Background The precise volatile compounds accountable for the characteristic scent of the wheat aroma were presently unidentified. Given the prominent manifestation of “wheat aroma” in wheat cultivated in saline-alkali (SA) soil, five wheat varieties planted in saline-alkali soil and control soil (low saline-alkali soil) to create “rich-aroma” and “bland-aroma” samples, respectively. Methods The volatile profiles of these two groups of samples were analyzed using headspace solid-phase microextraction coupled with gas chromatographyed with gas chromathes-SPME-GC-MS), and differential characteristic volatile compounds between “rich-aroma” and “bland-aroma” samples were identified by combining paired t -tests, relative odor activity values (ROAVs), and molecular docking analysis. Results A total of 75 volatile compounds were identified using HS-SPME-GC-MS. Paired t -test result revealed that a significant increase ( p 0.05) in the peak areas and relative contents of limonene (109.74% increase), β-pinene ( 474.09% increase) contrasted with reduced butanoic acid (38.71% reduction) and (E,E)-3,5-octadien-2-one (16.05% reduction) in saline-alkali soil-cultivated wheats. Molecular docking demonstrated high binding energies (-4.25 kcal/mol) of limonene, β-pinene, and (E,E)-3,5-octadien-2-one to olfactory receptors, corroborated by relative odor activity values (ROAVs. 1). Conclusion Limonene, β-pinene and (E,E)-3,5-octadien-2-one are identified as possible saline-alkali soil-induced wheat aroma biomarkers, and offer theoretical insights for verificating wheat aroma. Identifying potential characteristic biomarkers in wheat under saline-alkali stress provides important theoretical insights for improving the flavor characteristics of wheat.
Zhang et al. (Wed,) studied this question.