By Danniel Arriaga
Do you ever just wonder how they determine calories and fat content in our foods? Or is it just me? These are obviously not just made-up numbers, right?
That’s right. I spoke with Jacinda Dunn, a fourth year undergraduate at the University of Tennessee in Knoxville, majoring in food science. Dunn is spending her summer in the George Washington Carver (GWC) Internship Program in Iowa State University’s College of Agriculture and Life Sciences. Her mentor is distinguished professor of animal science Donald Beitz, and her project focuses on fatty acid composition in meats.
The GWC is a program that allows students, who are at least 16 years old, to experience life on campus here at Iowa State, as well as work in the laboratories. Students are assigned a project to research that their mentors are working on or give the students a brand new project. The students stay in the dorms and experience life on campus for eight weeks.
“The whole concept is to allow a student like Jacinda to be in a laboratory setting, where she can see what’s going on. In a classroom setting you get asked questions by the professor, as opposed to a laboratory setting, where you get to ask the questions,” Beitz said.
While working in Beitz’s lab, Dunn has learned how to use a gas chromatograph, which is an instrument that separates fatty acids of different chemical structures on the basis of flowing through columns at different rates. A detector is placed at the end of each column to quantify the separated fatty acids. A chromatogram is a readout of the results that looks like a series of peaks. The area under the peaks is proportional to the amount of the given fatty acid represented by the peak.
The questions they are trying to answer are what is the fatty acid composition of this piece of pork? Does it have more or less unsaturated fatty acids? What’s the percent lipid, what’s the fat content?
But the big question I wanted to know was: Who cares?
You should. The everyday citizen should care, and sometimes you can even catch them in the act. Have you ever heard the phrase, “I wonder how much fat is in this?” while you’re out to lunch or dinner? Fat content matters a lot to people, especially those who are calorie conscious or have serious heart problems.
“If somebody has a heart attack, the doctor might say Mr. So-and-so you need to change your diet, I know you’re eating way too much fat. So then that person needs to know something about fat content in food,” said Beitz.
All of this seems like a lot to handle especially for a 21 year old, like Dunn. What makes her want to charge forward?
“I hope to expand my curiosity, you know, discovering new things daily and helping others. I want to be a resource for people to use when he or she has a concern about the foods we eat on a day-to-day basis,” Dunn said.
Dunn grew up in Memphis, Tenn., before moving to Knoxville. She is a positive person who thanks her mother for pushing her to do better in life. When Dunn first began the GWC program, she thought it might be all work and no play. Now after being a part of the program for a couple weeks, she loves the program and the activities, like the ropes course at the Iowa 4H Center in Madrid. She as well loves the coordinators and other interns, like they were her second family.
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Jacinda Dunn in the lab. |
So what does Dunn have waiting for her in the future? Right now she is working mainly on data collection, which means mainly computer work. Later on she’ll be working in the lab, extracting fatty acid samples from pork chops. Her mentor, Beitz, also has planned for her to visit and learn about her coworkers (graduate students, post-docs, other staff) and their backgrounds.
All the research topics in the GWC are diverse and different, introducing students like Dunn to new sciences and careers in science. The George Washington Carver Internship program funded by the College of Agriculture and Life Sciences has brought in hundreds of students to conduct research at Iowa State over the past decade.
Danniel Arriaga, a student at Roosevelt High School in Des Moines, is spending the summer as part of the George Washington Carver Internship and is also part of the program, Science Bound. He is an intern in the College of Agriculture and Life Sciences’ Communications Office, writing news stories about the other GWC interns.