Study On Production Of High Fructose Syrup From Jerusalem Artichoke

In this paper, Jerusalem artichoke was as raw materials. The main ingredients of different kinds of Jerusalem artichokes were analyzed. The most important aim was to compare the difference between inulin content, and choosed the red skin Jerusalem artichoke as experimental materials with the highest inulin content. Inulin was extracted from Jerusalem artichokes by hot water extraction to get the crude inulin liquid. The effect of various factors on extraction of inulin has been studied through single factor and orthogonal experiments. The results showed the optimum conditions:solid to liquid ratio1:20, extraction temperature90℃, extraction time30min, and extracted twice. Milk of lime was added in crude inulin extraction solution to remove the protein and other impurities. The suitable conditions of deproteinization were as follows:pH11, heating for50min at80℃.The inulin solution was hydrolyzed through acid hydrolysis and enzymolysis. Phosphate acid was used to hydrolyze the inulin solution. Through single factor and orthogonal experiments, the effect of various factors on acid hydrolysis has been studied to get the optimum conditions:hydrolysis temperature90℃, time70min, pH1.5. The inulin solution was also hydrolyzed by Novozymes inulinase. Effect of pH of inulin liquid hydrolyzing temperature, volume of the inulinase and substrate concentration were investigated, and the most appropriate conditions were:pH=5, hydrolyzing temperature50℃, volume of enzyme0.39U/g inulin～0.52U/g inulin, substrate concentration15%. Under these conditions, hydrolysis rate was as high as95%.Fructose syrup obtained after hydrolysis needed to be decolorized by activated carbon or resin. Comparing the decolorization rate and sugar loss rate, the the optimum conditions of decolorization by activated carbon were fixed as:activated carbon add content9%. decoloring time20min at80℃.The decoloring results of6different kinds of resins were compared, and S-8was selected finally. Then the fructose syrup flowed through the cation resin column001×7and anion resin column S-8to remove cations and anions, including some organic impurities, ash and colored substances, and so on.The001×7strong acid cation resin was exchanged into calcium charged crosslinked polystryrene ion ecchage resin and then filled in a column with a jacket, which was used to separate the fructose and glucose, sucrose. The best technological conditions were: separation temperature70℃, the syrup concentration15%, the quantity of syrup0.025BV, the flow velocity0.375BV/h. The effluent with high fructose was collected and combined concentration to get high-fructose syrup and the concentration of fructose is90.5%. The final yield was50%(fructose and glucose quality/quality of Jerusalem artichoke powder). The main indicators of high-fructose syrup were detected according to relevant national standards, such as pH, solube solids content, etc. Results met the standard requirements.