Keeping the taste, reducing the salt

Humans naturally like and even crave the taste of salt. It makes food taste better and adds flavor intensity. It’s necessary for survival, and we’re hard-wired to want it. But people in the U.S. consume significantly more salt every day than is necessary or even healthy.

A round tray filled with glass beakers filled with liquid. This sits under some science-y equipment and is hooked to a big computer. A drawing of an oversized cartoon tongue is on the wall in the background.
WSU’s electronic tongue, which can evaluate taste in food and drinks without getting tired.

According to the U.S. Office of Disease Prevention and Health Promotion, the recommended maximum amount of salt consumed per day is less than 2,300 mg. The average American adult female consumes 2,980 mg per day, while males average over 4,000 mg per day.

Overconsumption of salt can lead to negative health outcomes, such as hypertension, or high blood pressure, in children and adults. That’s why WSU researchers are looking at ways to reduce sodium chloride, the salt we crave and need, in food without altering how tasty it is.

“It isn’t surprising that it’s really hard to replace salt,” said Carolyn Ross, a professor in the WSU/UI School of Food Science.

Salt is one of the five basic tastes that humans have, along with sweet, sour, bitter, and umami, or savory taste. Salt also enhances sweetness and can mask bitter or metallic tastes in foods.

In a paper published in the February issue of the Journal of Food Science, Ross and colleagues looked at salt blends that use less sodium chloride and include other salts like calcium chloride and potassium chloride. Both of those salts have no adverse health effects on people, Ross said. Potassium can actually help reduce blood pressure. Unfortunately, they aren’t very tasty.

Scientist sliding a wine and survey through a window.
Dr. Carolyn Ross  in the WSU Sensory Laboratory in the School of Food Science at WSU-Pullman.

“Potassium chloride, especially, tastes really bitter and people really don’t like it,” Ross said.

The researchers used tasting panels and WSU’s electronic tongue to see just how much they could add of the replacement salts for standard sodium chloride before people found the food unacceptable to eat.

Some tasting panels tested a variety of salt solutions, or salt in water, while others tested different salt combinations in tomato soup.

Using the e-tongue and panels, they found that a blend using approximately 96.4 percent sodium chloride with 1.6 percent potassium chloride and 2 percent calcium chloride was the ideal reduction.

They had a higher reduction when they added only calcium chloride, getting acceptable rates with a combination of 78 percent sodium chloride and 22 percent calcium chloride.

“This combination of the two salts did not significantly differ compared to 100 percent sodium chloride,” Ross said. “But when we added potassium chloride, consumer acceptance decreased.”

3 trays full of white plastic cups, the cups on each tray have a different 3 digit number.
Different combinations of salt are stacked up for human tasters to try in a trial.

Recent findings have suggested that gradual reductions in salt over a period of years is the best way to reduce salt consumption. Using one of these blends for a specified time frame could lead to greater reductions down the road.

“It’s a stealth approach, not like buying the ‘reduced salt’ option, which people generally don’t like,” Ross said. “If we can stair-step people down, then we increase health while still making food that people want to eat.”