Isolation and characterization of microcrystalline cellulose from pomelo peel

In this study, cellulose from pomelo peel (PP-C) was isolated using alkaline hydrogen peroxide liquor extraction, and PP-C was further hydrolyzed by hydrochloric acid to yield microcrystalline cellulose (PP-MCC). Several analytical methods were used to determine the structural characteristics, crystalline behavior, morphological properties, thermal properties, and water/oil binding capacity of PP-C and PP-MCC. Fourier-transform infrared spectra and morphological analysis showed that the alkaline hydrogen peroxide treatment and acid hydrolysis successfully removed hemicellulose and lignin from pomelo peel fibers. Both PP-C and PP-MCC had only a cellulose I polymorph structure, and the crystallinity index of PP-MCC increased compared with that of PP-C. The degradation temperatures of PP-C and PP-MCC were approximately 257 °C and 280 °C, respectively. The water/oil binding capacity of PP-MCC was significantly higher than that of the commercial MCC. Our results thus suggested that PP-MCC might be suitable for use as a food stabilizer and pharmaceutical additive.