“Science of Salt”

It’s a kitchen essential. It’s a basic ingredient in recipes. It is found on every dining table. It is cheap yet its culinary value is priceless. What is it? You’ve probably guessed it by now.

Salt. It is the only rock that we eat and is so ingrained in our everyday lives that we don’t really give its background much thought. It is a nutrient that our bodies need in order to survive. It plays a vital role in the body’s water balance, muscle contraction, and nerve conduction. Hence, it is not surprising that our body has a natural inclination towards salt. Not only does it balance general flavor and have a special alluring taste, it also aids in forming the preferred texture, and helps in food preservation for some particular foods.

From an evolutionary perspective, the ability to detect salt arose as a reaction to the sodium needs of organisms that exclusively ate plants. Since sodium is vital for physiological processes, researchers claim there are two conditions under which salt is consumed by animals. The first, aptly named “salt need”, is when there is a true need for sodium by the body and there is an innate response to consume it. The second is known as “salt preference” which is when there is adequate sodium in the body, but we continue to consume it. This is evident by global popularity of salty foods in current fast food culture.

Since the Maldives is surrounded by the great big Indian Ocean, practically a reservoir of salt, the obvious assumption is that we collected sea salt by boiling sea water. As it turns out, Maldivians used salt water to cook and give our favorite tuna dishes its salty flavor instead of adding salt by itself. Francois Pyrard mentions this in his book “The voyage of François Pyrard of Laval to the East Indies, the Maldives, the Moluccas and Brazil” followed by the fact that many Maldivians were plighted with ringworm and other such diseases due to a large amount of salt fish we consumed.

Moving on to the mechanism behind the detection of saltiness in our body, salty taste depends on the dissociation of the Sodium Chloride ions (individually charged atoms). Though researchers have currently identified the Sodium ion to be responsible for saltiness, it seems that the chloride ion plays a role as well. When the size of the chloride ion increases, the level of saltiness decreases. The complete understanding behind reception of salt taste still remains a mystery but researchers have successfully identified that two or more receptors that are responsible for eliciting salt tastes.

The most well-known hypothesis regarding this states one set of receptors playing a role in salt taste perception involves ion channels or “pores”. This channel is known as the Epithelial Sodium channel (ENaC). It allows sodium dissolved in saliva to migrate from inside the taste receptor cell from the outside. The ensuing spike in Sodium ions into the taste cell causes the discharge of neurotransmitters that ultimately signal the taste of salt to the brain. The existence of receptors other than ENaC is thought to exist due to evidence of some salt taste being perceived even when cations that cannot fit into the ENaC (potassium, calcium, ammonium) are present, instead of sodium or lithium.

Research has also found that salt improves the perception of thickness, heightens sweetness, disguises metallic or chemical off-notes, and round outs overall flavor while enhancing flavor intensity. This was tested by gradually increasing salt content to soup and inspecting for increased thickness, fullness and balance. The mechanism behind this is not fully understood. Researchers are stumped as to how salt enhances the perceived thickness of liquids such as soups.

Though not yet proven, it is hypothesized that salt may also interact with somatosensory (touch) neural systems as well as salt taste receptors. On the other hand, researchers have understood the mechanism behind the ability of salt containing compounds to improve flavor by suppressing bitterness. In turn, flavors such as sweetness, sourness, and umami (savory) become heightened. The study added a sodium compound to sugar solutions with urea and without it. The result found no change in sweetness in the sugar solution without urea in it, yet perceived sweetness for the sugar solution with urea in it had increased. Leading to the conclusion that the improved sweet taste is a consequence of salt suppressing the bitter taste.

Professional chefs all generally agree that seasoning is quintessential for good flavor. Therefore, we cannot ignore the importance of salt. Salt is not the villain current health fads have made it out to be. Despite the health concerns from its overuse, the correct moderation of salt will not only fulfill your biological need for sodium while allowing you to fully enjoy the flavors of your food.

Words by Afaaf Adam