Local foods are a fantastic choice year around as the produce is harvested and sent to market right away or stored in proper conditions for the winter, preventing the breakdown of nutrients and flavour. However, when preparing meals or recipes in the winter or during the ‘off season’ that require vegetables such as peas, broccoli, peppers, celery, green beans, corn, etc., should we opt for fresh, frozen or canned?
Imported, fresh vegetables in the winter can be quite expensive. Furthermore, these vegetables are grown for transport and stability as opposed to flavour and nutrient content. Imported vegetables are also harvested before fully ripened in order to increase the shelf life and are therefore unable to produce their full spectrum of nutrients and flavours on the vine. Finally, many vegetables are treated with ethylene gas in order to ripen them during transportation, which can produce a mealy, flavourless product. As imported products may have up to three weeks between harvest and intake, there may be as much as 50% fewer nutrients in the product as nutrients deteriorate as soon as a vegetable is harvested. At the same time, fresh vegetables are still a source of nutrients and antioxidants and can be handy in the winter months.
Frozen produce is convenient and can be inexpensive. Such vegetables are generally sliced and ready to go and can be added to any cooked meal from frozen. Produce that is grown for freezing is harvested, blanched (with the exception of fruit and some vegetables) and flash frozen for maximum nutrient retention. Blanching the vegetables will deactivate enzymes that breakdown nutrients and flavour after harvest. Although the vegetables lose some nutrients during the blanching process, there is minimal nutrient and flavour loss during freezer storage. Frozen vegetables should be cooked from frozen in order to retain texture, flavour and nutrients.
You can also freeze your own fruits and vegetables for the winter. It is best to purchase locally grown produce during peak season, where it is least expensive, and then freeze the fruits or vegetables individually on a tray before storing in the freezer in oxygen-free containers (or reusable freezer bags). By freezing individually, you can grab one portion at a time throughout the winter months. In order to retain texture in cooking, you may also want to blanch the vegetables before freezing them.
In terms of canned foods, there is some controversy around the BPA in aluminum cans, however, purchasing no to low sodium canned goods can be an inexpensive alternative to frozen or fresh, just make sure to rinse them well before use. Although some nutrients are lost during the canning process, some canned vegetables, such as tomatoes, may actually be nutritionally superior to their fresh counterparts due to the release of nutrients from cell walls during the cooking/canning process.
In the end, choosing local vegetables year around is likely the best option, but there are times where imported foods come in handy, especially throughout the winter months. All vegetables, whether fresh, canned or frozen, help us meet our daily vegetable needs
(about 2 cups) and depending on your lifestyle and what works best for you, any or a mixture of the above options will do.
Eat Well Halifax,
Nicole Marchand, RD