Perspectives Online

Creative PedagogyIn Keith Harris’ award-winning class, food science, innovative technology and cool classroom experiences add up to teachable moments. By Terri Leith

Dr. Keith Harris Photo by Becky Kirkland

It’s mid-October and Dr. Keith Harris is scooping ice cream at the N.C. State Fair, but not just any ice cream. It’s the fairgoers’ favorite, the many delectable flavors of Howling Cow ice cream made fresh in the dairy processing center in the Department of Food, Bioprocessing and Nutrition Sciences (FBNS), College of Agriculture and Life Sciences. And it’s sold at the fair by CALS Food Science Club students, with help from FBNS faculty and staff, including Harris, assistant professor and faculty adviser to the club.

Coincidentally enough, earlier that week, ice-cream making was the stuff of an innovative classroom demonstration Harris conducted for students in his introductory food science course, FS 201, “Food Science and the Consumer.” To a recipe of half-and-half, sugar and vanilla, Harris added liquid nitrogen (-300 degrees F), not only achieving the dramatic effect of a billowing fog rolling out of the steel bowl but also producing in 60 seconds enough ice cream to serve all 100 students.

So while the fairgoers raved about the heaping cones of butter-almond, java-bean or pecan-crunch, these consumers of just plain vanilla were taking away much more — lessons about ice crystal formation and frozen foam and all the chemistry and physical science that go along with it.

FS 201 is now the required first course for food science majors, a popular elective for non-majors and, as of fall 2008, an online distance education course. For that online version, Harris was named 2009 winner of the Gertrude Cox Award for Innovative Technology Enhanced Courses. The annually presented Cox Award was created to honor the “creative pedagogy” of N.C. State University’s faculty and technical staff and their work “in integrating new technologies into effective teaching strategies.”

Liquid nitrogen puts the instant freeze on an in-class ice-cream-making demonstration and adds some drama to the food science lessons being taught by Dr. Keith Harris (with student Stephenie Barnhardt).
Photo by Becky Kirkland
As indicated in the award citation, Harris’ particular creative pedagogy involved using Moodle (an online learning management software) and other technologies to make FS 201 both an on-campus and a distance education class, providing opportunities to students in both physical and virtual space to learn what the course has to offer.

The citation notes that “the course deploys its technology seamlessly and very effectively, not only in bringing guest experts to both cohorts but also in using that expertise to demystify high-profile concerns from fad diets to chili peppers and peanut butter. Dr. Harris takes the science of nutrition and embeds it in the context of the students’ personal experience and current media events to make the teaching of biology relevant and fascinating to his students.”

As Harris puts it, “This course is designed to make the students more educated consumers by giving them the science — the chemistry, microbiology, engineering and nutrition — and the business, the marketing, of producing food. It’s really the integration of those. I hope after this course the students walk away knowing how food gets to market and how the food scientist can make foods safer, tastier and more nutritious.”

The course aims to provide a working knowledge of the application of chemical, microbiological and engineering principles to food formulation, preservation and processing. In doing so, it reveals things like what the ingredient polysorbate 80 actually does in a food or whether organic food is really healthier than regular food. Along with information about the complexity of food systems, students also learn about how food product marketing and sensory characteristics affect consumers’ purchasing choices, as well as the diversity of career opportunities available in the food industry.

The effects of diet on human health and athletic performance, facts about government regulation of food labeling and marketing, and comparative insights on global and U.S. food markets are also among the information presented in the classroom and online.

Harris decided to make it an online offering “because of its introductory nature. I thought I could communicate its content in both classroom and online format. In high-level classes I feel it is important to have face-to-face interaction on how to investigate current science. This introductory course offers basic vocabulary and basic chemistry, so when I explain the science behind food it will make sense. Then what I do to motivate them is make it fun. I feel I can do these things in face-to-face and online formats.”

And with the online offering, twice as many students were able to take the course in the fall 2009 semester than in the past.

While open to students across the campus, FS 201 is essentially an outline of what food science majors will be getting in more detail in future courses, Harris says, so it has just recently become their required first course.

Newly schooled in the chemistry of frozen foam, FS 201 students queue up to sample their experiment.
Photo by Becky Kirkland
One immediate lesson he teaches is that “food science is a tool that could be used well or used poorly,” he says. “If used well, it can be very effective, from a global perspective, in terms of how to produce nutritious food efficiently and deliver it safely. I try to deliver the science and my perspective of the best use of food science.”

The result? “The students enjoy it and are getting a lot of information,” he says. “Everyone comes in the course thinking they know food, and they learn that there are so many things they don’t know. This [course] helps fill in some of the missing pieces about food and the science behind food. There is a lot of science behind the thousands of food items in a grocery store, but it seems like such a mundane, everyday thing to go to there that the science can easily be overlooked.

“I try to peel back the layers of complacency and show there’s a lot of science behind everything from breakfast cereals to vegetables,” he says. “This is a science-based course, and we are dealing with the concept of weight of evidence. The things that we, as food scientists, talk about — such as the chemistry behind why bread turns brown or why omega-3 fatty acids may play a role in reducing heart disease risk — are said because a body of science backs this information.”

This particular week he’s teaching the science behind why food browns. “Browning reactions are due to enzyme activities, such as those that cause the bruising of fruits, the polymerizing of sugars in caramel candies or, in the case of roasting, frying or sautéing, can be caused by reactions between proteins and sugars — activities central to the foods’ color or flavor,” he says.

Students are often surprised by the browning reactions of foods and the application of other food science lessons that they learn in the class, such as the roles of proteins and carbohydrates, Harris says. “Students with chemistry or biochemistry backgrounds may know this, but the others may not, so this presents a unique challenge in making the class interesting to all of them.”

Making pancakes is one of the most fun browning activities, he says. “Pancakes are a comfort food that demonstrate many chemical reactions and browning reactions, as well as an example in foams — in this case a foam generated due to gas bubble formation by baking powder and baking soda. Protein stabilizes the foam, and sugar, combined with protein, makes it brown nicely.”

Another demonstration features the role of proteins in making meringue, formed as egg whites are whipped into a foam. “Egg white proteins unfold as a result of the strong shear forces caused by whipping and wrap around air bubbles like a 3-dimensional net,” he explains. “The protein gives the bubble a 3-D ‘hug’ and keeps it from bursting. In addition to the protein, the sugar in meringue not only makes it sweet, but thickens the mixture and also helps to keep bubbles from escaping and bursting.”

One discovery students make through these activities is “how many foods we eat are from foams,” Harris says. “Foam stability works in everything from cakes to bread to ice cream, which is a frozen foam.”

And that, of course, brings him to the 60-second ice cream.

“I take a big steel bowl, pour in the ingredients and have a student come help me stir,” he says. “Then I pull out the big dewar of liquid nitrogen, which is extremely cold and can burn you, if you are not careful. So I talk about safety issues as I do this and use a lab coat, thermal gloves and a wooden spoon, since wood does not conduct cold. As the liquid nitrogen is added little by little, it ‘boils’ and creates bubbles in the ice cream mix. As the mix, freezes, it thickens, trapping the bubbles.”

That’s frozen foam, composed of fat, protein and sugar. A rolling fog pours out of the bowl for a dramatic minute (“It presents students with a spectacle that I can use to fix scientific principles in their minds” says Harris), and the chemistry of instant vanilla ice cream has been demonstrated.

It’s all part of the exciting, interactive experience Harris has fashioned for students in the classroom and online — a course that has benefitted from the support of the FBNS Department, he says.

“Dr. Donn Ward, the department head, allowed me the freedom to reformat course content — FS201 has existed as a course for more than 30 years — and to communicate that content in a creative way. A variety of professors and department staff have served as guest speakers in their areas of expertise, and as ‘extras’ in course-related skits.

Harris pitches in with Food Science Club students to scoop Howling Cow ice cream sold at the N.C. State Fair.
Photo by Becky Kirkland
“We have taste-tested regular peanut butter against low-fat peanut butter in ‘The Great Peanut Butter Battle,’ with the help of one of our in-house sensory experts, Michele Yates. Students have heard about beneficial bacteria from Dr. Todd Klaenhammer, about food texture from Dr. Chris Daubert and about the science behind canned foods from Dr. Brian Farkas. Dr. Dana Hanson’s ‘Makin’ Bacon’ lecture in particular has been a student favorite.”

Another colleague, Joanna Foegeding, co-wrote the original grant that allowed Harris to begin creating an online version.

In addressing any issues of communicating course content effectively in an online environment, he credits Lee Ann Gillen of the university’s Distance Education and Learning Technology Applications (DELTA) as “an incredible resource in helping me with best practices and with accessibility for online courses.

“As a practical example, face-to-face lectures are not simply recorded and placed online. Although I do provide online students with PowerPoint slides and full-length MP3 audio of face-to-face lectures and weekly lessons, best practices for online courses says that this is not the most efficient way to communicate information in the online environment,” he says. “For that reason, the ‘Webisodes,’ or the weekly lessons that are the primary source of course content, are broken up into bite-size pieces, so that online students can also view course content in a variety of ways, including videos and short PowerPoint presentations with voice-over, as well as captioning for the hearing-impaired and links to Web sites that complement course content.”

Along with the DELTA staff, Daubert and Foegeding, “the department’s in-house experts on distance education,” helped him with the software and hardware for creating online content.

“Like any other successful project, FS201, whether in the face-to-face or the distance version, is a team effort,” Harris says. “I could not do what I do without the support of my department, the work of excellent teaching assistants or the incredible technical help of DELTA.”

Harris is himself a department alumnus, having received his 1997 master’s degree from N.C. State. He started out in community college before earning his 1995 bachelor’s degree from Morgan State University in Baltimore, Md., and his 2001 Ph.D. from The Ohio State University.

When not teaching students or advising them in the Food Science Club, Harris is conducting research on flavanoids, the polyphenol antioxidants found naturally in plants.

“Right now, we’re working on the anti-inflammatory or aspirin-like qualities of plant products. We’re investigating a variety of plants foods, such as green and black tea, muscadine grapes and purple sweetpotatoes. We look at both the antioxidant and anti-inflammatory properties,” he says.

“I’ve always been interested in health,” he adds. “A natural extension of that is how food affects health.”

Originally, as an undergraduate, Harris was interested in a career in dietetics, but his interests later shifted toward laboratory-based research. “Then my professor said I should attend a Food Science meeting – the Institute of Food Technologists (IFT) in Atlanta, and I was hooked,” he says. “There were 20,000 people at this huge meeting — all very business-driven. Companies allowed us to try their newest products.”

He was excited by what he found there: “an innovative industry, new foods we were able to try in this sprawling experience, and friendly people,” Harris says.

Among participants were food science students and faculty from N.C. State. “The reason I became interested in NCSU in particular is the people from there were the friendliest people,” he says, mentioning Dr. Duane Larick, professor of food science and dean of the N.C. State Graduate School, as example.

Now, as a faculty member he hopes to share that enthusiasm for food science not only with his N.C. State students but others, as well. “Adapting this online course to a community-college or high-school level course would be great,” he says.

“Because I started in community college, what I’d like to be able to do is build a bridge between high schools and community colleges and N.C. State. That’s what I’d like to accomplish — building that bridge.”