The study, published in the American Marketing Assn.’s Journal of Marketing, was conducted by Prof. Xiaoyan Deng of Ohio State University's Fisher College of Business, and Prof. Raji Srinivasan of McCombs School of Business at the University of Texas in Austin.
The project put subjects in the experimental study in front of a television. The environment makes sense; research shows approximately 70% of all snack products are consumed in front of the telly.
Then, researchers told subjects they would be reviewing ads running during episodes of a popular sitcom. The participants were fortified with a range of with snack foods to nosh on—some in transparent bags, others in opaque.
You might have guessed the study focused on the food, not the ads. Researchers measured the contents of the bags before handing them out, and after the viewing sessions.
“We measured food consumption,” said Prof. Deng. “We didn't just get people's attitudes.”
The findings indicated the transparency of food packaging influences snacking habits in different ways. The response to the clear packaging depended on the size, visual appeal and healthfulness of the food inside.
Participants ate less large, visually appealing snack food (such as cookies) from transparent packages than they did from opaque ones. Small foods like foods like M&Ms fared better in clear packaging; participants ate 58% more of the candies from the clear bags than the opaque.
Healthful foods also were impacted by presentation in clear packs. For example, the baby carrots were munched on less when in clear bags than in opaque.
“The health food results were somewhat surprising to us," Srinivasan said.
The takeaway from the study, according to the researchers: Clear bags increase temptation to eat delicious-looking foods, but they also make it more apparent just how much food you’re about to down. Retailers might be wise to offer small foods in clear packages and large foods and vegetables in opaque packaging.