[Soup] In addition to the five flavors, there is also a sixth and seventh flavor?

Are you having a great Lunar New Year holiday?

Some of you may have had a good time with your family that you have been wanting to go back to your hometown for a long time.

When it comes to holidays, the first thing that comes to mind is delicious food.

What flavor and food do you like the most?

Five tastes... Astringency is not taste?

The human tongue senses five tastes called five tastes.

Sweet, salty, sour, bitter, what other flavors are there?

Spicy, astringent, and greasy come to mind.

However, spicy taste is classified as pain sensation and astringent taste as pressure sensation.

So what is the one thing left?

It's just savory.

Taste is a vital sense that provides the ability to evaluate what to eat and drink.

It's to consume nutrients and avoid toxins, but we've also evolved to choose foods we like or dislike.

Sweetness allows us to properly consume the carbohydrates our body needs to make energy.

Sour taste allows us to recognize unripe fruit and spoiled food.

The salty taste allows you to regulate the proper amount of water in your body by consuming adequate salt.

The bitter taste prevents toxic substances from entering the body.

Umami helps you get the right amount of protein for growth and maintenance.

What kind of taste is umami?

Among the five flavor words written in the picture, do you see the word umami (うま味) on the far right?

It is a combination of the words 'umai' meaning delicious and 'taste'.

If 'Oishii', which we commonly know as delicious, is a more polite expression, 'Umai' is a more one-dimensional expression.

Umami is translated as umami in Korean.

If you look up the Korean dictionary, it says that umami is 1. the taste that food pulls in your mouth, and 2. the power to pull your heart.

In English, it is translated as savory, but it has the meaning of 1. delicious, fragrant, savory, 2. pleasant, pleasant.

The history of umami is not as old as you might think.

In 1907, Professor Kikunae Ikeda of the University of Tokyo in Japan tasted the soup while eating dinner and it was so delicious that he asked his wife what it was made of, and the answer was kelp soup.

He called the taste 'umami' and after analyzing the composition of the broth, he finally discovered in 1908 that the source of the taste was glutamic acid, a type of amino acid.

(Foods such as cheese, pickled meat, tomatoes, mushrooms, salmon, steak, anchovies, and breast milk also contain glutamic acid.) One year later, a seasoning called monosodium glutamate (MSG) was developed by combining glutamic acid and sodium. was discovered, and it was named “Ajinomoto” (味の素) and made into a product.

By the way, the substance of the taste was there, but we couldn't figure out how we felt it.

It wasn't until 2002, more than 90 years after the discovery of umami, that a US-based research team discovered a receptor that senses umami on the tongue.

This discovery proves that umami is really just another taste on the tongue.

receptors for taste

The papilla, which are small projections on the surface of the tongue, contain taste receptor cells that detect taste.

50 to 150 of these cells gather in the shape of a rosette to form a taste bud.

Taste receptor cells are not nerve cells, but they are very much like nerve cells.

What you see on the right side of the blue bud shape is the microvilli, where taste receptors are distributed and meet substances that stimulate the sense of taste.

Within a single taste bud, some receptor cells detect sweetness, while other cells have receptors for bitter, sour, salty, and umami, and receive each taste.

The average lifespan of these cells is very short, about 10 days.

Surprisingly, it wasn't that long ago that receptors for bitter taste (2000), sweet taste (2001), sour taste (2006), and salt taste (2010), which have a longer history than umami taste, were discovered.

All of them were discovered through the research team of Professor Charles S. Zuker, who discovered umami receptors.

In 1999, the research team discovered two receptors expressed in taste bud cells on the tongue and named them T1R1 and T1R2, respectively.

At this time, we assumed that these were taste receptors, but we did not know which flavors they detect.

Another research team announced the results of a study that found that people who do not feel the bitter taste of PROP (6-n-propyl-2-thiouracil) have a mutation at a specific location on chromosome 5. The gene for T1R2 was located elsewhere.

So the research team thought that there must be a separate receptor that detects bitter taste, and eventually discovered a group of receptors called T2R.

They also revealed that they can detect bitter tastes.

There are thousands of molecules that produce bitter taste, but there are about 30 types of T2R, which are bitter taste receptors.

Here, various bitter molecules combine to detect bitterness.

The molecules responsible for taste are very diverse, but the number of taste receptors is comparatively small.

Each taste receptor cell appears to have receptors for one type of taste.

In 2001, sweet receptors were identified following bitter taste, and in 2002, the umami receptors mentioned above were identified.

When T1R2 and T1R3 are combined, sweet taste is detected, and when T1R1 and T1R3 are combined, umami taste is sensed.

Both sweetness and umami taste good.

What both receptors have in common is that they have T1R3.

However, T1R1 and T1R2 were not expressed simultaneously in one cell because sweetness and umami taste must be delivered to the brain through different pathways.

Taste, tongue to brain

Over time, in 2015, Professor Zucker's research team confirmed that the central nervous system also has neurons that respond to individual tastes.

When the gustatory neurons in the central nervous system of the rats were activated, they were labeled with fluorescence, and after giving them five flavors of food, they observed them through an endoscope. Different central nerve cells responded to each taste.

This result shows that the tongue that senses taste and the central nervous system that senses it are tightly connected.

Taste Map of the Tongue

Do you remember a picture similar to this one?

It is a so-called 'taste map' that showed which parts of the tongue tasted in school days.

I remember seeing the picture and rolling the candy all over the place in my mouth to see if I could feel the sweetness really well on the tip of my tongue.

**If the 'Go to View' button is not pressed, you can view the address by moving it to the address bar.