Giuseppina Gifuni

Background/Objectives: Ambient sensory cues can influence food choice, yet their role in everyday environments remains underexplored, with much of the existing evidence derived from laboratory studies. This is particularly relevant in university settings, where students often make rapid, convenience-driven choices that may be nudged toward healthier options by sensory cues (e.g., images or scents). Methods: A quasi-experimental field study was conducted across three consecutive one-week conditions: control, visual (a nature-themed poster), and olfactory (jasmine fragrance). Snacks were classified according to perceived healthiness ratings from a pre-study questionnaire. After predefined exclusions, purchases were analyzed using binary logistic regression, with condition as the main predictor and price and time of day examined as additional factors. Results: Among N = 1043 purchases, products classified as healthy were more frequent during the olfactory week than during the control and visual weeks. The visual condition did not differ significantly from control. Higher prices were associated with lower odds of purchasing a product classified as healthy, whereas time of day was not significantly associated with purchasing behavior. Conclusions: These findings provide field-based evidence suggesting that olfactory cues may be associated with a shift toward food choices perceived as healthier in vending-machine environments, pointing to their potential as a low-cost sensory nudging strategy while highlighting the need for confirmation through randomized or counterbalanced designs and replication across diverse real-world food-choice settings beyond university contexts.

The reuse of by-products from plant processing as feed for animals aligns with the principles of a circular economy. Feeding dairy ruminants agro-industrial by-products often alters the chemical composition and sensory characteristics of dairy items. A dual approach—classic with neuro-sensory techniques—was utilized to evaluate the effect of prickly pear by-products on the diets of dairy ewes. Fresh Pecorino cheeses made from the milk of two groups of sheep fed with and without prickly pear by-product silage were analyzed for chemical composition and volatile organic compounds (VOCs). Furthermore, a neurosensory approach with consumers was used, combining electroencephalography (EEG) and temporal dominance of sensations techniques (TDS). Prickly pear silage in sheep diets did not alter the chemical composition of fresh cheese, but it did modify its fatty acids, with a significant increase in SFA (+2.60%) and PUFA (+0.33%), with a better n-6/n-3 ratio (−0.35%) due to higher omega-3 fatty acid content (+0.23%). The identification of VOCs revealed an increase in caproic acid (+27.27%) and n-caprylic acid (+6.47%) and a greater presence of sweet notes in the prickly pear-based cheeses, which exhibited a different aromatic complexity compared with the control cheeses. Even with a neuromarketing approach, sweetness remained the predominant sensation.

Nudge has proven effective in promoting healthier eating, especially in academic environments. However, its application in vending machines has not been extensively studied yet, with existing studies focusing on choice and overlooking the emotional and cognitive responses to these interventions. Our research explored how visual and olfactory nudges (and a combination of both) can encourage healthier choices in university vending machines, and examined the related emotional and cognitive reactions, adopting a consumer neuroscience approach. It encompassed three distinct analysis levels: behavioral (snack choice), neurophysiological (emotional and cognitive reactions assessed through skin conductance and electroencephalography), and attentional (visual attention on snacks evaluated via eye-tracking). The findings revealed that while visual and olfactory nudges, when considered individually, were associated with an increased likelihood of making healthier choices, their combined effect was not significant. Skin conductance indicated that olfactory and combined nudge interventions induced relaxation, potentially promoting healthier choices. Electroencephalography results suggested a reduced motivational approach toward snacks when both nudges were combined. Eye-tracking indicated that individuals pay heightened attention to healthy snacks when positioned at eye level, however, this can also be affected by the nudge condition. Our findings suggest that implementing visual or olfactory nudges alone may promote healthier choices in vending machines, whereas combining them may lessen their impact, and corroborate the importance of positioning target products in locations where they are readily visible to consumers. These insights enhance our understanding of the emotional, cognitive, and attentional components behind nudge interventions and offer practical strategies for promoting healthier eating habits.