of Microbiology (1857-1911)
• Fermentation (Beer and Wine)

  • Converting sugars into alcohol

  - The old belief: AIR

  - Pasteur’s findings: YEASTS (in the absence of air)

  
  

  • Souring and Spoilege

  -Pasteur’s findings: BACTERIA (in the presence of air)
• Pasteurization

  • HEAT kills the majority of bacteria causing spoilage
  • Modern applications:

        • milk 

        • fruit and vegetable juices

        • alcoholic beverages
• Germ Theory of Disease

  • microorganisms cause disease
• Joseph Lister: 

  -used phenol to perform surgery under aseptic condition

  -Lister proved microbes caused surgical wound infections
• • Robert Koch

  -first to prove that bacteria caused disease

  -Bacillus anthracis: Anthrax

  -Koch’s Postulates

  • for directly relatingaspecificmicrobe to aspecificdisease
• Vaccination 

  • Edward Jenner (1796)

           •  worked on a smallpox vaccine using scrapings from cowpox blisters

           •  Both cowpox and small pox are caused by VIRUSES

           •  Pasteur coined term “vaccine” (Vacca is Latin for cow)
• Multiple Disciplines Under Microbiology (BMPIVM)

  • Bacteriology (Bacteria) 
  • Mycology (Fungi) 
  • Parasitology (Protozoa and parasitic worms) 
  • Immunology (Immunity) 
  • Virology (Viruses)
  • Molecular Genetics
• Impact -RSBIB

  -Recycling Vital Elements

  -SewageTreatment

  - Bioremediation

  - Insect Pest Control

  - Biotechnology
•  Biotechnology

  – practical applications of microbiology in food production or chemical production
• Recycling Vital Elements

  • bacteria recycle vital elements between soil & atmosphere
  • Microbes convert C, N, O, S and P into usable forms for plants & animals
• SewageTreatment

  • bacteria convert liquids &organic materials in wastewater into by-products like CO2, Nitrates, Phosphates, Ammonia, Methane, etc.
• Bioremediation

  • microbes cleaning up pollutants and toxic wastes from industrial processes
• Insect Pest Control

  • Bacillus thuringiensis incorporated into a powder dusted onto crops

         •  worked on a smallpox vaccine using scrapings from cowpox blisters
•  Biotechnology

  – practical applications of microbiology in food production or chemical production