Pore-size-tunable SBA-15 mesoporous silica for sustained release and flavoring performance of peppermint essential oil

Peppermint essential oil (PEO), a multicomponent volatile oil from Mentha × piperita L ., is highly volatile, limiting stable flavor delivery in cigarette filters. Three SBA-15 mesoporous silicas with BJH pore diameters of 2.95, 7.78, and 9.59 nm were prepared to investigate pore-size effects on PEO loading, retention, and release. All carriers retained a two-dimensional hexagonally ordered mesostructure. After loading, N₂-accessible specific surface area and pore volume decreased markedly, while FT-IR, XPS, and TGA further confirmed incorporation of organic components. At a carrier/PEO mass ratio of 1:15, SBA-15–2 (7.78 nm) showed the highest PEO loading capacity (0.844 g g −1 ) and favorable stability and sustained-release performance. Sequential ethanol washing and ultrasound-assisted extraction showed that PEO-SBA-15–3 had the highest first-step recovery proportion, whereas PEO-SBA-15–1 had the highest subsequent extraction proportion. HS-SPME-GC-MS showed changes in relative headspace volatile profiles after PEO loading and release under the specified analytical conditions. Although major volatile PEO components were smaller than all three mesopore diameters, smaller pores increased resistance to molecular entry and intrapore migration, whereas larger pores provided weaker retention; the 7.78 nm pore size showed a more balanced overall performance. In cigarette filters, PEO-SBA-15–2 also showed a relatively balanced sensory profile across mint-character clarity, cooling persistence, and irritation, while conventional mainstream smoke parameters, including TPM, tar, nicotine, and CO, changed to varying degrees. This study provides experimental support for pore-size design of mesoporous carriers for plant-derived essential oils and their application in sustained flavor delivery.