The racemization rate of selenomethionine and methionine in yeast at 100 degrees C and neutral pH.

The rate of racemization of selenomethionine in yeast at 100 degrees C and pH 7.4 was determined using gas chromatography to separate the trifluoroacetyl-L-prolyl-D,L-selenomethionine methyl esters. The racemization half-life (i.e., the time required to attain a D/L ratio of 0.33) of selenomethionine was found to be similar to that of methionine and have a value of 19-20 days.