The Hiearchy: Fresh, Frozen, & Canned
The key hierarchy of foods is simple: Fresh is always best. The problem is fresh isn't always available, might not be economical, and usually lacks convenience.
So the hierarchy exists as fresh, then frozen, then (mostly in the case of fruits & vegetable) canned.
Fresh is at the top for the obvious reasons. There is no better way to eat or prepare a food than with the direct from nature version. Butcher grade meats and farm fresh fruits and veggies are awesome, as they've had little to no processing done to them. But factor in the three problems listed previously (availability, economy, and convenience), and it’s up to you to figure out if it is really worth it. A garden salad, sure you want fresh vegetables. Big Fourth of July barbeque go see the butcher for the best cuts of meat. Coming home late from work on a Tuesday and you promised a special someone a home cooked meal, time and effort chopping and slicing may be you downfall.
Frozen is almost as good as a nutritional choice, and in most cases a better choice on your time and wallet. Most of the nutrients in your veggies will be locked in, and you can stash it away until you want or need that meat or vegetable that you plan to eat. What you will most likely lose is prettiness and presentation. For example, I always have bags of frozen chopped onions and chopped green peppers to toss in to recipes, but if I'm looking for a dish to impress, I go out and buy a fresh onion and pepper so that I can chop them in big pieces for visual presentation. Or, for something like the green salad mentioned earlier, you don't want soggy, thawed vegetables.
Canned is considered by some a last resort, but for many it’s the best bet of all. It takes mere moments to open a can of vegetable and put it in a pot for a side dish ready in the time it take water to boil. And canned vegetables are usually cheaper and keep a lot longer. The actual downfall of canned goods is the canning process, which is believed to cooks away a lot of the nutrients from the food. I actually did some research on this for this posting, and found a link to a 1995 study entitled,
COMPARISON OF SELECTED FRESH, CANNED AND FROZEN FRUITS, VEGETABLES, LEGUMES AND PROTEIN FOODS which states that for the most part, commercial can foods are just as good as fresh or frozen. For home canning, here’s
THE OHIO STATE UNIVERSITY EXTENSION FACT SHEET ON BASICS FOR CANNING VEGETABLES, which tells home canners to prevent loss of flavor and nutrients, rinse all produce thoroughly but do not soak.
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COMPARISON OF SELECTED FRESH, CANNED AND FROZEN FRUITS, VEGETABLES, LEGUMES AND PROTEIN FOODS-
THE OHIO STATE UNIVERSITY EXTENSION FACT SHEET ON BASICS FOR CANNING VEGETABLES

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