Learning outcomes of the course unit
Give to the students a synthetic but exhaustive vision of the chemical composition of food, illustrate the chemical changes that occur during the shelf-life, the main conservation techniques and some analytical procedures that lead to the chemical characterization of the main food products.
Basic knowledge of general, organic and analytical chemistry
Course contents summary
Principal and secondary components of food. Dietary fibre, simple and complex lipids, nitrogen compounds, vitamins, colorants, aroma compounds, mineral salts, other secondary compounds. Main food products, conservation techniques, food additives. Main proteinic food, milk and diary products, eggs, meat, fish; oils and fats; food rich of carbohydrates, sucrose, cereal meals, bread, pasta, fruit and vegetables. Fermented food, wine, beer, vinegar. Tonic food, coffee, tea, cocoa. Functional food, nutraceuticals. Analytical techniques for quality control and healthiness of food. Quality molecular markers.
Definition of food, nutritional characteristics, tables of percentage composition, Kieldahl proteins, Soxhlet and lipids. Soluble carbohydrates, starch, fibre. Secondary components, mineral salts, vitamins. Potable water quality, technical treatments. Mineral waters. Simple and complex carbohydrates, structure, reactivity and functional properties. Soluble and raw dietary fibre. Main industrial carbohydrates, production of sucrose, invert sugar, glucose, fructose and lactose. Starch hydrolysis and dextrines. Reactions of sugars with acids, bases and heat, thermal formation of HMF, lactulose, furosine. Maillard reaction, sugars fermentation. Nitrogen substances of food, origin, structure and properties. Natural free and protein amino acids, protein structure, thermal degradation, racemization, deamination, decarboxylation and formation of isopeptydes. Strecker reaction, xenobiotics formation. Enzymes of food industrial interest, enzyme kinetic: Km, Vmax. Hydrophilic and lipophilic acidity, hydroxy-acids and fatty acids. Simple and complex lipids, triacylglycerols, insaponifiables. Isomerisation and oxidation processes of fatty acids and sterols, reaction with oxygen and ozone. Molecular markers of lipid oxidation. Antioxidants. Substances responsible of colour, aroma, taste and consistence of food.
Characteristics of the main food products: cow milk, composition and thermal conditioning, butter, cheese, yogurt, milk serum by-products. High protein foods fresh and transformed, eggs, meat and ham, fish. High lipid foods: table sugar, rice, cereal meal, bread and pasta. Fibre rich foods: main classes of fruits and vegetables. Special foods: aromatic herbs, spices, fungi. Tonic beverages: coffee, tea, chocolate. Fermented foods: wine, vinegar, beer. Food preservation techniques by heating, freezing and chemical additives. Classification of food aromas. Environmental, industrial and packaging contamination of food. Notice on dietary supplements, OGM food, dietetic, functional, nutraceutical foods.
1) Chimica degli Alimenti - P. Cabras - A. Martelli Piccin Nuova Libreria Padova
1° ed. 2004.
2) Chimica degli Alimenti, last ed. - P. Cappelli V. Vannucchi - Zanichelli Editore - Bologna
Assessment methods and criteria
written and/or oral examination