Entrapment of peppermint oil using cellulose nanocrystals

Cellulose nanoparticles possess distinct advantages in delivery of different components because of their non-cytotoxicity and numerous surface hydroxyl groups. In this study, cellulose nanocrystals (CNC) were extracted from pistachio shell (PS). Alkali and bleaching treatments were performed to remove hemicellulose and lignin and purification of cellulose. Acid hydrolysis was performed in order to eliminate amorphous parts of cellulose and produce CNC. According to FE-SEM images, the diameter of CNCs was 36.6 ± 8.9 nm. Encapsulation of peppermint oil (PO) as a common aroma at different concentrations (10–50% V:W) was accomplished using CNC. CNC–PO with 50% encapsulant had the highest encapsulation efficiency and loading capacity. Release studies for all the samples were carried out in simulated saliva for 160 min and release kinetic behavior was evaluated by various mathematical models. FTIR analysis approved entrapment of PO using CNC by hydrogen bonding. XRD analysis showed that no remarkable changes in crystallinity of the CNC were occurred due to encapsulation. The results of this study indicated the possibility of production of CNC from PS and their application as the environmental friendly materials for delivery of aroma.