Impact of harvest periods of Sichuan pepper on Sichuan pepper-flavoured chicken using electronic nose, electronic tongue, and chromatography

This study compared Sichuan pepper harvested at five stages (July–September) for preparing Sichuan pepper-flavoured chicken. Electronic nose and tongue analyses separated the control from peppered samples and further distinguished early (July–august) from late (September) harvests; September pepper produced stronger odour, higher umami and sourness, and lower bitterness. GC–IMS fingerprints revealed harvest-dependent shifts in volatile profiles, and OPLS-DA (VIP > 1) highlighted limonene-D/M (highest VIP), terpinolene, myrcene, sec-butanol, isobutyl acetate-D, and terpinyl acetate-D/M as key markers. HS–GC–MS detected 68 volatiles; OPLS-DA markers (VIP > 1) included 3-penten-2-ol (highest VIP), β-pinene, limonene, phellandrene, linalyl acetate, and eucalyptol, while α-pinene varied significantly with harvest period. Overall, later harvest increased terpene/ester abundance and most effectively enhanced the characteristic flavour of Sichuan pepper-flavoured chicken.