Free THAT’S THE WAY THE COOKIE CRUMBLES by Dr. Joe Schwarcz Page A

breaks the protein membrane, the fat particles come together, and the cream rises to the top. This effect may be desirable when we’re making butter, but not when we’re making ice cream. There is a simple solution: we can add an emulsifier to the mix. Emulsifiers are molecules that take the place of the protein membrane, since one end dissolves in fat, and the other in water. Lecithin, found in egg yolk, is an excellent example. That’s why even the simplest ice cream recipe requires some egg yolk.
    There is nothing like freshly made ice cream. Its smooth, airy consistency affords us a break from reality; it’s a throwback to childhood and a less complex world. Storing ice cream, however, does present a problem — the dreaded heat shock. By taking the container out of the freezer, for example, we may cause the surface of the ice cream to melt. When it refreezes, it forms larger ice crystals, resulting in the crunchy texture that so terrifies ice cream lovers. The commercial solution? Add some wood pulp.
    Now, don’t get all worried — we’re not talking about adding sawdust to ice cream. Microcrystalline cellulose is a highly purified wood derivative that sops up the water as ice cream melts and prevents it from refreezing into crystals. Cellulose is indigestible, and it comes out in the wash, so to speak. Guar gum, locust bean gum, or carrageenan, all from plant sources, can also be used for the same purpose. Although lecithin is a good emulsifier, there are others that are more commercially viable. Mono- and diglycerides or polysorbates disperse the fat globules very effectively.
    For those of you yearning for homemade ice cream but unwilling to deal with the salt and ice, here’s a solution. Find a chemist friend who can provide you with some liquid nitrogen and supervise your activity. Place the mix in a Styrofoam container, add liquid nitrogen, and stir. The mix freezes almost immediately and develops just the right foamy consistency as the nitrogen evaporates. With a little practice, you can outdo Nancy Johnson.
    A final word of warning, though. Ice cream may be addictive. A study conducted at the U.S. Institute of Drug Abuse suggests that eating it stimulates the same receptors in the brain as certain drugs. If you run into this problem, you may want to sample one of the new flavors that commercial manufacturers are tinkering with. Garlic, spinach, pumpkin, or tuna ice cream is sure to curb your craving.

Man Cannot Live on Corn Alone
    Italian cuisine is one of my favorites. Except for polenta. I have never developed a taste for that odd corn mush, which was once a dietary staple of poor Italians. When explorers returned home to Europe from North America with corn, it quickly became popular with landowners because of its abundant yield. These landowners often paid the farm workers they hired to grow the corn with a share of the crop, and corn became an important part of their diet.
    By the late 1700s, however, it was becoming evident that the sharecroppers who subsisted on corn were an unhealthy bunch. One could easily recognize them by their crusty, reddened skin. “Pellagra,” from the Italian for “rough skin,” became a common term for the condition. Most people believed that it was caused by eating spoiled corn. Rough skin was not the only symptom the poor sharecroppers had to worry about. The disease was often characterized by a red tongue, a sore mouth, diarrhea, and dementia — before it killed its unfortunate victim. Pellagra came to be referred to as the disease of the “four Ds”: dermatitis, diarrhea, dementia, and death.
    By the early 1900s, pellagra had reached epidemic proportions in the southern U.S. It ravaged the poor, especially cotton pickers. Some sort of a communicable infection now seemed a more probable cause than contaminated corn. Rupert Blue, the U.S. Surgeon General, stepped in and assigned his top epidemiologist, Dr. Joseph Goldberger, to solve the mystery of pellagra. Many