Food and science, two of my favorite things to indulge in, rarely meet on the same playing field (unless you indulge in the aptly named field of food science through a chemistry class called The Chemistry of Food and Wine). Yet food made its way into my classes on a few occasions this week, prompting me to think back on some other memorable moments at Pomona where tasty morsels and the wonders of science walked hand-in-hand.
1. It started this week in tectonics lab when my professor, Linda Reinen, walked into the room with a tote bag and tossed a Cara Cara orange to each of us. A bit confused, I rolled it around in my hand and noticed some markings on it.
If you examine the picture on the right, it probably doesn’t make much sense, but the orange is a mini representation of the earth, and the enclosed section (A) is representing a tectonic plate. B is also a tectonic plate, but it’s really just the rest of the planet in this little scenario. If you can see the line curving around on top of A with the little triangles, that represents a subduction zone where one plate is being pulled under another. The one way arrows on the margin between A and B represent a transform fault, an area where plates are in contact with each other, but crust is not destroyed (as in subduction) or created. The whole point of Linda spending her lunch drawing on eight oranges was to help illustrate how plates move on a spherical body and the concept relative rates of movement. Also, this type of orange (which I’d never heard of prior to Tuesday) is really good compared to your average orange, so I recommend people try it out, even if you don’t plan to draw on it.
2. I ended the week with a bit of food as well, this time in my general chemistry class with Prof. Fred Grieman. As our “reward” for answering enough questions and asking enough questions (although I suspect this little experiment would have occurred anyway), we made a glowing pickle. Yes, pickles can glow, and although you probably couldn’t substitute one for a lamp in my dorm room, it’s still pretty neat. If you want to see what it kind of looked like, I recommend checking out a video on Youtube. If you want to duplicate it (at your own risk, the thing does produce smoke after a bit), I recommend checking out this video. For a full explanation, you should probably ask a chemistry person, but the gist of this little phenomenon is that pickles, which are really cucumbers in salt solution, have lots of dissolved ions. Dissolved ions conduct a current, so when you stick metal rods into the pickle and run a current through it, the electrons in the ions get excited (move to a higher energy state). When they drop back to their ground state, they emit a photon of light, which in this case just happens to be yellow as a property of the sodium atom. It’s the presence of sodium ions rather than any magical property of cucumbers that’s really making this happen. That was the only food of this past week, but these two “experiments” aren’t the only times that food and science have collided.
3. X-ray diffraction (XRD) is achieved using a very expensive piece of technology to shoot x-rays at a powdered sample at various angles to determine crystalline structure and thus mineral content. The basic notion is that the crystal lattice may intercept and reflect or refract the beams, or the x-rays may just pass through. If you want to get all technical, the USGS can explain it to you. Of course, most stuff in the world is not crystalline. Glass for example is not crystalline. But they may contain crystalline solids within them (some pharmaceuticals for example). What better sample than a leftover Halloween Oreo? After running tests on all of the materials that we were actually supposed to be testing for our mineralogy lab, we split an Oreo, using a very scientific twisting technique, then smeared the orange paste onto a slide and put it in. Unfortunately, no crystalline structures in there, so perhaps we’ll have to try some other cookies in the near future…
4. The final story is from my favorite all-time lab. Last year, my Earth History class (Prof. Bob Gaines) was studying cladograms as a means by which to reconstruct evolutionary relationships. Nothing better for improving understanding than getting some hands-on experience, so Bob procured some well-preserved specimens of the clade known as ‘candybaria.’ Although this group sounds very exotic, their natural habitat includes your local gas station, Target, and snack pantry.
They’re fairly prolific and do not seem to be affected by the worrisome global climate change of our time. Getting back on point, there were several varieties of Hershey’s, Milky Way, Snickers, and everything in between (Twix, PayDay, Kit Kat, etc.). Our assignment? Build a cladogram based upon shared characteristics, such as the presence of a body cavity, smooth or rough skin, or the presence of symbiotic nuts. This also included taking into account which traits are more basal, which may have evolved and then been lost, which may have evolved separately, and whether the commonly accepted names are accurate indicators of evolutionary relationships. Some serious dissection expertise was required for this experiment. It would be nice to have a picture of our actual lab work, but unfortunately, all of our specimens mysteriously disappeared…
Of course, these are only my college experiences; my high school exploits include making “wine” by combining yeast and cheap grape juice in a test tube to study fermentation and anaerobic respiration, launching flaming gummy bears out of test tubes in chemistry, and watching my AP Bio teacher eat dry fruit fly food and proudly tell our class that it tasted like bananas. But those are stories for another time.