A lot of cookware is made out of aluminum, in part because of how strong it is and how evenly it distributes heat. Aluminum that is “hard anodized” is even stronger thanks to a sealant process that strengthens the metal and makes it even more durable. Hard anodization is an electro-chemical process in which aluminum is placed in an acid bath and given an electrical charge. This causes a controlled oxidation to occur — the aluminum combines with oxygen at the surface to produce aluminum oxide. Hard anodized nonstick cookware is cookware that has undergone this process followed by an application of a traditional nonstick coating. The end result is a pan that is very hard and usually also quite heavy that food will not stick to during cooking.
The process of hard anodizing was originally developed for use in the restaurant industry. Chefs desired heavy durable pans to hold up to the abuse of cooking many meals per day. Consumers who were able to sneak looks at the heavy durability and darkened colors of hard anodized cookware found it highly appealing, which ultimately led to widespread availability for home use.
By far one of the most praised features of the cookware is its durability, which is to say, how thick and heavy it is. Hard anodizing produces an extremely durable pan that has twice the hardness of most stainless steels. It also resists abrasion and corrosion; the surface will not chip or peel and it can handle extremely high heat levels without damage to the finish.
Hard anodized aluminum has the same atomic configuration as regular aluminum. This means that nonstick surface sealants are able to bind to the anodized cookware as easily as they do to regular aluminum cookware. The advantage is that, in most cases, it will hold up much better than on standard aluminum pans.
With standard aluminum, regular cooking and usage of utensils begins to break down the nonstick coating. As it breaks away in small places, food is able to make contact with the aluminum. This contact creates new chemical reactions that break down the nonstick surface more quickly. A hard anodized surface does not allow this to happen because the surface is too hard to allow cracks.
Variations in Quality
Though hard anodized nonstick cookware is generally held out as a top-of-the-line product, not all manufacturers maintain the same quality standards. Beginning with a low-quality aluminum can detract from overall pan performance, for instance; similarly, an inexpensive non-stick coating that is applied cheaply or in a rush can break down over time, all but destroying the usefulness of the pan or pot to which it is attached. As such, customers are usually wise to look beyond just the price of products they are considering. Researching the quality and manufacturing practices that have gone into making a given pan can be a good way of ensuring that the investment is a good one.
Care and Handling
Chefs and other cooking professionals usually recommend that all hard anodized nonstick cookware be hand washed in warm, soapy water. Though some manufacturers may say that their pans are dishwasher-safe, cooks can help extend the lives of their cookware by taking the time to clean them independently. Some dishwasher soaps can be harmful to the nonstick coating, and some pans will warp if exposed to the spinning ultra-hot suds used in many modern appliances. Handles and other decorative elements may not be able to withstand dishwasher heat, either.
A number of medical studies have made tentative links between aluminum and diseases like Alzheimer's and certain cancers, which has caused some consumers a bit of trepidation about purchasing cookware with aluminum in it. In nearly all cases, hard anodized pots and pans do not raise these concerns, though. The anodization process is believed by most to make the aluminum safe for consumers to use. The finish is chemically stable, will not decompose, and is absolutely non-toxic. Since hard anodized nonstick cookware will not usually chip and wear, it is arguably even safer than standard nonstick cookware.
Nonstick coatings raise a few of their own independent health concerns, though. Certain nonstick coatings can emit potentially toxic fumes when heated to very high temperatures. Inexpensive or poorly cared-for coatings can also begin to disintegrate over time, which can lead to flaking that may get into whatever food is being cooked. Experts usually recommend buying only top-quality nonstick cookware to avoid these problems; making sure that the coating is cared for — not using metal utensils or abrasive cleaners, for instance — might also help.