Ultra‐Stable Y Zeolite as a Superior Host for Long‐Term Retention and Controlled Release of Vanillin

ABSTRACT Encapsulation of fragrances within porous materials is an effective strategy to preserve aromatic compounds and control their release. This study evaluates Faujasite‐type zeolites (NaY and Ultrastable Y/USY) as low‐cost carriers for vanillin encapsulation. Vanillin was incorporated via conventional wet impregnation, and the composites (Van@NaY and Van@USY) were characterized using FTIR, SEM, TGA, BET and GC‐FID. The long‐term release behaviour was evaluated under accelerated ageing conditions, while fragrance performance was assessed by a trained sensory panel. The results demonstrated that the larger pore volume, higher specific surface area and improved thermal stability of USY, resulting from its higher silica‐to‐alumina ratio, significantly enhanced vanillin encapsulation. GC‐FID analysis showed a loading capacity of 14.41 wt% for USY, approximately 1.5 times more than that obtained with NaY. BET analysis further confirmed successful pore filling, with an effective pore volume occupation of 18.7 wt%. TGA measurements revealed a cumulative thermal release of 20.5% for USY compared with 10.98% for NaY under accelerated ageing conditions. NaY exhibited a lower cumulative release, which is related to stronger host–guest interactions that restrict molecular mobility and limit fragrance availability. In contrast, USY achieved a more favourable balance between loading capacity, retention and sustained molecular release. Sensory evaluation further demonstrated that USY maintained the initial fragrance intensity while providing prolonged odour perception on treated fabrics throughout the storage period. Overall, this study establishes a clear structure–property relationship between the physicochemical characteristics of FAU‐type zeolites and their fragrance delivery performance. The combined analytical and sensory results identify USY as a promising inorganic carrier for advanced slow‐release fragrance systems and provide valuable design principles for developing zeolite‐based delivery platforms for volatile aroma compounds in household and personal care products.