Nutritional guidelines defining the appropriate levels of salt, sugar and fat in the diet are well-established. The current task for health professionals and food manufacturers is to help consumers comply with the guidelines. Campaigns like 5-a-day to encourage fruit and vegetable intake are well-known and have been complemented by attempts to reformulate foods so they contain less fat, sugar or salt. In some cases, this latter approach has been very successful as evidenced by the popularity of skim milk and low fat spreads. However, in many other food products, decreasing the levels of fat, sugar and salt in food products adversely affects the sensory attributes and therefore their acceptance by the consumer. It has proved difficult to address this problem by substitution (e.g. fat substitutes) as sugar, salt and fat affect a variety of attributes (e.g. mouth feel, texture and flavour release) so several substitutes may be needed. It is pertinent to ask why we find the changed flavour of these foods unpleasant and why we cannot "learn to like" them, given their nutritional benefits.
One recent concept is that a food product that we enjoy and like, gives us an "emotional reward" when eaten. There is some evidence that emotional reward is ultimately characterised by the release of serotonin in the brain. If we change the formulation of the product, we may leave out a "trigger" stimulus that either activates the emotional response itself or, more likely, is part of a pattern of stimuli that creates the emotional reward. If we consider the popularity of skim milk, and the fact that many skim milk users now find full fat milk distasteful, we can postulate that consumers have trained themselves to like skim milk and therefore have created an emotional reward from a different set of stimuli. Applying this concept to low fat spreads, we find they have an acceptable but different flavour from butter but they deliver two additional advantages: they spread straight from the fridge and they are healthier products than butter. In this example, the emotional reward pattern includes flavour, appearance and ease-in-use components.
Although the sensory properties of a product are key determinants for consumer acceptance, it is clear from the example above that other factors can also be important, such as nutritional quality, type of ingredients, manufacturing process, convenience, ethical issues etc. The hypothesis is that, for some products, the consumer will be willing to accept the reduced sensorial quality that can result from fat or salt reduction, in return for some other "reward". With continued exposure to such products (and a campaign of positive marketing), it is feasible that the consumer would then ‘learn’ to like, and indeed prefer, the sensory profile of such products, in much the same way as semi skimmed milk and alternatives to butter have succeeded.
The proposal for this study is to test the above hypotheses before presenting it to industry as the potential basis for designing foods with improved nutritional properties and acceptable properties in terms of flavour, appearance and "healthy eating". A real food product e.g. pasta sauce (with reduced fat and salt formulations) will be used to identify the important ‘rewards’ or ‘attributes’ associated with this product and their related ‘consequences’ and ‘values’. The key sensory attributes (e.g. colour, taste, aroma, texture) that drive sensory liking will also be identified. To demonstrate the relative importance of the identified attributes, we then intend to develop an experimental market scenario to identify the optimum combination of product attributes that would encourage the consumer to regularly purchase healthier versions of this product category. Finally a pilot exposure study would be conducted to determine if repeated exposure induces increased familiarity and acceptability to the product.