Tuna salad. A Friday Lenten food I've been eating all my life. There are three main ingredients--a can of tuna, pickle relish, and mayonnaise.
But how does it fare when given a natural spin? It took some time to find all-natural pickle relish. I finally did, in Whole Foods. Mayonnaise I have not found yet. Thinking that mayo itself is a set of simple ingredients whisked together (oil, egg yolks, lemon juice, vinegar), an all-natural version shouldn't be difficult to find. However, all the brands of real mayonnaise at the store contained EDTA.
No, not the Educational Theatre Association or the Electric Drive Transportation Association, as Google would have it.
Here, EDTA refers to ethylenediaminetetraacetic acid. The FDA has approved its usage in salad dressings, sauces, mayonnaise(s)? and varieties of canned beans, even in substances that contain dried bananas. (3)
Like disodium phosphate, EDTA is a sequestrant. EDTA binds to metallic ions such as copper and nickel, lead and mercury. Normally, the presence of these metallic ions in a fatty food like mayo would catalyze (or speed up) the breakdown of fats, and the mayo would go rancid faster. EDTA binds to these ions, rendering them unable to affect the breakdown rate of fat. (1)
EDTA is also used to treat heavy metal poisoning. While powerless against the musical stylings of Kiss, Disodium EDTA introduced into the body binds with the lead and mercury ions before they can be absorbed into sensitive tissues (2).
So EDTA is helpful in the medical world, but the question remains: should we be eating it? The European Amino-Carboxylates Producers Committee states, "There is at the present time no indication of harmful effects of EDTA due to long-term exposure to low concentrations" (5).
Three thoughts follow, which have not been tested or researched to my knowledge.
1)EDTA may prove beneficial when mayonnaise is incorporated into a tuna salad, because the sequestering properties of EDTA may bind to the mercury in the tuna, saving the body from absorbing harmful mercury.
2) EDTA may sequester beneficial metallic ions such as magnesium, calcium and iron, minerals the body needs. EDTA could keep a can of black beans fresher, longer. But how much of the iron cannot be absorbed by the body because EDTA inhibits absorption? Is the nutritional information on the can accurate?
3) Why not just buy black beans in a bag? Why not just make your own mayo?
EDTA UPDATE (03.31.2010)
After skimming the Whole Foods list of unacceptable ingredients, I noticed Calcium disodium EDTA and general EDTA are listed as "unacceptable." After a little more research it seems that all-natural foodies claim EDTA is toxic to a notable degree, especially when baking soda and ascorbic acid (Vitamin C) are other ingredients in the food, such as in soda (6). Perhaps the main reason Whole Foods bans this ingredient is because EDTA, also used in industrial products and cleaners, is a major polluter(6).