【作者】 陈善峰；

【导师】 申德超；

【作者基本信息】 河北农业大学 ， 农业机械化工程， 2012， 博士

【摘要】 目前世界范围内,除德国外,啤酒企业多以大米、玉米或其淀粉或糖浆为辅料生产啤酒,大米和玉米等谷物需要经过蒸煮使其糊化,传统生产方法的工艺流程长、耗汽量大。挤压蒸煮技术使得淀粉在挤压机内完成糊化,具有传统工艺无法比拟的优点;但高温挤压蒸煮啤酒辅料也存在糖化醪的糖化困难,过滤性能差的缺点。低温(﹤70℃)挤压啤酒辅料的方式,很好的解决了这一难题,并取得了国家专利。本研究是在发明专利“挤压膨化啤酒辅料的加工方法、加工装置和糖化方法(专利号:ZL 00122033.0)”、“啤酒辅料挤压的加工方法、加工装置和糖化方法(专利号:ZL 200510045328.6)”和“挤压不加酶和加酶啤酒辅料的加工方法、装置和糖化方法(200810014639.X)”等三项发明专利的基础上,在科技部农业转化资金等多项科研课题的资助下开展起来的。本研究分别进行低温挤压添加耐高温α-淀粉酶和中温α-淀粉酶的大米挤出物作啤酒辅料的试验研究,得出最优的挤压-液化系统参数,并通过研究挤压机内部大米化学成分和酶活性变化和建立HPLC法快速检测挤压大米糖组分,进一步揭示低温加酶挤压技术提高淀粉转化率的内在机理。(1)研究了低温挤压添加耐高温α-淀粉酶大米作啤酒辅料的挤压-液化系统参数(挤压温度、螺杆转速、挤压加酶量、液化加酶量、料水比)对其麦汁各项考察指标的影响规律。通过SAS软件应用表面响应法等方法对各考察指标进行分析与优化处理,得到较优挤压-液化系统参数组合,经过验证试验及生产中试,试验结果表明,低温挤压添加耐高温α-淀粉酶大米作啤酒辅料在技术上是可行的,各项指标均优于对照试验。通过响应面法试验和验证实验,得到了较优挤压-液化系统参数:挤压温度52.82~ 59.75℃;螺杆转速169.88~187.00r/min;挤压加酶量0.97~1.12L/t;液化加酶量0.53~0.62L/t;料水比1:4.23~1:4.79。在以上优化条件下挤压添加耐高温α-淀粉酶大米,在燕京(无名)啤酒有限公司进行生产试验,结果显示挤压加耐高温α-淀粉酶大米糖化后麦汁的浸出物收得率要高于传统不挤压大米糖化后麦汁的浸出物收得率,范围在1.20~3.04%,成品啤酒各项指标符合GB-4927-2001。(2)首次研究了低温挤压添加中温α-淀粉酶大米作啤酒辅料的挤压-糖化系统参数(挤压加酶量、液化加酶量、螺杆转速、液化温度、挤压温度)对其麦汁的各项考察指标的影响规律。通过SAS软件对各考察指标的分析与优化处理,得到较优挤压-液化系统参数组合,经过验证试验表明,挤压添加中温α-淀粉酶大米作啤酒辅料在技术上是可行的,主要指标优于对照试验。通过响应面法试验和验证试验,得到了较优挤压-液化系统参数:挤压加酶量4.27~5.74L/t;液化加酶量2.82~2.94L/t;螺杆转速198.51~226.72r/min;液化温度75.70~80.39℃;挤压温度63.62~69.00℃。(3)研究了加酶与不加酶大米的淀粉在挤压机内从喂入至挤出的过程中沿螺杆轴向的降解规律,其相同之处在于:淀粉的糊化度逐渐增大,淀粉含量和脂肪含量逐渐降低,添加酶制剂的大米辅料中酶活性逐渐降低;不同之处在于:加酶大米辅料,其还原糖含量逐渐增加,未加酶大米辅料,还原糖含量逐渐降低;加酶大米辅料,其抗性淀粉含量降低,未加酶大米辅料,抗性淀粉含量增加。(4)首次应用HPLC对大米淀粉挤压过程(加酶或不加酶)中的糖组分进行检测,揭示加酶挤压和不加酶挤压的差异,并形成一种用于检测挤压大米中糖组分的HPLC方法。其色谱条件为:色谱柱:(Carbohydrate High Performance 4μm,尺寸:4.6mm×250mm Cartridge;美国Waters公司);流动相:81%乙腈+19%水超纯水,流速:1.1ml/min;检测器池温度:温度35℃;柱温:45℃;进样量:15μl。该方法测定速度快,结果准确。低温挤压未加酶大米挤出物的糖组分为:果糖0.002(g/ml),葡糖糖0.078(g/ml),蔗糖0.036(g/ml),麦芽糖0.383(g/ml),麦芽三糖0.004(g/ml)。低温挤压添加耐高温α-淀粉酶大米挤出物的糖组分为:果糖0.121(g/ml),葡糖糖1.216(g/ml),蔗糖0.093(g/ml),麦芽糖3.955(g/ml),麦芽三糖3.207(g/ml)。低温挤压添加中温α-淀粉酶大米挤出物的糖组分为:果糖0.129(g/ml),葡糖糖1.953(g/ml),蔗糖0.366(g/ml),麦芽糖2.942(g/ml),麦芽三糖2.331(g/ml)。以上试验研究为低温挤压加酶大米作啤酒辅料在啤酒生产中的应用提供了科学依据。更多还原

【Abstract】 At present around the world, except Germany, most of the beer enterprises used rice, corn starch and syrup as adjunct. The rice and corn need to be cooked and make them gelatinization. But the process of the traditional method is long and consumes a large amount of steam.Extrusion cooking technology could make starch gelatinize in the extruder, which has an significant advantages compared to the traditional process. But high temperature extruded adjunct also has the the difficulty in saccharification of the mash and the poor performance of filtration.The low temperature extruded beer adjunct (lower than 70℃) solved this problem and obtained national patent. The paper was carry out at the base of three patents < Processing method, equipment and saccharifaction method of extruded expansion beer adjunct, Patent No. 00122033.0;Processing method, equipment and saccharifaction method of extruded beer adjunct, Patent No. 200510045328.6; Processing method, equipment and saccharifaction method of extruded beer adjunct with or without enzymes, Patent No. 200810014639.X)> and the funds of the ministry of science and technology agricultural transformation. The study obtained the optimization parameters of extrusion-liquefaction after the experiments of extruding rice adding thermostableα-amylases and mesophilicα-amylases separately as beer adjunct. The change of the chemical composition of rice in extruder was studied and constructed a method to determined the sugar composition by HPLC.(1) It was studied the influence of liquefaction-extrusion system pararmeters (extrusion temperature, screw rotate speed, the content ofα-amylase during extrusion, the content ofα-amylase during liquefaction, ration of water to material) on the index of wort made from extruded rice added thermostableα-amylases as adjunct.The optimized pararmeters of liquefaction-extrusion system were got through analysising and optimizing the index by the regression method of SAS. The results show that extruded rice added thermostableα-amylases used as beer adjunct was feasible, and the index of validated results were advantage than those of contrast experiment through the validated tests.The optimized system pararmeters of liquefaction-extrusion by orthogonal tests and validated experiments were below: the extrusion temperature was 52.82~59.75℃, the screw rotate speed 169.88~187.00r/min, the content ofα-amylase during extrusion 0.97~1.12L/t, the content ofα-amylase during liquefaction 0.53~0.62L/t, the ration of water to material was 4.23~4.79.(2) It was studied the influence of extrusion- liquefaction system pararmeters (the content of amylase during extrusion, the content of amylase during liquefaction, screw rotate speed, liquefaction temperature, extrusion temperature) on the index of wort made from extruded rice added mesophilicα-amylase.The optimized pararmeters of extrusion- liquefaction system were got through analysising and optimizing the index by the regression method of SAS. The validated results showed that the process of producing wort used extruded riceadded mesophilicα-amylases as beer adjunct was feasible, and the index of validated results were advantage than those of contrast experiment.The optimized pararmeters of extrusion-liquefaction system by orthogonal tests and validated experiments were below: the content of amylase added to rice during extrusion was 4.27~5.74L/t, the content of amylase during liquefaction 2.82~2.94L/t, the screw rotate speed 198.51~226.72r/min, the liquefaction temperature was 75.70~80.39℃, the extrusion temperature 63.62~69.00℃.The rice was extruded under the optimizing parameters and took saccharfication- fermentation pilot scale production in beer enterprise. The results was shown that the the yield of beer increased 2~3% of extruded rice added enzymes as beer adjunct than that of extruded native rice. All the indexes of beer meeted the national standard(GB-4927-2001).(3) The change of main chemical compositions of rice and enzymes during was determined. The samples were took at the specified 6 points along the screw direction. The results showed that the enzyme activity was decreased, the gelatinization degree was increase, the content of starch and lipid was decreased. The difference of reducing sugar of extruded native rice added enzymes was increased obviously than that of the extruded native rice. The reducing sugar of extruded native rice was decreased. The resistant starch of extruded rice added enzymes was decreased, but that of the extruded native rice was increased.(4) The determined method of sugar components among extruded rice by HPLC was obtained. The chromatogram conditions was shown below: the chromatographic column (Carbohydrate High Performance 4μm,size:4.6mm×250mm Cartridge;American Waters Co., LTD) ;Waters Carbohydrate High Performance 4μm chromatographic column with refractive index detector; the mobile phase: elution influent acetonitrile: ultrapure water (V,V)81:19,flow rate 1.1ml/min;Detector pool temperature: 35℃; the column temperature: 45℃;the injection volume15μl. The measurement method was quick and accurate.The sugar components of extruded native rice was shown below: the content of fructose was 0.002(g/ml), the content of glucose was 0.078(g/ml), the sucrose was 036(g/ml),the maltose was 0.383(g/ml),the maltotriose was0.004(g/ml).The sugar components of extruded rice added thermostableα-amylases was shown below: the content of fructose was 0.121(g/ml), the content of glucose was 1.261(g/ml), the sucrose was 0.093(g/ml),the maltose was 3.955(g/ml),the maltotriose was3.207(g/ml).The sugar components of extruded rice added mesophilicα-amylases was shown below: the content of fructose was 0.129(g/ml), the content of glucose was 1.953(g/ml), the sucrose was 0.366(g/ml),the maltose was 2.942(g/ml),the maltotriose was2.311(g/ml).The experimental study on rice added with enzymes extruded at low temperature used as beer adjunct provide a scientific basis in beer production.更多还原