Essentials of Thermobacteriology Workshop

September 15, 2011

1:00 – 2:30  Microbiology of Food Processing                                             

A.    General Microbiology

a.       Bacteria, Molds and Yeast

b.       Factors Influencing Bacterial Growth and Death

c.       Bacterial Spores

B.     Microorganisms of Greatest Importance in Food Processing

a.       Pathogenic Microorganisms

b.       Toxin–producing Microorganisms

c.       Spoilage Microorganisms

2:30-2:45     Break

2:45 – 3:45  Lectures
Determining the Heat Resistance of Microorganisms

A.    Selection of the Target Microorganisms

B.     Preparation of Test Microorganisms

a.      Producing, Harvesting and Cleaning (Vegetative & Spores)

b.      Enumeration of Populations

C.     Heating Medium

a.      Phosphate Buffer

b.      Food

c.      Heat in Product (HIP)/Recovery in Product (RIP)

2) Methods of Measuring Heat Resistance

A.      Thermal Death Time Tube

B.      Thermal Death Time Can

C.      Three–Neck Flask

D.      Thermoresistometer

E.      Capillary Tube

F.      Thermal Death Time Retort

3) Enumeration of Microorganisms After Thermal Treatment

3:45-4:30     Laboratory Session

September 16, 2011

8:00 – 9:30  Thermal Resistance Data Interpretation and Calculations 

A.      Survivors Curves

B.      Decimal Reduction Time (The D Value)

C.      Different Methods for Calculating D Values

D.      Nonlinear Survival Curves

E.      Thermal Death Time (TDT) Curve – Construction and Interpretation

9:30-10:15   Exercise

10:15-10:30  Break

10:30–11:00 4) Application of D, z, and F-values  

A.       F-values

B.      The z-value

C.       Log-reductions

D.      Specific Food Types

11:00–Noon 5) Bacteriological Evaluation for Thermal Process      

A.      Inoculating Pack Studies

B.      Count Reduction

C.      Interpreting and Applying D and z values from the
         Literature to Ensure the Safety of Foods

D.      Integrating Current Modeling Packages and Techniques