Researchers at HSE University in Perm have used electroencephalography (EEG) to determine that consumers are willing to pay 10% more for chocolate when they know it to be a premium product. On the other hand, if consumers are aware that a chocolate product is inexpensive, their willingness to pay decreases by 13%. On average, men are willing to pay 8.8 monetary units more for chocolate than women, and men's willingness to pay decreases by 0.3 monetary units with each additional year of age. The study has been published in Food Quality and Preference.
According to 2021 data, Russians eat an average of 39 kilograms of sugar per year, including confectionery, jams and canned fruit and berries. Chocolate bars are the favourite treat of those with a sweet tooth—they are preferred by one in three Russians.
The WTP (willingness to pay) indicator is used to assess purchasing power, which represents the maximum amount that a buyer is willing to pay for a product. Marketers use surveys, focus groups and interviews to determine WTP, but this approach can be expensive, time-consuming, and does not always provide an accurate representation of respondents' preferences.
To obtain a more objective assessment of willingness to pay, HSE University-Perm researchers Daria Semenova, Sofia Kulikova, Yulia Zaripova (Shamgunova) and Mariia Molodchik used electroencephalography to measure neurophysiological brain reactions to chocolate tasting.
The study involved 24 volunteers (13 men and 11 women) between the ages of 19 and 61 who tasted five different brands of dark chocolate. These included a little-known inexpensive brand, a well-known brand in the medium price range, a premium brand, a 'healthy' brand made with fructose instead of sugar, and an organic, carob-based brand without cocoa.
The experiment was conducted in two stages. During the first ('blind') stage, the participants tasted the five types of chocolate in a random order without knowing which brand they were tasting. After the tasting, they were asked to rate the taste of the chocolate on a five-point scale, indicate their willingness to pay for each chocolate, and try to guess the retail price of each one. In the second ('informed') stage, before tasting the same types of chocolate again, the participants were shown each packaging along with information about the brand and the product ingredients.
The researchers recorded the subjects' EEG signals in the prefrontal, frontal, parietal, and occipital regions of the brain during both stages. The data on brain activity was processed using spectral analysis.
The analysis found that the encoding of WTP was associated with activity in the frontal regions of the brain, which is consistent with previous research on the topic. The strongest association between WTP and neurophysiological brain wave indicators occurred in the prefrontal and frontal regions at frequencies of 15–30 Hz (in the beta range). The researchers explained that activity in the frontal lobes is responsible for high-level cognitive processes, including the decision-making process that determines how much a person would be willing to pay.
On average, men were willing to pay 8.8 monetary units more for chocolate than women, and men's willingness to pay decreased by 0.3 monetary units with each additional year of age.
The researchers also observed a difference in consumer behaviour between the 'blind' and 'informed' tasting experiments. In the blind tasting, the participants' willingness to purchase chocolate was associated with the taste. The highest scores were given to the medium-priced chocolate (3.9 out of 5), the premium chocolate (3.74) and the inexpensive chocolate (3.62). During the informed tasting, the participants showed a willingness to pay 3% more for the well-known chocolate from the middle segment and 9.9% more for the expensive premium chocolate.
As for the other brands, the participants' WTP decreased by 1% for the 'healthy' chocolate and by 13.25% for the inexpensive product compared to their initial blind tasting score. The greatest decrease in willingness to pay—by 16%—was for the organic chocolate without cocoa. The researchers attribute this effect to packaging.
We compared the data from the blind and informed experiments and found that packaging can create expectations and influence the willingness to pay for chocolate, which can be detected by analysing EEG signals. In fact, well-known packaging increases the willingness to pay, while less known packaging reduces it.
The authors believe that collecting more data on brain activity during consumer decision-making will advance the field of neuromarketing, and they hope that future studies will build upon their findings.
Our objective is to enhance the classical model of consumer behaviour by integrating explicit and implicit measurements to better predict WTP. This study broadens the understanding of willingness to pay by incorporating both taste scores and EEG-based measurements. This approach can be applied in future research into consumer food preferences.
Senior Research Fellow, Centre for Cognitive Neuroscience, HSE Campus in Perm
Junior Research Fellow, Centre for Cognitive Neuroscience, HSE University in Perm