Objective: To investigate the difference of fatty acid content and types between red peanuts and white peanuts.
Methods: After being hydrolyzed, extracted, and methyl-esterificated, fatty acid in the sample were separated with the chromatographic column HP-88( 100 m × 0. 25 mm × 0. 20 μm) and analyzed by gas chromatography-mass spectrometry( GC-MS) method. Meanwhile, t-test and rank sum test will be carried on to analyze the determination results of fatty acid in both red and white peanuts growing in Shenzhen, Qingyuan and other four areas.
Results: The standard curves of fatty acid methyl ester hold good linearity( R~2> 0. 9980) in 0. 2- 10 mg / L, with the recovery between 92. 3% and 118. 8% and relative standard deviation( RSD) between 1. 64% and 7. 70%. Those two peanuts contained 21 fatty acids, such as oleic acid, linoleic acid, palmitic acid, stearic acid and behenic acid. The total fat content in peanuts were between 42. 5% and 50. 6%. After statistical analysis, the differences were not statistically significant.
Conclusion: The method can quickly and sensitively detect fatty acids inpeanuts. Same species and similar content of the fatty acids are in these two peanuts particularly.
Keywords: GC-MS; boron trifluoride method; fatty acid; peanut.