Salty odours may improve the salty taste intensity and consumer acceptance of low salt foods by increasing the perception of salty flavours, according to new research from Unilever.
The study, published in International Dairy Journal and led by Génica Lawrence from the University of Burgundy, France, suggested that odour-induced saltiness enhancement (OISE) could increase the salt flavour and taste intensity in food products, thus meaning that actual salt levels can be reduced without impacting taste or consumer preference.
“Alone or in combination with other strategies developed to compensate salt reduction, OISE could be a very interesting strategy to enhance salt perception in food with reduced salt content,” said the researchers.
“Our results showed that salt-associated odours (e.g, comté cheese and sardine) can enhance saltiness in complex solid-food matrices containing a low amount of salt,” they added.
The researchers said that their study’s data also suggests that congruence between an odour and food product is not a determinant factor for OISE.
“We found that OISE was not more pronounced with congruent odours: sardine odour, which was less congruent than comté-cheese odour, tended to induce more saltiness enhancement,” they said.
Excess dietary sodium intake has been linked to the development of hypertension, cardiovascular disease and other health problems. Because of this, reducing the sodium content in food products has become a major issue for the processed-food sector.
The authors noted that extensive research on low-salt food has been necessary, since sodium chloride has a number of technical functions in foods – including preservation, water and fat binding and an important role in flavour enhancement.
Lawrence and colleagues said one of the main consequences of decreasing salt content is the alteration of sensory characteristics, which can often be associated with a decrease in consumer acceptance.
They said that one recently proposed reduction strategy uses tasteless odorants to compensate for salt reduction through odour-taste (or ‘smell taste’) interactions.
Previous studies have shown that salt-associated odours can enhance saltiness in solutions containing a low level of sodium chloride. However, until now odour-taste interaction studies have mainly investigated interactions in solutions – with few investigating such perceptual interactions in real food products.
“Although it appears to be clear that food-matrix structure and perceived texture can impact the release and perception of odorants and tastants, it remains poorly investigated whether indirect interactions could take place during food consumption,” said the researchers.
The new study assessed the efficiency of OISE as a strategy to compensate for salt reduction in solid food, especially taking into account texture variation and the influence of cross-modal aroma-texture-taste interactions on saltiness perception.
Four model cheeses, of varying texture, were produced and flavoured with three commercial tasteless aromas (comté cheese, sardine, and carrot) which have been found to enhance or to decrease saltiness by previous research.
The researchers reported that the perceived saltiness in both flavoured and unflavoured model cheeses – with identical salt contents – revealed a significant saltiness enhancement induced by the comté cheese and sardine odours.
They reported that the carrot odour, which is not associated with saltiness, did not enhance saltiness perception – but in-fact reduced the perception of salt flavour in the model cheeses.
Differences in saltiness perception were also observed between the comté cheese and sardine odours.
“Although the comté-cheese odour seemed to be more congruent with the cheese products, we found the saltiness score to be higher when the odour was sardine-like,” said the researchers.
“These findings revealed that well-selected aromas could enhance saltiness in low-salt-content solid-food products of various textures,” they added.
They said that if proved successful, the strategy it could also be attempted for other tastants or food ingredients (such as sugar or fat) which have a negative impact on health at high levels but play an important role in food functional properties and have an important sensory impact on food pleasantness and acceptability.
Source: International Dairy Journal
Volume 21, Issue 2, Pages 103-110, doi: 10.1016/j.idairyj.2010.09.005
“Using cross-modal interactions to counterbalance salt reduction in solid foods”
Authors: G. Lawrence, C. Salles, O. Palicki, C. Septier, J. Busch, T. Thomas-Danguin