Expanding the Scope of Sensory Analysis

Massey University sensory science professor Joanne Hort has been thinking about the way emotions affect an individual’s response to food since she was a graduate student more than two decades ago.

During her doctoral work at Sheffield Hallam University in the United Kingdom, Hort was part of a project that assessed consumers’ sensory responses to a popular brand of black currant cordial. In that project, the researchers found that while various samples were liked by tasters in equal measure, they had different emotional responses to some. Several of the beverages weren’t trusted, Hort says, and it turned out that, unbeknownst to the tasters, those were the ones containing artificial sweeteners. The artificial taste triggered an emotional response of distrust.

“We started to see pathways as to why these emotional responses were occurring,” says Hort. “That’s when I really started to understand that this was going to be really important for sensory consumer scientists.”

At New Zealand–based Massey University, Hort heads the Food Experience and Sensory Testing Laboratory (Feast), which is exploring novel methods to broaden sensory science and gain a better understanding of our relationship to foods by measuring the emotions they evoke.

“My main goal is to try and understand the key drivers that can influence food choice behavior and how we can therefore make life better for people in general,” says Hort, a professor in the university’s School of Food Technology and Natural Sciences and the Fonterra-Riddet chair of Consumer and Sensory Science there.

Conventional liking measures have their place, but they don’t capture the full experience of food because liking and emotional responses are different brain activities, and capturing both necessitates different measurements, Hort continues.

“Liking is still important, but it’s very immediate, whereas we’re wired to use our emotional response to make decisions,” she explains. “Emotional response becomes much more important when we’re thinking about food choice behaviors.”

Hort’s research has covered plant-based meat substitutes, beer, wine, and snacks, among other foods. Before joining Massey in 2017, she was the SABMiller chair of Sensory Science at the University of Nottingham in the United Kingdom. Her current chair is funded by New Zealand dairy cooperative Fonterra. The organization’s leadership, Hort says, knows the importance of sensory science in helping them better understand consumers.

Immersive Eating

Where, when, and how people eat has a strong impact on their feelings about food, Hort explains. Yet sensory booths remain the standard testing environment—even though they’re far removed from how and where people really eat.

The Feast lab has a digital immersive sensory room—the only one in New Zealand used for sensory science—where researchers can simulate different environments. They can turn the room into a café, for example, with 3-D video—the hissing of an espresso machine, the smell of a latte, and the customers’ chatter. The sounds come from video or can be added using a computer, and the aromas come from “Stinkifiers”—instruments the researchers developed that releases aromas. Creating such an environment allows the researchers to prompt a reaction while a taster is eating or drinking and capture that response in real time.

Hort’s research comparing tasting panel results using sensory booths, digital environments like Feast’s immersive room, and real-world environments found that the digital spaces and the real world elicited similar responses, which differed from the sensory booth findings. However, sensory booth testing is still important, she points out, because it allows more control compared to the real world.

Hort is also investigating physiological responses to food and using technologies to measure them. Heart rate, sweat, facial expression, and pupil dilation, for example, can be measured while a taster is eating a food product. Although these approaches are in the early stages, Hort says that they’re already providing valuable information.

“We can see differences in these physiological responses across products,” she says, while also cautioning that these techniques must be used thoughtfully and ethically. “We’ve got to think carefully about these physiological technologies and how we use them and for what purpose,” she says.

Feast researchers are also trialing response time tests. While tasters are sampling a product, they’re shown a list of emotions on a screen. They have a maximum of three seconds to click yes if they judge a word relevant and no if they don’t.

Hort explains that the researchers are interested in the amount of time it takes the taster to press the key. Their recent research on two yogurt products found that the tasters selected some emotions for one yogurt that they didn’t for the other, even though the two were liked equally.

“That’s a more implicit way of collecting the data where the participants don’t have that much time to think about it,” says Hort. “We’re trying to get to the true responses, but this really is in development.”

Jenna Fryer, who graduated from Oregon State University this spring with a PhD in food science and technology, worked with Hort during an internship at Feast and is coauthor of a paper measuring consumer responses to smoke-tainted wine. “Her work is pivotal to the sensory community because it’s really trying to fill in some of the gaps that we have in the understanding of consumer behavior,” Fryer says.

Better Food With Emotions

Dave Lundahl, CEO of behavioral research company InsightsNow, and author of the 2011 book Breakthrough Food Product Innovation Through Emotions Research, says measuring emotions is complex. So while there’s a lot of interest in measuring emotional impacts of a product experience, emotional response testing is not always used during food product development.

Food companies use liking as part of their assessments as to whether a product is ready to go to market or to be further developed, and it’s a relatively easy concept to grasp. “Emotional scores are more difficult for people to understand,” Lundahl says.

Yet maximizing liking—by increasing fats, salt, and sugars—has led to the development of hyperpalatable foods, and that’s “underlying the obesity epidemic,” he continues.

He thinks that using emotional reactions alongside liking will help companies take a new approach to product development. “It creates new ways in which we can introduce healthier foods that are not necessarily maximizing liking,” he says. “But it could be very acceptable and be something that will drive new behaviors so that people can lead healthier lives.”

Ultimately, that might be healthier lives both on Earth and beyond it: Hort’s moonshot idea is using sensory science to help space travelers eat better. Space changes astronauts’ ability to smell and taste. There are also strict guidelines as to what foods can be brought aboard spacecraft and in what form.

“There’s a big concern about how much astronauts can actually consume because they don’t consume enough product,” says Hort. “They’re not getting the nutrition that they need.”

But whether in space or back on Earth, people need to be fed, Hort says, and examining emotional responses is necessary to refining food development. She thinks that understanding consumers better will lead to healthier choices, more environmentally sustainable foods, and less food waste.

“Sensory consumer science has a lot that it can contribute to society and its future progress,” she reflects.ft