The Preparation Technology And Stability Evaluation Of High Contentβ-carotene Microcapsule

Beta carotene has the function ofsupplementVA,improve eyesight,enhancing the nutrition,increasing immunization,preventing cancer and so on, butit contains more unsaturated double bond, its chemical property active. Beta carotene easy oxidative degradation when it is susceptible tolight, heat, oxygen,to a large extenthinderits application in real life.In order to improve the stability and promote its practical application in the market,the experiment use spray drying method preparation of beta carotene microcapsules.Integrate the embedding efficiency and stability protection performance two indicators of microcapsule products, studying wall material selection and component ratio, amount of emulsifier, concentration of the wall material, ratio of core to wallmaterial on the influence of beta carotene microcapsules.Optimized stable high content of beta carotene microcapsule preparation technology parameters: the wall materials of soybean protein isolated, modified starch and malt dextrin(6:6.5:7.5), wall material concentration of 20%, core material to wall material of 1:3, without emulsifier, high pressure homogeneous of 30 Mpa cycle three times, the spray pressure of 0.2 Mpa,feed speedof 1000 ml/h and inlet air temperature of 140 ℃.The preparation of the monolayer beta carotene microcapsule embedding efficiency is 93.53% and beta carotene highest content is 10.48%. Beta carotene microcapsule embedding effect is good and productproperty is stable,which provides a reference for late industrialization.According to the optimum technological parameters, prepare microcapsule product and comprehensive analyse microcapsule products quality.Microcapsule product is uniform powder, red color is pure, not easy to damp agglomerate, no pigment leak, no leakage of oil, has a slight beta-carotene fragrant smell, dissolves in water easily and aqueous emulsion is red bysensory evaluation. Physical and chemical show that product highest embedding rate is 93.53%,and the highest content of up to 10.48%, moisture content is low, liquidity is good.Through testing particle size distribution of product, top collection product particle size most is the range of 5- 20 um, low collection product particle size most is the range of 10-100 um. By SEM testing product ultrastructure, shows that the microcapsule has relatively smooth surface, no holes and cracks, no "overseas" phase, only has a small amount of small particle size of microcapsules adhesion on the surface of big particle size of microcapsules, but part of the surface of the microcapsules has collapse phenomenon. Finally, by differential scanning heat detection, the glass transition temperature of the microcapsule product closes to 40 ℃.Through disposing microcapsule product in different environmental such as temperature, humidity and light, assess products’ protectionstability property.Comparing different humidity influence on retention rate of beta carotene crystal powder and microcapsule products, the microcapsule products at lower humidity of 45%, its half-life period is extend to 111.8 days, is 7 times to crystal, has played a very good protection effect.Contrast light and dark conditions on retention rate of beta carotene crystal powder and the microcapsule products, microcapsule products can well protect the core material and reduce the effect of light on beta carotene.Comparison of different temperature effect on retention rate of beta carotene crystal powder and microcapsule products, under the condition of below the glass transition temperature, the half-life of microcapsule products up to 128 days or more, is the half-life of beta carotene crystal powder expanded more than 15 times, has played a very good protection effect.