糖玻璃化抗坏血酸胶囊制备的挤压工艺研究

采用挤压法制备糖玻璃化抗坏血酸胶囊,考察了挤压腔温度、螺杆转速和喂料速度对挤压过程中电机扭矩(扭矩百分比)、模头压力的影响.分析了挤压产品的还原性抗坏血酸含量、产率和挤压产品玻璃化转变温度等理化指标.结果表明:提高挤压腔温度、增加螺杆转速和降低喂料速度可以减小电机扭矩及模头压力.确定的挤压腔温度、螺杆转速和进料速度分别为中温(85℃-105℃-120℃-105℃)、60r/min和1.1 kg/h.该挤压条件下挤压产品中还原性抗坏血酸的载量15.76%～15.86%,产率大于98%.挤压产品的玻璃化转变温度高于40℃.     

挤压参数对薏米挤出产品物理特性的影响

利用双螺杆挤压机对薏米进行挤压加工,研究加工参数物料水分(12％～20％)、套筒温度(150～190℃)、喂料速度(4～20 kg/h)和螺杆转速(200～400 r/min)对模头压力、模头处产品温度、挤压机扭矩、比机械能、产品颜色等指标的影响.结果表明:随着水分的提高,产品温度、模头压力、比机械能、扭矩和产品的亮度下降,产品的比长度减小而产品的密度增加;随着温度的增加,模头压力、比机械能、扭矩和产品密度下降,而产品的温度上升,产品颜色变亮,产品的比长度增加;喂料速度的增加可以提高模头压力、扭矩、产品温度和膨化度,降低SME和产品密度;螺杆转速对产品温度和产品颜色和密度没有影响;压力和扭矩与红绿值(a*)和黄蓝值(b*)成负相关关系,且压力与产品的亮度(L*值)成正相关关系.     

基质对糖玻璃化甜橙油胶囊形成的影响

挤压法制备糖玻璃化胶囊是一种适合热敏性物质包埋的低温胶囊化方法。基质的选择是胶囊化中重要的影响因素。试验设定挤压腔各段温度分别为T1(65℃),T2(85℃),T3(105℃)和T4(95℃),螺杆转速为60r/min,喂料速度为1.2kg/h,以麦芽糊精及添加蔗糖和变性淀粉的麦芽糊精为基质,以甜橙油为芯材,制备糖玻璃化胶囊,考察不同基质对糖玻璃化甜橙油胶囊形成的影响。结果表明:所选配方挤压所得产品均以无定型形式存在。当以单一麦芽糊精为基质时,所得胶囊的玻璃化转变温度为48.52℃。在所选麦芽糊精基质的基础上,添加蔗糖和变性淀粉,所得胶囊的玻璃化转变温度分别降低和增加。热重分析表明,随着温度升高,胶囊的玻璃化结构逐渐被破坏,精油逐渐释放,其中复合基质比单一基质的芯材释放速度更慢,尤其是添加变性淀粉组。扫描电子显微镜结果表明,甜橙油主要以小液滴形式分散于玻璃化基质中。     

双螺杆挤压对沙米复合粉理化及糊化特性的影响

对沙米复合粉进行双螺杆挤压处理,全面探讨了不同挤压条件对仪器性能及产品特性的影响,为挤压膨化生产营养早餐粉及沙米的综合利用提供参考。结果显示:扭矩利用率和模头压力随螺杆转速、挤压温度、α-淀粉酶添加量增大而减少,随喂料速度增大有增大的趋势。加酶预处理使挤压复合粉的膨胀率和水溶性指数升高,吸水性指数略有下降,单位机械能显著低于未加酶样品。挤压后沙米复合粉颜色明显变暗,黏度值显著下降。综合考虑挤压机系统参数、膨化产品特性及挤压沙米复合粉的理化及糊化特性,选择螺杆转速为130 r/min、挤压温度为130℃、喂料速度为16 r/min、α-淀粉酶添加量为0.5%作为生产沙米复合营养早餐粉的较适宜加工条件。     

水热参数组合对大豆蛋白-鱼糜共混高水分挤压过程及产品品质的影响

高水分挤压技术是制备具有类似动物肉纤维结构和质地的新型植物基肉制品的前沿热点技术。本实验以大豆分离蛋白（soy protein isolate,SPI）和金线鱼鱼糜为原料（80∶20,m/m）,探究水热参数组合（物料水分质量分数65%、70%、75%,挤压温度125、135、145 ℃）对高水分挤压过程中单位机械能耗（specific mechanical energy,SME）和模口压力的影响,以及对挤出物品质的调控作用。结果表明：在实验所用水热参数组合条件下,高水分挤压过程中,鱼糜凝胶以颗粒形式填充在混合凝胶中,并会影响带有取向性的凝胶结构形成。物料水分质量分数增加的同时提高挤压温度会导致高水分挤压过程中的SME从783.40 kJ/kg显著降低到410.96 kJ/kg（P＜0.05）,模口压力从7.79 MPa显著降低到1.60 MPa（P＜0.05）。水热参数组合作用显著影响SPI-鱼糜混合挤出物的品质,与挤压温度相比,物料水分质量分数影响效果更为显著,当物料水分质量分数为70%、挤压温度为145 ℃时,挤出物组织化程度达到最大（2.36）。多项式拟合结果表明,水热参数组合条件下,高水分挤压过程中的SME和模口压力与SPI-鱼糜混合挤出物硬度、咀嚼度、凝胶强度、持水性和剪切力具有非线性相关关系。本研究可为实现植物蛋白和动物蛋白优势互补、开发动植物蛋白结合的替代蛋白类新产品提供参考和借鉴。     

膨化亚麻籽模头压力的变化规律研究

采用SLG67-18.5双螺杆挤压机优化亚麻籽挤压膨化工艺.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、喂料速度对模头压力的影响.研究结果表明,影响性能指标模头压力的因素主次关系为含水率、喂料速度、螺杆转速、温度,其中温度影响不显著.在实际生产中,需要着重考虑含水率和喂料速度、温度和含水率、温度和螺杆转速、温度和喂料速度的交互作用对模头压力的交互作用.     

玉米膨化食品加工参数研究

以玉米糁为材料，采用DSE-25型双螺杆挤压膨化实验室工作站为加工设备，分析了加工温度和物料含水量对扭矩、压力、膨化率和产品含水量的影响。结果表明，在试验设计的加工温度和物料含水量范围内，加工温度和物料含水量对螺杆扭矩、第4区压力、第5区压力、产品膨化率和含水量都有极显著影响。加工温度对第4区压力影响较大；物料含水量对扭矩、第5区压力、产品膨化率和含水量影响较大。随着加工温度上升，物料含水量增加，扭矩、压力、产品膨化率降低；随着加工温度升高，物料含水量下降，产品含水量降低。     

挤压糖玻璃化桔油胶囊的性质分析

采用挤压方法将桔油包埋于玻璃态的碳水化合物基质中。主要考察了挤压条件下(挤压腔四段温度分别为65℃-85℃-105℃-95℃)螺杆转速为60r/min,不同DE值的麦芽糊精壁材、糊精和蔗糖壁材对糖玻璃化胶囊形成的性质影响,结合差示扫描量热法、傅里叶变换红外光谱、粒径分析仪及扫描电镜等对胶囊的微观结构进行了表征。结果表明,在挤压过程中桔油能很好的包埋,芯材主要以小液滴的形式分散于包埋的基质中,粒径大小绝大部分为2~5μm。形成的糖玻璃化胶囊没有新的化学键形成,是以物理分散的形式存在。     

植物蛋白质高水分挤压技术研究现状

研究了植物蛋白质高水分挤压技术的现状.与低水分条件下挤压加工技术不同,高水分挤压产品组织化程度高.具有内的口感和外观.高水分挤压加工工艺中,挤压的温度、螺杆构型和模头形状对系统参教和目标参数都有影响.     

挤压法制备交联辛烯基琥珀酸木薯淀粉酯工艺与结构表征

采用挤压法研究了交联辛烯基琥珀酸木薯淀粉酯的工艺。探讨三偏磷酸钠、氢氧化钠、水分质量分数,以及出料温度和螺杆转速对交联淀粉酯乳化能力的影响,并对影响因素进行了正交优化。结果表明,在三偏磷酸钠质量分数1.0%,氢氧化钠质量分数0.6%,水分质量分数35%,出料温度120℃,螺杆转速110r/min的反应条件下,制备得到的交联辛烯基琥珀酸木薯淀粉酯的乳化能力可以达到58.56%。同时,采用红外光谱、电镜扫描和X射线衍射等手段对产物进行了结构分析和表征。     

Effects of Processing Conditions on Single Screw Extrusion of Feed Ingredients Containing DDGS

Distillers dried grains with solubles (DDGS), a feed coproduct from the fuel ethanol industry, has been shown to be a viable potential alternative protein source for aquaculture feeds. To investigate this, three isocaloric (3.5kcal/g) ingredient blends containing 20, 30, and 40% DDGS, with a net protein adjusted to 28% (wet basis, wb), were prepared for use as Nile tilapia feed. Extrusion processing was then conducted using three DDGS contents (20, 30, and 40%, wb), three moisture contents (15, 20, and 25%, wb), three barrel temperature gradients (90–100–100°C, 90–130–130°C, and 90–160–160°C), and five screw speeds (80, 100, 120, 140, and 160rpm) using a single screw laboratory extruder. Several processing parameters, including mass flow rate, net torque required, specific mechanical energy consumption, apparent viscosity, and temperature and pressure of the dough inside the barrel and die, were measured to quantify the extrusion behavior of the DDGS-based blends. For all blends, as the temperature profile increased, mass flow rate exhibited a slight decrease, die pressure decreased, and apparent viscosity exhibited a slight decrease as well. Likewise, the net torque requirement, specific mechanical energy consumption, and apparent viscosity decreased as screw speed increased, but mass flow rate increased. Additionally, as moisture content increased, die pressure decreased. At higher temperatures in the barrel and die, the viscosity of the dough was lower, leading to lower torque and specific mechanical energy requirements. Increasing the DDGS content, on the other hand, resulted in a higher mass flow rate and decreased pressure inside the die. As demonstrated in this study, the selection of suitable temperature and moisture content levels are critical for processing DDGS-based ingredient blends.     

Original article: Encapsulation of ascorbic acid in amorphous maltodextrin employing extrusion as affected by matrix/core ratio and water content

Ascorbic acid (AA) was encapsulated in glassy low‐dextrose equivalent maltodextrin matrix by extrusion. The effects of formulation parameters, i.e., core/matrix ratio and water content were mainly investigated on T_g of extrudate. The AA yield, AA content and water content of the products together with extrusion parameters were also determined and compared for different formulations. The T_g of extrudates containing water content from 7.860% to 10.430% ranged from 43.17 to 27.48 °C, and the T_g of extrudates which core to matrix from 1:4 to 1:8 ranged from 35.79 to 41.64 °C. AA yield of all extrudates is above 96%, and with increasing water content, there was a slight decrease in the AA yield. The increased water level and core/matrix ratio reduce specific mechanical energy and die head pressure. X‐ray diffraction and scanning electron microscopy suggested that AA was most likely molecularly dispersed within the maltodextrin indicating the miscibility of AA and maltodextrin.     

Effects of extrusion conditions on secondary extrusion variables and physical properties of fish, rice-based snacks

A formulation containing rice flour, fish powder, menhaden oil and vitamin E was extruded at a feed rate of 10 kg/h using a co-rotating twin-screw extruder. Primary extrusion (independent) variables were temperature (125-145 °C), screw speed (150-300 rpm) and feed moisture (19-23 g/100 g db). Response surface methodology (RSM) was used to study the effects of extrusion conditions on secondary extrusion variables (product temperature, pressure at the die, motor torque, specific mechanical energy input and mean residence time) and physical properties of the extrudates. Second-order polynomial models were computed and used to generate contour plots. Increasing feed moisture and screw speed decreased pressure at the die. Increased screw speed increased product temperature at the die but increased feed moisture lowered it. Increased barrel temperature, feed moisture and screw speed decreased motor torque. Increased screw speed increased specific mechanical energy, while increased feed moisture reduced it. Longer mean residence times were observed at lower screw speeds. Product density increased as feed moisture increased, but decreased with screw speed. Increased feed moisture decreased radial expansion.     

Effects of extrusion conditions on system parameters and physical properties of a chickpea flour-based snack

Response surface methodology (RSM) was used to study the effects of feed moisture content (16–18%), screw speed (250–320 rpm), and barrel temperature (150–170 °C) on extruder system parameters (product temperature, die pressure, motor torque, specific mechanical energy, SME) and physical properties (expansion, bulk density, hardness) of a chickpea flour-based snack. Second-order polynomials were used to model the extruder responses and product properties as a function of process variables. Product temperature and die pressure were affected by all three process variables, while motor torque and SME were only influenced by screw speed and barrel temperature. All three variables affected product responses significantly. Desirable products, characterized by high expansion ratio and low bulk density and hardness, were obtained at low feed moisture, high screw speed and medium to high barrel temperature. It was demonstrated that chickpeas can be used to produce nutritious snacks with desirable expansion and texture properties.     

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。     

Extruded Potato Peel Functional Properties Affected by Extrusion Conditions

Extrusion cooking of potato peel waste from processing plants to im-prove food safety affects functional properties of these peels as a high-fiber ingredient in foods. The effects of barrel temperature (104°C and 143°C) and feed moisture (31, 33.5, and 36% d.b.) on extruder performance and physical and functional properties of peels were studied. Torque and die pressure decreased with barrel temperature; all variables affected melt temperature. Samples were darker at the higher temperature. Expansion, Hunter a, and powder bulk density decreased with both variables. Hydration capacity increased with feed moisture. Extruded peels differed from commercial fiber products in color, but hydration capacity was similar among extruded peels and cereal brans.     

双螺杆挤压亚麻籽粕脱除生氰糖苷的研究

利用BrabenderDSE-25双螺杆挤压机对亚麻籽粕进行了挤压脱除生氰糖苷的试验,考察了加工条件(水分含量、加工温度、螺杆转速、喂料速度)对系统参数(扭矩、4区压力、5区压力)和脱毒效果的影响。结果表明,使用双螺杆挤压处理能达到使生氰糖苷降解脱毒的目的,合理的脱毒工艺参数:水分含量30%,加工温度80-120-130-140-150℃,螺杆转速120r/min,喂料速度18r/min,总氰化物脱除率为96.59%,生氰糖苷含量由257.85mg/kg降低至8.79mg/kg。     

Modeling Flow in Cylindrical Extruder Dies

Volumetric flowrate was studied in the die of a single screw extruder. Variables included the ratio of die length to die diameter, barrel to die diameter, barrel and die temperature, screw speed and product moisture. Die conductance was determined graphically and analytically. Results indicated that for a constant pressure drop across the die, increasing temperature, die diameter or moisture increased flowrate. Dimensional analysis was used to study the effect of each parameter on the flow through the extruder die. An expression for temperature rise due to viscous dissipation for isothermal flow in the die was developed and nomographs are presented.     

Extrusion of mixtures of starch and d-limonene encapsulated with β-cyclodextrin: Flavour retention and physical properties

d-Limonene was encapsulated with β-cyclodextrin to improve its retention during pre-added flavour starch extrusion. The objective of this work was to determine the effect of processing condition on the flavour retention and extrudate properties. Corn starch containing five levels of β-cyclodextrin-d-limonene capsules (0–5%) were extruded at five different maximum barrel temperatures (133–167 °C) and screw speeds (158–242 rpm) using a twin screw extruder. The effect of these parameters on the flavour retention, expansion, texture, colour difference (ΔE), Water Absorption Index, Water Solubility Index, and residence time distribution (RTD) were investigated. Barrel temperature and capsule level predominantly influenced flavour retention and extrudate properties, while screw speed primarily affected extruder performances such as torque, die pressure, specific mechanical energy and RTD.