Basically the “hearty” feeling is generated by MSG(Monosodium Glutamate) in some form.

One thing that quite a lot of people are not aware of is MSG exist in natural food. Meat product, Chesse, potato, tomato, mushrooms, eggs are natural MSG sources. And these natural food do possess a high amount of natural MSG – that is why they all taste so good most of the time. In Japanese cuisine, miso paste are widely used (and in other variation, konbucha is also used). Most of the miso paste is added with MSG, and usually the MSG is extracted from seaweed. This is also one of the open secret why Chinese food taste so good. It is because of the MSG.

MSG can either be extracted from meat or vegetables. In meat, pig protein is used as a cheap means of extracting MSG. While to make the MSG kosher, it can also be extracted from plants like seaweed.

My view on MSG is that it doesn’t really harm you. Added MSG and natural MSG are the same. It is not neccessarily unhealthy to have MSG as long as you are not eating excess amount of it. And having some MSG in food (natural or not) will sometimes reduce the urge for salt. The good side is you will consume relatively less salt and might yield a better option if your diet has a constraint in daily salt intake. There are certainly people who are intolerant to MSG, but the occurance of such events are actually not especially high, and unfortunately most of the processed food will use MSG as a form of addictive to make their product taste better.
What is umami? Look below!