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1.
高水分大豆蛋白组织化生产工艺和机理分析 总被引：15，自引：4，他引：15
以低温豆粕为原料，应用带冷却工艺的双螺杆挤压实验室工作站，开发出高水分组织化大豆蛋白产品的生产工艺；分析了螺杆转速、物料湿度、喂料速度和机筒温度等操作参数对产品质构和色泽的影响规律；利用扫描电镜对高水分组织化大豆蛋白产品的微观结构进行了观察和分析。结果表明：机筒温度在150℃左右时，产品具有较好的组织化度、色泽及口感；随着物料水分的增加，产品的组织化度、粘着性和明度指数逐渐增加，而硬度和咀嚼度逐渐降低；随着螺杆转速的增加，产品的组织化度、硬度、粘着性和咀嚼度均有增加的趋势；喂料速度对产品的表观形态影响较大，喂料速度较大时，产品表观粗糙、组织化度降低。单因素实验优选的操作参数为：机筒温度145℃～155℃，物料湿度45％～50％，螺杆转速90～160 r/min，喂料速度20～40 g/min。结合对生产工艺和产品微观结构分析，提出了高水分组织化大豆蛋白产品形成过程的“膜状气腔”理论假设，以供讨论和指导生产实践。 相似文献
2.
挤压法制备富钙强化重组大米的工艺优化及其结构表征 总被引：1，自引：1，他引：0
为提高碎粳米的利用率并制备出富含钙元素的重组强化大米,该文以粳米碎米为原料,添加乙酸钙作为强化剂,通过使用挤压法制备富含钙元素的重组强化大米。试验以钙强化大米质构特性为指标,对挤压工艺参数进行响应面优化,得到最佳工艺参数为:机筒温度100℃,螺杆转速85 r/min,质量含水率20.0%。在最佳工艺条件下得到的钙强化大米硬度为13.38N,弹性为0.67mm,黏着性为0.64m J,咀嚼性为851.51m J,接近普通粳米的质构特性,其钙质量分数为108.2 mg/(100g)。经X射线衍射表明强化米的结晶度明显减少,通过扫描电镜表征发现其外表面粗糙呈现不规则形状,并产生聚集现象,糊化温度降低。将其按1:12的比例添加到粳米中,钙质量分数为18.02 mg/(100 g),可提高人体对钙的摄入。 相似文献
3.
亚麻籽挤压膨化脱毒的工艺优化 总被引：2，自引：1，他引：2
采用SLG67-18.5双螺杆挤压机优化亚麻籽脱毒工艺。通过二次正交旋转组合设计试验，研究了温度、含水率、螺杆转速、喂料速度对亚麻籽中氰华氢(HCN)去除率的影响。单因素分析表明，亚麻籽中HCN去除率随温度升高、含水率增加、螺杆转速提高而升高；随喂料速度增加呈抛物线，中等喂料速度脱毒效果更好。利用频数分析法进行优化，得到亚麻籽中HCN去除率有95%的可能高于90%的参数范围，即膨化温度为147～153℃，亚麻籽含水率为13.8％～17.6%，螺杆转速为186～211 r/min，喂料速度为61.7～74.0 kg/h，从而为亚麻籽脱毒和开发利用及现有挤压膨化机的操作和调整提供了理论依据。 相似文献
4.
为缩短超高麦芽糖浆的生产周期、节约能源,该文系统地研究了挤压玉米粉作预处理后生产高麦芽糖浆的工艺,分析了机筒温度、螺杆转速、模孔直径及物料水分与麦芽糖含量、糖浆收率的关系。结果表明:挤压工艺的因素排序为机筒温度>物料含水率>螺杆转速>模孔直径;最佳挤压条件为:59℃、23%、200r/min、6mm,液化10min,糖化8h,经高效液相色谱分析,所制备的糖浆中麦芽糖质量分数为69.19%,糖浆收率可达100.62%,研究结果可为工业化生产麦芽糖提供数据参考。 相似文献
5.
挤压加工参数对重组米生产过程及产品膨胀度的影响 总被引：3，自引：1，他引：2
为了考察重组米生产过程中挤压加工变量对几种系统参数与产品膨胀度的影响,试验以杂交籼米（9?718品种）为原料,利用响应面模型,以螺杆转速、进料速度、进料含水率以及末端机筒温度为输入变量,以挤压系统参数（物料温度、模头压强、扭矩、比机械能和产品含水率）和重组米膨胀度为响应变量,探索在重组米生产过程中加工变量与系统参数及产品膨胀度的关系。结果表明,压强、比机械能和产品膨胀度都受到4个挤压变量的显著影响,但是物料温度受进料速度影响不显著,马达扭矩受末端机筒温度影响不显著,产品含水率仅受进料含水率的显著影响。比机械能与螺杆转速正相关,与进料速度、进料含水率和末端机筒温度负相关。所得二次回归模型均拟合良好,建立的挤压数学模型可应用于重组米生产,为重组米工业化生产的过程预测和产品性质预测提供参考。 相似文献
6.
水产沉性颗粒饲料挤压蒸煮工艺对其理化特性的影响 总被引：3，自引：2，他引：1
为了规模化生产出低污染、高转化率的环保型水产沉性颗粒饲料,选用双螺杆挤压机对水产全价配合原料进行挤压熟化研究。以沉性水产硬颗粒饲料理化特性(膨化度、近似密度、糊化度、耐久性和水中稳定性)为重要指标,采用表面响应分析法研究了物料含水率（22%～38%）、套筒温度（70～170℃）和螺杆转速（73～107?r/min）对其挤压工艺和饲料理化特性的影响规律,SEM分析其微观结构。结果表明：物料含水率、套筒温度和螺杆转速均显著影响饲料的理化特性。中高物料含水率和套筒温度及低螺杆转速时,才能获得理想的沉性高熟化水产颗粒饲料,其理化特性具有低膨化度（1.14）,高近似密度（757.6?g/L）、糊化度（879.5?g/kg）、耐久性（96.6%）和水中稳定性（88.7%）。SEM分析显示优化条件（物料含水率31%,套筒温度126℃,螺杆转速78?r/min）下生产的颗粒饲料结构光滑质密。该研究可为发展高效、低耗、低碳高品质沉性水产饲料研究和生产提供参考。 相似文献
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8.
试验以杂交籼米为原料,利用响应面模型,研究双螺杆挤压生产重组米过程中螺杆转速(60-180rpm)、进料速度(20-60g/min)、物料水分含量(22-42%)以及末端机筒温度(80-100℃)对挤压系统参数和重组米膨胀度的影响。结果表明,压强、比机械能和产品膨胀度都受到四个挤压变量的显著影响,但是物料温度受进料速度影响不显著,马达扭矩受末端机筒温度影响不显著,产品水分含量仅受进料水分含量的显著影响。比机械能与螺杆转速正相关,与进料速度、物料水分含量和末端机筒温度负相关。所得二次回归模型均拟合情况良好,,达到设计要求。可以认为本文建立的挤压数学模型可以应用于重组米生产领域,为重组米工业化生产的过程预测和产品性质预测提供一定帮助参考。 相似文献
9.
香菇双螺杆挤压膨化机的设计与试验 总被引：1，自引：0，他引：1
针对现有双螺杆挤压膨化设备生产香菇膨化产品时存在物料堵塞、预熟度低、作业参数缺失等问题而导致生产的产品膨化率低、吸水性差、硬度高等缺陷,该研究设计了一种香菇双螺杆挤压膨化设备,并对设备中的关键部件喂料搅拌防堵装置、预熟调质装置与双螺杆结构参数进行了设计与确定。同时,为探究设备中的作业参数对产品膨化性能的影响,研究了设备的螺杆转速、膨化温度、物料含水率对产品的膨化率、硬度、脆度、吸水性的影响。结果表明:影响膨化率的显著性顺序依次为螺杆转速、物料含水率、膨化温度;影响硬度的显著性顺序依次为螺杆转速、膨化温度、物料含水率;影响脆度的显著性顺序依次为膨化温度、物料含水率、螺杆转速;影响吸水性的显著性顺序依次为膨化温度、物料含水率、螺杆转速。其次,结合各因素交互作用的影响规律与目标优化结果,得出设备的最佳作业参数为:螺杆转速167.23r/min,膨化温度151.68℃,物料含水率16.83%,此时,产品的膨化率、硬度、脆度、吸水性分别为4.04%、18.61N、-8.46mm/cm^2、313.86%。将优化后的参数值在设备中进行了生产性应用,得到生产值与优化值的误差均小于4%,最大生产率为165 kg/h。与扬州大学机械工程学院实验室内的现有设备相比,在提高物料送料的连续性与调质熟化度的基础上,膨化率提高了25.00%,硬度降低了48.21%、脆度提升了40.55%、吸水性提高了62.35%。因此,该机的设计可为香菇膨化产品的开发提供了一种较为成熟的技术装备。 相似文献
10.
单螺杆挤压机对农产品加工因素的优化 总被引：17，自引：1，他引：17
在农产品和食品挤压机加工过程中,由于各种因素的变化,对产品的膨化质量有很大影响。通过挤压机螺杆与螺套之间的间隙、螺杆转速和物料含水率的变化,对产品的膨化指数,挤压机的生产率和功耗进行测定,分析在不同工况下挤压的工作情况以及产品特性。试验结果表明,影响试验指标的主要因素是螺杆与螺套之间的间隙,试验因素主次排列为间隙,含水率和转速,其较优组合为螺杆螺套之间的间隙0.75mm,螺杆转速300r/min,物料含水率18％。 相似文献
11.
亚临界丙烷萃取米糠油及其微量活性组分动力学模型 总被引：1，自引：1，他引：0
为了揭示亚临界流体萃取米糠油及其微量活性组分的动力学规律,该文以亚临界丙烷为萃取介质,研究了米糠油、γ-谷维素及α-生育酚等活性组分在不同萃取温度和时间的萃取率,并基于 Baümler 模型对目标物的萃取率进行模型拟合,建立相应的动力学模型并验证。结果表明,亚临界萃取过程中目标物的相对萃取率随时间增长递增,且在初始阶段（洗涤过程）的增长速率快于第二阶段（扩散过程）的增长速率;同时,升高萃取温度可同时提高目标产物的扩散系数和相对萃取率;基于Baümler模型可较好拟合亚临界丙烷萃取米糠油、γ-谷维素和α-生育酚的动力学过程（R2>0.95）,所得动力学模型具有较好的预测准确性。由Arrhenius方程可计算出米糠油、α-生育酚和γ-谷维素的亚临界萃取反应活化能,其中米糠油的活化能最低（5.23 kJ/mol）,α-生育酚次之（7.05 kJ/mol）,γ-谷维素最高（9.11 kJ/mol）,表明γ-谷维素最难萃取且对温度依赖程度最高;根据拟合所得动力学模型,对米糠油提取率进行预测,结果表明,该模型对米糠油萃取率的预测准确率达95.8%,而对γ-谷维素和α-生育酚萃取率的预测准确度稍低,分别达94.7%和94.4%,对三者均具有很好的预测准确性。总之,基于 Baümler 模型可以较好地建立米糠油及其有益伴随物的亚临界萃取动力学模型,从而较为准确的预测米糠油及其微量活性组分的萃取率,对米糠油的亚临界萃取工艺具有一定的理论指导意义。 相似文献
12.
Wheat flour with 0.3% (w/w) thiamin was extruded on a twin‐screw laboratory‐scale extruder (19‐mm barrel) at lower temperatures and expanded using carbon dioxide (CO2) gas at 150 psi. Extrusion conditions were die temperature of 80°C and screw speed range of 300–400 rpm. Control samples were extruded at a die temperature of 150°C and screw speed range of 200–300 rpm. Dough moisture content was 22% in control samples and 22 and 25% in CO2 samples. Expansion ratio, bulk density, WAI, and %WSI were compared between control and treatment. CO2 injection did not significantly increase expansion ratio. Bulk densities in the CO2 extruded samples decreased when feed moisture decreased from 25 to 22%. The products using CO2 had lower WAI values than products puffed without CO2 at higher temperatures. The mean residence time was longer in CO2 screw configurations than in conventional screw configurations. Thiamin losses were 10–16% in the control samples. With CO2, thiamin losses were 3–11% at 22% feed moisture, compared with losses of 24–34% at 25% moisture. Unlike typical high‐temperature extrusion, thiamin loss in the low‐temperature samples decreased with increasing screw speed. Results indicate that thiamin loss at lower extrusion temperatures with CO2 injection is highly dependent on moisture content. 相似文献
13.
The effects of moisture, screw speed, and barrel temperature on pasting behavior of refabricated rice grains were investigated in a corotating twin‐screw extruder with response surface methodology. The rice flour obtained from broken rice (≤1/8 of actual kernel size) of PR‐116 variety was used in the study. The screw speed was set at five levels between 49 and 150 rpm, barrel temperature between 59 and 110°C, and feed moisture between 31 and 45%. All pasting properties of refabricated grains evaluated—peak viscosity, hold viscosity, breakdown viscosity, final viscosity, and setback viscosity—were significantly (P < 0.01) affected by the three process variables. Barrel temperature was the most significant variable, with quadratic effect on all viscosity parameters. Response surface regression models were established to correlate the viscosity profile of refabricated rice grains to the process variables. The optimum moisture content, screw speed, and barrel temperature estimated by a response surface of desirability function for the production of refabricated rice were 36%, 130 rpm, and 89.5°C, respectively. Scanning electron microscopy also revealed that intermediate moisture and temperature along with high screw speed during extrusion could create a more realistic appearance of refabricated rice with less rupture of starch granules. 相似文献
14.
Brown rice flour was mixed with a Chinese medical plant (Euryale ferox Salisb.) and processed to make ready‐to‐eat breakfast cereals using twin‐screw extrusion. Levels of 15 and 20% feed moisture in flour, and 200 and 250 rpm screw speed were set, and the physicochemical properties and content of α‐, β‐, γ‐, and δ‐tocopherols were determined. The data showed that 15% feed moisture gave a low bulk density and water absorption index but a high expansion ratio and water solubility index. High screw speed (250 rpm) produced a result similar to that of 15% feed moisture. A sample with 85% brown rice flour with 15% E. ferox Salisb. retained the highest content of α‐, β‐, γ‐, and δ‐tocopherols (125, 6, 78, and 9 μg/g), respectively. The optimum extrusion conditions determined were 15% E. ferox Salisb. mixed with brown rice at 15% feed moisture and at 250 rpm screw speed. 相似文献
15.
挤压膨化大米做啤酒辅料的试验研究 总被引：12，自引：4，他引：12
该文通过实验室试验,研究了做啤酒辅料的大米挤压膨化系统诸参数(模孔孔径、套筒温度、物料含水率、螺杆转速),对醪液的主要考察指标(麦汁醪液的总还原糖、过滤速度)的影响规律,指出挤压膨化大米做啤酒辅料的可行性。 相似文献
16.
Mean residence time of rice flour in a twin‐screw extruder was determined using a blue tracer. Variables studied included moisture content, screw speed, barrel temperature, and screw configuration. Mean residence time increased with the increase of the barrel temperature and with the addition of reverse and kneading elements. Mean residence time was significantly related to screw speed, moisture content, die pressure, and screw configuration (P < 0.05). An empirical model was developed to predict mean residence time with the ability to reflect the changes of the barrel temperature and screw configuration. The effects of different extrusion operating conditions including screw speed, moisture content, barrel temperature, and screw geometry on the mean residence time were considered in the model. The validity of the developed model was extensively evaluated and verified using different screw geometries and other processing variables. The mean residence times predicted by the developed model are in good agreement with the experimental data. 相似文献
17.
《Cereal Chemistry》2017,94(5):903-908
Infrared‐stabilized rice bran was substituted into Turkish noodles (erişte) at the levels of 10, 20, and 30%, and the effects of the incorporation on proximate composition, color, cooking properties, thiamin and riboflavin contents, mineral composition, and sensory and textural properties were investigated. Crude fat, protein, dietary fiber, B vitamins, Mg, K, P, Mn, Ca, and Se contents of the noodles increased significantly with increasing substitution level (P < 0.05). Optimum cooking time increased with increasing levels of incorporation. Swelling volume and water absorption of the noodles substituted with 20 and 30% rice bran increased significantly (P < 0.05). However, cooking loss was not significantly affected by the substitution. The effect of rice bran inclusion was insignificant on hardness (P > 0.05), whereas adhesiveness, cohesiveness, and springiness of rice bran substituted noodles were significantly lower when compared with the control (P < 0.05). Structure/texture, taste/flavor, and overall acceptability scores of the control noodles and the noodles substituted with rice bran at the level of 10% were not significantly different (P > 0.05). However, substitution levels higher than 10% negatively affected the sensory scores. 相似文献
18.
F. Martínez-Bustos Y. K. Chang A. C. Bannwart M. E. Rodríguez P. A. Guedes E. R. Gaiotti 《Cereal Chemistry》1998,75(6):796-801
The effects of added calcium hydroxide (0.0, 0.15, 0.25, and 0.35%) and processing conditions, feed moisture content (mc) (16, 18, and 20%) and barrel temperature (130 and 150°C) on characteristics of corn meal extrudates were studied. Extruder screw speed was maintained at 130 rpm. Corn meal was extruded with a single-screw extruder (Brabender model GNF 1014/2) with a screw compression ratio of 3:1. The highest values (P < 0.05) for radial expansion and the lowest values for density and breaking force of extrudates were found for the treatment with 0.00% calcium hydroxide extruded at 16% feed mc and 130°C barrel temperature. This treatment was statistically different from the other treatments. Best values for radial expansion of samples extruded with added calcium hydroxide were for the samples with 0.15% calcium hydroxide at 18% feed mc and 130°C barrel temperature, followed by the sample with 0.35% calcium hydroxide at 16% feed mc and 130°C barrel temperature. Water absorption index and water solubility index were affected by calcium hydroxide and extrusion conditions evaluated. Extrudates had large numbers of flattened and sheared granules. Increases in calcium hydroxide increased extrudate yellowness. The combined action of calcium hydroxide and extrusion conditions completely modified the organized structure of the starch and suggest the formation of a starch-calcium complex (crystalline region). The texture of the extruded products was crispy after puffing. 相似文献
19.
The residence time distribution and barrel fill of pet food in a twinscrew extruder was determined under conditions of a constant ratio of feed rate to screw speed. Specific feeding load was held constant at 0.16 kg/hr/ rpm while feed rate ranges were 24–56 kg/hr and screw speed ranges were 150–350 rpm. The residence time rapidly decreased as feed rate and screw speed increased. The spread of the residence time distribution (RTD) was smaller at higher feed rates and screw speed, however analysis of the normalized RTD indicated greater mixing. The barrel fill was constant at ≈50% throughout the range of experimental conditions. 相似文献