Characterization of key aroma compounds in pixian broad bean paste through the molecular sensory science technique

The Pixian broad bean paste (PBBP) is widely welcomed by consumers in China due to its unique aroma. The objective of this study was to characterize the key aroma of PBBP. The aromas of PBBP were fractionated by normal phase-liquid chromatography (NP–LC) and detected and identified by gas chromatography-olfactory (GC–O) coupled with gas chromatography-mass spectrometry (GC–MS), and quantitated by stir bar sorptive extraction (SBSE). The results showed that 58 aroma-active compounds were identified in PBBP, of which acids and phenolics had the highest concentration, and 39 odorants were demonstrated as important odorants. Besides, aroma recombination tests and statistical analysis showed that the original PBBP and recombinant have no significant difference in sweat/sour, roasted, and floral attributes, proving that this study successfully simulated the typical aroma of PBBP. The omission tests demonstrated 4-ethylguaiacol and 4-vinylguaiacol as the key odorants and revealed the significance of sotolon, 4-hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF), the entire class of phenolics, and the entire class of acids, particularly acetic acid, 3-methylbutanoic acid, 4-methylpentanoic acid may have a synergistic effect, for the overall aroma of the PBBP.