Salt is the Charm

We do love sweet, salty, sour, bitter, and umami (the taste of glutamic acid), which has strengthened its place in the gastronomy world in recent years. Besides culinary enthusiasts and chefs, these tastes also attract the attention of scientists. A new study published in Science investigated the biological process of why adding some salt to desserts enhances the flavour.

We are able to taste our food with the help of taste buds on our tongues (the sense of smell plays an important role too, of course). T1R is the name of the receptor family that allows us to detect sugary, sweet foods. These receptors can detect both natural and artificial sweeteners (such as saccharine). In theory, sugary stimulants were thought to lose effect if the T1R was inactivated. However, a study in 2003 had shown that mice with knocked-out T1R genes still loved glucose. Thus, the existence of another mechanism detecting sugary foods in mice, and possibly humans, aroused interest.

Later, scientists started studying a protein called SGLT1 that transports glucose inside the body. SGLT1 (sodium-glucose cotransporter 1) carries glucose with the help of sodium to provide energy for cells in the kidneys and intestines. The same transporter protein is also found in cells that help us detect sugar in food.

When scientists gave unconscious T1R mice a mixture of sodium (i.e. salt) and glucose, they noticed that the nerves connected to their taste cells were rapidly fired. However, when the same mice were given only glucose, the response was not that rapid.

It is also stated that glucose cannot be detected when a compound known to suppress the SGLT1 protein comes into play. So, SGLT1 really does seem to be the underlying factor in this mechanism.

The experts who conducted the study add that we have three different taste cells allowing us to detect sweet flavours. The first two use either the T1R or SGLT1 pathway, together with allowing us to distinguish between natural sweeteners and artificial sweeteners. The third, according to the researchers, uses both pathways at the same time, also responding to fatty acids and umami flavours -so that we can detect foods rich in calories.

Considering that even mice with T1R inactivated receptors are able to detect glucose when sugar is taken with salt, we may say that adding a little salt to sugary foods will definitely enhance the flavour for normal mice, and also for humans.

Gastronomes already know that adding a pinch of salt to food reduces bitterness, strengthening the sweet, sour, and umami flavours. In higher amounts, it suppresses sugar and strengthens umami. Since salt (sodium chloride, ie NaCl) can be obtained in pure form, it is one of the most indispensable elements of every kitchen around the world. The next time you say “pass the salt” during a meal, remember that it is one of the most essential minerals for the survival of humans (and other animals).