Prof. Lisa Duizer in Guelph's Food Sensory lab -- Photo by Martin Schwalbe

Through processed foods at restaurants and supermarkets, Canadians are eating more than twice their recommended daily salt allowance. This constant sodium overload brings the increased risk of hypertension, serious heart disease and stroke. Guelph researchers say, however, that people won’t give up their favourite salty foods overnight.

Reduced-salt foods need to be able to satisfy people’s craving for the same salty taste. And that’s where food science professor Lisa Duizer, along with master’s student Matt Rietberg and undergraduate Derek Vella, is laying the groundwork. They are part of a multidisciplinary, multi-institutional research team led by Ryerson University food scientist Dérick Rousseau that is developing new approaches to reducing salt consumption.

One idea is to use emulsions for a more gradual, controlled salt release. In this way, consumers will taste saltiness over a longer period and beat the urge to reach for the salt shaker for an extra shake. But will this approach satisfy the public’s salty cravings? That’s what Duizer’s sensory lab will find out by studying different salt tastes and concentrations.

“Everyone has a different relationship to salty tastes,” says Duizer. “Some people can find a lot of saltiness appealing, while others could find it repulsive.”

She says one type of emulsion doesn’t fit all foods; an acceptable level of saltiness for one product may not be acceptable for another. That’s why the researchers are trying to determine the role salt plays and how it behaves as a structural component in a variety of different foods, such as soups, breads and cheeses. The Rousseau team will try to re-engineer and tailor emulsions as needed, depending on how they are used.

Another major part of the work involves studying how salt interacts with and is broken down by saliva and how it is detected by human taste buds. Duizer’s lab is using a specially trained salt-tasting panel to determine the right combination between taste and viscosity so that the emulsions can deliver the most appealing and functional taste and texture.

Reducing salt doesn’t just impact taste. Sodium plays an important role in many foods as a preservative or as a structural component that helps to form an appealing texture. Duizer’s future work will determine how the taste, texture and structure of both liquid and solid foods are affected by an altered salt content.

“It’s not strictly a taste issue,” she says. “Salt is also a safety component, so we need to find that fine balance with the emulsions between function and acceptable tastes.”

This research is funded by the Advanced Food and Materials Network of Canada.