Tasteless odours can ‘trick’ senses in reduced salt foods: Study

The food industry is currently working to a mandate of reducing sodium chloride levels in packaged and prepared foods, as part of an effort to curb excessive consumption linked to increase risk of high blood pressure and stroke. The World Health Organization recommends adults consume no more than 5g of salt a day.

This has led to intense R&D on salt replacers and taste enhancers on the part of food ingredients companies, as reducing salt levels can have a negative impact on the sensory properties of products.

A previous study has shown that lightly salted and aromatised water can evoke salty impressions; aromas of sardine or bacon gave a higher impression of saltiness than comté cheese or soy sauce.

The new study, conducted by European Sensory Network scientists at INRA in Dijon, France, and partners in The Netherlands, went a step further, using the aromas in complex foods. They developed a test product with variations of a simple, neutral-flavour mozzarella-like soft cheese with different grades of fat-content and dry matter levels.

They tested the product on a group of 27 French consumers aged 19-61 with no previous experience in sensory analysis, who were asked to grade 16 different cheese samples under two separate conditions using a rating scale of 0-10. Wearing nose clips, they rated the intensity of the four basic taste qualities of sour, salty, bitter, and sweet, and texture (firmness, moistness, and granularity). They also noted their preferences.

In the second stage of the experiment the same procedure was carried out, but without the participants wearing nose clips.

The researchers observed that the products produced differentiated texture perceptions when the nose clips were not worn. Aroma had no impact on the perception of texture but a marked difference was observed in the taste of the models.

In the clip-free tests, the cheese samples with sardine and comté-flavoured products were perceived as saltier than the unflavoured and carrot-flavoured products .

The authors say the effect – called odour-induced saltiness enhancement (OISE) – is particularly marked in high fat models.

Study leader Génica Lawrence explained: “Odour-taste interaction and integration occur at the neural level. This interaction depends on the association between both stimuli. The perceived taste impressions of a food are the results of a variety of sensory signals that are perceived simultaneously and melded in the brain into a general impression. These impressions will be closely linked together in the memory.” ​

“Our study suggests that the measured addition of such aromas could be an effective new strategy for food manufacturers in counterbalancing the sensory shortcomings of salt-reduced foods.” ​

She added that it would be worth investigating whether other aromas associated with sweetness, such as vanilla, could help in the formulation of lower sugar food products in the same way.

Source​

International Dairy Journal

Doi:10.1016/j.idairyj.2010.09.005

Using cross-modal interactions to counterbalance salt reduction in solid foods

Authors: Lawrence G, Salles C, Palicki O, Septier C, Busch J, Danguin TT