VOLATILE COMPOUNDS PRODUCED FROM PEANUT OIL HEATED WITH DIFFERENT AMOUNTS OF CYSTEINE

Volatile compounds produced in the headspace of peanut oil heated with cysteine (0.5-10.0 g) at 200 degrees C for 5 h were collected by a si multaneous purging and solvent extraction apparatus. Volatiles in the extracts were analyzed by gas chromatography (GC) and gas chromatograp hy/mass spectrometry (GC/MS). Ninety-eight compounds were positively i dentified among over 150 gas chromatographic peaks. The majority of th ese were sulfur-containing compounds such as thiophenes, thiazoles, th iazolines, thiazolidines, and cyclic polysulfides. The two most abunda nt sulfur-containing compounds were 2-methylthiazolidine and 2-methyl- 2-thiazoline. Decarboxylation of cysteine at high temperatures and sub sequent reaction with aldehydes was proposed as a formation mechanism of both 2-alkylthiazolidines and 2-alkyl-2-thiazolines.