In the sense that they contribute to umami taste, yes. But most commonly the nucleotides inosinate (from meat and fish) and guanylate (from dried mushrooms) are the other molecules that provide umami flavors.
I'm pretty sure the MSG disassociates into the sodium ion and the glutamate, since it's soluble in water. I only use the term MSG to refer to the additive when it's in the salt form in a dry jar.
Side note: it's really funny if you think about it, umami is basically just the taste of amino acids and nucleic acids, which presumably makes sense since the body uses them so much (beyond just making protein and DNA/RNA).
The umami flavor of cheese, especially hard cheeses, is incredibly under appreciated. And I'll never understand the popularity of pre-shredded cheese...
Umami is a lot more present that people recognize. I've built up an intuition for this over the years, and also sort of trained my tongue.
What we call umami is a subjective experience that has an underlying molecular cause, but it's complicated: more than one molecule contributes to the sensation, different foods have different molecules, many people can't recognize it on its own, etc.
The most easily recognized umami tastes seem to come from hydrolyzed soy protein and yeast extracts- both are added to tons of food. The canonical example is Doritos, which are a masterpiece of modern food industrial optimization. Doritos are mostly corn, but they also add whey (cheese derived umami), MSG (molecular, isolated glutamate in salt form), buttermilk (multiple flavors including umami), romano cheese (more umami!), tomato powder (umami), inositate (umami). It's basically an umami bomb.
From what I can tell, the best umami flavors come from a combination of several different molecules combined with some salt. the combination seems to potentiate the flavor significantly. You can also saturate out your receptors- if you drink a highly concentrated broth, you'll see there's some upper limit to the amount of umami you can taste and after that, additional aminos are just wasted.
> I'll never understand the popularity of pre-shredded cheese...
If spending too much time in eve online taught me anything, it's that convenience is worth money. People are inherently lazy, and there's plenty of ways to exploit that.
The next level of pre-grated cheese is frozen pizza, for example.
Its not laziness, its just a matter of priority. Like playing eve online, or doing nothing.
But really, there is what feels like an ever increasing list of 'stuff to do, things to attend', and preparing food (and sleep) are obvious time sinks to reduce, and of course people are willing and increasingly able to pay.
A recent survey (forget the link, sorry), listed time spend on food preparation / cooking nowadays as averaging out on just 28 minutes daily. Around 1980, this was still around 2.5 hours. I believe context is UK.
I easily spend 3 hours daily, because especially with a little kid I just think it is important to do, but I do also feel the weight of it.
Me either, but a relative who worked in processed foods told me the reason it exists isn't just lazy consumers, it's made from the oddly-shaped (by supermarket standards) offcuts that they can't sell otherwise.