FOOD CHEMISTRY - RECEPTOR CHEMISTRY
Learning outcomes of the course unit
Knowledge and understanding
During the course the student will acquire a deep knowledge of the chemical
composition of foods, of the characteristics of the different components, of their
influence on the food properties, of their reactivity and of the transformations they
undergo during the technological processes as well as of the analytical issues
linked to their determinations.
The student should acquire the ability to correlate and integrate general aspects
with specific characteristics of the different food products, understanding the
correlation existing between chemical composition and quality and acquiring the
ability to elaborate label informations.
These knowledges are the base to effectively operate in the production, control and
analytical sector as well as to design new products and processes.
Applying knowledge and understanding
The student must be able to utilize the acquired knowledges to understand and
foreseen the molecular transformations in foods as a consequence of technological
processes and storage.
The student must be able to define which transformations may occur or may be
induced in a food and which are the effects of the different formulations on the
general properties and the quality of a food product as well as to identify the
processing or storage conditions that may influence the overall quality of a product.
The student should be able to appropriately utilize the scientific language and the
specific lexicon of food chemistry, showing the ability to describe and transfer in oral
and written form the acquired concepts.
The student will be able to increase his/her knowledge of Food Chemistry, by self-
consultation of specialized texts, scientific and divulgative journals, also beyond the
topics discussed during the lessons.
At the end of the course, the student should be able to:
Knowledge and understanding: To be acquainted with the chemical and the physico-chemical bases that regulate the operation of receptors; to understand the mechanisms through which small molecules activate or block nuclear or membrane receptors
Applying knowledge and understanding: The student must show to be able to synthesize their knowledge, their ability to analyze and understand the structure-activity relationships for classes of drugs through devising and sustaining critical arguments in the field of medicinal chemistry, proving to be able to have a professional approach to discipline
In addition, the teaching aims to achieve autonomy of judgment and Communicative Abilities.
Making judgments: Students will be able during the lessons, to interact with the themes suggested by the teacher and, even with the help of the recommended texts and teaching materials, be able to make independent judgments
Communication skills: The student must be able to clearly and critically present the results of their individual calculations, demonstrating knowledge of research topics carried out during the program
Learning skills: to be acquainted with a method of study and analysis that is tailored on the student and efficient, in order to extend the field of knowledge to different disciplines and in order to make his preparation suitable to higher-learning experiences.
Students should have already passed the examinations of General Chemistry,
Organic Chemistry and Analytical Chemistry.
Organic Chemistry , Medicinal Chemistry , Biochemistry , Physiology , Pharmacology
Course contents summary
The Food Chemistry course is composed of a first general part focussed on the description of food macrocomponents (water, carbohydrates, proteins, lipids) and of their chemical, physical and technological properties, the study of their general reactivity as well as of the analytical methods to assess the proximate composition of food products.
The second part is focused on the description and characterization of functional food, mainly in terms of bioactive components. Finally, the course will provide an overview on novel food, in term of description, characterization and requirements, also taking into account detailed case-studies.
The course of Receptor Chemistry is composed by the following topics:
1) Structure of receptors
- Binding receptor/molecule of interest
- inhibition of receptors
- In-depth analysis of peculiar classes of receptors
1) Nuclear receptors
- molecular basis
- definition of a steroid hormone
- nomenclature and chemical structure of steroid hormones
- biosynthesis of steroid hormones
- mechanism of action of steroid hormones
3) Female sex hormones
4) Male sex hormones
5) Hyperlipoproteinemia and cardiovascular disease
- the cholesterol and other blood lipids
- cholesterol biosynthesis
6) HMG - CoA reductase inhibitors ( statins )
7) Medicines to treat diabetes
- type 1 diabetes
- type 2 diabetes
8) Oral hypoglycemic
Introduction. What is Food Chemistry? Water. Water structure. Interactions of water with food components and matrices. Bound water, water activity (aw): definition and correlation with % equilibrium
relative humidity. Sorption isotherms: meaning and use. Methods for the
determination of % humidity of foods (dehydration, distillation, Karl-Fischer titration,
IR, NIR, thermobalance), of ash (in oven orwith acids) and water activity (hygrometers, lithium chloride sensors, dew point
sensors). Mineral waters (potability characteristics and compositions).
Carbohydrates. Monosaccharides and oligosaccharides in foods: structure, properties and occurrence. Cane and beet sugar. Inverted sugar, glucose syrups:
preparation and applications. Alditols: preparation and application. Decomposition
of sugars in foods with acids, alkali and heat treatment. Hydroxymethylfurfural,
maltol and isomaltol, lactulose. Caramellization and caramels. Maillard reaction.
Methods for analysis of carbohydrates. Polysaccharides. Starch. Gelification and
retrogradation. Modified starch and starch syrups. Amylases. Pectins. Pectinesterases and pectinlyases. Algal polysaccharides (alginates and carragenans). Cellulose, hemycellulose and fibers. Methods of analysis of food
fiber. Gums (arabic gum, xanthan gum). Physico-chemical properties of polysaccharides and their applications in food products. Fermented products:
alcoholic beverages, wine, vinegar and beer. Lipids. Fatty acids: structure and their
occurrence in foods. Melting points and physical properties of oils and fats. Reactions of unsaturated fatty acids. Hydrogenations, margarine and trans fatty acids. Degradation oxidative reaction and rancidity (autooxydation, fotooxydation
and enzymatic oxydation, lipooxygenases). Natural and synthetic antioxydants:
classification, properties and mechanism of action. Control parameters for oxydation
phenomena in oils. Triglycerides. Crystalline forms of triglycerides: fat melting and crystallization. Chemical composition and properties: cocoa butter and chocolate. Interesterification. Vegetal oil, milk fat, cream and butter: classification, composition,
production and refinement. Emulsions. Natural and synthetic emulsifiers: characteristics and applications. HLB parameter. Sterols. Polar lipids. Cholesterol and phytosterols: chemical characteristics, occurrence and stability. Analytical
methods of fats.
Proteins. Amino acids and proteins in foods. Degradation reactions of amino acids
and proteins in foods: heat and pH effects. Denaturation, racemization, isopeptides,
lysinoalanine, furosine. Analytical methods. Technological properties of proteins
(humectants, emulsifying, foaming, gelling, etc.). Proteinaceous foods. Milk:
classification, structural components of milk, caseins and serum proteins, casein
micelle structure, lipids and fat globules, lactose, thermal treatments and
homogenization of milk and effects on milk components, analytical methods of milk.
Cheese: classification and composition, coagulation and chemical modification
during ageing, proteolysis, proteolysis index, nitrose fractions, principal analyses.
Meat and fish: classification and composition, characteristics of meat proteins, postmortem
changes, anomalies (DFD, PSE), myoglobin and meat colour, additives, cured meat products (sausages), principal analyses. Eggs: composition, characteristics of egg proteins, technological properties, egg products. Cereals and
derivatives: chemical composition of cereals, cereal proteins, classification and properties, gluten: formation and properties, flour and semola, rheological properties of flours, bread and pasta, bread additives, effect of heat treatment and drying.
Food color. Molecular bases of color. Color measurement: colorimeters and spectrophotometers. Natural colors: chlorophyll, carotenoids, antocyanins, betalains, melanins, curcuma and cochineal red. Synthetic dyes.
Flavour: aromas and tastes of foods. Taste: sweet, bitter, salty, acid, astringency, hot, umami. Aroma: meat, fruits, vegetables, aromatic herbs and spices, synthetic flavouring agents, off-flavor and contaminants. Sensorial analyses.
Additives. Classification and numbering. Chemical properties of food additives (preservatives, antioxydants, emulsifyers, ecc.). Vitamins. Classification. Properties,
analyses and degradation reactions in foods. Undesirables. Toxicological aspects. Classes of undesirable components in foods. Phytotoxins. Toxins in animal
products. Mycotoxins. Bacterial toxins. Allergens. Toxic residues from agriculture. Heavy metals. Toxic substances from thermal treatments. Toxic compounds from packaging. Environmental pollutants.
Mannina, Daglia, Ritieni – La chimica e gli alimenti: nutrienti e aspetti
Gragam L. Patrick, Chimica Farmaceutica, III edizione Edises
During the lessons, which will be done using power point projections, overheads
and blackboard, the different aspects of foods and of their production will be
presented, with a particular emphasis on the chemical and physical
transformations and their control.
The course will be conducted through lectures . Each lesson is a teaching module unit , in which , for each topic , are given to the student the foundation for acquiring knowledge and understanding , and to apply the knowledge and understanding to the problem treated in the unit of learning module.
Assessment methods and criteria
Final examination will be written. The written examination will contain open
questions on the main course topics, both on the aspects of the most important
chemical reactions and on the descriptive aspects of food composition and
properties and of food components.
The final evaluation will be based on a written exam.
The final exam will be made of multiple answer questions, to be selected by the students. To each answer will be applied a score, that can be also negative if the answer is not correct. In the same cases, students will be asked to draw and/or describe the mechanism of some reactions.
The exam is passed when the final score is equal or more than 18/30.
The final score will be the arithmetic mean of the scores of the two modules.
Attendance to the lessons is not mandatory, although strongly encouraged.