Effect of high concentrated sucrose on the stability of OSA-starch-based beta-carotene microcapsules

Beta-carotene (BC) microcapsules based on OSA-starch emulsions with different amount of sucrose were prepared to investigate the effects of sucrose on the physicochemical stability of BC microcapsules. BC loading amount, storage retention and particle size of water reconstituted microcapsules and emulsion before spray drying were studied. With the sucrose ratio increased in the wall material, the storage retention of the microcapsules powder and reconstituted powders increased as well. The free volume of the wall material decreased with increased sucrose ratio according to the SEM. Glass transition temperatures of the wall materials, the relative distribution of OSA-group in the powder determined by confocal Raman spectra microscope and the storage retention of BC of the water reconstituted microcapsules were also determined to interpret the mechanism of sucrose acting on the oxygen barrier effects of the wall materials. Phase separation was occurred in the high sucrose ratio group which probably the reason that the chemical stability of was increased. We also found that high ratio of sucrose can help to increase both physical and chemical stability of the water reconstituted microcapsules.

Automated summary

The study showed that increasing the sucrose ratio in the wall material led to higher storage retention of the microcapsules, decreased free volume of the wall material, potentially causing phase separation. A high sucrose ratio not only increased the physical stability of the microcapsules but also enhanced their chemical stability.