ABSTRACT
Consumer science involves the study of consumers' attitudes, expectations 
and knowledge, as well as consumer preference. This is an excellent tool 
use in the product development and to help ensuring the product success in 
the marketplace. Nowadays, one of the main trends in the food industry is to 
contribute to consumers' wellbeing through offering low calorie foods or 
enriched with functional ingredients. In this context, it is necessary to know 
the consumers' necessities and to promote choosing a beneficial diet.  

The main objective of this research was to study how different non-sensory 
and sensory parameters influenced the selection of low calorie or enriched 
food, including the consumers' attitudes, knowledge and behaviour.

First, we studied the main factors underlying consumers' food choice, 
resulting that "sensory appeal", "price" and "convenience" were the most 
important factors underpinning Spaniards' food choice. It was observed that 
specific health-promoting ingredients were not considered important in the 
food choice rank, suggesting a low nutritional knowledge. With this 
background, a nutritional food knowledge questionnaire was applied and 
related with the use of nutritional food labels. The results revealed that the 
nutritional knowledge level was linked with the educational level and with the 
used of nutritional label information. Meaning, the higher the nutritional 
knowledge, the more frequent it would be the use of nutritional labelling in 
food choice related decisions.

The first contact between consumers and the food product is normally the 
packaging and its labelling. Based on this fact, we investigated consumers' 
perception of the package and the expectations raised by nutritional and 
health claims in enriched and calorie reduced biscuits. Results revealed that 
the front part of the package is the most influential and claims too long were 
perceived as a negative characteristic. In addition, it was studied the effect 
of food package information and sensory characteristics on the perception of 
healthiness and the acceptability in the mentioned biscuits. It was observed 
that the sensory characteristics played an important role in the acceptability 
and this fact was decisive to ensure the repurchase. The package 
information could make a product to be perceived as healthier but the 
consumers were not willing to sacrifice taste for health effects. This fact, 
showed how sensory and non-sensory characteristics interact determining 
consumer perceptions. Nevertheless, these interactions depend on each 
product (category, brand familiarity, packaging, formulation, and information 
messages).

In addition, it was studied how consumers' intrinsic characteristics, 
personality and food choices motives, influence the consumption of low 
calorie and enriched food. It was obtained a model that explained that weight 
control, self-esteem, responsibility and emotional instability were the main 
reasons (direct or indirect) for consuming these products. 

Finally, we studied the main factors that involved the functional food 
consumption. Results revealed that positive attitudes and novelty directly 
influenced consumers' consumption. Also, it was observed that health was 
not a decisive factor for the purchase of these products, suggesting that 
consumer would need more information about which food components 
produce a health benefit effect.