| Microencapsulation technology, a new-style method to embed solid liquid or gas to form micro particles with range of diameter from 101-103micron, has developed increasingly in past several decades. Compared to other traditional methods applied in the process of micro-encapsulation, spray-drying technique has competitive advantages including mild operating conditions,low cost and fair average quality of production.Grape seed proanthocyanidin extract (GSPE) is compounds of polyphenol, Oligomerization proanthocyanidin is water-soluble substance which is easily absorbed. It has severals biological activities such as antioxidantion, heart protectingand anti-mutation. So it has been widely used in food, medicine and cosmetic industry. Recently, it becomes a common raw material that be used to produce supplementfood. Because proanthocyanidin was easily influencede by oxygen, light, andacid .Besides poor liposolubility also confines the utilization.In order to make full use of GSPE, enlarge its application fields and improve its liposolubility,micro-encapsulation technology of GSPE bys pray-drying was investigated in this paper, the main results were obtained as follows:(1) The method of preparing GSPE microencapsulation by spray-drying was confirmed. This method was decided through the results of judgement on the microencapsulated GSPE by sensory organ quality, and the factors of feasibility and economy about the test were considered at the same time.(2) The wall materials were selected according to the results of encapsulation and economy,and the suitable materials for wall were determined. We discussed the common use wall materials in food industry,and the optimum wall was selected as follow: PEG,EC and CAP as the main materials, lecithin as composite emulsifier.(3) The dosage of the emulsifiers and the condition of the emulsifying technique were obtained. On basis of the single factor test, the optimum wall material composition was obtained by orthogenesis test in the preparation of GSPE microcapsules by spray-drying. The result was as follows: the ratio of PEG to EC to CAP is 0.8:1:0.1,the ratio of core to wail is 0.6:1, the content of emulsifier is 0. 50%, the concentration of emulsion is 20%. The microencapsulating efficiency of GSPE was about 93% on the condition above.(4)The optimum spray-drying technological parameters were investigated. The result of the orthogenesis test indicates that the optimum parameters about microencapsulated GSPE techniques were as follows: feed temperature was about 50-60℃, feed solid concentration was 20%, feed flow rate was 45mL/min, the frequency of homogenizing was 3, homogenizing pressure was 35MPa, temperatures of inlet wind and outlet wind were 160℃and 85℃, respectively. The microencapsulating efficiency of GSPE was about 94.5% on the condition above.(5) The characters of microcapsuled GSPE prepared by spray drying technic was evaluated. The preparation of GSPE showed milkiness in colour, and the content of moisture , the density, the solubility and the average diameter were about 2. 88%, 0. 75g/cm3 91.5% and 15. 2μm, respectively.It provided with certain dispersion control ability. According to the result of DSC analysis, glass transition was not seen below 40℃.The product showed higher stability in the stability assay.
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