蛋白质在挤压蒸煮过程中的变化

蛋白质在挤压蒸煮过程中的变化前言蛋白物料的挤压蒸煮是现代比较先进的加工工艺，第一篇关于植物蛋白组织化的专利登记于１９６６年。挤压蒸煮的优点很多，但作为它的一项专门用途，即用在植物蛋白肉的制造上并没达到人们预期的结果。尽管需考虑的因素很多，包括经济因素...     

数学分析在蒸煮挤压过程研究中的应用

食品的蒸煮挤压加工是一个非常复杂的过程，很难用任何单一因素来研究这一过程。本文介绍一种系统分析方法在这一复杂过程研究中的应用。     

挤压蒸煮技术在变性淀粉生产中的应用

主要阐述了挤压加工原理,以及用挤压机作反应器生产氧化、酯化、交联和醚化等多种类型的变性淀粉,并对其相关性质进行了简要分析。认为挤压蒸煮技术是快速、连续生产多种变性淀粉的一种经济可行的方法。     

挤压蒸煮技术在变性淀粉生产中的应用

主要阐述了挤压加工原理,以及用挤压机作反应器生产氧化、酯化、交联和醚化等多种类型的变性淀粉,并对其相关性质进行了简要分析。认为挤压蒸煮技术是快速、连续生产多种变性淀粉的一种经济可行的方法。      

挤压蒸煮技术在富含纤维素产品中的应用

挤压蒸煮技术是近年来发展较快的现代食品工程技术之一。膳食纤维经挤压蒸煮处理后 ,可提高膳食纤维的可溶性 ,改善其活性功能 ,在食品工业中有更广泛的应用前景。     

蛋白质在挤压蒸煮过程中的变化（续）

蛋白质在挤压蒸煮过程中的变化（续）４．蛋白质交联──非二硫键挤压过程中非二硫共价键引起蛋白键的连接有三种可能：赖丙氨酸（Ｌｙｓｉｎｏａｌａｎｉｎｅ）与硫氨酸的分子间交联、美拉德反应、异肽键连接等（见图２）。１．正常的肽键２．分子间的交联（１）ＬＡＬ型...     

蒸煮挤压与超细粉碎技术在豆渣产品开发中的应用研究

对超细粉碎与蒸煮挤压技术作了简要的介绍。结合豆渣产品的开发，将二者有机地结合并运用到豆渣深加工产品中。     

蒸煮挤压与超细粉碎技术在豆渣产品开发中的应用研究

对超细粉碎与蒸煮挤压技术作了简要的介绍。结合豆渣产品的开发,将二者有机地结合并运用到豆渣深加工产品中。     

挤压蒸煮对营养物的影响

当今各种形式的挤压工艺被广泛地用于传统产品和现代产品的生产。挤压技术以其用途广泛和经济性这两个突出优点,使其在食品工业上的应用范围不断扩大。因此,人们对挤压蒸煮对产品营养的影响进行了大量的研究。总的来说,研究结果可以消除人们因食用挤压产品而对健康方面的担心。挤压蒸     

In-vitro iron dialysability from legumes: Influence of phytate and extrusion cooking

In-vitro iron dialysability from five Italian legumes (mottled bean, white bean, faba bean, chickpea, lentil) and the influence of phytate and extrusion cooking on it were evaluated. Iron dialysability was 2·3 and 2·4% in mottled and white bean respectively, 1·2% infaba bean, 2·7% in chickpea and 1·1% in lentil. After extrusion cooking the flours showed a marked iron contamination and a decrease in iron dialysability, but these changes were significant only for mottled bean. Enzymic phytate removal induced an increase in iron dialysability > 100% in all the raw legumes except mottled bean which showed an increase of only 57%. This finding indicates that, although phytate consistently modifies iron dialysability, it is difficult to identify a quantitative relationship between phytate content and iron dialysability.     

Continuous emulsification and gelation of dairy ingredients by HTST extrusion cooking: production of processed cheeses

Processed cheese was prepared batchwise and by extrusion cooking. The cheddar-based cheese mix contained varying amounts of polyphosphate ions, rework, lipids, water and/or non cheese proteins. The extrusion conditions (barrel temperatures, screw speed and screw profile) were also varied. The texture, structure and colour characteristics of batch and extrusion-processed cheeses were evaluated using penetrometry, scanning electron microscopy and reflectance measurements. The degree of fat emulsification was assessed and the proportion of casein nitrogen sedimentable by ultracentrifugation was determined, as a means of following micellar disruption plus casein restructuring due to extrusion and to the additional creaming step. Results indicate that extrusion cooking can be used to continuously mix, melt, emulsify and gel the cheese mix constituents, and that processed cheeses or cheese analogues of varying texture (spreadable to sliceable) can be obtained, with a mean residence time in the extruder of about 100 seconds.     

基于挤压蒸煮的荞麦粉加工品质改良及其机制研究

文章分析了挤压蒸煮对荞麦粉室温黏度和凝胶特性的影响,并利用体积排阻色谱测定了淀粉的分子量分布,探讨预糊化处理改善荞麦粉凝胶特性的机制;基于面带质地评价方法,优化预糊化荞麦粉在50%荞麦挂面中的添加比例。结果表明:荞麦粉经挤压蒸煮后,常温水中可形成凝胶;室温黏度显著增加;在主区温度200℃,水分含量18%,螺杆转速220r/min的条件下,所得预糊化荞麦粉中聚合度(DP)为6～50的支链淀粉分子最多,且此时凝胶强度最大。当预糊化荞麦粉添加量为10%时,面带抗拉能力最佳,黏附能力适中。由此可见,预糊化荞麦粉中特定链长的支链淀粉分子(DP 6～50)与凝胶品质呈正相关;50%荞麦挂面中添加适量预糊化粉可显著改善挂面的加工性能。     

改良挤压技术制备低蛋白质构米的研究

以粳米淀粉为原料,使用改良挤压技术制备低蛋白质构米,利用响应面分析法考察加工参数如物料含水率、螺杆转速和机筒温度的变化对低蛋白米质构特性的影响,并且以粳米的质构指标为参考指标,优化低蛋白质构米的制备工艺。结果表明,最优工艺参数为物料含水率35%,螺杆转速30r/min,机筒温度(糊化区温度)120℃,该工艺条件下,低蛋白质构米的硬度为(9 122±244)g,黏性为(-983±49)g.s,弹性为0.67±0.05,接近粳米的质构特性(硬度为(8 996±196)g,黏性为(-627±41)g.s,弹性为0.62±0.03)。同时,与粳米相比,其蛋白质含量非常低,为0.43%±0.01%,而且外观和色泽接近市售粳米,米粒完整,颜色均一,圆润光滑,轮廓分明,米质结构紧密。     

热塑挤压蒸煮处理技术对大豆蛋白基本特性的影响

利用双轴挤压蒸煮处理技术对大豆蛋白进行处理,从质构特性、功能特性及营养特性等三方面对挤出物的组织化效果进行研究。以三个挤压操作参数供水率、螺杆转速和腔体温度为输入参数,挤出物的最大剪切力、复水率、持水率和蛋白质体外消化率为响应参数,探索挤压蒸煮系统操作参数对大豆蛋白质基本特性的影响规律,统计分析表明,三个挤压操作参数与响应参数之间存在显著的相关关系,所得拟合回归模型具有较高的可信度。挤压蒸煮处理操作参数对大豆蛋白的组织化效果有明显影响。     

Thiamine destruction during extrusion cooking as an indicator of the intensity of thermal processing

Assessment of the intensity of high temperature-short time (HTST) extrusion cooking was studied by measuring the extent X_A of thiamine destruction. Small quantities of thiamine hydrochloride (0.1–0.7 g per 100 g) were mixed with wheat flour (containing ∼ 14% water) prior to extrusion experiments. Results indicate that thiamine destruction follows an apparent first-order reaction and that the rate constant K of destruction, calculated from near isothermal extrusion experiments at 133, 142 or 152°C (product temperature), follows an Arrhenius relationship with an activation energy of 49.9 kJ/mol.
K values were calculated from experimental determination of X_A and of the residence time distribution (RTD) in the effective heating zone of the extruder.
The influence of product temperature (just before the die), water content during extrusion and speed of screw rotation on the overall K (for non-isothermal extrusion experiments) was determined and analysed by multiple regression. Results show that thiamine destruction X_A can be predicted by means of a linear mathematical model.
Each experimental X_A value can be used, in combination with Arrhenius equation constants and RTD, to express a given extrusion process in terms of equivalent isothermal temperature and equivalent plug flow residence time.     

西农黑大穗小麦挤压膨化加工研究

以普冰9946小麦为对照,研究西农黑大穗挤压膨化过程中加工温度、物料含水量、喂料速度变化对挤压膨化的扭矩、4区压力、5区压力、单位机械能耗、产品比容、径向膨化率、脆度、硬度的影响。结果表明,在试验范围内,温度为T1时,西农黑大穗产品比容、径向膨化率高,单位机械能耗高;温度为T3时,产品脆度高、硬度低,膨化率低。含水量为20%时,产品物理特性相对较好;含水量为22.5%时,单位机械能耗较低。喂料速度为20 g/min时,产品物理特性较好,单位机械能耗较高。加工过程中,西农黑大穗的扭矩、压力均高于对照,单位机械能耗和产品物理特性与对照差异极显著(P0.01)。     

生姜汁在烹饪中的应用

生姜是日常生活和烹饪中不可或缺的调味品，也是一种重要的香辛调味料。生姜汁是从生姜中制取出来的汁液，用生姜汁来取代生姜可以为烹饪活动带来很多便捷和好处。围绕这些方面介绍了几种常用的生姜汁制取方法，生姜汁在烹饪中的应用以及使用注意事项等。