Fresh food versus frozen or canned – Is one better for you?
There are many reasons why you may consider buying frozen or canned foods over fresh at the moment, such a supply being limited, financial constraints, or the inability to get out to the supermarket regularly. Here we explain how it is possible to get an abundance of nutrients from frozen and canned foods.
Fruit and Vegetables
Frozen vegetables and frozen soon after harvesting, meaning they retain more nutrients than fresh vegetables that are stored in the fridge for days. The same is true for frozen fruit. Preparation is important though. You may be more likely to boil frozen vegetables, leading to some of the nutrients being lost into the water (particularly water soluble nutrients including B vitamins, folate and vitamin C). Steaming is the cooking method that retains the most nutrients.
Tinned vegetables have similar levels of vitamins and minerals as fresh vegetables do, as they are canned shortly after harvest. One major difference though is that tinned vegetables can be much higher in sodium (salt), as they’re usually canned in brine (salty water). Draining and rinsing them before eating reduces the salt consumed.
Tinned fruit has the peel removed, making it less nutrient dense than fresh fruit with less fibre. However, some fruit intake is better than none, and fruit canned in juice rather than syrup is nutritionally preferable.
Frozen fruit and vegetables can last for 6-12 months in the freezer. Canned varieties can be much longer, up to 2 years (check the best before date). These can be a more feasible option that fresh fruit and vegetables, which can last up to 2 weeks refrigerated.
Fish and Meat
Canned fish contains comparable levels of key nutrients (protein and healthy fats) as fresh fish, and has a much longer shelf life. Canned salmon can be nutritionally superior if the small soft bones are also consumed, as these provide a valuable source of calcium.
Tinned meat such as spam and frankfurts is made from ground pork with flavouring agents and fillers, and has a long shelf life. These meats are high in fat and salt. They are a reasonable source of protein but do not contain as much as unprocessed meat. As a highly processed meat, the Australian Cancer Council recommends avoiding these due to the links with increased cancer risk.
Lentils and Legumes
We typically buy lentils and legumes dried or canned. It is possible to buy some beans fresh, such as fava beans, but they are much harder to come by and have a short shelf life. Dried varieties of legumes and lentils can last many years if stored correctly. Tinned varieties will last for 1-2 years.
Preparation of dried legumes and lentils takes much longer, some requiring hours of cooking and overnight soaking. The convenience of tinned varieties therefore increases their appeal. In terms of nutrition, canned and dried are on par, however canned varieties contain much more sodium (salt) than dried. There are low salt options available in some brands.
Prepared by Kara Vogt – Accredited Practicing Dietitian
