Food Can Information
The canning process
First, the ingredients are cleaned and sterilised. Vegetables and fruits are washed and trimmed. They are also usually blanched to kill surface bacteria and set the colour.
No preservatives are used, as canning is itself a preservation process. Only water, syrup, seasoned liquid or oil is added to flavour the food and fill up the can. This minimises airspace in the can for a tight vacuum.
Individual ingredients, like beans, vegetables and fruits are cooked right in the can. Prepared food like curries and stews are fully cooked before canning.
The cooking temperature and time vary:
- Ingredients with naturally high-acid contents (pH lower than 4.6), such as
certain fruits, condiments and vegetables go through minimal cooking.
- Low-acid food (pH higher than 4.6) like most vegetables and all proteins
must be canned at high temperatures (250°F), often for 12 minutes or
more, or at least 3 minutes.
After cooking, the cans are placed in cold water baths. As the contents cool down, any steam that was created inside the can precipitates back into liquid. This leaves behind a vacuum, which prevents the content in the can from spoiling.

The benefits of canned food
Since food was first available in cans in the early 19th century, canning has grown to become one of the world’s most popular food packaging and preferred method of preserving food. Here’s why:
Freshness
Most canning facilities are located near the point of harvest. Canners use only top quality ingredients, which are picked, prepared and canned within hours or a day or two. The ingredients are sterilised through fast cooking at high temperatures.
Long shelf life
The canning process destroys organisms that would cause spoilage, maintaining the food’s high eating quality for two years. This shelf life is the longest among packaging solutions, clearly a mark of quality.
Preservation of nutrients
Canning is one of the safest ways to preserve foods. The can is completely sealed and the food inside is cooked and stored in a vacuum. The shelf life of canned food is at least two years, without the use of preservatives. Best of all, the vitamin levels in canned food remain stable during the shelf life.
Although some vitamin C is lost during the heat treatment, much of it dissolves in the cooking liquid and can be recovered by using the liquid in soups and sauces.
Some varieties of canned food even contain higher level of nutrients such as Vitamin A and calcium, compared to fresh ones or freshly cooked food.
Convenience
Canned food is cooked food. It just needs some warming up before serving because it has already been cooked. Using it in casseroles, soups, stews and desserts cuts down on time needed for preparation and cooking, and saves energy too.
Safety
Canning is one of the safest ways to preserve foods. Food is prepared for canning within hours of harvesting. Washing and peeling removes pesticide residues while the high heat process of cooking the food destroys bacteria.
Steel cans also have high resistance to tampering, providing 100% barrier against oxygen, CO2 and light. Any damage (rust, dent, bulge or leak) to the packaging is clearly visible and serves as a warning sign that the contents inside is no longer safe for consumption.
Friendly to the environment
Steel cans won’t lose strength or quality despite being recycled over and over again.
Tips for using canned food
Canned food can last about two years, without losing its nutrients and taste. But they still need to be stored properly.
- Always store canned food according to the instructions on the can.
- Keep canned food in a cool, clean and dry place below 30 ºC. The best temperature is between 10 – 20ºC.
- Canned fruit juices can be stored up to 3 years but keep an eye on the expiry date and follow the storage instructions on the can.
- Although some canned food can last up to two years, canned meat and seafood are best used within 12 months.
- With high-acid canned food, use within 6 to 8 months as the acid can react with metal.
- Got many tins of canned food? Practise ‘first in, first out’ usage.