Research About Preparation Process Optimization And Gel Properties Of Inulin

The topics on Jerusalem artichoke as raw materials,purification of Jerusalem artichoke inulin,drying process optimization and ultrasonic extraction of inulin and inulin gel molecular weight of the rheological properties and texture properties were investigated.(1)Preparation of erusalem artichoke inulin and conditions of the optimization process.1)By HPLC with hot water extraction and ultrasonic extraction of the molecular weight of inulin.Of the two extraction methods derived molecular weight inulin obtained were as follows:2048(heat extraction extraction),591and342(ultrasonic extraction).It can be seen that the ultrasonic extraction of inulin altered the molecular weight,that ultrasonic extraction will change the molecular structure of inulin.2In the process of removing impurities,it found that removal protein was as an indicator value,when the temperature was between 70℃-80℃water bath for 20-40min favor higher protein removal,in which the temperature of the impurity the most pronounced.3)De Grey was a very important part of a purification process,the experiment selected 6 different types of ion exchange resin as the research object,respectively, calcium removal and decolorization rate were as index parameters,by comparing the experiments,it found that the 732 strong acid cation exchange resin had the best performance off ash,the optimal orthogonal optimization process,in condition of the adding amount 7.5g,extraction time,40 min,20℃temperature conditions,it can achieve the best results of off the ash,calcium ion removal rate was 85.26%,and the loss rate of 3.43% inulin. 4) Obtained macroporous D201-C had the best performance and lower decolorization rate of inulin loss,through the best orthogonal optimization process,when in addition level 8.0g,extraction time 100min,the temperature 20℃,it can achieve the best decolorization,the decolorization rate was 92.83%,and the loss rate of 1.69% inulin.5) To optimize the spray drying process,when the inlet air temperature was 180℃,the outlet temperature was 80℃,flow was 20ml/min,the yield of inulin was best for 29.15%.The effect of inlet pressure had no significant effect on drying.Freeze-dried inulin was higher,the destruction of low-Wen Duiju small loss of sugar is relatively small,was better than spray drying,but the cost was higher.6)Preparation of Jerusalem artichoke inulin after optimization process are as follows:Jerusalem artichoke tuberâ†'Cleaningâ†'Broken color protection(Vc color protection)â†'Enzyme inactivation in 100℃â†'Drying by 70℃â†'Sifted through a 40 mesh sieveâ†'Ultrasonic extractionâ†'Centrifugation(4000r/min,10min)â†'filterâ†'impurity(80℃water bath for 30min, lime,after adjusting pH value of 9.5-11.5 filter,and then adjust the pH value of phosphate5.0-7.5)â†'centrifugation (4000r/min,10min)â†'Filterâ†'De Grey (732 strong acid cation exchange resin,the resin addition level:7.5g / 200mL inulin extract,20℃under the elution 40min)â†'bleaching(D201-C macroporous resin,resin addition level 8.0g/200mL inulin extract,20℃under the elution 100min)â†'spray drying(inlet air temperature of 180℃,outlet temperature 80℃,flow 20mL/min)â†'pure inulin.Jerusalem artichoke inulin by the process of extraction rate to 98.31%,72.56% yield of inulin.(2)Gel properties of artichoke inulin.1)Under different extraction methods by the determination of the molecular weight of inulin known,impact of ultrasound on the molecular weight of inulin.By studying the different ultrasonic power on the molecular weight of inulin,we know that the introduction of ultrasound will damage the molecular structure of inulin,oligofructose facilitate its conversion to,and with the increase of ultrasonic power,conversion efficiency was increased.2)The system pH,metalion concentration,storage time and shear rate had effects on Inulin gel texture of the formation conditions and by inulin concentration.In the range of formation of the gel,to improve the inulin concentration,pH value,time and place the fried cut rates,be appropriate to reduce the gel formation temperature,which was an effective means to enhance the gel properties.High temperature and acidity,and promote the hydrolysis of inulin was not conducive to the improvement of gel properties.3)nulin gel with the apparent viscosity of the solution decreased with the increasing shear rate (shear thinning).Meanwhile,the phenomenon of shear thinning by the concentration,the higher the concentration of inulin can increase the viscosity of the solution system.Both system temperature and pH value increased may lead to lower viscosity,which was relevant to pectin molecule of activation energy and molecular structure of charged ion radical.Inulin solution system of divalent metal ions (copper,calcium) can play a significant addition of the thickening effect,the thickening effect was positively correlated with the ion concentration,but when the ion concentration in the gel concentration range,its thickening effect can be reduced to a minimum.Whether in high or low shear rate,shear stress of inulin gel solution was no relevant to time,polysaccharide molecules and water molecules,and interactions with polysaccharides molecular had a certain degree of stability and resistance to shear deformation ability.