The aim of the course is to provide students with the fundamental principles and methods for low-temperature food storage. The main systems and equipments used for chilled/frozen food production and storage will be discussed, as well as the major quality attributes of raw materials and chilled/frozen foods.
At the end of the course and after the final exam, the student will be able to: - Write technical sheets for raw materials and chilled/frozen foods. - Plan and optimize frozen food and ice cream composition and processing parameters in order to assure product safety and quality. - Organize and manage the cold chain to guarantee chilled and frozen food quality. - Co-operate to the development of new products and to the improvement of production process.
Refrigeration: Methods and equipments for pre-refrigeration and storage of fresh vegetables and fruits, with or without modified atmosphere. Minimally processed refrigerated fruits and vegetables: production process and quality attributes.Refrigeration cycle and equipments:Pressure-enthalpy diagram. The ideal and the real vapour-compression cycle. Properties and environmental impact of refrigerants. Components of a vapour-compression refrigeration system: compressors, condensers, expansion valves, and evaporators. Household refrigerators and freezers. Fundamentals of freezing: Ice formation kinetic. Freezing curves of pure water, solutions, and foods. Physical and chemical changes during freezing and frozen storage in plant and animal tissues. Thawing kinetic. Quick-frozen foods: Quick frozen foodstuff legislation. Facilities for the cold chain. Freezing methods and equipments: Air convection freezing: heat transfer coefficient, weight loss, defrost systems. Air blast, fluidized bed, and impingement freezers. Contact freezing: plate, drum, and belt systems. Liquid immersion and cryogenic freezing: principles and equipments. Freezing process selection criteria (costs, yield, product quality). Production processing: Frozen fruit and vegetable production: quality attributes and processing lines. Production of frozen fish, shellfish, and related products: quality and safety attributes, processing lines. Artisanal and industrial ice cream production: ingredient functionalities, processing lines, quality attributes.