Food Preservation Methods

TEACHING UNIT 1. OBJECTIVES AND METHODS FOR PREVENTING FOOD CONTAMINATION.

1. Prevention of chemical and physical changes. Chemical changes: Oxidation of fats.
2. Non-enzymatic browning. Enzymatic browning. Physical changes. Color changes.
3. Changes in texture.
4. Prevention of microbial spoilage and foodborne illnesses. Factors that influence the type and number of microorganisms present in food. Microbial spoilage in different food groups. Foodborne illnesses.
5. Asepsis. Raw material hygiene. Hygiene, cleaning, and disinfection of facilities and equipment. Cleaning. Disinfection. Performing cleaning and disinfection procedures. Personnel hygiene.
6. Preservation treatment. Physical treatments. Chemical treatments.
7. Product conditioning and consumer information. Use of controlled and modified atmospheres. Packaging. Consumer information and labeling.

TEACHING UNIT 2: PHYSICAL METHODS OF FOOD PRESERVATION.

1. Various physical preservation treatments. Mechanical cleaning. Wet methods. Dry methods. Combined methods. Filtration. Drying. Conventional dehydration. Freeze-drying. Smoking.
2. Salting. Pressure. Osmotic pressure. High pressure. Ultrasound. Electricity.
3. Temperature-related preservation treatments. Low-temperature treatments. Refrigeration. Freezing. High-temperature treatments. Scalding (or blanching).
4. Pasteurization. Sterilization.
5. Physical conservation treatments involving radiation. Microwaves. Infrared radiation. Ultraviolet radiation. Ionizing radiation.

TEACHING UNIT 3: CHEMICAL TREATMENTS FOR FOOD PRESERVATION.

1. General information on food additives. Definition and use. Organizations that regulate food additives. FAO/WHO. Council of Europe. European Union (EU). Spanish food law.
2. Health considerations. Criteria for evaluating the safety of a food additive. Toxicological testing of food additives. The concept of Acceptable Daily Intake (ADI).
3. Preservatives. Legal status of preservatives. Preservatives authorized for food use. Uses and mechanisms of action of preservatives authorized for food use. Sorbic acid and its salts. Benzoic acid, its salts, and esters of hydroxybenzoic acid. Acetic acid and lactic acid. Propionic acid and its salts. Sulfur dioxide and sulfites. Nitrites and nitrates. Antibiotics. Other preservatives.
4. Antioxidants and antioxidant synergists. Legal status of antioxidants. Antioxidants authorized for food use. Antioxidant synergists authorized for food use. Mechanism of action and uses of antioxidants authorized for food use. Ascorbic acid and its derivatives. Tocopherols. Gallates. Butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT). Sulfur dioxide and its derivatives. Lecithins. Mechanism of action and uses of antioxidant synergists authorized for food use. Lactic acid and its salts. Citric acid and its salts. Tartaric acid and its salts. Phosphoric acid and its salts.
5. Legislation on preservatives, antioxidants, and antioxidant synergists. Royal Decree 142/2002 on food additives other than colorants and sweeteners.

TEACHING UNIT 4. PRODUCT PACKAGING AND CONSUMER INFORMATION.

1. Use of Modified Atmospheres. Advantages and Disadvantages of Modified Atmosphere Packaging. Gases Used in Modified Atmosphere Packaging. Packaging Materials and Equipment. Applications of Modified Atmosphere Packaging.
2. Packaging. The need for packaging. Packaging materials. Wood. Paper and cardboard. Metal. Glass. Plastics. Polymer films. Filling and sealing of packages.
3. Food Packaging Requirements. Meat. Poultry. Fish. Milk and dairy products. Eggs. Fruits and vegetables. Other products.
4. Consumer Information: Labeling. Introduction. Labeling Regulations. Provisions of Royal Decree 1334/1999 related to food preservation.