【作者】 杨文；

【导师】 郑志；

【作者基本信息】 合肥工业大学 ， 粮食、油脂及植物蛋白工程， 2017， 硕士

【摘要】 小麦蛋白的蛋白质含量高,氨基酸组成全面,营养价值高。由于小麦蛋白本身含有较多的疏水性氨基酸,导致其溶解性、分散性等性能差,限制了其在食品加工中的应用范围。蛋白质组织化加工是通过加热、加压、成型、冷却等机械或化学方法改变蛋白质的组织结构,使蛋白质分子间形成有序的组织结构,在原料内部膨化和外部环境影响下凝固,形成纤维状结构蛋白。制备组织化蛋白主要采用螺杆挤压法实现,与传统的生产工艺相比,具有设备占地面积小、能耗低、生产效率高、操作简单等优点。本文以小麦蛋白为主要原料,研究了 8种添加剂对小麦蛋白挤压组织化过程中理化、质构、化学键及功能特性的影响,并开发组织化小麦蛋白休闲食品。研究主要结论如下:(1)通过响应面和多元回归分析,研究了挤压组织化过程中加水量、挤压温度、螺杆转速和喂料量4个工艺参数对组织化小麦蛋白组织化度和咀嚼度的影响,优化出挤压工艺参数为:加水量为32%,挤压温度为140℃,螺杆转速为410 r/min,喂料量为330 kg/h。在最佳工艺条件下制备的组织化小麦蛋白硬度为3008.91g,粘着力为-2.21 g.sec,弹性为0.72,咀嚼度为2292.29,恢复力为0.23,复水率为329.31%,组织化度为1.75。(2)研究了氯化钠、碳酸氢钠、三聚磷酸钠、L-半胱氨酸、L-抗坏血酸、柠檬酸钠、海藻酸钠和硬脂酰乳酸钙对组织化小麦蛋白的影响。结果表明:硬酯酰乳酸钠能够显著(P<0.05)提高组织化小麦蛋白的硬度和粘着力,当添加量为0.04%、0.08%时,粘着力和硬度分别达到最大的-13.87 g.sec和7869.97g;氯化钠能够显著降低挤压产品的粘着性,同时显著(P<0.05)提高弹性、咀嚼度和恢复性;当碳酸氢钠的添加量为0.5%时,组织化小麦蛋白弹性为1.05;添加了抗坏血酸和海藻酸钠后挤压产品的组织化度显著减小(P<0.05)。同时,发现当氯化钠、碳酸氢钠和海藻酸钠添加量为0.6%、0.4%和0.04%时,组织化小麦蛋白的复水率分别减小到234.33%、208.05%和209.46%。碳酸氢钠、三聚磷酸钠、海藻酸钠和硬脂酰乳酸钙在挤压过程中能够显著(P<0.05)影响小麦蛋白的疏水作用力;L-半胱氨酸和L-抗坏血酸的添加量越大,组织化过程中氢键作用越显著(P<0.05);当氯化钠和柠檬酸钠添加量为0.2%和0.5%时,组织化小麦蛋白的离子键作用力分别增加了117.35%和142.32%。红外光谱显示,氯化钠、三聚磷酸钠、海藻酸钠和硬脂酰乳酸钙能够促进小麦蛋白组织化,L-半胱氨酸对组织化小麦蛋白挤压效果有抑制作用。拉曼光谱显示,L-半胱氨酸能够显著(P<0.05)提高二硫键的含量,在添加了氯化钠和L-抗坏血酸后,组织化小麦蛋白的二硫键降低。还原SDS-PAGE电泳结果显示,在添加了 8种添加剂后,并没有发生亚基的裂解。扫描电镜结果显示,添加碳酸氢钠后,挤压产品出现很多小孔,结构比较疏松;三聚磷酸钠和柠檬酸钠使组织化产品微观结构中出现片状结构;海藻酸钠和硬脂酰乳酸钙使得挤压产品的纤维状组织结构变得更加紧密,气腔数量减少、大小变小。(3)添加了复配添加剂后,挤压产品的硬度和粘着性显著(P<0.05)提升;柠檬酸钠、硬脂酰乳酸钙、海藻酸钠的复配和柠檬酸钠、氯化钠、碳酸氢钠、L-半胱氨酸的复配显著提升组织化小麦蛋白组织化度33.50%和38.38%。复配添加剂对组织化蛋白离子键、氢键和疏水作用力的影响都明显小于单一添加剂。拉曼光谱显示,氯化钠、硬脂酰乳酸钙的复配和氯化钠、海藻酸钠的复配能够显著(P<0.05)提高二硫键的含量。扫描电镜结果显示,在挤压过程中添加了复配添加剂后,组织化小麦蛋白普遍微观结构更加紧密,表面光滑,气孔小且较少。(4)利用小麦蛋白经过挤压组织化后油炸,再用卤料开发具有肉纤维嚼劲的卤制休闲蛋白食品。具体工艺为:加入原料约2倍的水,放入卤料混合沸水煮20 min,熬制出卤料的香味,然后放入油炸好的组织化小麦蛋白半成品,卤制10 min,最后10min用大火将汤汁收干。优化的休闲食品油炸条件为:油炸油温为160℃,油炸时间为60-70 s。卤料配方为:八角(4.19%)、茴香(2.09%)、桂皮(1.40%)、食用盐(2.79%)、水(17.46%)、辣椒(2.09%)、味精(0.14%)、主料(69.83%)。该产品色泽鲜亮、质地紧密、嚼劲良好、口感协调,在20℃温度下储藏期可达2个月。更多还原

【Abstract】 Wheat gluten shows the characteristics of high protein content,comprehensive amino acid composition and high nutritional value.But it shows poor solubility and dispersibility due to it contains rich hydrophobic amino acids,which limits its application in food processing.The technology of protein texturization could change the structure of the protein through heating,pressurizing,molding,cooling and other mechanical or chemical methods to prompt the formation of ordered structure between protein molecules.The protein form fibrous structural protein after solidified under internal extrusion and external environment influence.Compared with the traditional production process,the preparation of the textured protein is mainly by screw extrusion.It has the advantages of small footprint,low energy consumption,high production efficiency and simple operation.To investigate the effect of eight additives on the physicochemical,texture properties,chemical bond and other properties of texturized wheat gluten(TWG),wheat gluten was used as raw material.The main conclusions are as follows:(1)Single factor and response surface method experiment were used to study the influence of adding water,extrusion temperature,screw speed and feed amount on the rehydration ratio,texturized degree and chewiness of TWG.The optimal conditions of extrusion process were optimized as:water addition 32%,extrusion temperature 140℃,screw speed 410 r/min and feed speed 330 kg/h.Under this conditions,the coefficient of hardness was 3008.91 g,the coefficient of adhesiveness was-2.21 g.sec,the coefficient of springiness was 0.72,the coefficient of chewiness was 2292.29,the coefficient of resilience was 0.23,the rehydration ratio was 329.31%,and the texturized degree was 1.75.(2)The influence of Nacl,NaHCO3,sodium tripolyphosphate,L-cysteine,vitamin C,sodium citrate,sodium alginate and calcium stearyl lactylate on the TWG were researched in this paper.The results showed that the calcium stearyl lactylate could significantly improve the organization of TWG.When the adding amount was 0.04%and 0.08%,the adhesiveness and hardness significantly increased by 7869.97 g and-13.87 g.sec,respectively.Moreover,the addition of Nacl caused significant(P<0.05)decrease of adhesiveness and increase of springiness,chewiness and resilience of TWG.When the adding amount of sodium bicarbonate is 0.5%,the springiness of TWG is 1.05.Vitamin C and sodium alginate displayed a dramatical(P<0.05)effect on the texturized degree of TWG(P<0.05).When the adding amount of sodium chloride,sodium bicarbonate and sodium alginate was 0.6%,0.4%and 0.04%,the rehydration ratio of samples decreased to 234.33%,208.05%and 209.46%of TWG,respectively.NaHCO3,sodium tripolyphosphate,sodium alginate and sodium stearyl lactylate could significantly affect the hydrophobic interaction of wheat gluten during the extrusion process.With the addition of L-cysteine and L-ascorbic acid,the effect of hydrogen bonding was more significant during the process of texturization.When sodium chloride and sodium citrate were added at 0.2%and 0.5%,the ionic bonding force of TWG increased by 117.35%and 142.32%,respectively.Fourier transform-infrared spectroscopy(FT-IR)revealed that Nacl,sodium tripolyphosphate,sodium alginate and calcium stearyl lactylate could significantly improve the fibrous structure,but L-cysteine was inhibited.Raman spectra showed that L-cysteine can significantly(P<0.05)increase the content of disulfide bonds,but the content of disulfide bonds decreased after the addition of sodium chloride and L-ascorbic acid.The result of protein gel electrophoresis indicated that no subunits were found with additives.Scanning electron microscopy(SEM)showed that the sodium bicarbonate make the extrusion product display small holes and loose structure;In additon,sodium tripolyphosphate and sodium citrate make the products appear flake microstructure;sodium alginate and calcium stearoyl lactate makes fibrous group extrusion product structure becomes more closely,decrease the air cavity number and small size.(3)Additives caused significant effect of hardness,adhesiveness or resilience of TWG.It was also found that the combination of sodium citrate,calcium stearoyl lactylate and sodium alginate and the combination of sodium citrate,Nacl,NaHC03 and L-cysteine could significantly enhance the texturized degree of TWG by 33.50%and 38.38%,respectively.The effect of compound additives on the ionic bond,hydrogen bond and hydrophobic interaction of the TWG was significantly smaller than single additive.Raman spectroscopy showed that compound additives significantly encouraged the content of disulfide bond during extrusion treatment.Scanning electron microscopy(SEM)showed that compound additives could make the fibrous structure more smooth of TWG.(4)Texturized wheat gluten snack food is made of textured wheat gluten via the process of extrusion,frying and stew and chewy similar to meat fibers.The optimum parameters of process were as follows:frying temperature 160℃,frying time 60-70 seconds.The better stew formula were as follows:star anise(4.19%),aniseed(2.09%),cinnamon(1.40%),food grade salt(2.79%),water(17.46%),chilli(2.09%),monosodium glutamate(0.14%)and main ingredient(69.83%).Forecast results for shelf life:The storage period is 2 months at 20℃.The processing method for texturized wheat gluten snack food is that add about 2 times the raw material of water,into the stew condiment mixed with boiling water for 20 minutes,boiled out of the smell of stew material,and then into the fried TWG,stew 10 minutes,the last 10 minutes with the fire to dry.更多还原