Differential volatile-omics analysis for tamarind (Tamarindus indica L.) and aroma-active compounds identification via DMU-SPME-GC-MS method.

The dual-mode unity solid-phase microextraction (DMU-SPME) method was assessed and optimized using tamarind concentrate juice (TCJ) to improve the extraction of aroma-active compounds. DMU-SPME was systematically compared with conventional extraction techniques, including headspace solid-phase microextraction (HS-SPME) and solvent-assisted flavor evaporation (SAFE). GC-MS analysis revealed that DMU-SPME identified 84 volatile compounds, providing a more comprehensive volatile profile of tamarind than HS-SPME or SAFE. Aroma Extract Dilution Analysis (AEDA) further revealed that DMU-SPME detected more aroma-active compounds with higher FD values, such as benzoic acid, octanoic acid, α-terpineol, 2,3-dihydro-2,2,6-trimethylbenzaldehyde and decanal, which contributed to the sour, sweet, woody, herbal and floral notes of tamarind. The optimized DMU-SPME was then applied to compare green and ripe tamarind, revealing differential compounds such as benzene-acetaldehyde, 5-hydroxymethylfurfural, sec-butylamine, p-cymene and octanal. Overall, DMU-SPME demonstrated superior performance for comprehensive volatile extraction and ripeness evaluation, establishing it as a reliable and solvent-free technique for food flavor research.