19 Sep 2007
Beyond the Obvious
Regardless of whether you are enrolled in a weight-management program or a muscle building program, there are plenty of "danger zones" that will inhibit your success. Beyond the obvious such as drugs, alcohol and tobacco, there are several danger zones that are not as obvious.
Modern technology has given us food processing. Let's take a look at how different types of food processing can affect us.
Exposure to Heat
Heat can create and adverse effect on foods. The following are just a few examples of how certain processes can affect the foods we eat.
Fried Foods- The longer a food is fried and the higher the temperature -- the more vitamin and mineral potency loss will occur. Frying temperatures usually reach 375°F. Corn or safflower oils are best because of their higher smoke points of 450°F to 500°F.
Canned Foods- Vitamin and mineral potency losses occur from blanching. Then, the foods lose even more nutrients through the sterilization process, which involves temperatures of 240°F or higher for 25-40 minutes.
Frozen Foods- Many frozen foods are cooked before freezing. Higher quality foods are generally sold as fresh. Lower quality foods are generally used in frozen foods.
Dehydrated Foods- The damage to food through dehydration is dependent on the quality of the product processed. Certain methods of commercial dehydration use temperatures of 300°F.
Dairy Products- Many vitamins lose their potency or are destroyed by the pasteurization process. The homogenization process breaks down the normal-sized fat particles, thus allowing the formation of an enzyme called xanthine oxidase. The enzyme then enters the bloodstream and may destroy vital body chemicals that would ordinarily provide protection for the coronary arteries.
Exceptions- Various nutrients have different degrees of stability under the conditions of processing and preparation. Vitamin A is easily destroyed by heat and light. Vitamin C also is affected by heat. However, it also is affected by contact with certain metals such as bronze, brass, copper, cold rolled steel, or black iron processing equipment.
Studies conducted on the canning of foods found that peas and beans lose 75% of certain B vitamins, and tomatoes lose 80% of their naturally occurring zinc content.
Exposure to Cold
Foods exposed to low temperatures also can be adversely affected. For example:
Frozen Foods- Freezing may have only minimal effect on the vitamin and mineral potency depending on the method used. Also, the food is less effective if it's frozen shortly after being harvested. Remember, in most instances, the higher quality foods are sold fresh.
Fresh Fruits and Vegetables- Sometimes, foods are harvested before they are ripe. They are allowed to ripen on the way to market. This may cause a reduction of some trace minerals.
Note Some foods may retain more nutrients because they are frozen shortly after being harvested. A Stanford University study showed that frozen spinach had 212% more Vitamin C than fresh. Frozen brussel sprouts had 27% more Vitamin C than fresh.
Note During processing, more Vitamin E is lose than any other vitamin. Wheat flour (not the 100% whole wheat flours) loses up to 90% of its Vitamin E value. Rice cereal products may lose up to 70% of their Vitamin E.
How foods are stored plays a big part in determining how much nutritional value foods when they get to your plate.
Preservatives- Preservatives help maintain freshness and prevent spoilage caused by fungi, yeast, molds and bacteria. Preservatives are used to extend shelf life or protect the natural color or flavors of foods.
Acids/Bases (alkalis)- These agents provide a tart flavor for many fruit products. They also are used for pickling and making beverages "fizz" using phosphoric acid.
Antioxidants- Antioxidants reduce the possibility of rancidity in fats and oils. The most common natural antioxidants are Vitamins C,E,A and Selenium. Artificial antioxidants are BHA and BHT.
Taste Enhancers- These agents bring out the flavor of certain foods. MSG (monosodium glutamate) is a good example.
Improving Agents- Examples of improving agents include: Humectants- which control the humidity of a food. (2) Anti-Caking Agents- keep salt and powders free flowing. (3) Firming and Crisping Agents- used for processed fruits and vegetables. (4) Foaming Agents- for whipped toppings. (5) Anti-Foaming Agents- keeps pineapple juice from bubbling over a filled container.
Emulsifiers- These help evenly mix small particles of one liquid with another, such as water and oil. Lecithin is a good example.
Note Keep in mind that you are rarely aware of the quantity of additives you consume.
Flavorings- There are approximately 1,100 to 1,400 natural and synthetic flavorings available. Scientists are most concerned regarding the toxicity of many of the flavorings. Flavorings make food taste better, restore flavor lost in their processing and can improve natural flavors.
Stabilizers/Gelling Agents/Thickeners- These are used to keep products in a "set-state" such as jellies, jams and baby foods. They are also used to keep ice cream creamy. They generally improve consistency and will affect the appearance and texture of foods. The more common ones are modified food starch and vegetable gums.
Colorings- Ninety percent are artificial and have no nutritional value. Some foods have a tendency to lose their natural color when processed and must be dyed back to make them more appealing to the consumer. An example of this is banana ice cream which is dyed yellow. Cherries are almost always dyed.
Sweeteners- The United States' consumption of artificial sweeteners is estimated at approximately six pounds per person per year. These are designed to make the foods more palatable.
Aroma Enhancers- An example is a yellowish-green liquid-diacetyl which is used in some cottage cheeses to produce an artificial butter aroma.
Washing/Soaking- Many vitamins are water soluble and will be lost through washing, scrubbing or long periods of soaking. Soaking carrots causes the loss of natural sugar, all the B vitamins, Vitamin C and D, and all minerals except calcium.
Dicing/Slicing/Peeling/Shredding- The smaller you cut fruits and vegetables the more surface is exposed to temperature changes, the air oxidation, and light. Prepare as close to serving time as possible. Shredding for salads causes a 20% loss of Vitamin C and an additional 20% loss if the salad stands for an hour before eating it.
Note: The skin of fruits and vegetables contains at least 10% of the nutritional content of that food.
Charcoal- Benzines may be produced by the fat dripping on the charcoal. These chemical substances are classified as carcinogens (cancer forming agents).
Crock-Pot- Vegetables left in all day or for a long period of time lose a high percentage of their vitamins and minerals, as well as absorbing the fat from the meats. Steam vegetables first and then add them to pot before serving.
Boiling- Stewing and boiling fruits and vegetables result in heavy nutrient losses.
Steaming- This is by far the best method for preparing fruits and vegetables. They are subjected to high temperature for only a short period of time.
Microwave- Very good method, foods cook fast and therefore have less chance to lose their nutrients.
Frying- High heat causes nutrient losses in all types of foods. Meats will lose Vitamin B1 and Pantothenic acid.
Note: Refrigerate all foods as soon as possible, this will help you retain the potencies of the vitamins and minerals. Whole boiled carrots will retain 90% of their Vitamin C and most of its minerals, but if you slice before cooking you will lose almost all the Vitamin C and niacin content.