Abstract:Electronic nose and headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) were used to determine and analyze volatile flavor substances in the preparation of packaged tofu after raw and cooked pulping processes. A total of 59 compounds were detected in two samples, including 15 alcohols, 9 esters, 2 alkanes, 18 aldehydes, 11 ketones, 2 phenols, and 2 other compounds. The results of the relative odor activity value (ROAV) showed that there were 23 key flavor substances (ROAV ≥ 1) in packaged tofu. Notably among these were, N-hexyl aldehyde, heptanal, n-octanal, 2-heptenal, trans-2-octanal, capric aldehyde, (E,E)-2, 4-nonadienal, 2-undecylenal, trans-2, 4-decandienal, n-amyl alcohol, 1-octane-3-ol, 1-heptanol, 1-nonanol, 2-octanone, 2-nonanone and 2-n-amylfuran. These characteristic volatile substances are shared by both kinds of wrapped tofu, contributing significantly to their unique flavor. Trans-2-decenal and 2-heptanone were identified as key flavor substances in cooked pulp samples, while nonanal, 1-nonanol, ethyl n-caproate and 2-phenethyl caproate were key flavor substances in raw pulp samples. Understanding the flavor components of bean curd generated by cooked and raw pulping processes has significant implications for the actual production of bean curd.