Food Science and Nutrition 822
Food Proteins

 

 Mike Mangino  327 Parker Hall   292-7769  Mangino.2@osu.edu  


Office Hours: You may make an appointment or just drop in. I will be available after class every day and from 9:00 until 11:00 most days.


Class Time: M, W, F 8:00 114 Parker


Objectives: Students completing 822 should be able to:
1. Describe the forces involved in protein structure and functionality from a thermodynamic viewpoint.
2. Relate protein structure and functionality to environmental conditions and to achievement of the structure of lowest free energy.
3. Describe the properties of the major classes of food proteins and relate these properties to their behavior in food systems.
4. Describe the effects of processing on the structure and function of proteins in food systems.

Web Page: http://class.fst.ohio-state.edu/FST822

 

Lecture Outline

     Topics
     
 1    Introduction and Overview - Discussion of technology used to visualize protein structures.
     
 3    Thermodynamics - introduction to free energy, entropy, enthalpy, chemical potential and activity. Methods of assessment of these quantities and their relevance to protein structures
     
 3    Bonds and Intermolecular Forces - covalent bonds, ionic bonds, ion-dipole interactions, dipole-dipole interactions, hydrogen bonds , induced dipoles, London forces and the hydrophobic affect. The importance of these forces to the structure of proteins.
     
 1    Amino Acids - primary structure, chemical properties of amino acids, amino acid analysis and sequence determination
     
 3   Protein Structure - peptide bonds, Ramachandran plots, secondary structure, a-helix, b-turn, b-structure, "random" coil, tertiary structure, domains
and quaternary structure
     
 1    Protein Folding - free energy considerations, time of folding, short range forces, predictions of protein structure, tertiary structure and short range interactions, folding to attain native structure.
     
 1   Exam 1 (April 28)
     
 2    Protein Denaturation - denaturation, measuring denaturation, causes of denaturation, mechanisms of denaturation by heat, pH extremes, changes in dielectric constant, exposure to interfaces, high ionic strength.
     
 1   Protein hydrophobicity - methods available to estimate the hydrophobicity of proteins.
     
 4    Protein Functionality - general functional properties including flavor, water binding, gelation, fiber formation, emulsions, foaming and extrusion
     
 1.5   Properties of Caseins, alpha, beta, kappa and gamma, and micelles
     
 1.5   Properties of whey proteins: a lactalbumin, s-lactoglobulin, bovine serum albumin, proteose peptone and immune globulins.
     
 1   Exam 2 (May 23)
     
 1   Properties of Whey Protein Concentrates and Isolates
     
 1    Properties of Soy Proteins - types of products, 2S proteins, 7S proteins, 11S proteins, 11Sproteins, methods of isolation and properties.
     
 1.5   Properties of Muscle Proteins - actin, myosin, tropinin, tropomyosin, minor protein, mechanism of muscular contraction as related to protein structure,post-mortem changes in muscle structure as the affect the quality of meat products.
     
 1.5    Nutritional Evaluation of Proteins - PER, chemical score, biological value, net protein utilization slope assay, the effects of processing on protein quality.
     
     Final Exam. Wednesday June 9 7:30 - 9:18

The course will be graded on the basis of three examinations worth 100 points each. The following grading scale will be used:

 Two Exams 100 points each 200
Processing report   50
Final exam   150

 

A 400-375 C+ 319-307
A- 374-360 C 306-293
 B+  359-347 C-  292-280
 B  346-333 D+  279-267
 B-  332-320 D   266-240
     E  Below 240


During the second week of the class, a list of processes commonly used by the food industry will be distributed. Each student will select three (in order of preference) and return them to the instructor no later than the last day of the third week of the quarter. Students who are interested in some aspect of protein chemistry not on the list, may add that item to the list they return.

Each student will be assigned a process and a date for discussion of the process. On the assigned date it will be the student's responsibility to describe the process to the class> The description should include:

1. Time, temperature, pH extremes, etc that the protein will be exposed to
2. The reason the process is being employed
3. The effects the process has on the food system
4. Alternate conditions that can be used to receive the same result.

This presentation should not exceed 10 minutes. The class will then discuss the material presented with the following goals:

1. To explain the physical/chemical effects the process has on the food system as a whole and the food proteins in particular.

2. To relate as far as is possible these effects to the properties of the proteins involved and explain the changes that occur on the basis of thermodynamic principles.

3. To extrapolate these concepts to other procedures not considered in detail.