papaya - 30-1-2022 at 13:44
I was long looking for a way to distinguish between these two sodium glutamate forms, since food grade stuff is not explicitly telling which one you
get. It can be important sometimes as +-10% weight variation is too much sometimes,
No analytical procedure found, rather a very interesting paper was found that I would like to share with you: https://pubs.rsc.org/en/content/articlehtml/2021/cp/d1cp0473...
Long story short: monohydrate form CAN be dehydrated to anhydrous form by heating at 200°C, also at higher temperatures sodium pyroglutamate is
obtained, which is also good to know.
Tsjerk - 31-1-2022 at 05:00
Thanks, let us know what happens when you do this with the food grade stuff. My bet is on it being the monohydrate.
[Edited on 31-1-2022 by Tsjerk]
papaya - 31-1-2022 at 12:52
Yes may be some day I will perform a test, I suppose two things must be aligned for that to work.
First more or less accurate temperature control and maybe oil bath set at exactly 200C as we want to split only one molecule of water.
Next the mass loss is not so huge in that process when quantities are kept small. To be able to determine if there was water or not it might be just
enough to detect the condensation of vapor on colder glass sides - I imagine a long test tube filled with questionable MSG powder (bottom only) dipped
into hot oil and to see If some water starts to condense on higher sides.