Context
Kinder surprise eggs bring back happy memories for many of us. We all participated in the same ritual: seeing the familiar egg-shaped red, blue and white packaging, then shaking it beside our ear to check that the surprise is there, then smelling the chocolate before savoring it. Analyzing this routine from a marketer’s perspective, consumers are first provided with a visual cue (the famous packaging), then an auditive cue (surprise shaking) and an olfactive cue (chocolate smell) before tasting the product, which greatly contributes to enjoying one’s Kinder egg experience. In an article published in 2021 in the Journal of Consumer Psychology, Biswas, Labrecque and Lehmann how such sensory cue sequences impact food evaluation.
Research questions
Previous research shows that sensory cues – such as visuals or smells – have an impact on food evaluation. However, these studies focused on the presence of simultaneous stimuli, neglecting the fact that sensory stimuli are often encountered in a sequence rather than simultaneously. For instance, when people head to the bakery to get bread, chances are they will smell the freshly baked bread from the street before approaching the shop window and seeing the products. In this case, the olfactory cues come before the visual cues. However, when buying a sandwich at the supermarket, consumers see the product through its transparent packaging before smelling it. In this case, the visual cues come before the olfactory cues. Since stimuli can be encountered in different orders when purchasing food products, Biswas, Labrecque and Lehmann aim at answering the following research question: how does the order in which visual and olfactory cues are encountered influence food evaluations?
Method
To answer this research question, the authors devised four experiments to test how the order in which visual and olfactory cues are encountered influence food evaluation. The studies were conducted across three product categories (fruit snack, beverage, cookie). Pre-tests were made to ensure the accuracy and relevance of the cues.
Cue sequence was manipulated in different ways from one study to the other. For instance, in study 1, 198 participants were presented with an opaque envelope containing a fruit snack. Some of the participants were asked to sneak a peak at what was inside the envelope then smell it (visual-olfactory sequence) or open the envelope without looking to smell and then look at the content (olfactory-visual sequence), or smell without looking (olfactory cues only), or look without smelling (visual cues only). In study 2 (conducted on 76 students), the authors imagined a different manipulation of cue sequence. Since the product was a beverage, they opted for transparent vs opaque cups (visual cue manipulation) and spreading a fragrance inside VS outside of the cup lid (olfactory cue manipulation).
Studies 3 and 4 were devised to assess the underlying mechanisms explaining the impact of the cue sequence on food evaluation.
The authors were careful to control that hunger or thirst did not interfere with their experiments.
Results
– The order in which visual and olfactory cues are encountered matters in the food evaluation process. Encountering visual cues before olfactory cues leads to more favorable taste perceptions than encountering olfactory cues before visual cues, encountering visual cues only or encountering olfactory cues only. Moreover, the visual-olfactory cues sequence creates more vivid imagery than other sequences. Finally, the visual-olfactory cues sequence increases volume consumption compared with other sequences.
– This result stems from the fact that olfactory identification is harder than other sensory identifications. The human brain is relatively weak in processing olfactory cues compared to other sensory cues since olfactory detection is slow (about 10 times slower than visual detection) and since there are fewer cells for olfactory images than cells for visual images in the brain. Consequently, olfactory imagery is harder than visual imagery: it is harder to imagine a smell than to imagine an image. Therefore, human olfactory perception is unreliable and benefits from visual cues. In other words, encountering visual cues before olfactory cues allows the brain to benefit from the visual cues and process the olfactory cues more easily. Moreover, olfactory cues matter more than visual cues in influencing taste perceptions. To sum up, taste perception is enhanced in visual-olfactory cue sequences because olfactory cues, which contribute more to taste perception, are better decrypted thanks to visual cues. Put differently, the visual-olfactory cue sequence allows the brain to process cues more easily which enhances taste perception.
– These results hold only in the case of congruent visual cues. Indeed, visual cues are easily processed by the brain and create expectations. When these expectations are confirmed by the olfactory cue (ie when visual cues are congruent with olfactory cues), the visual cues have truly facilitated the olfactory cue identification process. However, when these expectations are neither confirmed nor disconfirmed because the olfactory and the visual cues are incongruent, the visual cues fail to facilitate the olfactory cue identification process (and even make it harder). Since ease of processing is a key variable that allows the success of the visual-olfactory sequence, incongruent visual cues create a cognitive dissonance between expectations and what the consumer is really presented, which will cancel the beneficial effects of the visual-olfactory cue sequence on taste perception.
Why is this article relevant for researchers?
This research reveals the importance of a sequential approach instead of simultaneous approach when analyzing the impact of sensory cues on food evaluation. However, the present article focuses on visual and olfactory cues, which opens avenues for future research on the impact of sequences involving different sensory cues (auditive for example) on product evaluation. The findings could be extended to non-food products. Moreover, the analysis of cue sequence could go beyond stimuli category and differentiate between types of visual stimuli (for example: shop window, packaging, product etc). These results may also provide a foundation for research about consumer health and well-being.
The authors also point out that these results could help contribute to the literature of judgement updating, highlighting the role of congruent stimuli, ease of processing and expectations. Future research could notably explore a potential pioneering advantage of the stimuli that are encountered first. For instance, could a negative visual stimulus negatively impact the following olfactive stimulus?
Why is this article relevant for professionals?
The present findings are applicable both to retail design and product design. It can entice producers to distribute food products in transparent containers or to display images of the product on the box, so that consumers encounter visual cues before olfactive cues, which will in turn improve perceived tastiness and consumption volume. For instance, these Buitoni pizza boxes all display appetizing images of the product. In the same vein, this article provides insight in the raging battle opposing Coca Cola bottles VS cans : while many argue that there are several factors that may affect the differential taste between Cocal Cola bottles and cans, this article may add a “psychological” dimension to the problem, by showing that perceived tastiness should be higher for bottled Coca Cola than canned Coca Cola, since bottles allow a visual-olfactory cue sequence.
This research provides ways to improve strategies based on scent marketing. For instance, a popular practice for bakeries is to spread a bakery scent outside the shop, so that the consumer is attracted by the smell. Though this strategy may be successful in terms of attraction in the short run, it may negatively affect perceived tastiness in the long run. Therefore, this article invites bakeries to weigh the benefits and costs of their scent marketing strategies, and maybe try to expose consumers to visual cues before olfactory cues, so that they benefit from both the sensory cue sequence and the scent marketing effects.
More generally, since this paper highlights the importance of ease of processing in product evaluation, marketers should endeavor to confront consumers with congruent and unambiguous sensory cues, including all 5 senses, that create reasonable intentions from consumers towards the product. As an example, Vindigo wine (blue wine) did not receive a warm welcome in France, since the colors usually associated with wine are white, red or rosé.