Courses

Food Engineering II

General

Course Contents

Unit 1: Fluid Mechanics

  • Pumping: Bernoulli’s theorem, typical pump quantities, suction lift and cavitation, criteria for selecting a pump, types of pumps, applications of pumps, principle of operation and efficiency of steam ejectors.
  • Fluidization theory, fluidization applications.

Titles of Laboratory Exercises.

  • Study of fluidization characteristics of gas/solid system.

Unit 2: Mechanical Separations

  • Sieving: Particle size analysis, sieving applications.
  • Filtration: Darcy’s law, relationships between filtration parameters, constant flow filtration, constant pressure filtration, filter media, filtration devices, filtration applications.
  • Sedimentation: Stokes and Newton’s laws and equations, calculation of sedimentation surface, applications of sedimentation.
  • Centrifugation: Centrifugal separation of immiscible liquids, centrifugal clarification, centrifugal sludge removal, centrifugal filtration, centrifugal devices, cyclones, centrifugal applications.
  • Fractionation: Selection criteria for fractionation devices, fractionation devices, energy requirements of fractionation, fractionation applications.

Titles of Laboratory Exercises.

  • Study of Factors Affecting the Performance of a Ball Mill – Determination of Particle Size Distribution of a Granular Food.
  • Study of the operating parameters of a laboratory filter press.
  • Study of the parameters affecting the performance of a laboratory centrifugal disc separator during the separation of two immiscible liquids and a centrifugal disc clarifier.

Unit 3: Mixing and Homogenization

  • Mixing: Mixing of solids, mixing of liquids and slurries, mixing applications.
  • Homogenization – Emulsification: Interfacial tension, emulsifiers, emulsification – homogenization methods and devices, applications of emulsification – homogenization.

Titles of Laboratory Exercises.

  • Energy requirements during stirring/mixing of liquid foods.
  • Homogenization.

Educational Goals

The course aims to achieve the following learning outcomes for students:

  • Acquiring knowledge in the basic engineering principles that govern the physical processes during food processing and in particular liquid transport, mechanical separations (sieving, filtration, sedimentation, and centrifugation), homogenization, fractionation, mixing and fluidization.
  • Recognizing, understanding and interpreting the physical phenomena govern these processes.
  • Mathematically describing and evaluating the contribution of each phenomenon or parameter to the evolution of the process.
  • Cindustrial applications.
  • Acquiring experience in applying the above knowledge and analytical skills to industrial-type processes and machines.

General Skills

  • Analyzing, interpreting and synthesizing empirical data obtained from experimental setups.
  • Searching and analyzing information using information and communication technologies.
  • Promotion of analytical, productive and inductive thinking.
  • Working in an interdisciplinary environment.
  • Autonomous work.
  • Teamwork.
  • Decision making.

Teaching Methods

Face to face:

  • Lectures (theory and exercises) in the classroom.
  • Laboratory exercises in groups in a pilot plant laboratory.

Use of ICT means

  • Lectures with PowerPoint slides using PC and projector.
  • Notes, solved and unsolved problems in electronic format.
  • Posting course material and communicating with students on the Moodle online platform.
  • Use of electronic devices for retrieving and recording experimental data (data logging) in the laboratory.

Teaching Organization

ActivitySemester workload
Lectures162.5
Total162.5

Students Evaluation

Evaluation methods:

  • Compulsory attendance at (at least) 80% of the laboratory exercises.
  • Written final exams in the theoretical part of the course with problem solving and comprehension/judgment questions (70% of the final grade).
  • Final written exams in the laboratory part of the course with multiple choice, short development and problem-solving questions (30% of the final grade).
  • Optional written assignments in laboratory exercises.

The evaluation criteria are presented and analyzed to the students at the beginning of the semester.

Recommended Bibliography

  1. McCabe W., Smith J., Harriott P.: Βασικές Φυσικές Διεργασίες Μηχανικής. Εκδόσεις Τζιόλα, 2003.
  2. Μαρίνου-Κουρή Δ., Παρλιάρου-Τσάμη Ε.: Ασκήσεις Φυσικών Διεργασιών. Εκδόσεις Παπασωτηρίου, 1994.
  3. Καστρινάκη Ε.: Μηχανικές Φυσικές Διεργασίες. Εκδόσεις Τζιόλα, 2004.
  4. Darby R.: Chemical Engineering Fluid Mechanics. Editions Marcel Dekker, 2001.
  5. Earle R.: Unit Operations in Food Processing (http://www.nzifst.org.nz/unitoperations/)

Related Research Journals

  1. Journal of Food Engineering.
  2. Journal of Food Processing & Technology.