Effects of Different Cooking Methods on Volatile Flavor Compounds in Beef

In order to study the effects of different cooking methods (frying, steaming and boiling) on the volatile flavor compounds in beef, solid phase microextraction (SPME) combined with gas chromatography-mass spectrometry (GC-MS) was used to analyze the volatile flavor compounds of beef. GC-MS method was used to isolate and identify volatile flavor compounds in beef samples treated with different cooking methods. The results showed that 114 volatile flavor compounds were isolated and identified from beef samples treated by different cooking methods. The ways of cooking had significant effects on the volatile flavor compounds of beef, among which frying had the strongest effect, followed by steaming, and boiling had the slightest effect. A total of 61 compounds were detected in raw beef, while 59, 33 and 60 compounds were detected in steamed beef, fried beef and boiled beef, respectively. There were 14 volatile flavor compounds in common in raw beef, steamed beef, fried beef and boiled beef, which were listed in the following: 2-hydroxy-pentanoic acid methyl ester, hexanoic acid, dimethyl-silanediol, 1-octene-3-ol, 1-pentanol, nonanal, decanal, hexanal, tetradecanal, octanal, acetone, 2,3-octanedione, 3,7,11,15-tetramethylhexadiene-2-ene, methoxy-phenyl-oxime. The main volatile flavor compounds in raw beef were hexanoic acid ethyl ester and hexanoic acid (the relative contents were 16.15% and 11.17%, respectively). The main volatile flavor compounds in boiled beef were nonanal and 2, 3-octanedione (13.44% and 11.94%, respectively). The main volatile flavor compounds in steamed beef was hexanal (relative content was 44.89%). The main volatile flavor compounds in fried beef were formaldehyde, nonanal and hexanal (19.49%, 17.66% and 9.58%, respectively). The results of principal component analysis (PCA) showed that esters, hydrocarbons, acids and aldehydes might be the main factors affecting the differentiation of volatile flavor compounds in different samples. The results from this study would provide a technical reference for beef processing.