New Technology Of Tea Polysaccharide Extraction And Research And Development Of New Products

Tea polysaccharides（TPS）obtained by y separation and purification from tea leaves,stems,or other by-products of tea.The crude tea polysaccharide is a mixed polysaccharide containing substances such as polysaccharides,proteins and mineral elements.In this study,oolong tea（Anxi Tieguanyin）and black tea（Fuding Dabai tea）were used as raw materials.Two new processes,eutectic solvent extraction and subcritical water extraction,were used.On the basis of single factor experiments,Box-Behnken（BBD）was used.The combination of experimental design and Response Surface Methodology（RSM）optimizes the two new process conditions for tea polysaccharide extraction,and obtains mathematical model fitting and regression equations,and analyzes and predicts the model test through Design Expert 10.0.0 software Verification to determine the best process conditions for tea polysaccharide extraction.The macroporous resin was used to purify tea polysaccharides,and the scavenging abilities of DPPH and hydroxyl radicals were compared to evaluate the antioxidant activity of pure tea polysaccharides.Using pure tea polysaccharide as raw material,tea polysaccharide lozenges were developed.This study provides a scientific basis for exploring new and non-toxic green tea polysaccharide extraction process and application.The experimental conclusion is as follows:1.New technology of oolong tea polysaccharide extractionUsing oolong tea as raw material,according to the characteristics of tea polysaccharides,green,non-toxic and efficient eutectic solvent and subcritical water extraction parameters were designed,and the conventional water extraction method was used as a control to study the new eutectic solvent method and subcritical method extraction process The efficiency of oolong tea polysaccharides.The experiment showed that:6 kinds of green,non-toxic and efficient eutectic solvents were prepared,and the eutectic solvent composed of betaine-1,3 butanediol was the most suitable for the extraction of oolong tea polysaccharides.According to the design principle of Box-Behnken Design’s central combination test in the response surface analysis method,through regression analysis,the second-order polynomials of the extraction yield and extraction time（A）,extraction temperature（B）,and water content（C）of oolong tea polysaccharide Regression model:Y=6.752+0.105A+0.145B+0.37C-0.015AB-0.08AC+0.15 BC0.5785A²-0.6835B²-0.5185C².The analysis of variance showed that the regression equation of the model was extremely significant（p<0.01）,the misfit term was not significant（p=0.1487>0.05）,the multivariate correlation coefficient R²=0.9839>95%,and the correction decision coefficient R_Adj²=96.31%.The optimal extraction conditions are as follows:extraction time 81 min,extraction temperature 61°C,water content 84%,solid-liquid ratio 1:20g/m L,and the average extraction rate of tea polysaccharide is 6.91±0.21%,which is not significantly different from the predicted value（p>0.05）,which is 49.24%higher than conventional water extraction methods.According to the design principle of Box-Behnken Design’s central combination test in response surface analysis method,through regression analysis,a quadratic polynomial regression model for extracting oolong tea polysaccharides from subcritical water is obtained:Y=11.16+0.17A-0.17B-0.24C-0.025AB-0.033AC-0.11BC0.47A²-1.03B²-0.94C².It can be seen from the analysis of variance of the regression model that the regression equation of the model is extremely significant（p<0.01）,the misfit term is not significant（p=0.1906>0.05）,the multivariate correlation coefficient R²=0.9893>95%,the correction decision coefficient R_Adj²=97.55%.The optimal extraction conditions are as follows:subcritical time 40 min,subcritical temperature 139℃,solid-liquid ratio 29g/m L,the average extraction rate of tea polysaccharide is 10.97±0.35%,and there is no significant difference from the predicted value（p>0.05）,Compared with conventional water extraction,it increased by 136.93%.For the extraction of oolong tea polysaccharides,the subcritical extraction method is superior to the eutectic solvent method,and the eutectic solvent method is superior to the conventional water extraction method.2.New technology for black tea polysaccharide extractionUsing black tea as a raw material,according to the characteristics of tea polysaccharides,six green,environmentally friendly and efficient eutectic solvents were designed,and conventional water extraction was used as a control group.The two extracted methods were compared by the eutectic solvent method and the subcritical extraction method.Black tea polysaccharide.Six kinds of green,non-toxic and efficient eutectic solvents were prepared.Among them,the eutectic solvent composed of betaine-1,3butanediol was the most suitable for the extraction of black tea polysaccharides.According to the design principle of Box-Behnken Design’s central combination test in response surface analysis method,through regression analysis,a quadratic polynomial regression model of eutectic solvent extraction of black tea polysaccharides is obtained:The equation is as follows:Y=7.06+0.065A+0.071B-0.064C+0.017AB+0.0025AC-0.03BC-0.4A²-0.46B²-0.4C².According to the analysis of variance of the regression model,the regression equation of the model is extremely significant（p<0.01）,the misfit term is not significant（p=0.1839>0.05）,the multivariate correlation coefficient R²=0.9811>95%,and the correction decision coefficient R_Adj²=0.9567.The optimal extraction conditions are as follows:the extraction time is 102 min,the extraction temperature is 61°C,the water content is 49%,the solid-liquid ratio is 1:20/g m L,and the average extraction rate of black tea polysaccharide is 7.02±0.17%,which is not significantly different from the predicted value（p>0.05）,which is 55.31%higher than conventional water extraction.According to the design principle of Box-Behnken Design’s central combination test in response surface analysis method,a quadratic polynomial regression model for extracting black tea polysaccharides from subcritical water is obtained:quadratic polynomial regression model:Y=8.31+0.070A+0.0075B-0.12C-0.03AB+0.0001AC+0.0001BC-0.68A²-1.40B²-0.11C².It can be seen from the analysis of variance of the regression model that the regression equation of the model is extremely significant（p<0.01）,the misfit term is not significant（p=0.739>0.05）,the multivariate correlation coefficient R²=0.9985>95%,the correction decision coefficient R_Adj²=99.65%.The optimal extraction conditions are as follows:subcritical time77min,subcritical temperature137℃,solid-liquid ratio 34 g/m L,the average extraction rate of tea polysaccharide is 8.13±0.35%,which is not significantly different from the predicted value（p>0.05）,Compared with conventional water extraction,it increased by79.87%.For the extraction of black tea tea polysaccharides,the subcritical extraction method is superior to the eutectic solvent method,and the eutectic solvent method is superior to the conventional water extraction method.3.Tea polysaccharide purification,monosaccharide composition and physical and chemical properties analysisBy comparing AB-8,D101 and HPD500 resins,the crude polysaccharide extract from betaine-1,3 butanediol was decolorized and deproteinized.D101 resin had the highest decolorization effect,and the optimal dosage was 0.6g/m L,the decolorization rate is 18.27%,the protein removal rate is 38.06%,and the polysaccharide retention rate is78.78%.Therefore,D101 resin was used to purify the common water-extracted oolong tea polysaccharides,subcritically extracted oolong tea polysaccharides,conventional water-extracted black tea polysaccharides,and eutectic solvents.Extraction of black tea polysaccharides,subcritical extraction of black tea polysaccharides.Gas chromatography-mass spectrometry（GC-MS）was used to determine the monosaccharide composition of polysaccharides.The results showed that the six tea polysaccharides were composed of L-rhamnose,D-fucose,L-arabinose,and D-mannose Sugar,D-glucose,and D-galactose are composed of 6 monosaccharides,but their respective molar ratios are different.Among them,D-galactose,D-glucose,and L-arabinose are higher in content.L-rhamnose,D-Fucose and D-mannose are low.Analysis by ultraviolet and infrared spectroscopy showed that the six tea polysaccharides all have characteristic absorption peaks of polysaccharides,and the molecular structure contains proteins,all of which are glycoprotein complexes dominated by pyran rings.The surface morphology of the six tea polysaccharides was observed by electron microscopy scanning,and it was found that the surface of the tea polysaccharides showed different morphologies in different extraction methods of the same kind of tea leaves.The pores of tea polysaccharides extracted by conventional water are small,and after eutectic solvent extraction and subcritical water extraction,the pores of tea polysaccharides become larger.4.Antioxidant activity analysis of pure tea polysaccharidesThe biological activity of tea polysaccharides obtained from 6different extraction methods was evaluated using DPPH and hydroxyl radical scavenging rates.The determination of DPPH clearance rate showed that the IC₅₀ of oolong tea polysaccharide extracted by eutectic solvent was 0.147mg/m L,the IC₅₀ of subcritically extracted oolong tea polysaccharide was0.432mg/m L,the IC₅₀ of conventional water-drawn oolong tea was0.417mg/m L,and the IC₅₀ of Vc was 0.114mg/m L.The IC₅₀ of black tea polysaccharide extracted by eutectic solvent is 0.074mg/m L,the IC₅₀ of subcritically extracted black tea polysaccharide is 0.348mg/m L,the IC₅₀of conventional water-extracted black tea polysaccharide is 0.204mg/m L,and the IC₅₀ of Vc is 0.114mg/m L.The measurement of hydroxyl radical scavenging rate shows that the IC₅₀ of oolong tea polysaccharide extracted by eutectic solvent was0.261mg/m L,the IC₅₀ of subcritically extracted oolong tea polysaccharide was 0.673mg/m L,the IC₅₀ of conventional water-extracted oolong tea polysaccharide was 0.440mg/m L,and the IC₅₀ of Vc was0.237mg/m L.The IC₅₀ of black tea polysaccharide extracted by eutectic solvent is 0.313mg/m L,the IC₅₀ of subcritically extracted black tea polysaccharide is 0.383mg/m L,the IC₅₀ of conventional water-extracted black tea polysaccharide is 0.492mg/m L,and the IC₅₀ of Vc is0.237mg/m L.The black tea polysaccharide DPPH extracted by the eutectic solvent has the strongest antioxidant capacity,which is 63.72%higher than that of conventional water extraction.The black tea polysaccharide extracted by the eutectic solvent has the strongest antioxidant capacity,and has the highest antioxidant capacity,as compared with conventional water.Increased by 40.68%.It can be seen that tea polysaccharides can be used as potential antioxidants.5.Development of tea polysaccharide tabletsUsing tea polysaccharide as the main raw material,pineapple powder,raw powder,mint ice,and aspartame as auxiliary materials,and magnesium stearate as a lubricant,the tea polysaccharide lozenge was developed.Orthogonal experiments were used to analyze tea polysaccharides,raw powder,mint ice,and aspartame that affected the sensory quality of tea polysaccharide lozenges（3%）,raw powder（35%）,mint ice（1%）,aspartame（10%）,pineapple powder（50%）,magnesium stearate（1%）,wet with70%ethanol It is made of soft material,wet granulated,dried in an oven at 65℃,drying time is40-60min,single punched sheet.