Development of vanillin/ß-cyclodexterin inclusion microcapsules using flax seed gum-rice bran protein complex coacervates.

Encapsulation of vanillin through ß-cyclodexterin inclusion complex coacervates (ß-CD-IC) was developed to achieve higher thermal stability and controlled release of vanillin. The effect of protein to polysaccharide (Pr:Ps) ratio and core (Vanillin/ß-CD-IC) to wall (coacervate) ratio on the vanillin encapsulation as well as thermal, microstructural and physical characteristics of microcapsules were investigated. Microcapsules had particle size ranging from 0.75 to 4.5 µm with negative surface charge and narrow size distribution. Although particle size and encapsulation efficiency were increased by increasing the Pr:Ps ratio and core to wall ratio, the zeta-potential decreased. Vanillin/ß-cyclodexterin loaded microcapsules had the maximum encapsulation efficiency about 85% at core to wall ratio of 1:3 and Pr:Ps ratio of 9:1. Structural studies by Fourier-transform infrared spectroscopy (FTIR) indicated the entrapment of encapsulant and X-Ray diffraction data and scanning electron microscopy (SEM) images showed that microcapsules have amorphous structure with soft surface. Furthermore, FTIR results indicated the formation of vanillin/ß-cyclodextrin inclusion is the result of chemical interactions, but physical interaction between core and shell leads to encapsulate vanillin/ß-cyclodextrin inclusion in rice bran protein-flaxseed gum (RBP-FG) coacervates. Microencapsulation increased the vanillin thermostability and its shelf life. Therefore, it is possible to increase thermal stability of vanillin against environmental conditions.

Production and characterization of vitamin D3 loaded starch nanoparticles: effect of amylose to amylopectin ratio and sonication parameters.

Two types of starches with different amylose to amylopectin ratios were used for the production of vitamin D3 loaded nanoparticles and effects of starch type, sonication time and temperature on physicochemical properties of nanocarriers were investigated. Both high amylose corn and potato starches nanocarriers had granular structure with particle size ranging from 32.04 to 99.2 nm and the encapsulation efficiency ranging from 22.34 to 94.8%. The results showed that potato starch nanoparticles had larger size, higher zeta potential, encapsulation efficiency and encapsulation load and lower polydispersity index values in comparison to high amylose corn starch nanoparticle. Increase in sonication time reduced the size of nanoparticles in both starch types and decreasing temperature led to reduction of particle size and increase of zeta potential. Physicochemical features of nanocarriers were analyzed by Fourier transform-infrared spectroscopy, X-ray diffraction and differential scanning calorimetry. The results indicated that vitamin D3 is well incorporated in carriers and ultrasonic treatment led to increase of hydrocarbon chain that resulted in van der Waals and hydrogen bonds of vitamin D3 with the potato starch and greater thermal stability.