MSG stimulates specific receptors located in taste buds
such as the amino acid receptor T1R1/T1R3 or other glutamate
receptors like the metabotropic receptors (mGluR4 and
mGluR1) which induce the taste known as umami, one of
the five basic tastes (the word umami is a loanword
from Japanese; it is also referred to as "savory" or "meaty").
more about MSG
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