The taste of the sound or the sound of the taste? How sounding packaging influence food perception

One of the most common multisensory experiences in everyday life is eating. The flavour of a food is defined, in human brain, by a unique combination of taste, aroma, consistency, temperature, sounds and visual aspects. In this context, all the sensory properties of a product, i.e. not just the taste properties, influence our testing experience, as well as our tasting experiences can alter the perception of the other sensory properties. But even if some senses such as sight and taste have been deeply examined in this situation, other senses such as hearing still represents a quite unexplored potential in the current scientific research. The influence of auditory aspects on foods and drinks might take place at different stages of the food experience. In fact, auditory aspects typically considered as primarily perceived when we are consuming food (i.e. prime-coincident sounds such as first bite, or late-coincident sounds such as the mastication sound) have been proved affecting instead the food intake process even since the very first approach to food itself (i.e. anticipatory sounds such as the packaging sound) or after the food intake (i.e. post-prandial sounds such as those produced clearing the table). A first experimental test to explore the relation between consumption sound due to the food packaging and taste-perceived food qualities will be spread in this research presentation, in order to investigate this sound- taste connection, excluding the other senses. The first results of a test conducted on yogurt pots and jars will be presented. Three widely commercialized yogurt pots and jars characterized by a similar cylindrical meta-shape, but differing in materials (glass, clay and polypropylene, respectively) were selected as case studies. Thirty subjects mixed between experts in sensory analysis and naïve took part to the test. Each participant was asked to taste a spoon of yogurt under three different conditions, i.e. taking it from each one of the three packaging. Both the yogurt and the spoon used for the tasting were the same in the three conditions, and the food was submitted always at the same temperature. The test was unfolded in random order and each pot was hidden in a box in order to exclude the visual component. The pots were filled with a standardized little quantity of food, making the subject produce some noise with the spoon to the containers’ sides to collect the yogurt from the pots. Before and after each test, subjects were asked to prepare themselves to the taste by eating a piece of cracker and drinking a sip of water. After each taste, a questionnaire was administrated to the participants, asking them to evaluate on a 1 to 9-points Likert scale the tasted yogurts on the following items: sweetness, sourness, tastiness, thickness, genuineness, calorificness, craftsmanship and expensiveness. Median and interquartile ranges of the collected data were calculated, comparing the test unfolded with each yogurt pot. A first comparison on each attribute obtained with the three pots showed that little but significant differences can be observed in the evaluation of each item in relation with the sound variation. For example, yogurt seems to be perceived as sweeter when contained into the glass jar, rather than into the plastic or clay pots. Furthermore, the product is perceived also as more expensive when it is contained in glass or clay-sounding jars. Finally, clay-sounds seem to positively affect on craftsmanship and genuineness perception. A subsequent global comparison on the results of all the attributes obtained with the three pots confirmed how the sounds produced by spoons rubbing against the different jars affect on food perception by consumers. Finally, it can be assumed that both taste and quality perception can be influenced by packaging sounds. For this reason, several other studies can be hypothesized in future in order to further investigate these or other synaesthesia between sound and taste. The present experimental investigation and methodology shows how specific packaging sounds can affect differently on the overall food product perception. This finding entails cognitive nutrition as a support for designers dealing with the development of food packaging and food products: the methodology supports food stakeholders during the materials choice, the design phase and the product finalising. In fact, designers must be familiar with all available options if they wish to choose the right materials for his product early on in the design process; above all, they must be able to analyse whether or not the materials suit their product. Sound properties of a product (linked with gestures and product shapes, temperature, texture, colour and weight) are one of the invisible aspects of design that were proved being able to change the product perception, as well as to contribute to characterizing the user experience of a product that anticipates the consumers’ desires, involving them in an all-around sensory experience.