There are a few different methods you can use for preserving food you harvest from your garden.
Salt was an important historical preservative but it is still used today for preserving a range of produce. Food to be preserved is typically dipped in a concentrated salt solution, which draws out moisture from the food. This prevents food-spoiling micro-organisms from growing in the food. Salt is most commonly used to preserve:
- Meat, including fish
- Sometimes fruit
If you want to preserve food using salt, table salt in not suitable due to the anti-caking agents added. Rock salt, or curing salt (for meat) are good alternatives.
Sugar solutions, like salt, preserve food by drawing out moisture. Sugar is typically used to preserve fruit (jam and jelly are good examples), however it is also used in combination with vinegar to preserve vegetables or vegetable and fruit mixtures. Chutney is an example of food preserved in this way. Fruit cheeses are also preserved using sugar.
Vinegar preserves food because its acidity prevents the growth of micro-organisms. Vegetables are typically preserved in vinegar.
Alcohol is an effective preservative because it kills micro-organisms. It is usually used to preserve fruit.
Oil and Fat
Although not actually preservatives, oil and fat protect food from exposure to air. This prevents food from coming into contact with new micro-organisms but in order to prevent spoilage from micro-organisms that are already present, food must be processed, typically by salting or cooking.
Drying can prolong the storage life of both fruit and vegetables. Drying is also used to preserve flowers.
Freezing and Refrigerating
Cooling food down slows micro-organism activity and growth, extending possible storage times. Check the crops section of this website to see if your produce can benefit from cold storage.