Reduction of Flatulence-Causing Sugars by High Temperature Extrusion of Pinto Bean High Starch Fractions

Pinto bean high starch fractions were extruded using a Wenger TX-52 twin screw extruder. The effect of process temperature and moisture in the barrel on flatulence-causing sugars was investigated. Levels of flatulence causing sugar were lower in extruded compared to non-extruded samples with higher reduction at higher process temperature. Sugar content decreased from 5.29% in nonextruded samples to 3.69% in samples extruded at 163°C. Moisture content in the extruder barrel did not significantly affect sugars in the samples. Raffinose and stachyose contents were reduced 47 to 60% by extrusion.     

Enzyme—Pretreatment of Pinto Bean High Protein Fraction and Time of Blending Corn Meal Affects Extrudate Properties

High protein fraction of pinto bean, treated with papain and cellulose enzymes (Solvay Enzymes Inc.), was blended with corn meal (30%) and extruded at 120°C. Changes in expansion, texture, color, pH, in vitro protein digestibility, reducing sugars and functional properties of extmdates were recorded. Changes depended on type of enzymes and time of corn incorporation (before or after enzymatic pretreatment). The best texture of the extrudates was obtained using a cellulase enzyme. Papain affected some functional properties such as NSI and WSI. The best improvement in in vitro protein digestibility and reducing sugars was found with a cellulase treatment. Protein and fiber could be modified to improve physicochemical and functional properties of extrudates.     

木瓜蛋白酶水解海洋鱼鳞蛋白的工艺研究

研究了木瓜蛋白酶水解鱼鳞蛋白的单一影响因素,并采用L9(34)正交实验,考察了温度、时间、酶量、底物浓度等因素对水解鱼鳞蛋白的影响.确定了木瓜蛋白酶水解鱼鳞蛋白工艺条件,即温度65℃,时间75 min,酶量0.04 g/g鱼鳞,底物浓度10％,适合规模化生产.     

木瓜蛋白酶对菠菜叶蛋白的改性研究

利用木瓜蛋白酶对菠菜叶蛋白进行酶法改性,通过均匀试验得出,酶解菠菜叶蛋白的最佳条件为温度55℃,pH6.5,E/S为0.5%,时间为2 h,菠菜叶蛋白的水解度可达15.85%;通过比较在不同pH下酶解前后菠菜叶蛋白的部分功能性质,结果表明,酶解后菠菜叶蛋白的等电点由原来的4.0漂移至3.4,且其溶解性、起泡性、稳定性及其乳化性较改性前均有不同程度的提高。     

高水分挤压纤维化蛋白不同储藏方式对品质特性的影响

本研究以大豆分离蛋白、小麦蛋白、豌豆蛋白为原料,采用高水分植物蛋白双螺杆挤压纤维化技术制备蛋白样品,并探讨不同储藏方式对其品质特性的影响。通过对四种不同储藏方式的安全指标进行检测,未杀菌-18℃储藏和121℃杀菌后24℃储藏条件下,其储藏时间较长,在检测的180天内,各项安全指标均在安全范围内。对上述两种储藏方式下随着储藏时间的增加,其品质特性的变化规律进行研究,结果表明：不同储藏方式对高水分挤压纤维化蛋白品质特性的影响显著。未杀菌-18℃储藏条件下,可以很好的维持样品的组织化度,同时样品的水分在储藏过程中从内部向外部发生迁移,随着样品水分不断减少,亮度下降,颜色变深,硬度和咀嚼度升高,弹性下降;121℃杀菌24℃储藏条件下,样品受到高温高压作用,蛋白变性,纤维状结构被破坏,其组织化度下降,样品发生美拉德反应,颜色加深,硬度和咀嚼度升高,弹性下降。对高水分挤压纤维化蛋白产品各品质指标之间进行相关性分析。组织化度与L*值、b*值和弹性呈现显著正相关,与a*值、硬度和咀嚼度呈现显著负相关;L*值与弹性呈显著正相关,与a*值、硬度和咀嚼度呈现显著负相关;a*值与硬度和咀嚼度呈现显著正相关,与弹性呈现负相关;b*值与弹性呈现负相关,与硬度呈现正相关;硬度与咀嚼度呈现正相关,与弹性呈现负相关;弹性与咀嚼度呈现负相关。     

木瓜蛋白酶水解黄粉虫蛋白质工艺条件的优化

目的优化木瓜蛋白酶水解黄粉虫蛋白质的工艺。方法以黄粉虫为原料,研究了酶用量、固液比、水解时间、水解温度及p H对氨基酸提取率的影响。结果最佳酶解条件为：酶用量2.5%,固液比1∶3,水解时间6 h,水解温度50℃,pH值6.75。结论得到了用木瓜蛋白酶水解黄粉虫蛋白质的最佳酶解工艺。     

木瓜蛋白酶水解黄粉虫蛋白质工艺条件的优化

目的优化木瓜蛋白酶水解黄粉虫蛋白质的工艺。方法以黄粉虫为原料,研究了酶用量、固液比、水解时间、水解温度及p H对氨基酸提取率的影响。结果最佳酶解条件为:酶用量2.5%,固液比1∶3,水解时间6 h,水解温度50℃,pH值6.75。结论得到了用木瓜蛋白酶水解黄粉虫蛋白质的最佳酶解工艺。     

木瓜蛋白酶中主要组分凝固大豆蛋白的特性

采用SP-Sepharose Fast Flow阳离子交换柱分离木瓜蛋白酶得到木瓜凝乳酶和木瓜蛋白酶，测定了两种酶在不同条件下凝固大豆蛋白质过程中体系粘弹性质的变化曲线和水解进程曲线．结果表明20℃下体系形成的凝胶比40℃下形成的稳定，而且体系在低温下形成凝胶所用的酶活力比高温下所用的低；木瓜凝乳酶-SPI体系比木瓜蛋白酶-SPI体系形成凝胶所需酶活力低，且最终形成凝胶强度高，说明木瓜凝乳酶促凝SPI效果比木瓜蛋白酶好．两种酶凝固大豆蛋白的机理和作用方式存在区别．     

木瓜蛋白酶水解大豆浓缩蛋白及糖基化修饰对水解产物溶解性的影响

为提高大豆浓缩蛋白(soy protein concentrate,SPC)在等电点处的溶解性,采用木瓜蛋白酶对大豆浓缩蛋白进行酶解,形成可溶性大豆蛋白,然后将其与葡聚糖进行糖基化反应,形成亲水的蛋白质-多糖复合物。结果表明:大豆浓缩蛋白酶解最佳条件为大豆蛋白与水质量配比5:100、酶添加量10000U/g、反应温度55～60℃;糖基化最佳条件为葡聚糖与蛋白配比1:1、反应时间3.5h;大豆浓缩蛋白在等电点附近(pH4)的氮溶指数由原来的9.53%提高到39.12%。本实验制备的等电点可溶大豆蛋白,可增加其在中等酸度食品中的应用。     

Physicochemical Properties of Field Pea, Pinto and Navy Bean Starches

Legume starches were compared for physicochemical properties that may explain differences in functional properties. Field pea starch had higher amylose, greater swelling power and solubility, and lower pasting temperatures than pinto and navy bean starches. Scanning electron microscopy (SEM) showed that field pea starch had larger, more irregularly shaped granules and more broken large granules than pinto or navy starches. The most starch damage was observed for field pea. Pinto and navy bean starches had greater resistance to swelling at 60°C than field pea indicating a more strongly bonded micellar network. Higher cold paste viscosity was observed for navy bean and field pea.     

Protein-Protein Interactions in the Extrusion of Soya at Various Temperatures and Moisture Contents

Soya protein isolate extruded at various temperatures and moisture contents was solubilized before and after processing in buffers containing urea, sodium disulphite, 2-mercaptoethanol, sodium dodecyl sulphate, alone or in combination to elucidate stabilizing mechanisms for their three dimensional structure. The main mechanisms were disulphide linkages, hydrophobic and electrostatic interactions. All extrudates resisted retorting in water at 120°C but complete disruption occurred in media containing reducing agents plus sodium dodecyl sulphate. Little change in amino acid occurred in extrusion except for aspartic and glutamic acids, which decreased in extrusion at 140°C. Infrared spectra showed the presence of β-sheet anti parallel structures. Peptide bonds were of negligible importance in extrusion texturization of soya protein. If formed they only contributed to an insoluble phase in the melt.     

挤压工艺参数对高水分组织化小麦蛋白产品特性的影响

研究含水量、螺杆转速、喂料速度、挤压温度等挤压工艺参数对高水分组织化小麦蛋白产品特性的影响。以小麦蛋白为主要原料,采用高扭矩双螺杆挤压装备开发高水分组织化小麦蛋白,并分析了产品色泽品质(L~*、a~*、b~*、ΔE)、质构特性(组织化度、硬度、黏着性、弹性、聚结性、咀嚼度)、感官评价。结果表明:随着含水量的升高,组织化蛋白产品色泽品质呈上升趋势,质构特性(组织化度先下降后升高)呈下降趋势;随着螺杆转速的升高,组织化蛋白产品色泽品质呈先升高后下降趋势,质构特性呈先下降后升高趋势;随着喂料速度的升高,组织化蛋白产品色泽品质、质构特性(组织化度先下降后略有升高)呈上升趋势;随着挤压温度的升高,组织化蛋白产品色泽品质、质构特性呈先升高后下降趋势。综合考虑组织化蛋白产品色泽品质、质构特性和感官评价,较适宜的挤压工艺为含水量49%,螺杆转速330 r/min,喂料速度10~11 kg/h,挤压温度170℃。     

大豆蛋白的挤压组织化及其应用

蛋白源紧缺一直是人类发展面临的问题,我国大豆资源丰富,如何利用好大豆,开发附加值高的大豆蛋白产品具有重要意义。综述了挤压组织化大豆蛋白的生产原理、工艺流程、特点以及挤压过程中蛋白质的作用及性质变化,并介绍了组织化大豆蛋白的应用。     

Functional and Nutritional Properties of Extruded Whole Pinto Bean Meal (Phaseolus Vulgaris L.)

Pinto bean meals with 18, 20, and 22% moisture were extruded at 140,160 and 180°C, using screw speeds of 150,200 and 250 rpm in a single-screw laboratory extruded. Expansion index, bulk density, water absorption and solubility indices, in vitro protein digestibility, and trypsin inhibitor activity in extrudate were measured. Temperature and feed moisture influenced (p<0.05) expansion index, bulk density, water absorption index and in vitro protein digestibility. Water solubility index was affected by temperature only. Trypsin inhibitors were inactivated completely for all conditions. Screw speed had no effect on any dependent variable. Best product was produced with 22% feed moisture at 160°C.     

木瓜蛋白酶作用于林蛙油蛋白质水解功能特性的研究

本研究以林蛙油为底物,加酶水解,实验确定林蛙油水解最适宜的酶制剂为木瓜蛋白酶。与林蛙油相比,水解产物具有很好的溶解性,游离雌二醇含量随水解程度的增加而增加,粘度随水解程度的增加而降低。     

大豆蛋白高水分挤压组织化过程中工艺参数对系统压力和扭矩的影响

以食用脱脂低温豆粕为原料,用响应面分析法,研究了DSE-25型双螺杆挤压机在大豆蛋白高水分挤压组织化过程中工艺参数对系统压力和扭矩的影响。结果表明,机筒温度、物料水分含量、喂料速度和螺杆转速等操作参数对挤压机系统压力和扭矩均具有显著的影响。系统压力随着机筒温度和物料水分含量的升高而降低,随着喂料速度的增加而增加,螺杆转速对其影响较小;扭矩随物料水分含量的增加而降低,随着机筒温度和螺杆转速的升高均表现出先升后降的趋势,随喂料速度的增加则表现出先降后升的趋势。依据逐步回归分析法建立的双螺杆挤压机系统参数的统计模型,具有较高的预测精度,可用于挤压过程的控制和挤压结果的预测。     

Extrusion Texturization of Air-Classified Pea Protein

Air-classified pea protein was texturized using a twin-screw extruder. The effects of moisture, screw speed and barrel temperature on the physical, functional and nutritional characteristics of texturized pea protein were investigated. Increased dough moisture increased product bulk density (BD) and available lysine (LYS) of texturized pea products, but decreased water-holding capacity (WHC) and in vitro protein digestibility (DIG). Raising the screw speed reduced BD and LYS of texturized pea protein, but increased WHC and DIG. Bulk density and LYS decreased as barrel temperature was increased, whereas WHC and DIG increased. Texturized pea protein resembled commercial texturized soy products with respect to most physical and functional properties.     

大豆蛋白高水分挤压组织化过程中操作参数对单位机械能的影响

以食用脱脂低温豆粕为原料,用响应面分析法,研究了DSE-25型双螺杆挤压机在大豆蛋白高水分挤压组织化过程中操作参数对单位机械能的影响。结果表明,机筒温度、物料水分含量、喂料速度和螺杆转速等操作参数对挤压机单位机械能均具有显著的影响。单位机械能耗(SME)随着机筒温度、物料水分含量和喂料速度的升高而降低,随螺杆转速的增加而增加;依据回归分析法建立的双螺杆挤压机系统参数的统计模型,具有较高的预测精度,可用于挤压过程的控制和挤压结果的预测。     

高压酶解大米蛋白抗氧化活性及其分子质量分布

以大米蛋白为原料,经不同压力(0.1、300、500 MPa)处理后,用Alcalase酶水解.以酶解物的还原力为指标,通过正交试验方法分别优化了3种压力条件下的酶解条件;用高效液相色谱分析了主要酶解产物的分子质量分布.结果表明,3种预处理蛋白在各自优化条件下制备的酶解物在1.0 mg/mL时的最大还原力分别为0.125、0.149、0.158.常压(即0.1MPa)对照组中10～15 ku、1～10 ku和1 ku以下等3段分子质量组分所占比例分别为26.6％、46.9％、26.5％;300 MPa和500 MPa组中的含量分别依次为16.5％、39.3％、44.2％和11.8％、33.1％、55.1％;可见,酶解物还原力大小与其分子质量的分布之间有一定的关联性.