Discrimination of different varieties of rice in Wuchang area based on E-nose and HS-SPME-GC-O-MS

This study aimed to discriminate between different varieties of rice from the Wuchang region using a combination of electronic nose (E-nose), headspace solid-phase microextraction-gas chromatography-olfactometry-mass spectrometry (HS-SPME-GC-O-MS), and chemometric analysis. Six rice varieties (Wuyoudao No. 4 (WC54), Longyang No. 11 (LY11), ZhongKefa No. 5 (ZKF5), Dongnong No. 425 (DN425), Longyang No. 16 (LY16) and Suijing No. 18 (SJ18)) were analyzed to identify key volatile compounds and aroma-active substances. The electronic nose provided initial differentiation, particularly by the 5 th, 14 th, and 11 th sensors), which showed significant differences in their response strength between ZKF5 and LY16. Furthermore, 148 differential volatile compounds (VIP > 1) were identified by HS-SPME-GC-MS, and aldehydes and alkanes were the most significant contributors to the aroma profiles. Meanwhile, orthogonal partial least squares-discriminant analysis (OPLS-DA) further confirmed the distinctiveness of each rice variety based on their volatile compounds (R²Y = 0.991, Q² = 0.900). Additionally, GC-O analysis revealed 36 aroma-active compounds, with WC54 exhibiting the highest aroma intensity, characterized by fruity and creamy notes. The study successfully differentiated WC54 from other varieties, providing a robust method for protecting geographical indication products and ensuring consumer rights.