挤压膨化及添加粗酶对水相制取大豆油和蛋白质的影响

以全脂豆粉为研究对象,考察挤压膨化和添加粗酶对水相制油工艺中总油、总蛋白提取率及蛋白性质的影响。结果显示,全脂豆粉未经挤压膨化和无粗酶添加的水相提油工艺,总油和总蛋白得率较低,分别为60.31%和66.33%,采用挤压膨化豆粉而未添加粗酶水相制油工艺的总油提取率为65.12%,总蛋白提取率为55.1%;添加粗酶而豆粉未经挤压膨化的制油工艺总油和总蛋白提取率与无粗酶水相提取未膨化豆粉的总油和总蛋白得率相似;而挤压膨化联合粗酶添加却使水相制油工艺的总油、总蛋白提取率显著提升,分别达到94.25%和90.13%。由于酶水解造成蛋白在pH4.5附近溶解性增加,因此水相粗酶制油工艺采用等电点方式回收蛋白得率较低。相比于无酶添加的水相制油工艺,挤压膨化联合粗酶提油工艺所得蛋白的溶解性、持水性更好,而黏度、疏水性、吸油性、乳化性和乳化稳定性、起泡性和泡沫稳定性等性能均有所下降。     

挤压膨化预处理技术对灵芝多糖提取的影响

以灵芝子实体为原料,在热水浸提前进行双螺杆挤压膨化预处理,以提高灵芝多糖的提取得率。分别采用单因素和正交实验对物料提取前的挤压膨化预处理条件进行优化,然后采用高效凝胶排阻色谱对比了挤压膨化预处理对水提灵芝多糖分子量分布的影响。在物料粒度60目时,通过优化得到了双螺杆挤压膨化预处理的最优工艺:套筒温度160℃,固液比1:3,螺杆转速150 r/min,采用上述条件进行预处理后,灵芝多糖的提取得率为7.92%,较未挤压膨化灵芝的多糖提取得率提高了92.7%,表明采用双螺杆挤压膨化技术对灵芝子实体进行预处理,可显著提高灵芝多糖的提取得率,同时双螺杆挤压膨化预处理会增加灵芝多糖提取物中低分子量多糖的比例。     

发酵全脂大豆粉提取油和蛋白的研究

采用发酵工艺分别联合磨碎和挤压膨化前处理技术制取大豆油和蛋白,通过油和蛋白得率及其品质评估工艺的可行性。结果显示发酵全脂豆粉联合挤压膨化能够显著提高油和蛋白提取率,总油和总蛋白得率分别为95.1%和87.12%,与水酶法得率相近,显著高于磨碎前处理工艺。磨碎豆粉与膨化豆粉经发酵提取油的品质和脂肪酸组成相似,均优于溶剂浸提油;磨碎与膨化豆粉发酵所得分离蛋白(FE-SPI和FGSPI)分子质量主要分布在10 000 u以下,FE-SPI的功能性优于或接近于FG-SPI,二者的溶解性、持水性显著优于碱溶酸沉制取的分离蛋白(W-SPI),但疏水性、持油性、乳化性、发泡性能及黏度均低于W-SPI。研究证实发酵联合挤压膨化提取大豆油作为一项环境友好制油技术具有良好的应用前景。     

酶法水解大豆膨化料提取多肽的工艺

采用挤压膨化预处理水酶法提取大豆油的同时,也有较高的多肽得率。利用水酶法应用于大豆多肽的提取,并应用响应面优化方法得出大豆挤压膨化后水酶法提取多肽的最佳工艺为加酶量1.6%、酶解温度60℃、酶解时间3h、料水比1:5、酶解pH9.6。经过验证与对比实验可知,在最优酶解工艺条件下大豆多肽得率可达到41.36%左右,比相同酶解条件下未经挤压膨化预处理大豆多肽得率有显著提高。     

真空挤压膨化预处理水酶法提取大豆蛋白工艺研究

以大豆为原料,对真空挤压膨化预处理水酶法提取大豆蛋白工艺进行研究。在单因素试验基础上,通过响应面分析法对真空挤压膨化预处理工艺进行优化,确定最优工艺条件为:真空度-0.057 MPa,物料含水率15%,套筒温度94℃,螺杆转速98 r/min,模孔孔径17 mm。在最优工艺条件下总蛋白提取率高达92.17%,比传统湿热预处理工艺提高了近14个百分点;同时,提油效果显著,总油提取率高达93.61%。     

不同提取方法对茶渣蛋白功能特性的影响

以单枞茶叶为实验材料,研究了单一碱法提取、挤压膨化预处理碱法提取、挤压膨化预处理酶法提取对茶渣蛋白功能特性的影响。结果表明,与单一碱法提取的茶渣蛋白相比较,挤压膨化预处理碱法提取的茶渣蛋白吸水性、持水力、起泡性和乳化性分别提高了25%、43.43%、8.79%、5.57%,吸油性降低了8.67%;挤压膨化预处理酶法提取茶渣蛋白吸水性、持水力、起泡性和乳化性分别提高了34.73%、86.87%、18.01%、12.46%,吸油性降低了18.50%;挤压膨化预处理对茶渣蛋白功能特性有一定的改善作用。     

挤压膨化对大豆磷脂的影响

简述挤压膨化技术及其在油脂生产中的应用，挤压膨化对制取大豆磷脂的影响。采用挤压膨化预处理工艺制取油脂可以提高毛油的脱胶效率，改善油的品质，增加磷脂的得率，增强磷脂的性能。     

大豆水酶法提取副产物-水溶性糖工艺优化及机理研究

水酶法提油条件温和,油料蛋白的性能几乎不发生变化,无论是水相中直接加工利用,还是回收分离蛋白再利用,效果都十分理想,但有关水酶法提取植物油脂和蛋白质的副产物-水溶性糖的相关研究较少,故针对挤压膨化后水酶法提取大豆油脂和蛋白质的副产物-大豆水溶性糖进行研究。利用响应面分析方法对酶法提取副产物-大豆水溶性糖得率进行了优化。建立了相应的数学模型,为以后的中试以及工业化生产提供理论基础,并且得到了最优酶解工艺条件为加酶量为2.1%,温度为58℃,酶解时间为3.5 h,料水比为1:6.4,pH为10,响应面有最优值在(20.98±1.03)%。经过验证与对比试验可知在最优酶解工艺条件下水溶性糖得率可达到19.97%左右,比相同酶解条件下未经挤压膨化预处理水溶性糖得率以及碱提工艺水溶性糖得率均有显著提高。利用超微结构能谱分析为手段,针对水溶性糖得率提高机理进行了研究,经研究表明:①挤压膨化再粉碎后大豆细胞组织破坏,水溶性糖与蛋白复合物中蛋白质与蛋白酶作用位点较充分暴露,有利于其酶解使得水溶性糖与蛋白复合物破坏。②大豆中水溶性糖部分以糖与蛋白复合物形式存在,而想提取此类大豆水溶性糖需要将蛋白水解。     

酶法水解膨化玉米蛋白的生产技术研究

采取不同的膨化预处理方法,摸索提高玉米蛋白水解度的途径.试验结果表明采用挤压膨化预处理后,玉米蛋白(含水量为12%)氮溶指数达51.7%,极大改善了玉米蛋白的水溶性功能.膨化玉米蛋白粉碎至80目,底物固液比为1∶12,利用碱性蛋白酶Alcalase水解3 h,水解度可达33.7%.蛋白水解液利用活性炭二次吸附后,色泽明显变浅、苦味变淡.     

猴头菇多糖挤压膨化预处理提取工艺优化

采用挤压膨化技术与植物化学物现代提取分离技术相结合,根据药食同源药味的作用特点,将猴头菇经双螺杆挤压机挤压膨化后采用水提醇沉法进行多糖提取,而后选择蒽酮硫酸法测定多糖含量。首先采用单因素试验考察螺杆转速、水分含量、挤压温度3个因素对猴头菇中多糖提取率的影响,筛选出最佳水平后,以多糖提取率为响应值,采用响应面分析法进一步优化,从而确定其多糖提取的最佳挤压膨化参数。最终优化结果为:螺杆转速400 r/min,水分含量16%,挤压温度120℃。在最优工艺验证试验下多糖得率可达3.63%,与预测值非常接近,说明响应面法建立的模型预测性良好,能够合理地优化挤压膨化预处理提取工艺。     

挤压膨化预处理水酶法提取大豆蛋白的工艺研究

采用水酶法结合挤压膨化预处理提取大豆蛋白,筛选5 种蛋白酶,确定选用碱性蛋白酶作为水解酶;得出碱性蛋白酶提取大豆蛋白的最佳条件：加酶量1.9%、酶解温度50℃、酶解时间200min、料水比1:4.6、酶解pH8.5,经过验证与对比实验可知在最优酶解工艺条件下总蛋白提取率可达到93.76%左右,比传统的湿热预处理后酶解的总蛋白提取率78.83% 提高了近15 个百分点。     

双螺杆挤压对大豆蛋白体外消化率的影响

采用双螺杆挤压技术,研究了挤压工艺参数对大豆蛋白体外消化率的影响,并采用二次通用旋转组合设计,建立了大豆蛋白体外消化率与物料含水量、挤压温度、喂料速度、螺杆转速的二次回归方程,并利用该方程探讨了各因子对消化率的影响.结果表明,各因子对大豆蛋白体外消化率的影响顺序为:挤压温度>物料含水量>螺杆转速>喂料速度,物料含水量与挤压温度交互作用显著.利用统计优选法寻优,确定了大豆蛋白消化率的最佳挤压工艺条件:物料含水量35%,挤压温度155℃,喂料速度0.4 kg·min-1,螺杆转速150r·min-1,大豆蛋白体外消化率最高值为95.83%.     

Dynamic mechanical properties and fractal analysis of texturized soybean protein/wheat gluten composite produced by high moisture extrusion

Texturized soybean protein (TSP) and wheat gluten were prepared at high moisture using a twin-screw extruder. Effects of feed moisture content, extrusion temperature and wheat gluten content on the dynamic mechanical properties, microstructures and fractal analysis of texturized soybean protein/wheat gluten composite were investigated. All extruded samples were well fitted with Burger's model in creep-recovery tests (R² ≥ 0.978). The creep-recovery rate decreased with an increasing extrusion temperature. The addition of wheat gluten increased the resistance to creep and the unrecoverable deformation of TSP samples. The extrusion parameters affected the microstructure and morphology of extruded products. The fractal dimension of TSP products decreased with an increase in moisture content and wheat gluten content. Texturized soybean protein (TSP) and wheat gluten composite could form well-structure products.     

大豆蛋白挤压组织化力学特征和感官评价

以大豆蛋白为原料,开发一种即食性的大豆蛋白组织化挤压产品。采用正交试验设计,通过感官评价得到最适的挤压参数为水分含量15%,转速120r/min,挤压温度160℃,在此条件下得到的挤压产品硬度4.0N,脆度22.1mm,膨胀率329%。扫描电镜观察结果显示产品具有均匀结构,此外,利用扫描量热仪示差测量该产品,产品具有良好的热稳定性。     

酶法制备豆皮低聚木糖的工艺研究

利用木聚糖酶酶解豆皮制备低聚木糖,通过单因素试验考察酶解温度、pH 值、时间、料液比以及酶添加量对酶解液中低聚木糖含量的影响,并在此基础上通过正交试验确立最佳酶解工艺条件：酶添加量0.3%、pH4.3、料液比1:15(g/mL)、温度40℃、酶解时间2h。该最佳工艺条件下,总还原还原糖含量为5.74mg/mL。通过离子色谱检测酶解液中的糖分组成,发现酶解液中的单糖以木糖为主,相对含量达到54.99%。     

水酶法制取大豆油的水解度对提油率影响机理研究

以挤压膨化预处理后的全脂大豆粉为原料,在单因素试验的研究基础上,以加酶量、酶解温度、酶解时间、料水比和酶解pH五个因素为自变量,以总油提取率与水解度为响应值,得到适宜的酶解条件为:加酶量1.8%、温度52℃、酶解时间3.75h、料水比1:6.5、pH9.4,经过验证与对比试验可知,在优化的酶解工艺条件下总油提取率可达到91.67%,对应的水解度为26.37%。对2个考察指标的降维分析图进行对比分析,探讨了水解状态与脂肪分子释放情况以及脂蛋白分解情况的关系,为水酶法生产大豆油提供理论基础。     

Effect of Pre-Treatments on Mechanical Oil Expression of Soybean Using a Commercial Oil Expeller

The effect of expeller screw press and pre-treatments on the quality and quantity of soybean oil and cake was studied using a commercial oil expeller. The pretreatments included whole soybean crushing, soy grits crushing, and crushing of soy grits extruded at 135°C. The screw speeds were 28, 35, and 45 rpm. The moisture content of soybean used in the experiment was 10% wet basis. The average capacity of the oil expeller was found to be 145 kg/h, 110 kg/h, and 120 kg/h for whole, grits, and extrudate, respectively at 45 rpm. The average capacity of oil expression from whole soybean did not vary significantly from 28 to 45 rpm. In the case of soy grits, however, the capacity was higher when the expeller speed was lowest, i.e., 28 rpm. In the case of extrudate, even in a single pass, the recovery was higher, i.e., to 71% at both 45 and 35 rpm. The color of oil from soy grits was lighter followed by extrudate, and the color of oil obtained from whole soybean was dark. The FFA in oil from all the samples was below 1%, however the lowest percentage was for oil obtained from extrudate at 0.5%. The urease activity of the extruded cake was 0.15 pH units, and the protein and oil content were about 48% and 5%, respectively. The optimum process variables for mechanical expelling of soybean were found to be extrusion as a pretreatment and speed of expeller screw at 45 rpm, which yielded throughput capacity 103 kg/h, oil recovery of 70.5%, and urease activity of the cake at 0.15.     

AQUEOUS EXTRACTION OF OIL AND PROTEIN FROM SOYBEAN AND LUPIN: A COMPARATIVE STUDY

This study compares the effects of extrusion pretreatment and protease addition during aqueous extraction processing (AEP) of soybean and lupin flakes. AEP of flakes resulted in the lowest yields of oil (56%), protein (71%) and [cream  +  free oil] (8%) for soybean, while for lupin, yields were 48, 69 and 2%, respectively. AEP protein extraction yields were decreased by extrusion pretreatment, but this pretreatment improved enzymatic action, increasing protein extractability from soybean and lupin by 47 and 26%, respectively. For both protein crops, enzyme-assisted AEP (EAEP) of extruded flakes yielded the highest oil, protein and [cream  +  free oil] yields, which were 96, 85 21%, respectively, for soybean. Yields for lupin were 81, 77 and 10%, respectively. Extrusion followed by enzyme addition positively impacted demulsification yield, the creams from EAEP of soybean and lupin extruded flakes being the less stable toward enzymatic demulsification .

PRACTICAL APPLICATIONS

The vegetable oil industry is looking for alternatives to the traditional solvent extraction of oil-bearing seeds, and there is a need to increase the inefficient conventional aqueous extraction of protein from residual defatted meal, a by-product of the oil extraction process. The concept of enzyme-assisted aqueous extraction processing (EAEP) has been successfully developed for extruded soybean material, but its efficiency on other oil-bearing seeds still needs to be demonstrated. By determining the oil and protein extraction yields recovered during EAEP of extruded lupin flakes, the feasibility of transferring this process from soybean to other oilseeds will be established.     

大豆蛋白挤压组织化加工影响因素及应用

大豆是我国重要的植物蛋白资源,而经过低温压榨取油后的豆粕是生产植物蛋白的重要原料。本文对大豆蛋白挤压组织化原理及特性、组织蛋白拉丝蛋白加工方法以及组织蛋白的种类应用进行了介绍,其中详细介绍了挤压膨化法加工组织蛋白的工艺流程及生产过程中原料、设备、工艺参数等对组织蛋白结构、弹性、吸水性的影响,最后对未来组织蛋白在仿真肉上应用的进行了展望。     

Low temperature dry extrusion and high-pressure processing prior to enzyme-assisted aqueous extraction of full fat soybean flakes

Oil, protein and solid extraction yields obtained during aqueous extraction processing (AEP) of full fat soybean flakes (FFSF), FFSF extruded at a die temperature of 100 °C and FFSF pressurised at 200 and 500 MPa for 15 min at 25 °C, were compared to those obtained during enzyme-assisted aqueous extraction processing (EAEP) using 0.5% of protease Protex 7L. Without enzyme addition, pretreatment of the FFSF with extrusion and 500 MPa increased and decreased, respectively, the oil extraction yield while protein extraction yield was significantly decreased after both treatments. The best treatment in terms of oil and protein recovery was EAEP of extruded flakes with 90% and 82% of oil and protein extraction yield, respectively, and 17% of free oil. Addition of protease during extraction significantly decreased the yield of isolated soy protein (ISP) due to an increased solubility of the proteins at pH 4.5. ISP from extruded EAEP had higher solubility at pH 7.0 and better functionality. The DSC results, combined with the protein extraction yields, showed that a proportion of the proteins became insoluble after extrusion and 500 MPa treatment, while only those extracted from 500 MPa FFSF had a reduced native state.