Adding salt or sugar Makes water unavailable Increases salt and sugar Food examples: for microbial growth. content of food. Process does not destroy nutrients. High heat processing (e.g. Inactivates autolytic Loss of heat-sensitive Food Examples: pasteurisation) enzymes nutrients. Destroys microorganisms. Canning (involves high heat Destroys microorganisms & Water-soluble nutrients can Food Examples: processing) autolytic enzymes. be lost into liquid in can. Equipment: Chemical preservatives Prevent microbial growth Some people are sensitive to See question C some chemical No loss of nutrient. preservatives. Ionizing radiation Sterilizes foods (such as Longer shelf life of fresh Food Examples: spices) whose flavour foods can lead to greater would change with heating. nutrient losses than if eaten sooner after harvesting. Inhibits sprouting potatoes Extends shelf life of strawberries and mushrooms
Adding salt or sugar Makes water unavailable for microbial growth. Process does not destroy nutrients. Increases salt and sugar content of food. Food examples: High heat processing (e.g. pasteurisation) Inactivates autolytic enzymes Destroys microorganisms. Loss of heat-sensitive nutrients. Food Examples: Canning (involves high heat processing) Destroys microorganisms & autolytic enzymes. Water-soluble nutrients can be lost into liquid in can. Food Examples: Equipment: Chemical preservatives Prevent microbial growth No loss of nutrient. Some people are sensitive to some chemical preservatives. See question C Ionizing radiation Sterilizes foods (such as spices) whose flavour would change with heating. Inhibits sprouting potatoes Extends shelf life of strawberries and mushrooms Longer shelf life of fresh foods can lead to greater nutrient losses than if eaten sooner after harvesting. Food Examples:
fn-12-preservation-notes-1lqb6v1.docx