Modified corn cob as novel fragrance carrier via lignocellulose removal

Abstract

In this study, three kinds of modified corn cobs (MRC) were developed based on the principle of removing cellulose, hemicellulose and lignin from raw corn cobs (RC) to load fragrance and improve its storage stability. The three MRCs exhibited high loading capacity for fragrance (1.37–1.71 g/g), which was 4–5 times higher than that of the original one. The loading and protective function of HCl-H₂O₂-MRC showed significant improvement in the storage stability of menthol fragrance, with only 31.75 % content loss during the storage. Scanning electron microscope and Brunauer-Emmett-Teller analysis indicated that the surface and internal structure of the MRC was altered to achieve greater porosity and pore volume, that the specific surface area of HCl-H₂O₂-MRC (0.1231 cm³/g) was 20 times that of RC. The Fourier transform infrared spectroscopy results proved that the number of hydrogen bonding sites was increased without introducing new functional groups, and the cellulose framework was greater exposed through modification. The results of thermogravimetric analysis demonstrated that the MRC possessed stable thermal properties and significantly prolonged the heat release time without changing the peak release temperature of fragrance. All the three MRCs followed the first-order equation with their release rate constants (k) of 0.0855, 0.1250, and 0.0685 respectively, indicating a constant decay in fragrance evaporation rate that gradually decreased over time. The results of this work suggested that modified corn cobs could be a promising green fragrance carrier.