1.
FST 2201 FOOD CHEMISTRY II
2.
COURSE INSTRUCTOR
Mr. George W. Kulaba [B.Sc. Chemistry; M.Sc. Chemistry; PGDE; PGDCS.]
3.
COURSE TYPE
Core course for Year II B.Sc. Food Science & Technology
4.
COURSE STRUCTURE
Course is 3 credit units (3 CU): 2 lecture hours and 2 practical hours per week for 15 study weeks; [i.e. 30 lecture hours & 30 practical hours equivalent to 45 contact hours].
5.
COURSE DESCRIPTION
Chemical changes resulting from processing: Lipid deterioration, anti-oxidation and flavour reversion, gelation, protein de-naturation, browning. Syrups: solubility and crystallization. Starch in foods: Granules, chemical aspects of pasting behaviour, starch modification. Toxic constituents and anti-nutrients in foods and their elimination.
6.
COURSE OBJECTIVES
At the end of the course, students should be able to:
1. Develop an understanding of how individual food components contribute to the overall quality of foods and discuss the relationship between chemical and physical composition and function of macro- and micro-components in food.
2. Achieve an understanding of the chemical changes that take place with food components during processing and storage.
 Describe physical and chemical changes that food components undergo during processing and storage.
 Recognize reactions and mechanisms important in food chemistry.
3. Design and conduct experiments and interprete data to understand important food chemistry principles i.e. develop skills for experimenting with food systems and to test various approaches for manipulating the chemical and/or functional properties of foods.
 Test the foods using various analyses and compare and contrast how ingredients, processing, storage influence the finished products and explain each test performed in the laboratory as to why, how, and when
 they are used, and for what products.
Acquire technical data and information for inclusion in a laboratory notebook while performing laboratory experimentation; analyze the information by tabulating data, performing calculations and statistical analyses, and presenting graphic interpretation; document laboratory exercises by submitting reports in a standard journal format; develope ability to present written information of a scientific nature combined with the hands-on experiences.
4. Apply basic principles of food chemistry to discuss the effects of processing and storage on food composition, safety and quality.
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Integrate chemistry and biochemistry principles into real-world food science and nutritional problems.
Explain how ingredients, food components, processing, storage, etc. influences the quality, sensory, and physical and chemical parameters of finished food products.
Compare and contrast various food processing operations on the chemical changes of food components as they relate to food quality, nutrient composition and safety.

3. Recommended reading list
1.
Fennema O.R. 1996. Food Chemistry. Marcel Dekker Inc. New York.
2.
Wong, D.W.S. 1989. Mechanism and theory in food chemistry. AVI, New York.
3.
Christen, G.L. and Smith, J.S. 2000. Food Chemistry: Principles and Applications, Science Technology
System, West Sacramento, CA. USA.
4.
DeMan, J.M. 1999. Principles of Food Chemistry. Aspen Publishers, Gaithersburg, MD.
5.
Belitz, H.D., Grosch, W. and Schieberle. 2004. Food Chemistry, 3rd edition, Springer Verlag, Berlin,
Heidelberg
6.
Miller, D. D. 1998. Food Chemistry: A laboratory manual. John Wiley & Sons. Inc.: New York, USA.
7.
Coultate, T. P. 2002. Food - The Chemistry of its Components, 4 th Ed. Royal Society of Chemistry: London.
8.
Charley, H. and Weaver, C. 1998. Foods: A Scientific Approach. 3rd edition, Merrill, Upper Saddle River,
N.J.
9.
Official Methods of Analysis, current ed. A.O.A.C. Association of Official Analytical Chemists, Arlington, VA.
10.
United States Department of Agriculture. 2002. Nutrient Data Laboratory. (online). (www.usda.gov.).
11.
Sikorski, Z. E. 1996. Chemical and Functional Properties of Food Components. Technomic Publishing Co,
(Tech).
12.
C.E. Meloan and Y. Pomeranz. 1973. Food Analysis Laboratory Experiments. AVI Publishing Company,
Westport.
13.
Walstra, P. 2003. Physical Chemistry of Foods . Marcel Dekker Publishing, New York
4. COURSE CONTENT, METHODS OF INSTRUCTION, TOOLS AND EQUIPMENT REQUIRED
TOPIC
1. Overview of chemical changes and alterations in quality and safety attributes of food during handling, and storage processing
2. Lipid deterioration
3. Processing – induced chemical changes in
CONTENT
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Quality and safety attributes of food and possible alterations
Desirable and undesirable changes
Chemical basis: Cause – and – effect relationships
Factors governing the stability of foods during handling, processing and storage.
Chemical interactions among major food constituents.
 Overview of lipid structure
 Hydrolytic rancidity
 Oxidative rancidity
 Autooxidation
 Antioxidation
 Flavour reversion
 Thermal decomposition
 Radiolysis of lipids
 Chemistry of frying
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Overview of protein structure
Stabilizing forces in protein structure
METHOD
Time allocated audio/visuals, group discussions and writing assignments/exerc ises
Experimentation and
(9
Seminar topics
OF
INSTRUCTION /
Interactive lecture, audio/visuals, small and large group directed discussions and writing assignments
(3 hrs).
Interactive lecture, small and large directed hrs);
Laboratory exercises (6 hrs);
Interactive lecture, audio/visuals,
TOOLS
EQUIPMENT
NEEDED power presentation;
Lab equipment, materials chemicals experiments
/
Chalkboard
/White board;
LCD projector and Computer for power presentation point
LCD and Computer for
LCD projector point and for projector and Computer for

proteins
4. Processing–induced changes and reactions involving carbohydrates
(sugars and starch) in foods
 Functions of proteins
 Denaturation
 Denaturing agents
 Possible results of Denaturation
 Gelation
 Protein–stabilized emulsification and foaming
 Alkali degradation
 Heat–induced formation of isopeptides
 Reaction with carbonyl compounds
 Reaction with products from lipid oxidation.
 Photo-oxidation of Proteins
 Nonenzymatic Browning
� Caramelization
� Flavoring caramelization
� Caramel pigments
� Maillard browning
� Why worry about Maillard
browning?
� Maillard browning reaction
variables
� Control of browning
� Practical examples of the effect of
Maillard browning
 Chemical structure of starch and starch granules
 Chemical aspects of granule gelatinization and pasting behaviour.
 Retrogradation and staling
 RVA graphs of different starches
 Factors affecting gelatinization,
retrogradation, and gel formation
 Modified starches
� Waxy
� Pregelatinized
� Acid modified (thin boiling)
� Cross-linked
� Derivatized
 Starch degrading/debranching enzymes
 Syrups: Solubility, Crystallisation, Corn syrup manufacture small and large group directed discussions and writing assignments/exerc ises (6 hrs);
Experimentation and Laboratory exercises (3 hrs);
Seminar topics power point presentation;
Lab equipment, materials and chemicals for experiments
Interactive lecture, audio/visuals, small and large group directed discussions and writing assignments/exerc ises (9 hrs);
Experimentation and Laboratory exercises (3 hrs);
Seminar topics
LCD projector and Computer for power point presentation;
Lab equipment, materials and chemicals for experiments

5. Effects of processing and handling conditions on inherent food colourants
 Definitions: Colour, colourant, hue pigment
 Types of pigments and their food sources
 Meat pigments (myoglobin and myoglobin derivatives)
 Plant pigments
� Chlorophyll
� Anthocyanins
6. Enzymes in food processing, food quality and safety
7. Toxic constituents and anti-nutrients in foods and elimination their
 Factors Influencing Enzyme Activity
� Temperature
� pH
� Water activity
� Ionic Strength
� Chemicals
– Chelating agents
– Reducing agents
 Enzymes in Food Processing
� Polyphenoloxidase
� Pectic enzymes
� Amylases
� Lipolytic enzymes
� Lipoxygenase
� Peroxidase
� Ascorbic acid oxidase
� Antioxidant enzymes
 Desirable and undesirable changes in quality
 Stopping enzymatic brownining in fruits and vegetables
 Definitions: Toxicant, toxin, poison, toxicity, antinutrient
 Major inherent toxicants in plant foodstuff
� Types
� Their chemical nature
� Main food sources
� Major toxicity symptoms
� Mode of action (mechanism of
toxicity)
� Means of elimination.
 Anti-nutrients
8. Review and seminar  Assigned seminar topics in groups of 3 to 5 students (team work)
 Review summary
Interactive lecture, audio/visuals,
LCD projector and Computer for small and large group directed discussions and writing assignments/exerc ises (9 hrs);
Experimentation and Laboratory exercises (6 hrs);
Seminar topics power point presentation;
Lab equipment, materials and chemicals for experiments
Interactive lecture, audio/visuals, small and large group directed discussions and writing assignments/exerc ises (3 hrs);
Experimentation and Laboratory exercises (6 hrs);
Seminar topics
Interactive lecture, audio/visuals, small and large group directed discussions and writing assignments/exerc ises (6 hrs);
Seminar topics
Chalkboard
/White board;
LCD projector and Computer for power presentation point
Oral presentations and submission written reports group of group by
Chalkboard
/White board;
LCD projector and Computer for power point

5. SUMMARY OF TIME NEEDED
Interactive lectures covering theory 45 hrs
30 hrs Laboratory, Seminar
6. OVERALL COURSE EVALUATION
Continuous Assessment Test
Class practicals, exercises, Write-ups
University examination
20%
20%
60% learners;
Discussions ;
Questions and answers(6 hrs) presentation; Flip charts