VOLATILE COMPOUNDS GENERATED FROM THERMAL REACTION OF METHIONINE AND METHIONINE SULFOXIDE WITH OR WITHOUT GLUCOSE

摘要

Methionine and methionine sulfoxide were mixed with or without glucose in distilled water, individually. These solutions were heated in closed sample cylinders at 180 degrees C for 1 h. The volatile compounds generated were extracted using methylene chloride and analyzed by GC and GC-MS. Pyrazine compounds, especially 2,5-dimethyl-, 2-ethyl-5-methyl-, trimethyl-, and methylpyrazines were the predominant compounds among those generated from thermal interactions of glucose and methionine or methionine sulfoxide. The formation of methional or those compounds derived from methional was found to be more favorable from the thermal degradation of methionine, whereas the formation of dimethyl polysulfides, especially dimethyl disulfide and dimethyl trisulfide, was found to be more favourable from the thermal degradation of methionine sulfoxide. Glucose was found to have a catalytic effect on the formation of volatile compounds from the thermal degradation of methionine or methionine sulfoxide.