Claire Sulmont-Rossé

Impact of a non-attentively perceived odour on subsequent food choices.

Current research in psychology suggests that unconscious processes influence a significant proportion of choices and decisions. To study the impact of a non-attentively perceived odour on food choices, we used a priming paradigm. We had previously shown that non-attentively perceived fruity odours could impact food choice intentions (on a menu card), guiding participants toward items containing more fruit and/or vegetables. The present study was designed to extend these findings, in a real-life consumption setting. One hundred and fifteen participants took part in this study, and were assigned randomly to either a control or a scented condition. On arrival in the laboratory, they were seated in a waiting room. For the scented condition, they were unobtrusively exposed to a pear odour, while under the control condition the waiting room was non-odorised. Following this waiting period, all participants moved into a non-odorised test room where they were asked to choose, from dishes served buffet-style, the starter, main course and dessert that they would actually eat for lunch. The results showed that participants subjected to the scented condition chose to consume the fruity dessert (compote) more frequently than those who had waited under the control condition, who chose more frequently the dessert without fruit (brownie). In line with the findings of our previous study, these results confirm the idea of priming effects specific to the food cue. To conclude, a non-attentively perceived fruity odour was shown to influence actual food choices, guiding individuals towards more fruity desserts. The involvement of implicit processes in food choices should be taken into account in guidelines and strategies designed to promote healthy eating.

True and False Recognition Memories of Odors Induce Distinct Neural Signatures

Neural bases of human olfactory memory are poorly understood. Very few studies have examined neural substrates associated with correct odor recognition, and none has tackled neural networks associated with incorrect odor recognition. We investigated the neural basis of task performance during a yes–no odor recognition memory paradigm in young and elderly subjects using event-related functional magnetic resonance imaging. We explored four response categories: correct (Hit) and incorrect false alarm (FA) recognition, as well as correct (CR) and incorrect (Miss) rejection, and we characterized corresponding brain responses using multivariate analysis and linear regression analysis. We hypothesized that areas of the medial temporal lobe were differentially involved depending on the accuracy of odor recognition. In young adults, we found that significant activity in the hippocampus and the parahippocampal gyrus was associated with correct (true) recognition of odors, whereas the perirhinal cortex was associated with FAs and Misses. These findings are consistent with literature regarding hypothetical functional organization for memory processing. We also found that for correct recognition and rejection responses, the involvement of the hippocampus decreased when memory performances improved. In contrast to young individuals, elderly subjects were more prone to false memories and exhibited less specific activation patterns for the four response categories. Activation in the hippocampus and the parahippocampal gyrus was positively correlated with response bias scores for true and false recognition, demonstrating that conservative subjects produced an additional search effort leading to more activation of these two medial temporal lobe regions. These findings demonstrate that correct and incorrect recognition and rejection induce distinct neural signatures.

Evidence for Different Patterns of Chemosensory Alterations in the Elderly Population: Impact of Age Versus Dependency

The present experiment aimed to explore the interindividual variability in chemosensory abilities among the elderly population. The chemosensory abilities of 559 subjects, aged from 65 to 99 years, were evaluated. Various categories of the elderly, including people who were living at home either without or with assistance, and people who were living in a nursing home, were interviewed. The results revealed that 43% of the sample presented well-preserved chemosensory abilities, whereas 21% of the participants presented a moderate impairment. Of the sample, 33% presented well-preserved olfactory abilities but strong impairment in gustatory abilities and 3% were nearly anosmic but remained able to perceive the salty taste, demonstrating that gustation and olfaction were not systematically damaged simultaneously. The results showed a link between the level of dependence (free living vs. living at home with help vs. nursing home) and chemosensory abilities, independently of the age effect. These results strengthen the hypothesis that the impairment of chemosensory abilities is not only an effect of age per se; rather, it is related to events that are associated with aging. Factors that lead to increased dependence (such as poor health) also lead to an impairment in chemosensory performance.

Improving meal context in nursing homes. Impact of four strategies on food intake and meal pleasure

In France, in most nursing homes, the composition of menus, the time and the place at which meals are served, the choice of ones place at the table are imposed on residents. Yet, the act of eating cannot be restricted to nutritional and sensory aspects alone. It also includes a psycho-affective dimension, which relates to the context in which the meal is served. We tested the impact of four contextual factors, considered individually, on food intake and meal pleasure in elderly people living in nursing homes: the way the main course was named on the menu, the size and the variety of portions of vegetables served to residents, the presence or not of condiments in the middle of the table and the presence or not of elements to modify the surroundings such as a decorative object on the table or background music. Twelve experimental meals were served to 42 nursing home residents. For each factor, we compared a control condition with two experimental conditions. Our study showed that changing a single contextual element of the meal in nursing homes could be sufficient to improve residents satisfaction with their meals and increase the quantities of meat or vegetables consumed, as long as this factor had a direct impact on what was going to be consumed (increased variety on the plate, condiments on the table). Factors affecting the context of the meal (names of dishes, decor) proved to be ineffective. Given the budgetary constraints faced by nursing homes, this study proposes interesting and inexpensive ideas to increase satisfaction with meals and food intake in elderly people who are dependent on others for their meals.

Providing choice and/or variety during a meal: Impact on vegetable liking and intake

Out-of-home catering services frequently offer consumers the opportunity to choose their foods from among different proposals and/or provide consumers with a variety of food. The aim of the present study was to assess the impact of choice and/or variety on food liking and food intake. Fifty-nine normal-weight adults were recruited under the condition that they equally liked three vegetable recipes (green beans with butter, zucchinis with olive oil, spinach with cream). Volunteers participated in four sessions at lunch time. In the no-choice/no-variety condition, volunteers were served one dish randomly selected from among the three. In the no-choice/variety condition, volunteers were served all three dishes. In the choice/no-variety condition, participants chose one dish from among the three dishes. In the choice/variety condition, volunteers chose as many dishes as they desired from among the three dishes. Results showed that providing choice increased vegetable liking and vegetable intake, while offering a variety of vegetables only increased their liking. No synergy effect between choice and variety was observed on vegetable liking and vegetable intake (i.e. the effect in the choice/variety condition was not significantly higher than the effects in no-choice/variety and the choice/no-variety conditions).

The structure of a food product assortment modulates the effect of providing choice on food intake

Several authors showed that providing choice may increase food liking and food intake. However, the impact of choice may be modulated by assortments characteristics, such as the number of alternatives or their dissimilarity. The present study compared the impact of choice on food liking and intake under the two following conditions: (1) when choosing a product to consume from among similar products versus dissimilar products; and (2) when choosing a product to consume from among pleasant products versus unpleasant products. Two experiments were carried out using the same design: the apple puree experiment (nxa0=xa080), where the volunteers choose from among similar products (apple purees varying in texture) and the dessert experiment (nxa0=xa080), where the volunteers choose from among dissimilar products (fruit dessert, dairy dessert, custard, pudding). During the first session, participants rated their liking for 12 products (apples purees or desserts). Then the participants were divided into a pleasant group (nxa0=xa040) in which volunteers were assigned three pleasant products, and an unpleasant group (nxa0=xa040) in which volunteers were assigned three unpleasant products. Finally, all of the volunteers participated in a choice session - volunteers were presented with their three assigned products and asked to choose one of the products, and a no-choice session - volunteers were served with one product that was randomly selected from among their three assigned products. Providing choice led to an increase in food liking in both experiments and an increase in food intake only for the desserts, namely only when the volunteers chose the product to consume from among not too similar alternatives. No effect of assortments pleasantness was observed.

Improving Food Sensory Quality With and For Elderly Consumers

Abstract Within the context of an aging population, developing products that meet the specific needs of seniors while satisfying their sensory and hedonic expectations becomes a major challenge for the food industry as well as for society. In this chapter, we will describe a methodology following the reverse engineering principle that we have used to improve the sensory quality of food according to the sensory expectations and preferences of elderly people. On the basis of this case study and the literature, we will provide some practical recommendations for anyone wishing to carry out consumer tests with the elderly as well as guidance related to the development of food products while taking into account the specificities of the elderly population.

Impact of blade tenderization, marinade and cooking temperature on oral comfort when eating meat in an elderly population

Several studies demonstrated that oral health impairment, such as tooth loss or a decrease in salivary flow might lead elderly people to reduce their meat intake. The present study assessed the impact of culinary processes liable to improve meat texture and smooth down meat oral processing, in order to fulfil the oral capacities of elderly people. Four culinary processes were selected: cooking bag, blade tenderizer, marinade and low-temperature cooking. A panel of 40 elderly participants with good and poor dental status were asked to assess 5 chicken breast samples, 5 roast beef samples and 4 beefsteak samples prepared according to different process conditions by using an oral comfort questionnaire. Results highlighted the fact that oral impairment may alter food bolus formation as well as texture perception while eating meat in elderly people. Furthermore, they revealed that easy-to-do culinary processes may improve meat tenderness and juiciness as well as smooth down food bolus formation, in particular for the roast beef.