The pros and cons of fresh, frozen and canned foods
Frozen and canned products usually take less time to prepare and can also be less expensive than fresh foods, but are they just as nutritious? Are fresh foods always the best choice? Is it always better to choose fresh foods? Let’s take a look.
Fresh is best!
What you need to know is that the fresher a food is, the greater its nutritional value will be (vitamins, minerals, and antioxidants). However, as soon as the food is picked, being sensitive to heat, light, oxygen, and processing, its nutritional value starts to decrease.
So, are fresh foods truly fresh?
We tend to think of “fresh” fruits and vegetables as being the best choice. From field or orchard to supermarket display can take a long time though, especially if the food is imported. A lot of the vitamin content is lost while in transit. So we have everything to gain by purchasing in-season, local foods, with the added bonus that they will have more flavor!
What about frozen foods?
Such frozen foods as fruits and vegetables are processed shortly after being picked. The deep freezing process is a technique that preserves the freshness, vitamins, and minerals of foods, hence most of their nutritional value too.
Frozen foods are pre-washed and often cut into pieces, which is a great time saver. They are also less expensive than when their fresh equivalent is out of season.
So what’s the problem? Unfortunately, even though processing is said to preserve flavor and texture, the frozen product doesn’t always meet consumer expectations. Moreover, some foods, like meat, fish, and seafood, may be laden with added salt, a preservative, so you should check the list of ingredients before purchasing.
And canned foods, do they keep their nutritional value?
The heating process involved in food canning destroys 30% to 50% of the vitamin content (vitamins of the B complex, vitamin C, folate, etc.) and antioxidants1. Minerals are more heat resistant, but dissolve in the water in which the food is canned. Other nutrients are better preserved though, like the fat-soluble vitamins A and E, which are more readily available after processing. This explains why canned tomatoes are richer in lycopene, an antioxidant, than their fresh equivalent.
As far as legumes (beans) are concerned (lentils, red kidney beans, chick peas, etc.), the nutritional value compares well to their dried equivalent. Attention must be paid though to the added salt and sugar content. This is why they should always be rinsed before eating. Rinsing also removes some of the sugars that cause gas.
Canned fish is also an excellent choice, since its omega-3 and vitamin D content doesn’t suffer during the canning process. Worthy of note is that mercury concentrations in canned pale tuna are lower than in white tuna.
A small tip: avoid foods from dented and rusty cans since the likelihood of bacterial contamination is greater.
Enjoy your grocery shopping!
By Karine Séguin
 Nos petits mangeurs. 2013. Les fruits et légumes surgelés et en conserve : un bon compromis. En ligne. < http://www.nospetitsmangeurs.org/les-fruits-et-legumes-surgeles-et-en-conserve-un-bon-compromis/>