The authors, from Penn State University and the University of Connecticut, found that different perception of saltiness is linked to a genetically determined variation in taste function. They said that ‘supertasters’ – those with a higher number of papillae (the bumps on the tongue that are surrounded by taste buds) – were more likely to enjoy high-sodium foods than nontasters – those with the lowest number of papillae. This could be because salt plays a role in blocking unpleasant flavors, which may be more obvious to a supertaster.
Lead researcher and assistant professor of food science at Penn State University John Hayes said: "For example, cheese is a wonderful blend of dairy flavors from fermented milk, but also bitter tastes from ripening that are blocked by salt. A supertaster finds low-salt cheese unpleasant because the bitterness is too pronounced."
This could have important implications for the food industry in its quest to produce low-sodium foods that still have an acceptable flavor for consumers. One approach to producing foods with lower sodium levels has been to gradually reduce the amount of sodium to give consumers’ tastes time to adapt. However, the research suggests that for supertasters, it could be more difficult to like some reduced sodium products.
On the other hand, supertasters may be less likely to add salt to products, the researchers found.
"Interestingly, nontasters may be more likely to add salt to foods at the table because they need more salt to reach the same level of perceived saltiness as a supertaster," Hayes said. "However, most of the salt we consume comes from salt added to processed foods and not from the salt shaker."
It is estimated that around 75 percent of the sodium in the average American diet comes from packaged foods, so supertasters tend to eat more sodium overall, Hayes said.
"Some individuals eat more salt, both because they like the taste of saltiness more and also because it is needed to block other unpleasant tastes in food,” he said. “Supertasters, people who experience tastes more intensely, consume more salt than do nontasters. Snack foods have saltiness as their primary flavor, and at least for these foods, more is better, so the supertasters seem to like them more."
The researchers examined the sodium intake and taste preferences of 87 non-smoking adults, asking them to taste and rate how much they liked samples of soy sauce, cheddar, pretzels and potato chips, in regular and low-sodium variants. They also rated their liking of 38 different foods, some of which were high in sodium, using a recognized scientific scale.
Industry has been under increasing pressure to reduce sodium, as health experts have said most Americans consume far too much. According to the Centers for Disease Control and Prevention, the average is about 3,400mg a day, compared to the maximum recommended intake of 2,300mg.
Source: Behavior and Physiology
doi:10.1016/j.physbeh.2010.03.017 pp. 369-380
“Explaining variability in sodium intake through oral sensory phenotype, salt sensation and liking"
Authors: John Hayes, Bridget Sullivan, Valerie Duffy