# Aromachology Related to Foods, Scientific Lines of Evidence: A Review
## 3 Results and Discussion
### Revision of Scientific Literature
[PERSON] and [PERSON] [39], in the context of a field experiment, varied the aroma along with the retail density (how crowded the mall was) and examined the perceptions of the buyers about the quality of the product, mall environment, and positive effect. They found a positive effect of ambient scent on shoppers' perceptions of the mall's atmosphere only at the medium retail density level. In addition, a favourable perception of the retail environment influenced the perception of product quality. Buyers' moods did not have a significant direct effect on perceptions of product quality. _What data were collected in the experiments?_ At present, almost 50 per cent of aroma-chology studies on food are based on subjective assessments collected under controlled conditions (questionnaires), and there is little evidence on the real effect of aromatisation on physiological responses and behaviour. Very little use of neuroscience tools has been reported so far in the scientific literature [28], and the measurement of physiological data is very limited [27]. Studies reviewed are a collection of individual contributions with scarce coincidences on methodology, and therefore, collected results are quite difficult to compare. Given the diversity of methods employed and parameters evaluated such studies cannot be compared or discussed as a whole. Another relevant point is that most studies are directed to evaluate food choices or appetite. The aims of scent use are not always directed only to enhance customer satisfaction, as in non-food stores, but mainly to modulate food consumption or to provide knowledge on understanding the effect of odour on consumer mood or behaviour. Given that the scent can modulate consumer behaviour, many types of studies with different purposes may be planned and may need different methodology and measured parameters. _Where did the studies take place?_ Most of the studies were conducted under artificial laboratory conditions (79%) mainly collecting data by computer-based assessments, and only three were conducted in real conditions with real customers (restaurant, store) (details in Table S1). _What were the most tested scents?_ Fruit scents were the most popular in the reviewed studies. The scents used in the scientific studies were grouped as follows into five distinct groups: sweets, fruits, salty, floral, and spices. Among the aroma groups used, the most commonly used were 'fruits' (31.4%), and 'floral' (29.4%), followed by'salty' (17.6%),'sweet' (15.7%), and'spices' (5.9%) (details in Table S2). Flowers were tested in studies evaluating congruent aromas [30]. _What were the main findings of the reviewed studies?_ Table 1 presents findings from individual studies that are summarised in this section. The use of pleasant scents enhanced pleasantness, and unpleasant odours raised stronger emotions than pleasant ones [28]. The use of ambient scents modified behaviour (time spent at stores or viewing food images) [22; 23; 25]. The presence of scent in general stores can slow the flow of customers in the store and therefore increase the time spent in the store [2]. Scenting affected consumer choices, and the effect of scents was enhanced by the congruency of the odour with the images, products, or even seasons [23; 29; 30; 32; 35]. Scents, hence olfactory perceptions, interact with visual perceptions or imagery [27; 33]. Appetite was affected by odour exposure; however, nonconclusive results can be obtained from the reviewed studies. [PERSON] [29] reported that exposure to chocolate scent reduced the perceived hunger, and other pleasant scents (baby powder) also reduced hunger perception. Some authors reported that exposure to food odours increases the appetite for congruent foods, including sweets, [34; 35] and that fresh scents reduced the craving for sweets. Some authors even concluded that exposure to food odours may promote overeating and therefore contribute to obesity [35].