From the moment they are picked, fruits and vegetables begin to lose nutrition, and they will continue to do so as you handle, transport, process, and store them. The article describes the impact of day-to-day food handling, and explains how to get the most nutrition out of your purchases.
We’re always told to wash our fruits and vegetables, and with good reason, considering the number of chemicals with which most conventional produce is cultivated. Washing vegetables, however, is often a waste of time and merely wastes nutritive elements on the exterior the produce.
The skin of fruit is typically the richest in vitamins and minerals, many times richer than the interior (for example, there are ten times more antioxidants in the skin of an apple than in the flesh). The leaves of vegetables, and often the roots, are also richer in nutrition.
If you purchase organic fruits and vegetables, you need not be overly concerned about washing them. Of course, no one likes the taste of dirt (though you might get a dose of Vitamin B12), and a quick rinse won’t hurt in attempting to eliminate potential pesticide residues and other pollutants (if you suspect your produce was grown near roads or conventional fields), but soaking (like berries, or washed and cut potatoes), scrubbing, or other zealous forms of washing are not necccessary.
Don’t wash your organic produce unless it’s truly neccessary; wash them just enough to lift visible dirt or other forms of life.
Cutting, shredding, and mixing:
Cutting produce with a knife is a great was to accelerate the loss of nutrients. A knife cuts a large number of cellular membranes, exposing cells to the air. Tearing produce, on the other hand, is a better way to preserve nutrition, as the produce is opened without tearing as many cellular membranes.
If you don’t believe me, take an apple. Cut it down the middle and lay the halves on the table. Take another apple and tear it down the middle with your hands. Leave for fifteen minutes or more. The apple cut by the knife will have oxidized faster.
Of course, knives are indispensible in the kitchen. No one is going to tear an onion for a salad. But, whenever possible, such as with broccoli, tear your produce, letting the natural structure of it guide you.
Shredding multiplies the surface area of produce 100 to 200 fold, allowing for rapid oxidation and loss of nutrients. We love carrots, beets, cabbage, radishes and other vegetables shredded, but know that preparing vegetables in this way destroys them rapidly. Make salads fresh, and add vinegar or lemon juice to it to slow the rate of oxidation, and to preserve Vitamin C (losses will be roughly cut in half).
Blending, like shredding, accelerates the destruction of vitamins. But, if the product ends up being liquid, the losses are reduced, as the product is somewhat self-insultating, and there is less surface area exposed to air. If not eaten immediately, keep the product in the fridge.
To ensure a maximum of vitamins and minerals from your produce, don’t shred them too fine, shred them at the last moment, be sure to add lemon juice or vinager, and never buy vegetables pre-cut or shredded.
Where & How To Store Your Produce:
Just as fresh fruits and vegetables have become more widely available—in supermarkets and farmer’s markets alike—we have seen a paradoxical increase in the consumption of conserved produce, from canned beans and corn, to frozen spinach, to jams, to tinned tomatoes. As people work longer hours and pile on superfluous “responsibilities,” they lose the time to shop for fresh food, let alone properly prepare it.
Against the invasion of processed food, thanks to the “agro-industrial complex” (sounds as frightening as the “military industrial complex”) we should ask ourselves the following questions:
-should we eat the vegetables from the supermarket, impoverished of vitamins given their long transport times and shelf lives; or should we eat foods that have been canned or frozen?
-if we choose conserved foods, which type of conservation should we favor?
The food industry might respond that losses in vitamines are fewer in well-conserved or immediately frozen foods than those in fresh foods that have traveled thousands of miles and sat in supermarkets for days. This isn’t exactly wrong, but what they fail remember is that a conserved product will continue to lose vitamines over the course of time.
As a general rule, avoid as much as possible any food item that went through some kind of factory.
If your produce isn’t coming from your own garden, you should do everything possible to procure it from farmers’ markets (most vegatbles and delicate fruits sold in these markets are picked within 36 hours of being sold), with a preference (if not an insistence) for organic; you should store your fresh purchases for as little time as possible in the refrigerator (meaning, you should eat them with immediacy), as we tend to abuse this priviledge, thinking things will remain fresh as long as they are cold—a total fallacy.
Storing Food At Room Temperature:
Certain fruits and vegetables conserve better at room temperature, or often in a cellar, rather than in the refrigerator. This is the case for the majority of acidic fruits and vegetables (agrumes?, tomatoes), alliacees? (garlic, onions, shallots), potirons doux?, and potatoes. Tomatoes picked before their ripeness must absolutely be stored at room temperature.
In The Fridge:
We’ve always been told—at least in America—never to leave foods on the counter for more than four hours, lest bacteria begin reproduce. But the fridge cannot guarantee against baceria. Certain types of bacteria will continue to proliferate at 4 degrees C, especially if your fridge is not cleaned regularly, and if you have the tendency to leave foods to age for long periods of time.
Even when in the fridge, vitamins will dissappear progressively. Losses vary from one type of food to the next. Vitamin C is by far the most fragile of vitamins and will begin to disappear rapidly. Vitamin C of raw vegetables stored in the fridge, for example, can easily lose up to a quarter of their Vitamin C over just two days. Cooked vegetables (such as leftovers from dinner, which have already sustained losses), can lose around 50% of their remaining Vitamin C in just one day.1 Hence, when you buy your fresh vegetables, keep them in the fridge (with the exception of the aforementioned) and eat them as soon as possible.
In The Cellar or Cool Pantry:
There are two main aguments for eating foods that have been canned or frozen: first, we simply don’t have sufficient time to prepare fresh foods; second, there is a paucity of local vegetables in the winter. I am reluctant to validate the first argument (people should make time), but can conceed the point.
The second argument, however, doesn’t hold much water. People with gardens who know how to utilize all of their resources know that they can have at their disposal numerous vegetables throughout the winter.
Some of these nutrient-rich (green) vegetables can remain in the ground (leeks, Brussels sprouts, winter greens, etc.) while others store very well in the cellar or in a cool pantry (away from central heating, which has a remarkable ability to make foods go off rapidly; think of your bread that went mouldy instead of stale). Potatoes and all root vegetables (suchs as carrots and beets) all store well for an entire season in a cool environment, and though they will sustain losses in Vitamin C over time, other vitamins will conserve well.
In The Freezer:
Freezing your produce is a great way to have them for later, such as in the winter. It’s easy to do, and it does a pretty good job of conserving color and flavor (unlike canning, which ranks lowest in appearance, taste, and nutrition).
What many people don’t know is that vegetables that have been blanched (immersed in boiling water for 1-2 minutes) actually keep better in the freezer than those that have not been. Blanching destroys the living enzymes in foods, thus inhibiting them from breaking down nutrients in the foods over time. For example, after six months, blanched Brussels sprouts can contain nearly all of their Vitamin C (with the exception of losses through blanching), whereas raw Brussels sprouts can lose up to half.
Despite the convenience of froozen foods—the ability to have any kind of food during any season—I do not advocate abusing the advantage. Seasonal foods confer certain appropriate properties, to which the body will be instinctively drawn, provided it knows how to listen (do not retard your body’s ability to discern its needs with the toxic inputs of refined, de-natured foods). It is better to keep your body in sync with the rhythm of the envinroment, and to eat what the seasons provide. This, in effect, will stimulate great satisfaction and gratitude for the foods you do eat, as you await their seasonal arrivals.
Jams, Jellies, Marmelades:
In my book, it’s junk food. Anything that is 50% added sugar is junk food and fundamentally poisonous and wearing to the body’s organs. Family tradition or not, there is little to gain from confitures besides a delightful dessert (under no circumstances should these be breakfast foods).
The cooking process, often exceedingly long, destroys the majority of vitamines sensitive to heat. The added sugar, typically refined, confers nothing of nutritional value. If one were to use less-refined sugars, these would typically only obscure the flavors of the fruits.
Do I renounce these preserves entirely? No. As I said, they are a dessert, and a pleasant one. People are encouraged to make their preserves with as little at 15% added sugar. This much sugar will allow for adequate conservation, will be less exciting to the pancreas, and should (hopefully) limit of addictive behaviors with sugar.
Throughout history, fruits were dried in the sun. Dried fruits, with honey, were the principle source of sugar (the fine, white powder we know today simply didn’t exist—ADD LINK). In a number of desserts, dried fruits can be used as a sweetener.
The destruction of vitamins through the dehydration of fruits is variable. Acidic fruits lose less nutrition than others. Not all dried fruits were dried equally. That is to say, most of the dried fruits found in supermarkts were dried rapidly at high temperatures (and furthermore, rolled in sugar); this detroys nutrition and enzymes.
You can dry your own fruits at home in the sun (if you feel so inclined), with an electric dehydrator, a solar dehydrator, or even in your oven at a temperature lower than 118 degrees (if possible). By not exceeding 118 degrees, you will not run the risk of destroying your vitamins and enzymes, but losses will occur, as with any form of processing.
The principle is thus: bacteria, naturally present on the surface of foods, transforms a part of a food’s sugar into lactic acid, which provokes a process of acidification. As long as the pH level of a food is around 4, harmful bacteria will not be able to proliferate, and the food will conserve well for a long time.
What is remarkable about lactofermentation are the many improvements it confers to foods: it pre-digests fiber; allows for easier amino acid assimilation; helps to tranform difficult starches (ones responsible for gas) into simple sugars; suppresses nutrition inhibitors in certain foods; and regenerates good intestinal flora.
Lactofermentaion also increases vitamin and enzyme conent. The Vitamin C level of lactofermented cabbage, for example, after a period of fluctuation, stabilizes at around 100% of its original value; one can see a thirty-fold increase in Vitamin B12, suggesting that vegans can indeed meet their B12 requirements.2
Insist on buying freshly-picked, organic produce at least twice a week (don’t let your produce sit in the fridge all week).
A quick rinse to lift dirt is all you need.
Prepare your vegetables just before eating them (rather than hours or days beforehand) and don’t hesitate to add vinegar or lemon juice to prevent oxidation.
Know that most of your vegetables should go into the fridge, and they do lose nutrition over a few days.
Root vegetables belong in the cellar/cool pantry.
Freezing (blanched) vegetables and fruits conserves nutrition well.
Canning is lowest on the list.
Confitures are a nutritional disgrace, but enjoy them as a dessert.
Lactofermentation is an extremely worthwhile investment of time, and a preferred method of conservation.