Stduy On The Preparation Technology Of Stachyose From Stachys Sieboldii Miq.

Stachyose is a natural occurring functional oligosaccharide, with a clear structure, high stability, low sweetness and calories. It possessed function of promoting the proliferation of intestinal bifidobacteria and it is difficult to digest. Because of its various physiological advantages, nowadays stachyose demand has grown increasingly in the world market.This study focuses on the Chinese artichoke (Stachys sieboldii Miq.) as the raw material (stachyose content 10%-15%) to investigation the industrial statchyose production. The study also focuses on the relationship between the stachyose and its source raw material.(1)The qualitative and quantitative determination of stachyose was studied by Thin Layer Chromatography (TLC) and High Performance Liquid Chromatography (HPLC). The optimum conditions was established: In the method of TLC selected ethyl acetate/methanol/water/acetic acid (3:2:1:2) as the developing agent, and choose diphenylamine-aniline-phosphate as the reagent, under this condition, Rf value of stachyose is 0.47, with yellow spot, clear and well separated from other sugars. HPLC with the refractive index detector (RID), use Kromasil NH₂ column, set mobile phase of acetonitrile/water (55/45,v/v), column temperature 30℃, the flow rate 1.0 mL/min. The results showed that the stachyose peak have great symmetry, short time (9.5 min), and can be baseline separated from other components.(2)The extraction of stachyose was carried out by homogenization of fresh artichoke, and the optimum parameters were: liquid ratio 1:20(w/v), speed 10000 r·min-1, homogenate time 2 min. Base on the conditions above, the extraction rate of stachyose reached 91.62 %. The method of homogenate extraction can not only cause the material crushing and effective components extraction simultaneously, but also have the advantages of easy operation. Low cost of this raw material could be an advantage for the extraction of stachyose at industrial level.(3)Decolorization experiments were conducted through the selection of proper resin for removing the coloring matters from stachyose extracts. The decolorization process was optimized and the selected characteristics conditions were: AB-8 resin, pH 5.0, temperature 30℃, under these conditions, the decolorization rate was 86.7% and the retention rate of stachyose reached 83.4%. At the flow rate of 1.5 BV/h, this resin can handled 3 BV liquid and keep the decolorization rate more than 80%.(4)The conditions of isolated and purified stachyose were studied and the best techniques were confirmed as follows: ultrafiltration to remove proteins, reverse osmosis for concentrate efficiently, precipitated stachyose with ethanol and use the column with activated carbon sugar to get high purity stachyose. Results showed that the optimization parameters were: ultrafiltration at room temperature to maintain the inlet pressure 0.5 MPa, the outlet pressure 0.4 MPa, feed temperature 45℃and pH 6.0, and the stachyose transmission was 81.3% and stachyose purity can reached 84.07%. When the reverse osmosis concentration to maintain the inlet pressure 0.6 MPa, the outlet pressure 0.5 MPa, feed temperature 30℃and pH6.0, the volume concentration ratio (VCR) is 4. Selected 85% ethanol to precipitant stachyose, standing at 4℃to precipitation 24h, than centrifuge 10 min at 12000 r·min-1, collected sediments dried at 60℃and the stachyose solution purity reached 93.08% detected by HPLC. Finally, use the column with activated carbon sugar to absorb stachyose, when the eluent concentration of ethanol in 10%, stachyose can be eluted. By spray drying we can get stachyose white powder with purity of 96.1%.(5)Develop product conducted for stachyose. Take stachyose, the powder of Bifidobacterium and Lactobacillus, Calcium carbonate and VD3 as the main ingredients of a kind of stachyose chewable tablet with the function of Calcium supplement and regulation of intestinal microflora.(6)In addition, in order to maintain the continuity of industrial production cycle, the storage of artichoke were investigated. The results showed that materials stored in different temperature and humidity environment have the different plant physiological responses, texture changes and stachyose content, the results indicated that under the temperature of 0℃, humidity of 40%-60%, plant have a low self-metabolism and the stachyose have a high retention rate. Drying of raw materials also were compared, the results showed that the combination of microwave drying and hot air drying had good drying effect, and the optimization parameters were: air drying (temperature 80℃, wind speed 3 m/s), Water transfer point was 50%, microwave power 600 w dried to moisture content below 3%, the retention rate of stachyose can reached 85%. This research results will improve the quality and storage properties of the raw material, provides theoretical basis for industrial continuous production.