Thursday, April 21, 2011

Discover Covers Cooking, Genes and Fracking

The May issue of Discover magazine reveals one insight after another.

The cover story, about the latest findings on our evolutionary ancestors, filled me in on our relatives. DNA analysis has revealed that European and Asian people's genes are between 1 and 4 percent Neanderthal, and that people from Papua New Guinea and nearby areas are up to 5 percent "Denisovan," another competing species of Homo that has only recently been identified. I find it amusing that it's African-descended people who don't share the Neanderthal genes, when typical white racists believe that whites are pure and other races are "mongrels."

The article Add a Pinch of Science tells the story of the 40-pound cookbook Modernist Cuisine by Nathan Myrhvold, and particularly shares some of its stunning photos, which often feature pans and food cut in half to reveal what's happening during the cooking process. I especially liked the photo of an orange being zested, with the essential oil spray causing a lit match to spew flame. And I learned the most about baking from a photo caption describing how a turkey roasts: "People focus too much attention on how the meat heats, even though how it dries in the oven is at least as important. What actually controls the baking of food in an oven is not the temperature you set but the humidity created by water evaporating from the food. A drier bird cooks faster, so start by using a rack to keep it out of its own juices, and base the bird with oil. This reduces the rate of water evaporation, raises the surface temperature of the meat, and consequentially speeds up cooking."

Fracking Nation gave the best summary I've seen of the contentious natural gas mining technique known as hydraulic fracturing or fracking. It focused largely on the Marcellus Shale, which lies beneath my hometown in upstate New York and other nearby states. This is the same area that, just today, I heard has been the site of a big spill of the toxic chemicals used in the "hydraulic" part of the equation. Fracking has the following problems:

  • It uses an amazing amount of water (2 to 10 million gallons per well)
  • The water, after use, is contaminated with toxic waste, representing a disposal problem (even when there isn't a spill)
  • The solids it leaves behind are radioactive
  • It may cause earthquakes
  • It's not the carbon footprint panacea everyone thought it was (a recent Cornell University study found that natural gas from fracking results in more greenhouse gas output than coal)
The Barnett Shale in Texas has been the site of fracking since the early 2000s, with over 14,000 wells in the area. According to author Linda Marsa, "Drilling operations have turned some of Texas's most affluent communities into industrial wastelands."

One positive development is noted at the end of the article: Fracking with gelatinized LPG gas instead of water is being tested in Texas. That may sound even worse, but what it means is that the LPG gas can be completely recovered and reused for the next well. No water is needed, and there's no contaminated water to store afterward. From what I can see, though, it doesn't help with the other drawbacks (radioactivity, earthquakes and total carbon output).

And here's one holdover article from the March issue of Discover: A North Carolina State University chemical engineer is working to create solar cells that operate like plant leaves. The cells are flexible and nontoxic, without the cadmium and other materials used in typical cells. They can be used to cover an irregular surface and can even be folded. The hangup so far: the cell is currently vastly less efficient than the best rigid, toxic ones.

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