Criteria for method selection to determine food composition. Procedures for food compositional analysis (water and water activity, sugar and carbohydrates, fat, proteins, and micro-components) . Analytical methods to verify the conformity to law requirements in selected foods: milk and dairy, olive oil, wine, bread, and pasta. Practical experiences in laboratory with data acquisition, interpretation and writing of technical report
- Analisi dei Prodotti Alimentari
P. Cabras e C.I.G. Tuberoso
Piccin Editore 2014
-Chimica degli alimenti
P. Cabras e Martelli
Piccin Editore, 2004
-Food Analysis,
Susan Nielsen
Kluver Academic, Plenum Publisher, New York, 2003
-Course handbook and slides available on e-learning platform
Learning Objectives
Knowledge
chemical composition of food products and relevant analytical methods;c hemical-physic parameters relevant for compliance to law specifications; main chemical-physic alteration reactions (Maillard reaction, Lipid Peroxidation); relationships of food chemical composition with environmental and processing factors.
Competence acquired (at the end of the course):
To be able to select an analytical method test in relation to a specific task. To be able to indicate the general experimental condition of an analytical method; To be able to interpret an instrumental response in terms of product specification.
Skills acquired (at the end of the course):
To be able to define an experimental procedure in relation to a specific task; to be able to perform an analytical procedure (titration, spectrophotometry, pH); to be able to compute product specification from instrumental responses. To be able to write a technical report of practical experience.
Prerequisites
Courses recommended, not mandatory: Chemistry, Organic Chemistry, Analytical chemistry, Biochemistry
Teaching Methods
ECTS: 6
Total hours of the course: 48
Hours reserved to private study and other individual formative activities: 102
Contact hours for: Lectures (hours): 34
Contact hours for: Laboratory (hours): 10
Contact hours for: Laboratory-field/practice (hours): 0
Seminars (hours): 0
Stages: 0
Intermediate examinations: 4
Further information
Teaching tools
e-learning platform UNIFI
slides
DAGRI laboratory – via Maragliano equipped with a instruments for simple analytical determinations (titrations, pH-meters; UV-VIS spectrophotometers
Type of Assessment
The exam verifies the acquisition of the knowledges needed to correctly design and conduct a chemical/physical analysis to verify the composition of a food product according to technical characteristics and law requirements. The acquired skills are tested by verifying the ability of selecting the most appropriate chemical/physical analysis in relation to a specify a specific task and the capability of designing the most common chemical/physical analytic procedures. The appropriateness and adequacy of the technical language are evaluated too
Course program
General part
Compositional analysis of food:
Moisture and Water activity. Moisture determination: oven drying methods, distillation procedures, chemical methods.
Crude fat analysis: solvent extraction methods: continuous, semi-continuous, discontinuous. Elevated pressure/temperature solvent. Non solvent wet extraction methods: Gerber and Babcock. Introduction at IR and NMR techniques for fat content determination.
Carbohydrate analysis: total carbohydrate and total reducing sugar. Enzymatic methods for determining glucose content.
Protein analysis: Kjeldhal method, colorimetric assay: Biureto, Lowry, Coomassie. UV absorption.
Fat characterization: determination of physical chemical indices. Lipid peroxidation. Measuring oxidation state: peroxide value, conjugated dienes and trienes. Lipid composition: principles of chromatography for characterization of lipid fraction.
Protein separation and characterization procedure: separation by differential solubility, principles of chromatography for characterization of protein fraction. Separation by electrophoresis.
Special
Milk components and their physical state. Evaluation of milk thermal treatments by means of enzymatic indicators (alkaline phosphatase and lactoperoxidase). Maillard reaction. Physical chemical indices: density, pH, acidity, cryoscopy index.
Phenolic composition and sensory properties of wine. Anthocyanins and wine color. Assessment of functional properties of tannins: Phenolic and technical grape maturity indices.
Olive oil composition: triglycerides, fatty acids, minor polar fraction. Chemical physical characteristics of natural fatty acids: determination of fatty acid in 2-monoglicerides. Assessment of conformity to botanical origin. UV-VIS assay. Determination of eritrodiol and uvaol content in rectified oils. Determination of elaidinc acid content. Phenolic compounds and olive oil stability and sensory properties.
Flours: chemical and physical indexes for correct composition and storage of kernels and grinding products. The composition of wheat flour; the rheological properties of the doughs.