Screening Of Modified Starch And Characterization Of Gelatin Starch Blending Films Based On Improvement Of Capsules

Gelatin capsules is one of most widely used traditional packaging materials in pharmaceutical and functional food industries, however, there are two major problems about gelatin capsule. Firstly, the price of gelatin exhibits soaring trends in the market. Secondly, ordinary capsule could not suit further multifunctional needs, such as controlled released properties or quick dissolution. Fortunately, the new pharmacodynamic assessment fully approved by the States Food and Drug administration (SFDA) created an opportunity for the development of novel gelatin capsule. So this paper focus on the blending modification of gelatin using5kinds of relatively low price modified starch (Modified starch). According to the basic capsular product procedure, firstly, the raw materials with high transparency, good retrogradation, film-forming capacities firstly were picked from13kinds of modified starch. Then the rheological properties of blending solutions were researched. After that, the blending solutions are casted to form film in order to evaluate the operability of making capsule. Finally, these basic researches could provide the parameters of improving capsular product. The main contents and results are shown as below:(1)Screen raw materials from13kinds of modified starchComprehensive assessments into, such as apparent viscosity, transparency, retrogradation, water-solublity and so on were taken into consideration. These properties are suitable for capsular industry. Then5kinds of candidates, which are pregelatinized sticky maize starch (B group), hydroxypropyl cross-linked sticky maize starch (D group), original maize starch (E group), pre-gelatinized original cassava flour starch (I group) and cross-linked esterified cassava starch (M group) were selected as candidates for further research.(2) Evaluate the5candidates by rheology and film-forming test.The viscometer shows that viscosities of B and I depended less on temperature and concentration. The steady flow behaviors of them present low zero-shear viscosity. B, M, and D exhibit better transparency. B, E, and D have higher mechanical strength. Therefore, it can be concluded that B and D matched needs for capsules production well.(3) Determine the properties of blending solutions and films.As the starch content increased, the viscosity decreased significantly at the low shear rate (1s-1lower), while at high shear rate (1s-1or higher), the shear stress of group B is significantly higher than that of group D. Meanwhile, the blend solution changed from the liquid nature to solid nature and temperature has little effect on the blended liquidIn this part, the Theological fluids were recorded and the structure of blending films was analysed. The transparency of blending films, made of B and gelatin at the ratio of5:22, reach the maximum of85.05%. The SEM graph showed a dense, smooth and tidy surface. Conversely, blending films made of D with gelatin have lower transparency and faster dissolving rate. These results show that B is more miscible with gelatin.