Demand for low-sodium foods is as strong as the growth in the gourmet salt market. What’s behind the dichotomy? Consumers realize salt is not quite the danger they’ve been led to believe. Nevertheless, they still feel compelled to proceed with caution through a barrage of sound-bite science.
Compounding the problem, both sides of the “to salt, or not to salt” contest are getting louder in pitches to influence consumers. Meanwhile, processors want to find a comfort zone delineating salt and sodium’s true place in new product development.
This conundrum of gourmet salt vs. low-salt could pose a challenge for processors. However, it also allows them to take advantage of some unique marketing opportunities. Suppliers’ ingredient technologists have created several interesting new blends of mineral salts. Elsewhere, supplier and processor research chefs are learning to create increasingly exotic flavored salt blends and infused sea salts.
By the Numbers
This is not some cynical bid to sell both rocks and window panes during a riot—but a recognition by ingredient experts about the true nature of salt and health science. For example, the 2010 Bernstein-Willett Harvard School of Public Health study showed sodium consumption in the American diet to be unchanged after more than half a century. Yet, incidence of hypertension—in defiance of the laws of presumed cause and effect—rose dramatically during the same time.
Putting the salt and health question in general perspective, since the earliest salt/sodium-hypertension/cardiovascular disease research of the 1940s, the majority of the hundreds of properly conducted and controlled studies have failed to establish a definitive connection between dietary sodium intake and direct-cause disease states in healthy persons. In fact, some of the more modern studies are demonstrating tangible dangers and risks with low-sodium diets in certain populations. (Keep in mind, for every properly conducted and controlled study, there are at the very least an equal number of poorly conducted and uncontrolled studies.)
But the key in all this involves that qualified demographic: “healthy persons.” And, unfortunately, there are tens of millions of Americans who are not healthy, especially as due to obesity and the chronic inflammation, metabolic damage, hormonal imbalance and secondary diseases brought on by obesity. These include compromises of kidney function. The kidneys are the primary regulators of sodium, potassium and other metabolic electrolytes.
The determined campaign against salt could be viewed as the most pervasive example in nutrition of a mistaken belief being repeated often enough until it has become impervious to all evidence to the contrary. Numbers-wise, only one in 10 persons or so—the approximate percent of the population with a tendency toward or medically established sodium-sensitive hypertension—should keep an eye on his or her salt intake. And some experts put the figure at as low as 2-4%.
Still, this is where diabetes, hypertension and compromised kidney and cardiovascular function enter the picture. While—even among this demographic—salt sensitivity is less common than consumers are led to believe, the numbers are sufficient to warrant availability of excellent reduced- and low-sodium products. The market continues to prove this, too.
So, the challenge becomes, how do processors serve all salt masters?
Salt’s Chemistry of Taste
Sodium is classified as an alkali metal, appearing in the first family of elements of the periodic table. Other family members include lithium, potassium, rubidium and cesium. The three dimensional structure of the taste bud receptors is responsible for the specificity of taste sensations. In the case of salt the sodium ion produces the most intense salty sensation because its size is well suited to the salty receptors on the tongue.
Other types of salts with either monovalent or divalent cations (examples: ammonium, calcium) interact with the taste receptors to produce bitter flavors, not salty taste. Different alkali metal family members also can produce varying degrees of salty perception, but they tend to be not as intense as sodium.
When chemists compare the flavor impact of these other compounds, sodium chloride is given a saltiness index rating of 1.0. Potassium chloride, a workhorse ingredient in salt and sodium replacement formulations, has a saltiness index of 0.6.
Lithium and potassium ions are the most similar in size, the former being smaller and the latter being larger that the sodium ion. Both create a salty impression in the mouth, but neither is as effective or as desireable as sodium. And other metallic salts have side effects that run from benign to undesired to possibly dangerous.
Sodium chloride is an ionic solid that is readily soluble in water, and therefore is highly soluble in saliva. The taste of salt is attributed primarily to sodium ions liberated from the sodium chloride crystal as it dissolves in saliva. The intensity of the salty taste is directly related to the number of sodium ions that interact with the salty receptors in the mouth.
The rate of saltiness detection is related to the rate of dissolution of salt crystals in the saliva, and therefore is a direct result of the overall surface area of the salt particles. Higher surface area results in more rapid release of sodium ions which results in a more intense salty taste. This is where the shape, size and textures of salt crystals can have significant effects on perception of saltiness.
Long Lost Shaker
Generally, salt is thought of in terms of the salt shaker sitting on the table; that is, salt is rarely considered beyond its most overt role as a flavoring agent for many of our favorite foods. While this is mostly the case, it also is important to realize that salt fulfills a number of other functions in food products and their manufacture. Of course, salt has a centuries-long history of use as a food preservative. But it also modifies the ionic strength of liquids in which it is dissolved. Plus it acts as a flavor potentiator, enhancing or modifying other flavors.
Even chocolate milk is commonly formulated with a low level of salt. The salt content is not high enough to produce a salty impression, but it does greatly enhance the flavor impact of the chocolate. In fact, salt interacts quite well on the palate with chocolate and intense, caramelized sugar sweets. It’s no coincidence there’s been a veritable explosion of salted chocolate and salted caramel confections.
Flavor is made up of more than just signals elicited from taste receptors in the mouth. Aroma is an important component of flavor, as is texture or mouthfeel. The thermal temperature of food also contributes to flavor, as does the non-thermal cool or heat perceptions that arise from flavor chemicals such as menthol or capsaicin (the pungent component in chili peppers).
Saltiness is one of the five primary flavor categories, and is the only one directly attributed to a substance that is critical to life: salt, or more properly sodium chloride. Sodium and chloride are vital components in nerve signaling and conduction processes in the body, and this includes cardiac rhythm.
Aside from flavor-defect challenges that arise from the use of some sodium replacement ingredients, there are other issues that can arise. Determining all such challenges can be complicated for the ingredient technologist as well as the food formulator because so many of these issues are application dependent, but the following example helps illustrate the difficulty.
One important source of salt in the American diet is bread and related risen bakery products. Not only does salt enhance the flavor of the bread, it moderates the activity of the yeast and enhances the ability of the gluten in the flour to absorb water. If one attempts to simply remove the salt from a typical bread dough formulation, certain immediate effects are observed.
Aside from flavor, the salt in the dough modifies the ionic strength of the water in the system. This affects the ability of gluten to take up and hold water resulting in wetter and looser dough. In addition, removal of the salt leads to increased yeast activity, which increases the dough proofing rate. The interactions of all these elements and forces will determine whether or not the baker will get bread in return for the efforts and resources applied.
Technologists creating salt reduction ingredients for baked applications commonly package them as systems with other ingredients to balance all three aspects served by sodium chloride. There will be adjustments to leavening, and at least some salt as sodium chloride often will have to be used to support the salt reduction component.
How to Lower Salt
There are two standard approaches to the hands-on mechanics of achieving sodium reduction in the diet: removing it and replacing it.
Removing salt from a formulation has two drawbacks. The first is that salt is one of the key food safety ingredients in food production and preservation and, in some products, extremely difficult to remove without compromising food safety. Meats and baked products are among those that benefit the most from the salt in their recipes.
The second is a fundamental issue that has been well established in mammalian eating habits (yet continues to be largely ignored): If you remove salt at one end, it gets added back in at the other. As was proven by the aforementioned Bernstein-Willett study, more than 50 years of persistent petitioning the public to avoid sodium and the concomitant aggressive reduction of salt in prepared foods had virtually zero impact on overall salt consumption. There’s a well-known “set point” for dietary salt not just among humans but among all warm-blooded animals.
The most common of the two strategies for salt reduction is the sodium replacement strategy. Of these replacers, potassium chloride is the most common. However, for reasons explained in more detail below, potassium tends to be substituted for only a portion of the sodium chloride in a sodium reduction formulation. The intent is to reduce the sodium content and maintain the salty taste. Meanwhile, there are well-known drawbacks to potassium chloride, one of which is the fact that its overuse imparts a metallic taste to food.
In the effort to address the flavor defects associated with traditional salt replacement methods, flavor companies have formulated flavor masking preparations that offset or mask the off flavors associated with potassium chloride. However, these flavor systems can present drawbacks. Although they mitigate the off flavors, they also tend to be substantially more expensive than salt itself when considered on a cost-in-use basis.
While the use of potassium chloride might be the most popular salt reduction technique, it has come under fire from some health advisors—but from two different sides. The World Health Organization estimates that consumers are in the midst of a potassium deficit crisis (something of an irony, because foods with sodium typically contain balancing potassium; so reducing one reduces the other).
The population that actually needs to reduce sodium in the diet—those who are not healthy and whose health conditions compromise function of the kidneys—could find too much potassium in their diet can be just as harmful or even more dangerous than the sodium it is replacing.
This is another key reason why salt reduction formulators have combined potassium chloride with either sodium chloride or other ingredients.
For baking applications, a common solution is to use leavening acids that compensate. These include phosphates of sodium, aluminum and calcium, as well as similar weak acids, such as calcium carbonate, monopotassium tartarate, sodium bicarbonate and others. And, recently, makers of such systems have looked more closely at the role the structure of a salt crystal plays in saltiness perception to create comprehensively functioning salt reduction systems that also are safe for the vast majority of the population.
Shape of Things to Come
Given that texture influences taste—and that the surface area of a salt particle influences the perception of salty taste—researchers are emphasizing the actual morphology (shape, size, surface texture) of salt particles. These all can have a fundamental impact on the perception of saltiness. Some salt reduction strategies have involved manipulation of salt particle morphology.
One approach is to replace granulated salt with finely ground salt. By greatly reducing the particle size, the salt effect can be enhanced while the total amount of sodium chloride is reduced, and the finished product achieves the same salty taste perception. Taking such solutions to the extreme is a technology that creates hollow salt microspheres only a tenth or so the size of a standard salt crystal. They give the effect of larger particles on the surface, while dramatically lowering the actual amount of salt present in the particle.
Other shapes and sizes have an impact on surface area—and therefore saltiness flavor—as well. Chefs have known for decades that flaked salts can impart bolder flavor.
“As far as what works best with what application, it comes down more to the texture of the salt itself instead of the flavor,” says Megan O’Keefe, “Serious Salter” (her title) for SaltWorks Inc., makers and retailers of a comprehensive line of dozens of global, flavored, infused and smoked salts. “Flaky salts work best for a topping or adding texture, with small flakes also working well in a solution as they dissolve quickly, dispersing an even flavor.”
O’Keefe notes also that “more dense, large crystals work well for inclusions, as they hold their texture and crunch best in this sort of application.” She further recommends fine sea salts for when only the flavor—without texture alteration—is desired. This is especially suited to salt as an ingredient versus a topping or inclusion.
For years, so-called “kosher salt” has been a staple in this arena. The flat flakes are actually not so named because they themselves are kosher, but because they are used in the koshering process of meat, wherein as much blood must be removed as possible. Their unique shape causes them to absorb blood quickly and efficiently. This, too, allows them to enhance flavor in a formulation by holding on to savory flavor components that might otherwise be lost or dissipated in preparation and cooking.
One of the more flavorful and visually exciting salt crystal shapes are hollow pyramids. These combine the most surface area with a flakiness and light crunch that is especially good at enhancing sweet flavors. The flakes melt quickly on the tongue and hold flavors without being harsh.
Just a Dash
Other technologists have responded to the salt/sodium reduction challenge by developing flavoring systems that enhance food and beverage flavor without the use of added salt or salt replacers. These can be blends of flavorants, yeasts, herbs and spices that are applied to food to enhance the characteristic flavors.
A drawback of this approach is that these systems, too, are typically much more expensive than salt, plus they must frequently be customized to individual applications. For example, powdered lemon peel and rosemary extract might make excellent and flavorful salt enhancers in a soup or stew formulation, they’d hardly do for the previously noted chocolate milk beverage.
That’s where the biggest trend in sodium chloride—gourmet sea salt—comes in. Only a few years ago, pink, red and black salts were on the fringe. As the uniqueness in flavor and performance of these ingredients excited consumers, saltmasters pursued smoked salts and the current break-outs, herb-, spice-, vegetable- and fruit-infused salts.
How the different varieties will perform in specific recipes can be dependent on the recipe itself as well as the shelf stability of the final product formulation, notes SaltWorks’ O’Keefe.
“Typically, the advantage of using a flavored or infused salt is two-fold,” she says. “First, it simplifies the process to use just one ingredient versus several, and is especially valuable when used in topping or inclusion applications. Secondly, a flavored or infused salt offers a balanced flavor ratio with the salt. This is also best highlighted when it’s used as a topping or inclusion.”
“In general the salts and their flavors will hold up and act in the same manner that you would expect of their individual components,” says O’Keefe. “The smoked salt’s flavor holds up very well and, while some have stronger smokiness than others, there’s not a concern that the smokiness will become stronger over time in the formulation or concern about the salt changing the recipe and taking over the flavor profile.”
“Smoked salts vary widely in level of smokiness,” concurs Didi Davis, owner of Salt Traders LLC. “Some are mild and subtle; others big and bonfire-esque and able to knock one over with their flavor.”
These salts are best used for such recipes as rubs or to apply smokiness in place of artificial smoke in meat and stew formulations.
“Once seasoned to the correct level of flavor, and depending on the processor, the flavors will stay fixed within the shelf life of the item they go into,” O’Keefe says. “Usually flavored salts are used as an added enhancement or accent applied to the surface of a dish—not as a full replacement for all the salt within a recipe. Smoked salts have been used in everything from soups and sauces to frozen snacks to confection toppings with great results.”
It’s a new season for food formulators. It appears that the overriding fear of salt is fading. Meanwhile, more consumers are enjoying the excitement of the discovery of flavored and infused salts in all their variety and versatility. Put together, these stronger, shapely salts and smarter sodium technologies provide the best sodium balance.
Too Little Too Late
The controversy regarding dietary sodium has been typified by far more hysteria than fact. While it is cautious to point to the lack of scientific backing for reduction of sodium in the diets of healthy persons, increasingly the evidence supports the idea that too little salt also is dangerous. And, indications are that this extends even to non-healthy persons.
For example, a 2008 Italian study of 232 randomly assigned patients with aggressively treated moderate to severe congestive heart failure consumed either 2,760mg or 1,840mg sodium/day, all on the same controlled diet. The lower level sodium group experienced more than three times the number of hospital re-admissions as the higher-sodium group (30 vs. nine), and two and a half times as many deaths (15 vs. six).
A 2011 study followed 28,800 persons with high blood pressure aged 55 and older for nearly five years. Researchers analyzed sodium consumption by urinalysis. Results showed that the risks of heart attacks, strokes, congestive heart failure and death from heart disease increased significantly for those consuming more than 7,000mg of sodium a day and for those consuming fewer than 3,000mg of sodium a day. Worldwide, consumers’ average sodium intake tends to fall within the band, in between the extremes. This supports the theory of a natural sodium set-point.
By Didi Davis
The best way to choose from the scores of smoked salts and herb-, spice-, vegetable- and fruit-infused salts is to conduct one’s own taste test. In addition to trying out different salts with the intended formulation, try them with a polar opposite as well. For example, use a volcanic flaked salt with both a dark chocolate caramel and in a vegetable soup. Or try a light pyramid salt gently sprinkled over fresh cut fruit and on top of a melted cheese canapé. For processors, even some of the once-exotic gourmet sea salts are becoming more mainstream and thus cost-effective when used as a marketable point of difference.
Here are brief reviews of some of the more common (read: less expensive) gourmet salts worth investigating.
Cornish Sea Salt: This salt has a clean, pure taste with a touch of sweetness. No “sea water” flavor or bitterness. The medium-size crystals have a firm crunch and melt slowly.
Hawaiian Red Alaea Sea Salt: These salt crystals are small to medium is size, yet still with a good crunch. The traditional red color comes from the addition of Hawaiian red kaolin clay, giving the salt an earthy, soft flavor.
Himalayan Pink Sea Salt: The fine grain crystals melt quickly and add a mild, somewhat sweet, flavor. 84 trace minerals round out the gentle quality of the salt. An excellent choice for all applications.
Grey Sea Salt: Another good choice for all applications. Crystals may be fine or coarse. The flavor is quite different from Himalayan Pink as it lacks any subtle sweetness. Salt is moist with a big mineral flavor because it is harvested from the bottom of the salt pans. The flavor blossoms and lingers in the mouth.
White Cyprus Sea Salt Flakes: These pyramid-shaped flakes are mica thin, light and crisp on the tongue, dissolving quickly. The salt has a rich, balanced flavor, not harshly salty.
Apple Wood Smoked Sea Salt: This salt first tastes sweet, like maple bacon. As crystals linger in the mouth, the elements of salty-sweet-smoky grow to a full, complete balance of flavor. The smoke is authentic, not added, without a harsh or bitter aftertaste.
Didi Davis is a chef, food writer, teacher and owner of Salt Traders (www.salttraders.com), specializing in sea salt, pepper, sugar and spice blends. She is the author of two cookbooks.