How to change the chirality of amino acids? Is it possible to change the chirality of the amino acids? I understand such a process is called "stereoinversion".

Take a levorotatory amino acid and turn it into it's dextrorotatory counterpart (enantiomer, optical isomer).

Anyone tried to do that? Can a high temperature change the chirality of an amino acid for example?

Racemization is good enough for me. Changing the chirality of just a small amount of the total amino acids in the sample is good enough.
Temperature is likely not going to work. To racemise something that has a chiral center, you need to break a bond: if you want to supply that much energy by heating, you are going to fry your molecule.

The easiest things to do are usually extraction of an acidic proton with a strong base, formation of a double bond involving the formerly chiral carbon, and then you go back to the initial form, but obtaining a racemate because the attack on the two sides of the double bond is equally likely.