Combined modification of starch nanofiber membranes via organic acids and glutaraldehyde crosslinking for selective adsorption of flavor compounds.

Starch-based nanofiber membranes prepared by electrospinning show potential for food flavor adsorption due to their porous structure. However, their application is limited by poor hydrophobicity, weak mechanical properties, and insufficient selective adsorption. In this study, octenylsuccinylated starch (OSS) and pullulan (PUL) were combined with citric acid, tannic acid (TA), and gallic acid to fabricate nanofiber membranes via electrospinning. Combined modification was achieved through glutaraldehyde (GTA) crosslinking, and the selective adsorption mechanism for flavor compounds in oyster enzymatic hydrolysate was further investigated. GTA-crosslinked TA-modified nanofiber membranes (OSS-PUL-TA-G) showed excellent selective adsorption performance. Following adsorption by the OSS-PUL-TA-G, the peak intensities of off-flavor compounds (butanal and 2-methylbutanal) in oyster enzymatic hydrolysate were significantly reduced, while desirable flavor compounds (2-butylfuran and pentyl butanoate) were effectively retained. X-ray photoelectron spectroscopy and correlation analysis indicated that aldehyde adsorption correlated with C1s (C-OH) content (p ≤ 0.05), while acid adsorption correlated with C1s (O-C-O/C=O) (p ≤ 0.05). OSS-PUL-TA-G also exhibited improved physicochemical properties, with water contact angle increasing from 23.66° to 48.71° and tensile strength from 1.86 MPa to 2.85 MPa. This work provides a theoretical basis for precise flavor regulation of aquatic products.