Jerusalem artichoke residue as the research object,with the protein extraction rate as a measure indicator.Three extraction parameters including pH,extraction temperature and extraction time were optimized using central composite design and response surface methodology based on single factor investigations for achieving maximum the protein extraction rate.The interaction of the respective variables and their influence on the extraction rate were studied by using Box-Benhnken central composite design and response surface analysis theory,the simulated quadratic polynomial regression equation of prediction model was set up.Under the condition of solid-liquid ratio1：30（g/mL）,the optimum extraction condition for pH14,extraction temperature 82℃,extraction time of 2h.Under these conditions,the average protein yield ratio was 22.7747mg/g,compared to the theoretical value,the relative error of 2.33%.Optimized by response surface regression equation derived some practical significance.

采用日立835-50型高速氨基酸自动分析仪对鲜菊芋和从菊芋渣中提取蛋白的氨基酸含量进行了分析。结果表明:鲜菊芋中,总氨基酸含量约为1446.91mg/100g。菊芋渣蛋白中,总氨基酸含量百分比约为22.86%。采用碱提酸沉法从菊芋渣中提取蛋白质,对菊芋渣蛋白的功能特性进行了研究,并测定菊芋渣蛋白质等电点。结果显示,在其浓度3%、60℃、1.5h条件下持水性最好;蛋白质吸油性在80℃时最低,为5.10mL/g;其蛋白质分散指数(PDI)在60℃时最大,60℃以上PDI开始下降,70℃以后变化不大;菊芋渣蛋白质起泡性在浓度为3%时最高,泡沫稳定性在浓度为3%时最大;其乳化性在浓度为2%时最大,静置的温度对乳化稳定性影响很小;其等电点在4.00左右。

To optimize the extraction of monosaccharides from Jerusalem artichoke residue based on inulinase treatment,the single factor test and the orthogonal test were used.The results showed that the optimum conditions are pH4.6,enzyme dosage 25U/g,extraction temperature 60℃,liquid ratio 1∶ 25,the extraction time 6h.Under these conditions,the average extraction yield of monosaccharide is 82.67%.The hydrolysate contains mainly two kinds of simple sugars,fructose and glucose by TLC analysis.And the contents of two monosaccharides were 135.9mg/g and 84.9mg/g using the DNS method,the ratio of the two sugars was 1.6∶ 1.

The fusant strain called R8 which can secrete inulinase and produce alcohol was chosen to optimize the alcoholic fermentation in order to get high-yielding alcohol fermentation conditions. The optimum condition confmned through six single factor experiments and the orthogonal test was list as following： 160g/L JAE （Jerusalem artichoke extract）, 25g/L BE （beef extract）, 8g/L NH4H2PO4, 0.1 g/L ZnC12, pH6.0, 30°E, 180r/min. Finally, the yield of alcohol is 46.30% and the rate of raw material utilization is 84.96%.

The soluble protein of Jerusalem artichoke was extracted by the phosphate buffer. Single experiment and orthogonal experiment were used to discuss the optimized extraction,and the SDS-PAGE was used to analyze furthermore. The results showed that the optimal extraction conditions are as follows:ratio of material to solution 1:40(w/v),extraction time 4h,temperature 35℃,pH8.0. Under this condition,the average extracting rate of soluble protein was 14.7mg/g. In the SDS-PAGE,the molecular weights of these proteins were between 20.9 ku and 69.2 ku.