Wednesday, April 7, 2010

Policy Point Wednesday Fresh vs. Preserved - what are the real issues?

Fresh foods are getting a lot of press lately, especially in the discussion of school lunch.  Of course, there are certain advantages fresh foods have when it comes to nutrition - but those advantages probably aren't the ones that immediately come to mind when you're strolling the produce aisle. 

Preserving food is an ancient art.  Most of us can easily imagine American frontiersmen filling their stomachs with foods like hardtack and pemmican, but preserving food goes back to pre-Colombian times:  meat and potatoes were dried and stored all over the Americas.  Ancient Egyptians dried and ate fruits like dates and figs, and still do, today.  In his excellent book, Cod, Mark Kurlansky discusses the profound impact preserving this fish had on the political development of both Europe and America.  Preserving food has allowed for survival during hard times throughout history.

I think of processed foods slightly differently, though one could argue that "processing" is an overly broad term.  Most people think of "processed foods" as foods that are preserved in a factory or manufacturing plant.  Many of the preserving techniques factories use today were discovered somewhat by accident over the course of the last three hundred years (fairly recently, in the scheme of things.)  The technique we know as canning was discovered on the early side of that curve by a candymaker working to keep Napoleon's army fed; he reasoned correctly that if foods could be kept airtight and then cooked, they would keep.  Frozen food was "discovered" by an arctic explorer who found that meats left in subzero temperatures tasted the same as fresh when cooked - he created a "Multiplate Quick Freeze Machine" that became the freezer we all know and love today (I have two.)  These leaps forward in food preservation technology allowed for a much improved quality of life for nearly everyone; out-of-season produce was made available to the masses instead of only the very rich who could afford food grown in greenhouses.

Flash forward to more recent times and processed foods start getting into trouble:  mass-marketing, mass-manufacturing and wildly extended shelf lives converge to produce cheap foods of minimal nutritional value that might possibly become edible antiques.  Food desert "fringe foods" are in this category - they contain preserving agents, many of which are quite ordinary: salt, fats, sugars, starches - but they contain little else.  They do, however, last nearly forever on a gas-station shelf; if a product doesn't sell, it has quite a long time to sit there waiting to be purchased.

On the flip side, the limited shelf-life of fresh meats and produce are a distinct disadvantage, even when you take economics out of the picture.  Fresh products need careful handling and their nutritional quality can degrade over a very short time.  Most produce varies in nutritional quality as it comes in and out of season.  One could also cite the danger of microbially contaminated fresh products as a disadvantage - although proper refrigeration, washing, and cooking makes this a minimal risk.  It can't be overlooked, though, that fresh foods are more likely to go to waste, and therefore their cost increases exponentially all the way down the production line to the farm.

So, are fresh foods better nutritionally?  Well, that's kind of a complicated question: a recent study by the University of Illinois showed that canned foods retain, and in some cases may even increase, the nutritional benefits of their fresh counterpart.  However, the study tends to gloss over the fact that many canned foods contain added salt or sugar - often more than a consumer would add to the corresponding fresh product.  The same holds true for frozen foods, that is, provided you are buying the vegetable, fruit, or meat on its own (canned meats, except fish, are NOT nutritionally similar to their frozen or fresh counterparts.) 

If fresh foods are more wasteful and don't provide better nutrition than preserved foods, what did I mean when I said fresh foods have certain advantages?  Well, it's much easier to build a healthy diet around them - fresh beans are fresh beans - nothing more, nothing less.   A can of boston baked beans, though...not so much like our fresh beans.  Unfortunately, many, many preserved foods are convenience foods, a conglomerate of individual foods, preservatives, tasty fats, salts, and sugars that are ready to eat right out of the can or bag.  Food in its raw state rarely has fatty, salty, or sugary surprises.  (Keep in mind sodium or fat can be added to fresh meat, sometimes disguised on the label with words like "broth," or "pre-brined," or "basted."  Additives can also be hidden by grinding meats - hamburger has more (cheaper) fat than whole-muscle beef.  It's a good idea to check labels either way, even if a food is minimally processed.)

Once we let food companies do our cooking for us, we take away the opportunity to manage our diet.  Food companies are in the business of making food that sells - food that's easier and tastier sells better - and food that's cheaper brings more profits.  Unfortunately, this translates into high sodium, high sugar, and high fat foods.  The nutrition label is your shield against fringe foods in the food desert.  Don't trust health claims on the front of a package - while they are required to follow truth in advertising laws, the information they provide might not be relevant in the context of your dietary needs.

So, to me, the answer to our dietary woes is not fresh food alone - though, if you aren't in the habit of reading labels, stick to fresh foods, since, well, a fresh raw beet isn't going to contain anything but beet.  To me, being somewhat thrifty -  the answer is to read the labels, buy foods as close as possible to their fresh counterparts - and to prepare them in my own kitchen.  My general rule of thumb: five ingredients or fewer - and double-check the salt, sugar and fat.  It's served me well throughout this project.

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