Umami

How many basic tastes do we have? Sweet, salty, sour and bitter, one will answer quickly.
No so fast. There is one more, umami.
There was quite a debate starting with year 1908 when the Japanese Kikunae Ikeda  proposed it. The name umami comes from Japanese and means pleasant savory taste.
Only in 1985 the scientific world accepted this taste as the taste of glutamate and nucleotides.

 To identify umami think of a bowl of hot pasta with a delicious tomato sauce and parmesan cheese, a freshly grilled steak or fish, a mushroom dish, a stir-fried seafood or a dish of chicken with sofrito sauce. These flavors result from centuries of culinary tradition, including careful attention to ingredients and preparation.
The quality of the ingredients is essential and don't expect a dish made with frozen vegetables or vegetables
grown in a greenhouse to have the same umami as a dish made with fresh vegetables straight from the garden.

But still if cooked properly, your dish will have umami, a savory taste.

Umami depends on the concentration of glutamates and nucleotides and on salt. Eat food together with lots of bread or add too much salt, and, voila, less umami. I think sugar also diminishes umami. Green tea is more pleasant to the tongue if you don't add sugar.
Umami is good news for people who have to reduce as much as possible salt.
Soup with a proper concentration of the ingredients and less salt is delicious. Otherwise is like salted water.
Umami isn't lost in old age like other basic tastes or smell. This means old people can enjoy better the food if properly cooked, have a proper nutrition and be healthier.
Umami is present naturally in meat and vegetables. It can be found mostly in fish, seafood, cured meat, mushrooms, tomatoes, celery, green tea, cheese (especially parmesan), soy sauce
Babies meet with this taste from the very beginning in mother's milk. Breast milk has the same concentration of umami goodies as a good concentrated soup of fish or bones, meat and vegetables.

Glutamate, one of the umami ingredients, is an amino acid, found in all protein-containing foods.
Monosodium glutamate, or MSG, is the sodium salt of glutamate. When MSG is added to foods, it provides a similar flavoring function as the glutamate that occurs naturally in food. MSG is comprised of nothing more than water, sodium and glutamate.
In the early 1900s, MSG was extracted from natural protein-rich foods such as seaweed. Today, MSG is made from starch, corn sugar or molasses from sugar cane or sugar beets. MSG is produced by a natural fermentation process that has been used for centuries to make such common foods as beer, vinegar and yogurt.
Scientific knowledge says MSG might be ok for your health. However, any Chinese will tell you not to use it for baked recipes as it will give you the headache of your life.
And some people complain anyway of headaches after eating food with MSG.
There is also this rumor, that MSG triggers obesity. Nothing is proved on this to date but...Researches have changed their minds so often that I wouldn't be surprised if one day they'll decide we have too much MSG in  foods. Food industry is using MSG on a large scale to improve food taste and I guess some people already have quite a lot of MSG in their daily menu.
A bit of MSG now and then won't hurt. However I'll try to avoid it as much as possible.
When in doubt, better don't eat it.
For the moment, I'll stick to good old traditional umami.


References
Everything You Need To Know About Glutamate And Monosodium Glutamate
Wikipedia - Umami