鱼糜在挤压过程中流变特性的初探

文章研究了鱼糜在挤压过程中的流变特性，建立了在不同压力下的流变模型，并分析了鱼糜表观粘度随压力而变化的原因     

新西兰蜂蜜、昆山洋槐蜜与南京市售蜂蜜流变特性比较

本文从下列三方面对新西兰翘摇蜜、我国昆山洋槐蜜(原拟出口)与南京市售洋槐蜜、紫云英蜜的流变特性进行比较:(一)流变模型和流变参量。(二)流变参量随温度变化的规律。(三)触变性,并对产生这些差异的原因作出解释。     

果品静载流变特性的研究进展

本文通过对国内外各类果品的静载压缩流变特性研究现状的分析，指出了在果品的静载流变学研究领域内存在的主要问题，提出了今后果品流变学研究中需要加强和进一步研究的内容：1)加强对采后各阶段受压时果品的微观组织结构、生理生化过程的变化以及储运环境温度等因素与流变损伤效应的交叉性影响的研究； 2)加强对实际储运中较多出现的多果接触、受压问题的系统性研究；3)重视研究储运受压后流变损伤的发展与果品储藏品质关系的研究；4)根据国内外生产实际，应加强特色果品的流变学研究,像西瓜、甜瓜等，既具有较高的营养价值和经济价值，又在世界范围内广泛种植。同时，提出了以果品本身的粘弹性为依据，在ADAMS软件平台上利用计算机虚拟样机技术建立流变学模型并获得相应参数的新方法。     

Rheological Characteristics of Domestic Honeys

采用流变学方法对国产蜂蜜流变特性进行了研究。流变试验数据分析表明国产蜂蜜流变模型为Ｎｅｗｔｏｎ体，而非过去所认为的Ｂｉｎｇｈａｍ体。影响国产蜂蜜粘度的诸因素中，水分的影响最为显著。建立了国产蜂蜜ｗ－ｔ－η图，以充分描述其水分、温度与粘度之间的各种关系     

国产蜂蜜流变特性研究(英)

采用流变学方法对国产蜂蜜流变特性进行了研究。流变试验数据分析表明国产蜂蜜流变模型为Ｎｅｗｔｏｎ体，而非过去所认为的Ｂｉｎｇｈａｍ体。影响国产蜂蜜粘度的诸因素中，水分的影响最为显著。建立了国产蜂蜜ｗ－ｔ－η图，以充分描述其水分、温度与粘度之间的各种关系     

几种厌氧消化原料的流变特性及其影响因素

考察了6种厌氧消化原料的流变特性,研究了物料浓度、温度和发酵时间等因素对流变特性的影响,以期为厌氧消化工艺的设计及设备选用提供基础参数。结果表明,猪粪、鸡粪、牛粪、羊粪、鸭粪、兔粪原料均为假塑性流体,且符合幂率方程。随浓度增加原料黏度升高,流变指数降低。随着温度的升高,鸭粪、牛粪、鸡粪的黏度呈线性趋势降低,流变指数升高;猪粪、羊粪、兔粪的黏度呈现先减低后升高的趋势。计算得到鸭粪、牛粪、鸡粪的活化能分别为8.018,11.337,8.285 kJ/mol。随着发酵的进行,鸭粪的黏度下降,趋势与TS（总固体）含量变化基本一致,猪粪、羊粪和牛粪黏度呈现上升的趋势,鸡粪与兔粪的黏度变化不明显。     

基于流固耦合渗流的植物油料压榨数值模拟

考虑植物油料的可变形和流变,植物油料的压榨过程是一个渗流场和流变场耦合渗流问题。基于流固耦合渗流理论建立植物油料压榨过程的模拟模型,采用有限差分法和有限元法交替求解渗流场和流变场。数值模拟了压榨过程中菜籽和菜籽仁油料的位移、菜籽仁孔隙流体压力分布与消散、有效应力分布与变化。菜籽和菜籽仁的位移数值解和实测值比较吻合,尤其在中、后时段。     

低浓度甘蔗渣化学浆流变特性的研究

该文对不同浓度、打浆度、剪切速率对低浓度甘蔗渣化学浆流变特性的影响进行了实验研究,对不同因素引起浆料表观黏度变化的机理进行了分析,结果表明：随浆料浓度增加,纸浆表观黏度呈指数式增加;打浆度影响浆料的微观结构,随打浆度升高,纸浆表观黏度呈下降趋势;低浓度纸浆的表观黏度随剪切速率提高而递减。在实验测量范围内,甘蔗渣低浓度纸浆为满足幂律关系的非牛顿流体,拟合的本构方程的流变特性指数n<1,因此其在测量范围内为拟塑性流体。另外,随着纸浆浓度的降低,流变特性指数n增加,表明随低浓度纸浆逐渐变稀,所表现出的流变特性向着牛顿流体的方向趋近。低浓度纸浆流变特性的研究为纸浆模塑生产线流送系统提供了设计基础。     

甘薯粉团的触变性研究

针对传统的粉丝加工过程中粉团所表现出的流变性质,作者用NXS—11型旋转粘度计对粉团的触变性进行了初步的测定和研究。通过回归分析,建立起粉团在触变条件下的流变模型方程并探讨了粉团含水量、含芡量对粉团触变性的影响以及粉团的表观粘度随剪切时间变化的一般性规律。     

莲藕粉糊的流变特性实验研究

为了研究莲藕粉糊的流变特性参数，以开发莲藕方便食品，采用一套同心圆筒旋转粘度仪测绘了不同浓度、粒度、pH值条件下莲藕粉糊的流变特性曲线，并对浓度、粒度、pH值和温度对莲藕粉糊流变学行为的影响进行了分析研究。结果表明，浓度从2%增至10%时，稠度系数从0.434增至20.302。建立了表观粘度随浓度的变化规律的回归方程，其相关系数高达0.9931。     

鱼糜微结构与其流变特性相关性的研究

鱼糜的流变特性与其微结构密切相关,而对微结构与其流变特性参数间的定量描述却很少有人探讨。文章用偏最小二乘法建立了鱼糜微结构与其流变特性之间相互关系的定量描述,检验结果表明该关系方程是合理的。     

鱼糜团聚结构的随机分形模拟初探

鱼糜团聚结构影响其流变特性。用计算机模拟鱼糜团聚结构可以直观地揭示鱼糜团聚结构对其流变特性的影响。用随机分形初步模拟静态鱼糜团聚结构,得出了可模拟静态鱼糜团聚结构的修正ＤＬＡ模型。     

金鲳鱼肉和罗非鱼皮明胶改善罗非鱼碎肉鱼糜品质

为了改善罗非鱼碎肉鱼糜制品的品质,研究添加金鲳鱼肉和罗非鱼皮明胶对罗非鱼碎肉鱼糜制品品质的影响。将少量金鲳鱼肉与罗非鱼碎肉混合,制作成鱼糜(金鲳鱼肉质量分别占复合鱼糜总质量的0%、5%、10%、15%、20%),研究鱼糜制品品质的变化规律。通过检测样品的质构、凝胶强度、出水率及颜色发现,随着复合鱼糜中金鲳鱼肉含量的上升,复合鱼糜制品的硬度、胶着性、咀嚼性、弹性、内聚性、凝胶强度、白度均呈现上升趋势,但出水率无显著变化。进一步研究,将罗非鱼鱼肉和金鲳鱼鱼肉以一定比例混合,制作成复合鱼糜,然后加入不同量的明胶,研究复合鱼糜制品品质的变化规律发现,将明胶添加到复合鱼糜制品中会使鱼糜制品的硬度、胶着性、咀嚼性、凝胶强度、白度均上升,出水率下降,但鱼糜的弹性、内聚性、破断距离等差异不显著。试验结果表明,金鲳鱼肉和罗非鱼皮明胶可以用于罗非鱼碎肉鱼糜制品品质的改良。研究结果为改善罗非鱼碎肉鱼糜制品的品质提供了参考。     

Contributions of blood and blood components to lipid oxidation in fish muscle.

There was a wide variation in the amounts of hemoglobin extracted from the muscle tissue of bled and unbled fish. Averaged values suggested that the residual blood level in the muscle of bled fish was substantial. Myoglobin content was minimal as compared to hemoglobin content in mackerel light muscle and trout whole muscle. Hemoglobin made up 65 and 56% of the total heme protein by weight in dark muscle from unbled and bled mackerel, respectively. Bleeding significantly reduced rancidity in minced trout whole muscle, minced mackerel light muscle, and intact mackerel dark muscle but not minced mackerel dark muscle stored at 2 degrees C. The reduction was in the number of fish that had a longer shelf life; muscle from certain bled fish had rancidity that was comparable to the rancidity in unbled controls. The soluble contents of erythrocytes accounted for all of the lipid oxidation capacity of whole blood added to washed cod muscle. Limiting lysis of erythrocytes delayed lipid oxidation, which was likely due to keeping hemoglobin inside the erythrocyte. Apparent breakdown of lipid hydroperoxides occurred only when a critical level of hemoglobin was present. Blood plasma was slightly inhibitory to oxidation of washed cod lipids. These studies suggest that blood-mediated lipid oxidation in fish muscle depends on various factors that include hemoglobin concentration, types of hemoglobin, plasma volume, and erythrocyte integrity.     

Added triacylglycerols do not hasten hemoglobin-mediated lipid oxidation in washed minced cod muscle

Hemoglobin-mediated lipid oxidation in washed, minced cod muscle was related to the triacylglycerol to membrane lipid ratio. The same rapid development of thiobarbituric acid reactive substances (TBARS) and painty odor occurred with and without the presence of up to 15% menhaden oil. Without hemoglobin, development of TBARS and painty odor was slow, despite a high amount of hydroperoxides in samples with oil added (1135 micromol/kg muscle). This suggested that hemoglobin reacted by cleaving preformed hydroperoxides into secondary oxidation products. Nearly doubling the hemoglobin concentration approximately doubled the extent of lipid oxidation with and without added oil. This indicated that hemoglobin was limiting for the oxidation reaction. The noneffect of added oil suggests that membrane lipids and/or preformed membrane lipid hydroperoxides provided sufficient substrate in hemoglobin-catalyzed oxidation of washed minced cod muscle. Fe(2+-)ADP did not induce any oxidation of washed minced cod with/without added oil. Results suggest that lipid oxidation in fatty fish may be more related to the quantity and type of the aqueous pro-oxidant and the membrane lipids than to variations in total fat contents.     

Rheological behavior of WPI dispersion as a function of pH and protein concentration

Physical and flow properties of proteins can provide information necessary for the optimal design of unit processes and quality control of the manufacturing process and final products. Therefore, the purpose of this investigation was to characterize the rheological behavior of a whey protein isolate (WPI) (BiPRO) dispersion as a function of pH and protein concentration. A rotational viscometer was used to determine the apparent viscosity, shear rate, and shear stress of WPI dispersions. Both the consistency index (k) and the flow behavior index (n) were sensitive to changes in pH and protein concentration. Mathematical relations obtained from experimental values of k and n allowed the determination of a model for apparent viscosity (eta) of WPI dispersions as a function of pH and protein concentration. At 5 and 10% BiPRO, whatever the pH, the rheological behavior appeared to be a newtonian fluid, while at 20% BiPRO, the rheological behavior appeared to be a nonnewtonian pseudoplastic fluid. Furthermore, at 20% Bipro, the apparent viscosity presented an increase in viscosity from 5.6 to 5.4, followed by a decrease from pH 5.4 to 5.0 at all shear rates. The highest viscosity was obtained at 20% pH 5.4, with an approximate value of 0.25 Pa.s, 10 times higher than the one obtained at 5 and 10% BiPRO.     

棉籽粉流变特性的研究

用毛细管流变仪研究了棉籽粉的流变特性。实验结果表明：棉籽粉呈现很强的非牛顿性，剪切速率、温度和含水率对表观粘度影响显著；表观粘度随剪切速率的增大而减小，随温度的升高而减小，随含水率的增大而减小。文中还提出了棉籽粉的粘度模型和半经验公式。