Transport Processes and Separation Process Principles (Includes Unit Operations) Fourth Edition

9.12. UNSTEADY-STATE THERMAL PROCESSING AND STERILIZATION OF BIOLOGICAL MATERIALS

9.12A. Introduction

Materials of biological origin are usually not as stable as most inorganic and some organic materials. Hence, it is necessary to use certain processing methods to preserve biological materials, especially foods. Physical and chemical processing methods of preservation, such as drying, smoking, salting, chilling, freezing, and heating, are commonly used. Freezing and chilling of foods were discussed in Section 5.5 as methods of slowing the spoilage of biological materials. Also, in Section 9.11, freeze-drying of biological materials was discussed.

An important method is heat or thermal processing, whereby contaminating microorganisms that occur ...