Following is a review of materials in popular use in cookware today. This review may serve as a guide to safe cooking.
More than half (52 percent) of all cookware sold today is made of aluminum. But most of these aluminum pots and pans are coated with nonstick finishes or treated using a process that alters and hardens the structure of the metal. Researchers still are investigating the connection between aluminum and Alzheimer's disease. But according to Creighton Phelps, Ph.D., director of medical and scientific affairs at the Alzheimer's Association, much recent data supports the theory that brains already damaged by Alzheimer's disease may permit entry of abnormally high levels of aluminum. In other words, Aluminum does not appear cause Alzheimer's disease, but people with Alzheimer's tend concentrate and store aluminum.
As FDA and researchers point out, aluminum is ubiquitous. It is the third most abundant element in the earth's crust (after oxygen and silicon). It is in air, water and soil, and ultimately in the plants and animals we eat.
Many over-the-counter medicines also contain aluminum. According to the Aluminum Association, one antacid tablet can contain 50 milligrams of aluminum or more, and it is not unusual for a person with an upset stomach to consume more than 1,000 milligrams, or 1 gram, of aluminum per day. A buffered aspirin tablet may contain about 10 to 20 milligrams of aluminum. Not all antacid and buffered aspirin contain aluminum. Read the product labels to determine if aluminum is contained in your medication.
Aluminum cookware manufacturers warn that storing highly acidic or salty foods---such as tomato sauce, all fruit products, rhubarb, or sauerkraut---in aluminum pots may cause aluminum than usual to enter the food. (Also, undissolved salt and acidic foods allowed to remain in an aluminum pot will cause pitting on the pot's surface.) However, 50 mg aluminum intake is virtually impossible to avoid, and when precaution taken the amount leached in food from aluminum cookware is relatively minimal. Aluminum can also leach from aluminum foil, do not store acidic or salty food in aluminum foil.
FDA reviewed existing data because of consumer concern and formally announced in May 1986 that the agency "has no information at this time that the normal dietary intake of aluminum, whether from naturally occurring levels in food, the use of aluminum cookware, or from aluminum food additives or drugs, is harmful."
One reason aluminum became popular for cookware is because it is an excellent heat conductor. Heat spreads quick and evenly across the bottom, up the sides, and across the cover of a pot to completely surround the food. Now cookware manufacturers have developed a process for treating aluminum that retains the heat conductivity properties of the metal, but changes aluminum in other ways. The process, called anodization, involves a series of electrochemical baths that thicken the oxide film that forms naturally on aluminum. Food barely sticks on the hard, smooth surface of this altered aluminum, making it easier to clean. Anodized aluminum cookware doesn't react to acidic foods, so these pots and pans are top choices for cooking fruits and sauces with tomato, wine, and lemon juice.
Because nonstick finishes may be scratched by sharp or rough-edged kitchen tools, manufacturers recommend using plastic or wooden utensils. Abrasive scouring pads or cleansers should not be used to clean them. Nonstick pans do abrade with heavy use and particles may chip off, if ingested particles pass unchanged through your body and pose no health hazard.
Cooking enthusiasts now are hailing Silverstone and Excalibur nonstick coatings, which are made of three layers of the same plastic used on Teflon and other perflourocarbon resin-coated pans. This material is extremely durable, inert and it will not migrate.
Consumers who do not use aluminum pots and pans usually typically use stainless steel. Stainless steel cookware and bakeware is exceptionally durable. Its attractive finish won't corrode or tarnish permanently, and its hard, tough, nonporous surface is resistant to wear. As stainless steel does not conduct heat evenly, most stainless steel cookware is made with copper or aluminum bottoms. Manufacturers caution against allowing acidic or salty foods to remain in stainless steel for long periods. Although there are no known health hazards from leaching of the metal, undissolved salt will pit steel surfaces.
Copper is an excellent conductor of heat, especially good for top-of-range cooking. Cooks often prefer copper cookware for delicate sauces and foods that must be cooked at precisely controlled temperatures. However, copper cookware is usually lined with tin or stainless steel. FDA's Thomas says that the agency cautions against using unlined copper for general cooking because the metal is relatively easily dissolved by some foods and, insufficient quantities, can cause nausea, vomiting and diarrhea.
Cast iron is strong, inexpensive, and is an even conductor of heat useful for browning, frying and baking food. Cooking with cast iron also provides a source of iron. Nutritionists suggest that foods cooked in unglazed cast iron contain twice or more times the amount of iron they would contain otherwise.
Cast-iron utensils should be handled differently from other utensils. To prevent rust damage, the inside of cast iron cookware should be coated frequently with unsalted cooking oil. It should not be washed with strong detergents or scoured and should be wiped dry immediately after rinsing.
Ceramic and Enameled Cookware
In 1830, a Bohemian craftsman found he could create a permanent, smooth, glassy surface on cast iron by finishing it with porcelain enamel. This highly durable glass is stain and scratch resistant and does not pick up food odors. Today, enamel-coated iron and steel provide colorful as well as practical additions to the cook's collection. Cookware made properly of enamel on these metals is safe to cook with, says Edward A. Steele, acting director, executive operations staff, in FDA's Center for Food Safety and Applied Nutrition. Steele says that because of the high firing temperatures required, lead---which could present a safety concern--is not used in the enamel for this cookware.
Lead, however, is used in some glazes for slow-cooking pots (crock-pots). But, in tests done in 1987, FDA found that the amount of lead that leached into food from these pots did not exceed FDA standards.
This information written by Anne Field, Extension Specialist, Emeritus, with references from the FDA Consumer newsletter.
Source: MSU Extension
Feedback about this article is posted here. Want to contribute? Click above to post feedback.
By non-stick (Guest Post)01/14/2008
I am very surprised that you neglected to include the hazards of non-stick coatings such as Teflon. Due to this gross over site I cannot validate the remainder of your article and will dismiss its relevance.
Editor's Note: This article is from MSU Extension. Please post the research if you have some good information on hazards of Teflon or non stick coatings.
Add your voice to the conversation. Click here to share feedback.