燕麦籽粒挤压工艺的优化

为了提高燕麦加工的工业化程度和产品质量,利用双螺杆挤压机对燕麦籽粒进行了挤压加工,结合响应面设计建立了辅料添加量、蒸煮时间及螺杆转速与产品特性之间的回归模型;测定了燕麦籽粒挤压产品的膨化率、表面积、色泽、质构、感官总分、脂肪及蛋白质含量等指标,通过因子分析法得到综合评分,结合响应面分析得到燕麦籽粒挤压加工的最优工艺参数。结果表明,燕麦籽粒的脂肪含量与其挤压产品的品质成反比;浸泡结合蒸煮处理可以有效提高原料含水量,进而提高挤压产品质量;综合评分影响因素为淀粉添加量＞螺杆转速＞蒸煮时间;燕麦籽粒挤压工艺最优参数为螺杆转速300 r·min^-1,蒸煮时间5 min,添加淀粉量20%。     

低温挤压加酶脱胚玉米粉生产酒精试验

研究低温挤压加酶脱胚玉米粉,直接液化、糖化、发酵、蒸馏生产酒精技术,并考察了脱胚玉米粉挤压前耐高温α-淀粉酶添加量、挤出物糖化时糖化酶添加量、糖化时间、液化时耐高温α-淀粉酶添加量、发酵时酵母添加量对醪液的主要考察指标(醪液的酒精度、淀粉出酒率、残总糖)的影响规律.结果表明,本研究的挤压-糖化-发酵系统主要参数优化值对应的醪液发酵48 h的酒精度、淀粉出酒率分别为13.45%和59.21%,高于对照挤压不加酶脱胚玉米醪液的对应值13.08%和57.85%,也高于脱胚玉米传统酒精生产工艺醪液的对应值12.89%和56.6%.     

SDP-45小型单螺杆膨化机改进研究

为进一步开发膨化食品新产品,优化膨化食品原料和配方,对实验室原有的SDP-45小型单螺杆膨化机进行改进,旨在提高实验设备的利用率,并减少实验过程中原料过多的浪费。为此,介绍了SDP-45小型单螺杆膨化机在生产大豆组织蛋白时所遇到的问题,对该机不足之处进行改进,使之达到试验要求。     

鱼肉蛋白质组织化方法的研究与应用

作者介绍了国内外鱼肉蛋白质组织化研究的发展与现状,并对五种现有的组织化方法进行了讨论,提出热塑挤压用于鱼肉蛋白质组织化最具有发展潜力。     

微波辅助提取大豆甙元工艺研究

大豆甙元是大豆中一种生理活性物质,挤压技术和微波提取技术对其提取效果影响尚未见报道.本文研究挤压膨化技术对大豆甙元提取的影响,并确定最佳的微波提取条件.在考察液料比、微波时间等单因素对大豆甙元得率影响的基础上,选取微波时间、料液比和浸置时间进行三因素三水平的响应曲面试验,以确定微波辅助提取大豆甙元最佳条件.并以微波辅助提取未经挤压的大豆、挤压处理过的大豆用乙醇作为溶剂提取、未挤压未微波的大豆中大豆甙元得率作为对照.试验结果表明微波辅助提取大豆甙元的最佳条件为乙醇浓度为90%,提取时间为5 min,微波火力为0.6,提取液pH为2,液料比(V/W)为30,提取1次.得率为0.26%,显著高于对照试验.挤压膨化技术处理有利于大豆甙元的提取,微波技术提取大豆甙元效果优于对照.     

Functional suitability of commercially milled rice bran in India for use in different food products

The effect of blending of commercially available full fat and defatted rice brans in India from modern multistage rice mills with parboiling/stabilizing facilities in different food products in comparison to those obtained from laboratory milling of rice is reported. Bread volume and cookie spread decreased but muffin volume increased with the addition of different types of bran to wheat flour, however, the cookie spread factor was not affected by addition of full fat rice bran. The yields of the extrudate were increased by the blending of full fat rice bran but were decreased by the addition of defatted rice bran. Rice brans could be added to different food products to the extent of 5–10%. However, the full fat rice bran could not be used for production of extruded snack food.     

Fabrication and characterization of oat flour processed by different methods

The properties of oat flour can be manipulated by processing to suit various consumption and product development needs. In this work, three different processes typically used on oat flour, namely the extrusion, drum drying and enzyme-treatment spray drying process were evaluated with respect to how each process changes the quality of the oat flour. Results showed that the extrusion process produced oat flour with the best flow ability while the enzyme-treated spray drying process led to the lowest flowability. The color of enzyme-treated spray-drying oat flour was the brightest while the oat flours turned darker after extrusion and drum drying. In addition, drum dried oat flour had the highest capability to hold water. In terms of particle size distribution, the extruded and drum dried oat flour showed smaller particle size and the particle had less complete and irregular surfaces. On the other hand, the enzyme-treated spray-drying samples showed the best particle uniformity and sphericity. The viscosity of all the treated oat flour decreased with increasing shear rate, indicating the shear thinning behavior, and a weak gel-like behavior with very high viscosity was obtained via drum drying. The results reported here can be useful and provide a baseline to fully understand how the oat flour properties changes with different processing methods to offer a wider opportunity in using oat flour for food product fortification and design.     

低温挤压脱胚玉米辅料啤酒麦汁中糖组分的测定

[目的]准确测定麦汁中可发酵糖的组成及含量。[方法]采用高效液相色谱法(HPLC)测定低温挤压膨化脱胚玉米辅料啤酒麦汁中的可发酵糖组成及含量。[结果]麦汁中果糖、葡萄糖、蔗糖、麦芽糖以及麦芽三糖的含量分别是3.8、7.4、4.2、53.8和10.6 g/L。5种糖的浓度与其峰面积在检测范围内呈良好的线性关系,相关系数为0.977 6～0.990 7,相对标准偏差为1.27%～3.26%,样品的加标回收率均大于96%。[结论]该方法简便快速、灵敏度高、重现性好,为测定脱胚玉米辅料啤酒麦汁中可发酵糖的组成提供了准确可靠的分析方法。     

Physical and nutritional qualities of extruded weaning foods containing sorghum,pearl millet,or finger millet blended with mung beans and nonfat dried milk

Sorghum, pearl millet, and finger millet flours (60% of each) were blended with toasted mung bean flour (30%) and nonfat dry milk (10%) and extruded (Brabender single screw) to make precooked, ready-to-eat, weaning foods. The extruded foods had high cold paste viscosity, but their cooked paste viscosity was lower than that of the respective blends. Chemical scores of the extruded foods were 78 for sorghum, 80 for pearl millet, and 96 for finger millet. Protein digstibility corrected amino acid scores (PD-CAS) were similar for pearl millet (68%) and finger millet (69%); PD-CAS for sorghum was 57%. Total dietary fiber content of the foods ranged from 7.6 to 10.1%, with the soluble dietary fiber content of the foods being about 10% higher than that of the corresponding blends. Extrusion enhanced the in vitro protein digestibility of foods, but no marked difference occurred in the in vitro carbohydrate digestibility among the unprocessed blends and the extruded foods. The net protein ratio, protein efficiency ratio, and biological values were higher for the finger millet food than for the pearl millet food, probably because of the higher lysine content of the finger millet protein.Contribution No. 95-253-J of the Kansas Agricultural Experiment Station.     

挤压加工对脱壳菜籽油脂品质的影响

研究了脱壳油菜籽挤压系统参数(套筒温度、螺杆转速、螺头至模板距离、模孔长度、模孔孔径)对从榨笼中挤压出的菜籽油的游离脂肪酸、碘值和油脂稳定性的影响规律。结果表明:挤压系统参数对脱壳菜籽油的游离脂肪酸及油脂稳定性的影响较大,对油脂碘值影响较小。比较了传统压榨菜籽油、挤压不脱壳菜籽油、挤压脱壳菜籽油的游离脂肪酸、碘值和油脂稳定性,结果显示:从榨笼挤出的脱壳菜籽油的游离脂肪酸及油脂稳定性都好于传统压榨油和不脱壳挤压油。