Quality and Storage Characteristics of Hot Press Tortilla Prepared from Yam-Wheat Composite Flour

Mixtures of refined wheat flour (RWF) with flours from different sources could impact the functional qualities and shelf life of wheat-based products. Storage stability is one of the most critical factors for tortilla quality. Tortillas made from yam (Dioscorea sp.) wheat composite flours were characterized. RWF was substituted with 5%, 10%, 15%, and 20% of fermented yam flour-brown (FYF) and unfermented yam flour-white (UYF). Farinograph water absorptions of UYF-composite flours (65.5% - 77.1%) were significantly (P < 0.05) higher than FYF-composite flour absorptions (60.5% - 61.5%). During storage, moisture contents of composite flour tortillas increased while the RWF-tortilla decreased. Tortilla from FYF-composite flour exhibited greater strength (3.1 N at day zero on average) compared to UYF-composite tortillas (2.1 N at day zero on average), while UYF-composite flour tortillas had good extensibility and rollability properties. The properties and composition type and ratios of flour blends affected tortilla quality during the storage period. The substitution of RWF with 15% or 20% UYF would be more suitable for making tortilla with improved properties compared to that of FYF.

Structures and Properties of Composite Yarns of Filaments and Wool Staple Fibers

More and more composite yarns of filament and wool staple fiber have been applied to develop the new type of fabrics. However, the great difference in yarn structures between the composite yarns and conventional staple yarns does affect the properties of yarns and fabrics. In this paper, it has been studied that the differences of the composite yarn properties of tensile, bending rigidity, torsional rigidity, the hairiness and irregularity etc.

Composition and Functional Properties of Yam Bean (<i>Pachyrhizus</i>spp.) Seed Flour

Yam bean (Pachyrhizus spp.) is legume crop that not only produces edible roots but also has a high yield of unutilized seeds. Although the yam bean seeds are rich in protein, they are not used due to a high content of toxic rotenone. In this study, yam bean seeds were detoxified and the nutritional and functional properties of their protein determined to assess the proteins’ potential for applications. Seeds of 10 accessions (2 accessions of P. erosus, 4 accessions of P. ahipa and 4 accessions of P. tuberosus) were analyzed for proximate composition, pasting and functional properties (bulk density, least gelation concentration, water absorption capacity, oil absorption capacity, emulsifying capacity, emulsion stability, foaming capacity, foam stability and protein solubility). The results showed that yam bean seeds contained: 29.2 - 32.1 g/100g proteins, 31.3 - 33.0 g/100 g carbohydrates, 24.1 - 25.6 g/100g total fat, 7.5 - 8.1 g/100g crude fiber and 3.4 - 4.1 g/100g ash. The defatted P. erosus seed flour contained 45.6 - 48.8 g/100g protein, 32.6 - 36.5 g/100g total carbohydrate, 6.7 - 7.1 g/100g crude fiber, 6.0 - 6.4 g/100g ash and 5.2/100 g crude fat. The defatted yam bean seed flour exhibited relatively high protein solubility (68.0% - 70.4%), least gelation concentration (14%), water absorption capacity (2.8% - 2.9%) and oil absorption capacity (1.5%). The defatted flour exhibited emulsifying capacity of 35.7% - 36.0%, emulsion stability of 33.2% - 33.5%, foaming capacities of 42% and foam stability of 25.1% - 25.8%. With respect to pasting properties, the defatted yam bean seed flours exhibited pasting temperature of 80.0?C - 81.3?C, peak viscosity of 145.5 - 146.7 RVU, trough viscosity of 95.1 - 102.0 RVU, break down of 43.5 - 51.6 RVU, set back of 252.9 - 258.1 RVU and final viscosity of 348 - 360 RVU. The results show that yam bean seed has potential for use in both food and non-food applications.

Prediction of Final Velocity of Aramid Fabric-Resin Composite Laminates Subjected to Ballistic Impact

The strain rate effects of aramid fiber material, quasi-static and ballistic impact perforation of composite laminates made of aramid fabric and phenolic resin/PVB are investigated respectively by means of MTS, split Hopkinson tension bars and ballistic impact apparatus. The tensile impact experiments on aramid fiber material are performed in strain rate range from 0.01/s to 1000/s. Experimental results show that the mechanical properties of aramid fiber material are insensitive to strain rate in the range from 0. 01/s to 1 000/s. An energy model to predict final velocity of composite laminates subjected to ballistic impact is proposed on the basis of experimental data of quasi-static perforation through the targets. The predicted final velocities show good agreement with the experimental final velocity.

云南紫山药茎叶的营养成分及开发利用前景

对云南紫山药茎叶的营养、功能成分和开发利用进行研究,结果表明,云南紫山药茎叶中除蛋白质(157 g/kg)、脂肪(9 g/kg)、碳水化合物(666 g/kg)、粗纤维(309 g/kg)、灰分(96 g/kg)和能量(14320 kJ/kg)等常规营养成分高外,还含有丰富的尿囊素(5.3 g/kg)、多酚(2.7 g/kg)、粗多糖(25.9 g/kg)、16种氨基酸、氮(25.1 g/kg)、磷(2887 mg/kg)、钾(3340 mg/kg)、钠(6.58 mg/kg)、钙(9023 mg/kg)、镁(2293 mg/kg)、锰(210 mg/kg)、锌(29.7 mg/kg)、铁(122.6 mg/kg)、硼(28.8 mg/kg)、钼(0.182 mg/kg)、β-胡萝卜素(1413μg/g)、维生素E(73.6 mg/kg)和烟酸(31.12μg/g)等成分,其地上生物量较高,在生长中可修剪下一部分茎叶和在秋季后采收利用,幼嫩的茎尖作蔬菜食用,叶片制成紫山药茶饮用,茎叶作为饲料可提高肉质和品质,对功能成分进行提取加工生产营养保健品、食品和药品,变废为宝,提高经济效益。

桑叶等复合粉剂对灵山麻鸡生长性能、消化酶活性、肠道菌群及血清免疫指标的影响

试验旨在探讨桑叶等复合粉剂对灵山麻鸡生长性能、消化酶活性、肠道菌群及血清免疫指标的影响。选取200只56日龄体重相近、健康的灵山麻鸡,随机分为4组,每组5个重复,每个重复10只鸡。对照组饲喂基础饲粮,试验1组、试验2组和试验3组分别在基础饲粮中添加2.0%、1.0%和0.5%桑叶等复合粉剂。试验期42 d。结果显示,与对照组相比,试验2组麻鸡平均日增重升高了12.65%(P<0.05),料重比显著降低(P<0.05);各试验组大肠杆菌、沙门氏菌的数量及腹泻率均显著降低(P<0.05),十二指肠胰蛋白酶、淀粉酶、脂肪酶及盲肠纤维素酶活性显著提高(P<0.05),血清免疫球蛋白G(IgG)含量分别提高了40.69%、49.88%和25.72%(P<0.05),血清总蛋白(TP)、白蛋白(ALB)和球蛋白(GLB)含量显著升高(P<0.05),白球比(A/G)显著降低(P<0.05)。研究表明,桑叶等复合粉剂能够提高灵山麻鸡生长性能、消化酶活性,降低腹泻率,改善灵山麻鸡的血清生化指标和免疫功能,桑叶等复合粉剂适宜添加量为1.0%。

Comprehensive characterization of yam tuber nutrition and medicinal quality of Dioscorea opposita and D.alata from different geographic groups in China

China is an important domestication center of yams,and two main yam species of Dioscorea opposita and D.alata are commonly cultivated in China.However,the differences of nutritional and medicinal characteristics between the two species and their subgroups remain unclear,which would greatly affect the resource conservation and commercial utilization of yams.In this study,typical yam resources including the species of D.opposita(wild and cultivated Ruichang yam from southern China,and Tiegun yam from northern China)and two landraces of D.alata(Longyan yam and Anyuan yam from southern China)were selected as materials.Nutritional traits and medicinal characteristics were determined and analyzed respectively.The results showed that there was no significant differences in the content of most nutrients between D.opposita and D.alata,but most cultivated Ruichang yam of D.opposita showed higher levels of starch,soluble sugar,sucrose,and ascorbate in tuber than that in yam from D.alata.Moreover,an UPLC-MS method was developed for identification and determination of medicinal characteristics in the two species.The results showed that allantoin can be detected in all selected samples.Cultivated Ruichang yam of D.opposita possessed the highest allantoin content among the tested materials,and was significantly different with that in Tiegun yam and D.alata.Dioscin was not detected in D.alata.Overall,there was little difference in nutritional composition between D.opposita and D.alata,but the medicinal quality of D.opposita was better than that of D.alata.Due to the outstanding comprehensive quality,the local variety of cultivated Ruichang yam can be further developed and utilized.

Effect of Incorporation of Yam Flour and Moringa Powder in Wheat Bread on Glycemic Response

This study aimed to investigate the effect of yam flour substitution (Dioscorea alata L.) and moringa powder in wheat bread on glycemic response. Glycemic index (GI) and glycemic load (GL) of pieces of bread were determined. A mixture plan design was used to determine the optimal formulation of bread made of yam flour, wheat flour and moringa powder. The mixture of 79.4% soft wheat flour, 20% yam flour and 0.6% moringa leaves powder has a good potential in bread preparation and was used in this study. 100% wheat bread was used as control. Postprandial blood glucose response (glycemic response) was evaluated with the glucose used as a reference food. Blood glucose responses were measured at different intervals for 2 hours. The results indicated that composite bread had low GI and GL values than wheat bread. Values are GI = 80 and GL = 61.2 for wheat bread and GI = 37.78 and GL = 29.65 for the composite bread. This study demonstrated that the inclusion of yam flour of moringa leaves powder in bread production might not pose a threat to blood glucose response compared to wheat bread. These pieces of bread could be included easily in diabetics’ and non-diabetics diet.

山药同根同源植物零余子的研究进展

山药是薯蓣的地下根茎,零余子长在薯蓣的叶茎之间,是山药在地上茎叶部位珠芽的总称,两者属同根同源植物。山药是传统的药食同源植物,而零余子却因商业价值低常被种植户丢弃。拟通过文献查找、整理和总结,对零余子的成分、药理活性及山药和零余子的成分对比进行综述,以期推动人们对零余子化学成分和药理活性的研究,更好地开发利用零余子。

山西省山药主产区土壤养分与重金属污染特征评价

【目的】探究山西省山药主产区土壤养分及重金属环境质量状况,为山药种植制定科学合理的施肥标准和促进山药种植区土壤环境高效管理提供参考。【方法】以山西省晋中市、临汾市、吕梁市和运城市山药主产区为研究对象,采集土壤样品并对土壤养分和重金属现状进行统计分析和评价。【结果】山西省山药主产区种植园土壤pH均值为8.6,土壤肥力整体处于低水平和极低水平,其中,有机质、全氮和碱解氮含量均值分别为7.7 g/kg、0.4 mg/kg和28.0 mg/kg,土壤养分等级以极低水平为主,占比分别为72.7%、95.5%和51.1%;有效磷为4.2 mg/kg,均处于极低水平;速效钾为93.5 mg/kg,以低水平为主,占比为54.5%。土壤有机质、全氮、碱解氮和速效钾变异系数为47.6%~72.0%,属中等程度变异;有效磷变异系数达145.1%,属高度变异。山药种植园土壤内梅罗综合污染指数(P综)均值为1.3,处于轻度污染水平,占比为63.6%。变异系数依次为Cd>Hg>As>Cu>Cr>Pb,除Pb外,其余重金属变异系数均在40%以上。土壤有机质与其他养分含量均呈显著正相关关系;Cu与Cr、Cu与Pb和As与Cr均呈显著正相关关系。【结论】山西省山药主产区种植园属碱性土壤,土壤肥力整体处于低水平和极低水平;土壤环境主要表现为Cu、Cd和Cr富集,极少数山药种植园存在Hg富集,不存在As和Pb污染。

山药营养成分研究进展

山药营养成分丰富,含有淀粉、氨基酸、多糖、薯蓣皂苷、矿物质元素等多种成分,有降血糖、抗氧化、调节胃肠道、提高免疫力等功效,具有广阔的开发利用前景和巨大的经济价值。本文概述了山药营养成分、生物活性成分及其研究进展,希望为山药的开发应用提供参考。

山药果蔬在乳酸菌发酵过程中组分及生物活性变化

通过对山药果蔬乳酸菌发酵液理化指标、微生物指标、酶活性、抗氧化性及抑菌活性的测定,研究其发酵过程中组分和生物活性的变化。结果显示:pH值和总酸含量在2~4 d变化最快,8 d后趋于稳定;总糖含量先下降、后上升、最后又下降,12 d后达到最低并趋于稳定;亚硝酸盐含量第4天最高,10 d后降至最低;前6 d是微生物主要增殖期,随着时间延长,乳酸菌逐渐成为优势菌种,并抑制其他杂菌生长;超氧化物歧化酶(superoxide dismutase,SOD)、淀粉酶、蛋白酶和脂肪酶随着时间延长,活性逐渐增强,SOD活性最高,脂肪酶活性最低;DPPH自由基、羟自由基、超氧阴离子自由基清除率和总抗氧化活性随着时间延长逐渐增强,10 d后最高且趋于稳定;对大肠杆菌和金黄色葡萄球菌的抑制率随时间延长逐渐增强,12 d后最高。本研究为果蔬乳酸菌发酵的工艺和功能研究提供了一定的理论依据。

西番莲山药复合果醋的研制

以西番莲和山药为原料,进行西番莲山药复合果醋的研制。研究结果显示西番莲汁与山药汁最优配比为1∶2;酒精发酵工艺为初始糖度20%,酵母接种量0.02%,温度20℃,发酵时间84h;醋酸发酵优化工艺为初始酒精度7%,醋酸菌接种量9%,温度32℃,发酵时间8天。成品果醋色泽呈橙黄色,具有西番莲和山药特有的香气,醋香浓郁,口感丰满,酸甜适中,澄清透亮。果醋酸度4.5g/dL,糖度13.2%,DPPH·自由基清除率97.5%。

浙江紫山药营养成分及薯蓣皂苷元含量测定

[目的]测定浙江紫山药(Purple Dioscorea batatas Decne.)的营养成分及薯蓣皂苷元含量。[方法]通过常规营养成分测定方法,分析评价浙江江山峡口镇、台州椒江的紫山药粗蛋白、粗脂肪、淀粉、微量元素、氨基酸等主要营养成分的含量,并以硫酸显色法检测紫山药药理活性成分薯蓣皂苷元含量。[结果]浙江江山峡口镇、台州椒江的紫山药粗蛋白平均含量为13.82%,粗脂肪平均含量为1.00%,粗纤维平均含量为25.13%,淀粉平均含量为15.93%,且含有丰富的K、Fe、Zn、Mg、Mn、Ca等微量元素;江山峡口镇、台州椒江的紫山药含有的17种氨基酸中,人体必需氨基酸含量高,且氨基酸组成全面,其中,主要鲜味氨基酸谷氨酸含量最高,为12.3、10.2mg/g干基,其次是天门冬氨酸,含量为10.9、9.8mg/g干基;药理活性成分薯蓣皂苷元含量平均达2.14%。[结论]浙江紫山药为高蛋白、低脂肪、高碳水化合物的绿色食品,并有一定的药理作用,具有较高的开发价值。

三组分长丝与短纤维复合纱线的生产原理

棉包涤丝包芯纱的毛羽较多,纱线的结构比较松懈,耐磨性能差,易起毛起球,为使这些问题得到有效的解决,以利于生产花色或混色纱线,通过自行设计的带有沟槽前皮辊的喂入牵伸和张力控制装置,在传统的环锭细纱机上一步纺成具有特殊结构的三组分复合纱线,并对其成纱过程与机制进行分析,提出了影响三组分复合纱线性能的工艺参数。

双轴向纬编织物热塑性单层板的拉伸性能

采用以纬平针为地组织,经纬向衬入玻璃纤维和聚丙烯纤维的双轴向纬编结构预型件,利用热压方法制备复合材料单层板,研究了双轴向纬编针织物热塑性单层板的拉伸性能以及拉伸各向异性。通过改变衬纬玻璃纤维长丝的线密度,分析了纤维体积含量对材料初始模量和断裂强度的影响关系,并对材料的断裂形式进行了分析。试验表明,双轴向纬编织物热塑性复合材料的轴向拉伸和非轴向拉伸的力学性能有较大差异,材料的轴向拉伸初始模量和断裂强度与纤维体积含量成正比,衬纱的引入提高了针织物复合材料的力学性能。

石英纤维增强氰酸酯树脂基复合材料性能研究

研究了QF210石英纤维增强新型的改性氰酸酯树脂基复合材料的耐热性、力学性能和介电性能,结果表明5528A/QF210复合材料具有优良的力学性能和优异的介电性能,可在150℃下使用。尤其是5528A/QF210复合材料的介电性能具有极好的频率稳定性,适合作为宽频高透波材料。

绢丝/锦纶长丝sirofil复合纱成纱性能

以锦纶低弹丝和绢粗纱为原料,纺制不同捻度、不同喂入间距的绢丝/锦纶长丝sirofil复合纱,测试了复合纱的强伸性能、条干不匀和毛羽。通过对实验结果进行方差分析发现,在实验范围内,复合纱成纱强度和断裂伸长率均随纺纱捻度的增加而增加,但纺纱两组分喂入间距对其影响不大;成纱捻度和两组分喂入间距对成纱的条干不匀CV值影响不显著;复合纱的毛羽指数随成纱捻度及两组分在前罗拉处喂入间距的增加均呈现下降趋势。由此得到实验范围内绢丝/锦纶长丝sirofil复合纱的优化纺纱工艺参数:捻度850捻/m,前罗拉喂入间距18 mm。

复合益生菌发酵凝固型山药香蕉酸奶的研制

以山药浆、香蕉粉和鲜牛奶为主要原料,利用保加利亚乳杆菌、嗜热链球菌和益生菌(Lactobacillus casei Zhang)按1∶1∶1混合作为复合益生菌菌种,研制出一种集山药、香蕉和益生菌于一体的兼具营养保健功能新型乳品。通过单因素和正交实验确定了复合益生菌发酵山药香蕉酸奶的最佳工艺条件。结果表明:在鲜牛奶中添加1.8%复合益生菌、15%山药浆、0.3%香蕉粉,发酵8h。在此工艺条件下制得的酸奶风味独特、质地均匀、营养丰富,而且在储藏期内,该酸奶的活菌数表现稳定,优于同类产品。

山药的研究

对山药的种类、分布、栽培、贮藏、鉴别和鉴定。