Week 13, Tuesday

Chapter 26

Applied and Industrial Microbiology

Food Micobiology

  • Fermentation

    • A process applied to food and beverage

    • Relies on starter cultures

    • Know the examples used of each

      • I.e. bread, alcohol, dairy products, etc

      • Study the Chart

  • Spoilage

    • Unwanted change to a food that occurs From undesirably metabolic reactions, the growth of pathogens, or the presence of unwanted microorganisms

    • Intrinsic and Extrinsic factors causing spoilage

      • Intrinsic

        • Nutritional composition

        • Water activity

        • pH

        • Physical structure

        • Microbial competition

      • Extrinsic

        • Degree of processing

        • Amount of preservatives

        • Storage temperatures

        • Storage packaging

      • Study the chart

    • Food spoilage categories

      • Perishable

        • Within DAYS

      • Semiperishable

        • Within WEEKS

      • Nonperishable

        • Stored almost indefinitely without spoilage

    • Areas we see spoilage occur

      • During production

      • Processing

        • Pasteurization

      • Packaging

        • Canning

        • aseptic packaging

      • Handling

    • Study the Foodborne Illness chart

Industrial Fermentation:

  • 2 types:

    • Batch production

    • Continuous flow production

Industrial Products

  • Additives

    • Primary metabolites

    • Secondary metabolites

Biosensor and Bioreporters

Water contamination:

  • the presence of anything in the water

Water pollution:

  • something added to water by human activity beyond the capacity of natural processes to get rid of it

Water treatment:

  • Removes most waterborne pathogens

  • Does not completely remove pathogens

    • Everything has an acceptable level in which it can be present in the water

  • Potable water:

    • After that is considered safe to drink, it the term does not imply that the water is devoid of all microorganisms and chemicals

  • Permissible level

    • Varies by state

    • EPA regulated

  • Drinking water treatment:

  • coagulation and flocculation

    • Holding tanks

    • First step

    • Floc= the aggregates in the tank

  • Sedimentation

    • The floc settles to the bottom of the tank

    • Second step

  • Filtration

    • The number of microbes is reduced by 90% in one of several ways

    • Can use sand or other materials

      • Slow sand filters

      • Rapid sand filters

      • Membrane filtration

      • Activated charcoal

  • Disinfection

    • Disinfectants such as ozone, UV light, chlorine or chloramine to kill most microbes

Water Testing:

  • several methods

    • Membrane filtration

      • This method gives a total Coliform count

    • Samples added to bottles containing ONPG MUG as sole nutrients

    • Rapid detection of Coliforms

    • Genetic “fingerprinting” techniques

Waste Water Treatment:

  • sewage or wastewater

    • Everything collected as runoff water

  • Primary Method

    • Reducing biochemical oxygen demands (BOD)

Municipal water treatment

  • 4 phases:

    • primary treatment

      • Removes 25-35% of the BOD in the water

    • Secondary treatment

      • Depends on primary

      • Typically reduces BOD to 5-25% of the original

    • Chemical treatment

      • Only if primary and secondary not successful

    • Sludge treatment

Non-municipal Water treatment

  • used in septic tanks

  • Cesspools are similar to septic tanks

Agricultural waste

  • use Oxidation Lagoons

  • Requires primary and secondary treatment

Wetlands:

  • first pond and second ponds

  • Holds water for a period of time