Sodium is an essential component of body chemistry. But lately salt has joined the rogues gallery of suspect food ingredients as more becomes known about the role of high sodium levels in promoting hypertension in some people.
"High blood pressure is one of the three most important risk factors for health and for long life; it is as or more important than smoking and height-to-weight ratio," according to Dr. Wayne Heidenreich, a Milwaukee consultant in the insurance industry.
But the relationship of sodium intake to high blood pressure has not been conclusively established, said Kantha Shelke, a Chicago food chemist who is a Functional Ingredients contributor. As little as 2 percent of the population may have the genetic abnormalities that directly link high sodium levels with hypertension.
The data notwithstanding, sodium seems to be becoming the new bogeyman. "What consumers believe does not need any rhyme or reason," Shelke said.
According to Mintel, a leading market research firm, 51 percent of U.S. consumers say they are always or usually watching their sodium intake. Sodium reduction will be one of the leading trends for consumer packaged goods manufacturers in 2010, the analysts say. Mintel predicts that more CPG marketers will follow in the steps of ConAgra foods, which has pledged to reduce the salt in its products by 20 percent by 2015.
Among the three big risk factors, most people find sodium intake as it relates to hypertension is probably the easiest to control, Heidenreich said. One thing people can do immediately is make different choices at the supermarket, he said.
"Without question, the one largest thread of salt in the diet is from prepared foods," he said.
So it's time to start getting the salt out. The question is, how?
"The primary reason salt is added to any food is to bring out the flavour," Shelke said. "It is used in practically everything."
But salt has other functions too, Shelke said. It acts as a preservative in canned foods and stiffens the gluten structure of baked goods, among other properties. So a manufacturer seeking to reduce or replace salt may have to choose one ingredient for flavour and another to replace a functional property of salt. And these choices are likely to be specific to each product, Shelke said, increasing complexity and cost.
Ingredient suppliers are taking a number of approaches to salt reduction, such as modifying crystal structures to make salt taste saltier, formulating additives to enhance the salty taste or to perform some of salt's flavour masking functions, or finding substitutes that do away with sodium altogether.
From a food formulations perspective, easier said than done. "There is no silver bullet to removing sodium from food products," says Carlos Rodriguez, marketing manager for Cargill's salt business unit, and substitution is not a one-for-one process. Cargill offers three ingredients, each with a unique purpose — Premier™ potassium chloride (potassium and sodium balance), SaltWise® sodium reduction system (25 to 50 percent sodium reduction) and Alberger® Brand Salt (hollow pyramid shape for topical salt applications).
Five noteworthy developments in the salt-substitution front in recent years include:
- Nu-Tek Products' LS 17000 Low Sodium Sea Salt, an ingredient in Campbell's line of Select Harvest low-sodium soups. The ingredient offers a 50 percent reduction of salt in typical formulations, the company says.
- Senomyx, a California flavour-ingredients company, announced in 2008 that it had isolated the primary human salt taste receptor, a protein called SNMX-29. Using the protein in tests, the company says it has identified 250 compounds that help foods taste saltier, two of which they have patented.
- Givaudan, the Swiss-based fragrance and flavour leader, is focusing on fermentation products that enhance salty flavors. Both Senomyx's and Givaudan's additives allow salt to be reduced while keeping the same level of salty flavor.
- AlsoSalt, a Seattle-area company that manufactures an eponymous salt substitute, seeks to replace rather than reduce sodium. "Everybody and their brother say they have salt substitutes and pretty much they're all using salt," said CEO Joan Watsabaugh. AlsoSalt's patented process uses the amino acid lysine to mask the bitter flavour of potassium chloride. AlsoSalt is the key ingredient of Heinz No Salt Ketchup.
- Redpoint Bio, a New Jersey-based taste-additive company, also bases its BetraSalt product on potassium chloride. The product uses what the company calls "a combination of GRAS ingredients" to mask the bitterness.