Thermo-Mechanical Properties Study of Stabilized Soil Bricks to Sugar Cane Molasses and Cassava Starch Binders

The current study deals Swith thermo-mechanical properties of stabilized soil small bricks with the help of organic binders of sugar cane molasses and cassava starch. Different formulations of soil concrete have been suggested after the geotechnical characterization of samples of soil was taken. From these, it arises that the studied soil is the most plastically clay (of type A3) according to GTR classification. Samples made of small bricks and measured out at 4%, 6% and 8% of binders (molasses, starch or molasses + starch) have been warmed up to different temperatures (100°C, 150°C, 200°C and 250°C) for the rising of the thermic behavior under different conditions and submitted to crushing testings for the estimation of characteristic resistances to the compression. According to the mechanical behavior, we note an improvement of resistances for small bricks measured 4%, 6% and 8%, of molasses respectively of 32.44%, 32.06% and 23.43% against the value of reference for small bricks without molasses. In the same way, the binder (molasses + starch) also reveals an improvement of resistance to the compression of 13.27%, 26.17% and 26.17%. On the contrary, the stabilization with the starch binder did not bring a significative improvement. According to the thermic influence, the heating at 100°C of stabilized small bricks at 4%, 6% and 8% of molasses, reveals a significative improvement of resistances. Moreover, the stabilization with the starch reveals on the contrary a good behavior for heatings at 150°C and 250°C. In short, for the binder (molasses + starch), it is the heating at 200°C that shows some improvements of remarkable resistances. Different analyses of realized statistics also show the effectivity of obtained results. For all realized formulations, the measuring out at 6% of binders (molasses, or molasses + starch) seems as optimal in front of the best thermo-mechanical revealed properties.

Modeling and Optimization of the Shear Strength of Cassava Starch-Based Adhesives Using Artificial Intelligence Methods

With the exponential growth of the computing power,machine learning techniques have been successully used in various applications.This paper intended to predict and optimize the shear strength of single lap cassava starch-based adhesive joints for comparison with the application of artificial intelligence(AI)methods.The shear strength was firstly determined by the experiment with three independent experimental variables(starch content,NaOH concentration and reaction temperature).The analysis of range(ANORA)and analysis of variance(ANOVA)were applied to investigate the optimal combination and the significance of each factor for the shear strength based on the orthogonal experiment.The performance of all AI models was char acterized by mean absolute error(MAE),root mean square error(RMSE)and regression coefficient(R^(2))compared with the experi-mental ones.The GA optimized ANN model was combined with the genetic algorithm(GA)to find the optimal combination of factors for the finalized optimized cassava starch adhesives(CSA-OP).The physicochemical prop-erties of the cassava starch and CSA-OP were determined by the FTIR,TGA and SEM EDS,respectively.The results showed that the numerical optimized condition of the GA optimized ANN model was superior to the orthogonal experimental optimized condition.The sensitivity analysis revealed that the relative importance of variables was consistent with the results from ANOVA.FTIR results showed that there were high hydroxyl groups in cassava starch.TGA results showed that the residue of CSA OP was higher than the assava starch.SEM EDS results showed that both the cassava starch and CSA OP had abundant carbon and oxygen functional groups.Consequently,the obtained results revealed that the use of AI methods was an adequate approach to model and optimize the experimental variables of the shear strength of single lap cassava starch-based adhesive joints.

Physicochemical Properties Comparative Analysis of Corn Starch and Cassava Starch, and Comparative Analysis as Adhesive

The morphology and properties of corn starch and cassava starch were compared by SEM, DSC and TGA. Theeffects of amylose and amylopectin content on starch properties were studied by FT-IR, XRD and XPS. The plywood was pressed with the prepared adhesive and the bonding strength of the plywood was tested to analyze thedifference among the adhesives from different plant sources and the difference after blending PAPI prepolymer.FT-IR results showed that the hydroxyl peak of cassava starch was stronger and wider. TGA showed that the residue of cassava starch was lower, but the thermal stability of cassava starch was almost the same. XPS data showedthat the oxygen content of cassava starch was slightly higher, but the carbon content was slightly lower. SEM analysis showed that corn starch granules were more irregular and sharper than cassava starch, and cassava starchgranules were more uniform, regular and round.

Decay Resistance of Particleboards Manufactured with Four Agro-Forest Residues Using Cassava Starch and Urea Formaldehyde as Adhesives

Many factors including depletion of the forest, environmental awareness, and generation of large quantities of agro-forest residues have increased the need to partially or wholly replace wood with agro-forest residue for particleboard production. This study assessed the decay resistance of particleboards produced from four agro-forest residues using cassava starch and urea formaldehyde as adhesives. Musa paradisiaca pseudostem, Theobroma cacao stem and pod, and sawdust of Ceiba pentandra were used for the study. Properties determined were: Weight loss, decay resistance rating and decay susceptibility index. These properties were evaluated after 12 weeks of exposure to Coriolopsis polyzona in accordance with ASTM D 2017-05. The results indicate that the weight loss for Musa paradisiaca pseudostem particleboard was least for both urea formaldehyde and cassava starch adhesives. Even though almost all the particleboards produced were classified as resistant or highly resistant to fungi attack, those produced with urea formaldehyde had better decay resistance properties than that of cassava starch. Furthermore, particleboards coated with synthetic polyvinyl lacquer had better resistance to fungi attack than the uncoated ones. At 5% level of significance, the agro-forest residue, adhesive and surface finish as well as their interactions had significant effects on decay resistance of the particleboards produced. It is recommended that further studies which aim at determining the effect of combination of the agro-forest residues and that of urea formaldehyde and cassava starch be conducted to determine their effects on decay properties of particleboards.

Effect of Cassava Starch and Sodium Carbonate on the Properties of Local Drilling Mud: Beneficiation to Improve the Rheological and Flow Properties of Locally Formulated Mud

Drilling mud is a key component in drilling operations and in accessing oil and gas reservoirs. Bentonite is applied as a viscosifier, fluid loss control agent, and as a weighting material in water-based drilling mud. The type of bentonite used in drilling mud formulation is sodium bentonite due to its high dispersion properties and high swelling capacity. Nigeria has a huge bentonite clay deposit resources which can be evaluated and enhanced in order to be utilized as drilling mud. However, bentonite clay from different parts of Nigeria was investigated and found to be calcium bentonite which is not suitable for drilling mud, because it has low swelling capacity and poor rheological properties. In this study, local bentonite obtained from Afuze, Edo state was used to formulate different samples of drilling mud with each treated using thermo-chemical beneficiation process with sodium carbonate and cassava starch, and then undergo characterization to identify the changes in physical properties and finally, draw comparison with API values for standard drilling mud. The results obtained from this study indicates that, the flow and rheological properties of the beneficiated drilling mud developed through thermo-chemical treatment, showed significant improvement compared to the untreated mud. Therefore, pure calcium bentonite from natural deposits in Nigeria can be modified to sodium bentonite and sufficiently used in drilling mud formulation.

Production of Corn (Zea mays) Starch and Cassava (Manihot esculenta) Starch and Their Application as Yogurt Stabilizer

The present study evaluated the stabilizing effect of starch produced from corns and cassava on the stability of cow milk yogurt. A sample of both corn and cassava starch was selected and used in the yogurt making as stabilizers. The yogurt samples have been analyzed for their WHC, syneresis and protein content. The yogurt with no added starch has found to have very low WHC and high syneresis compared to other samples. The yogurt made with the addition of corn starch as a stabilizer was highly accepted than the yogurt with cassava starch and the yogurt without starch. The findings from this study provide an alternative to add the value of local corns and cassava.

Preparation of Cassava Starch-based Superabsorbent Polymer Using a Twin-roll Mixer as Reactor

Cassava starch-based superabsorbent polymer was successfully synthesized using a new technology that based on modification of a Haake twin-roll mixer as reactor. The cassava starch was first gelatinized then modified by grafting under external shear stress in the reactor. The torque and temperature curves as a function of time can reflect the variations in the reactor and also offer some information about the copolymerization reaction. The advantages of this system include starch modification can be carried out （l） with high starch concentration, （2） under controlled ticne and （3） smaller amount of sample （60 g） required. The technology provides useful guides for reactive extrusion. The starch grafted composites were characterized by Fourier transform infrared spectroscopy （FTIR）, nuclear magnetic resonance （NMR） and thermal gravimetric analysis （TGA）. The TGA was also used for determining the percentage of grafting ratio. The results show that the cassava starch has been successfully grafted with acrylamide then crosslinked by N,N＇-methylene-bisacrylamide using this reactor. The ultimate water absorbent capacity of the cassava-based superabsorbent polymer impacted by various pH values illustrated that the acid and basic solutions inhibit the ability of imbibing water. Additionally, gel properties of the cassava-based superabsorbent polymer were investigated. It can be concluded that the structure of cassava gel is stable, while the three dimensional network of cassava-based superabsorbent polymer is rigid but its structure could not resist external force effectively and everlastingly since G＇ was decreased with increasing amplitude.

Effects of Bacterial Manure from Cassava Alcohol Fermentation Mash on Yield and Starch Content of Cassava

In order to provide a scientific basis for the utilization of cassava alcohol fermentation mash and the high-yield and high-efficiency cultivation of cassava,compound microbial inoculum was inoculated into the cassava alcohol fermentation mash to prepare bacterial manure,which was then applied to two cassava varieties,Nanzhi 199 and SC 205 to explore the optimum application amount,application method and application concentration. The results showed that when the inoculation amount of the compound microbial inoculum was 2‰ of the mass of the mash,the requirements of industrial production of liquid bacterial manure and agricultural application can be met,saving costs. After the emergence of cassava seedlings,if they were drenched with the bacterial manure of cassava alcohol fermentation mash through roots once according to the amount of 67. 5 t/ha and irrigated with the bacterial manure once every 15 d under drought conditions,both the yield and quality of cassava can be improved significantly. The yield and starch content of Nanzhi 199 reached 26 196. 23 kg/ha and 30. 32%,36. 57% and4. 75 percentage points higher than those of CK. The yield and starch content of SC 205 reached 41 126. 06 kg/ha and 23. 74%,99. 25% and3. 19 percentage points higher than those of CK. Under the application modes of foliar spray,root irrigation and foliar spray + root irrigation,the fertilization effect was more obvious. When undiluted bacterial manure of cassava alcohol fermentation mash was applied according to the amount of 52. 5 t/( ha·time),the fertilization effect of the application mode of foliar spray + root irrigation was the best. The bacterial manure from cassava alcohol fermentation mash can be directly applied without dilution,and the fertilizer efficiency will be reduced significantly after dilution.

Structural and Thermomechanical Study of Plastic Films Made from Cassava-Starch Reinforced with Kaolin and Metakaolin

The structural and thermomechanical properties of starch-based plastic films reinforced with kaolin and metakaolin have been studied by various techniques (X-ray diffraction, IR-TF spectroscopy, scanning electron microscopy, tensile tests, and thermal resistance). The results obtained showed that kaolin, an inert material, prevents the starch from losing its granular structure and to solubilize during the heating, generating plastic films of low Young’s modulus (7 MPa). On the other hand, metakaolin, an amorphous and dehydroxylated material obtained after heating of kaolin at 700°C for 1 hour, substantially improves the thermomechanical properties of the plastic films. The Young’s modulus increases from 19 MPa to 25 MPa while the thermal resistance increases from 90°C to 120°C. This was attributed to good dispersion of the metakaolin in the polymer matrix after the loss of the granular structure of the starch during heating.

4种植物源性成分多重real-time PCR检测方法的建立及其在食用淀粉中的应用

建立一种可同时快速检测红薯、木薯、马铃薯、玉米源性成分的多重实时聚合酶链式反应(real-time polymerase chain reaction,real-time PCR)方法。分别以红薯g3pdh基因、木薯g3pdh基因、马铃薯UGPase基因、玉米zSSIIb基因为靶基因设计特异性引物和TaqMan探针,以18S rRNA基因为内参基因,建立多重real-time PCR方法,开展方法学验证,并对不同掺入比例模拟样品和实际淀粉样品进行检测。结果显示,该方法具有高通量、特异性强、灵敏度高等优点。与15种非目标源性均无交叉反应;对目标DNA的检测灵敏度可达到3×10^(-3) ng/μL,且具有良好的线性关系和扩增效率;对淀粉样品的检出限可达0.1%,对50份实际样品进行检测,结果与参比方法一致,说明建立的多重real-time PCR法可用于食用淀粉种类掺假鉴别检测。

淀粉的改性及其对淀粉/PBAT/碳酸钙复合材料结构和性能的影响

采用甘油、六偏磷酸钠(SHMP)和聚乙二醇(PEG)改性木薯淀粉并制备改性淀粉/聚己二酸对苯二甲酸丁二醇酯(PBAT)/碳酸钙复合材料,采用傅里叶变换红外光谱仪(FTIR)、X射线衍射仪(XRD)、扫描电子显微镜(SEM)、差示扫描量热仪(DSC)、热失重分析仪(TG)等对改性淀粉和复合材料进行分析,研究改性淀粉对复合材料结构和性能的影响。结果表明,甘油的外增塑作用和PEG、SHMP的内增塑作用使淀粉化学结构改变、无定形成分增加,淀粉颗粒由饱满的圆球状变成了不规则的大颗粒,250℃前稳定性提高,250℃后稳定性降低,有利于使用加工和热分解,不同改性剂改性淀粉结晶熔融行为存在差异;复合不会改变PBAT、碳酸钙和淀粉的原有晶型,但相容性的差异导致复合材料热性能和力学性能的差异,改性淀粉增加了复合材料的韧性,甘油、SHMP和PEG的协同改性使淀粉与PBAT、碳酸钙的相容性最佳,复合材料的综合性能最好。

临界熔融协同冻融处理对木薯淀粉/魔芋胶复配物理化及结构特性的影响

以木薯淀粉(cassava starch,CS)和魔芋胶(konjac gum,KGM)为原材料,以“临界熔融-冻融”(critical melting and freeze-thawing,CMFT)为主要手段制备CS/KGM复配物,研究了临界熔融协同冻融处理对CS/KGM复配物理化性质及结构特性的影响。结果表明:CMFT有效促进了可溶性淀粉组分的释放,显著增加了其与KGM相互作用的位点。所制备的复配物耐热加工特性显著提升(溶解度、膨胀度显著降低),其中熔融起始温度从64.13℃(天然)增加至69.73℃(0.7%KGM,P<0.05)。CMFT还显著改善了复配物的糊化特性,其中崩解值从1246.00 mPa·s(天然)显著下降至949.12 mPa·s(0.7%KGM),而最终黏度从2182.00(天然)显著提高至2447.00 mPa·s(0.7%KGM,P<0.05)。此外,CMFT显著增加了复配物的相对结晶度(从22.19%增加到25.50%,P<0.05),表明复配物内部结构相对致密。较高浓度的KGM添加一定程度上促进了CMFT处理中CS与KGM间的协同作用。综上,该研究证明CMFT可通过部分弱化淀粉颗粒结构和释放可溶性淀粉组分增强CS/KGM协同作用,使所制备的复配物具有显著提高的耐热加工特性及糊化特性,并有望作为功能性复配材料应用到食品加工中。

木薯淀粉和改性淀粉结构特性及其与粉圆品质的关系

【目的】粉圆市场需求量日益增加,探究不同淀粉对粉圆品质的影响,明确淀粉结构特性与粉圆品质的关系,为高品质粉圆的产品开发提供理论依据。【方法】以市售的3种木薯淀粉和2种木薯改性淀粉(羟丙基二淀粉磷酸酯淀粉、醋酸酯淀粉)为原料制作粉圆,分析淀粉的粒径、直链淀粉含量、膨胀度、溶解度、热力学特性和冻融稳定性差异,以及粉圆的质构特性,并对淀粉结构特性与粉圆的质构特性进行相关性分析。【结果】不同木薯淀粉和改性淀粉的粒径、膨胀度和溶解度存在显著差异(P<0.05),改性淀粉的粒径离散度(1.17~1.27)、膨胀度(30.48%~30.91%)显著高于木薯淀粉(粒径离散度0.89~1.08、膨胀度24.60%~26.38%)。淀粉的离散度、膨胀度与粉圆的硬度、咀嚼性具有显著负相关性(P<0.05),淀粉的溶解度与粉圆的粘性具有显著正相关性(P<0.05)。5种淀粉的热力学特性与冻融稳定性同样存在显著差异(P<0.05),改性淀粉的初始凝胶温度(55.45~59.90℃)和析水率显著低于木薯淀粉的初始凝胶温度(63.80~65.00℃)和析水率。淀粉的凝胶温度、焓变和析水率与粉圆的硬度、咀嚼性具有显著正相关性(P<0.05)。【结论】不同品牌木薯淀粉的粒度分布离散度、膨胀度和冻融稳定性与粉圆的硬度和咀嚼性具有显著相关性。3种木薯淀粉中,以TPK木薯淀粉制作的粉圆品质最好;改性淀粉具有较高的膨胀度和冻融稳定性,能降低粉圆的硬度和咀嚼性,具有抗老化效果,适合用于速冻粉圆和免煮速冻粉圆加工。

野葛淀粉与木薯淀粉混粉理化特性分析

以野葛淀粉和木薯淀粉为原料,将木薯淀粉分别以10%、30%、50%和70%的质量分数掺入野葛淀粉。研究了原粉基本成分、原粉和混粉的结构、凝胶特性、抗氧化活性、热特性、冻融稳定性、消化特性、冲调特性。结果表明:随着木薯淀粉比例的增多,可以根据扫描电镜中的颗粒形状明显区别原粉及混粉,混粉平均粒径(10.68~13.05μm)均比野葛淀粉(9.47μm)高。野葛淀粉与木薯淀粉分别为C型及A型晶体结构,混粉后并未改变其结构及红外光谱图。混粉的糊化起始温度随添加量增加而显著升高(P<0.05),更难糊化。混粉抗氧化能力降低、多次冻融后趋于稳定、冲调黏度增大;混粉后硬度增大,最高达到2410.46 g,质地硬化,凝胶性能变差;混粉的抗性淀粉(质量分数0.37%~1.59%)相对野葛淀粉较低(5.65%)。木薯淀粉的掺入对混粉影响较大,有利于从淀粉的结构和理化特性等方面为鉴别野葛淀粉中是否掺有木薯淀粉提供参考。

木薯纳米淀粉的制备及乳化性能研究

以木薯淀粉为原料,采用沉淀法制备木薯纳米淀粉,探究淀粉添加量、超声波振幅、乙醇体积分数、搅拌时间对纳米淀粉粒径的影响,同时分析了木薯纳米淀粉的基本特质和乳化性能。结果表明,淀粉添加量5%(质量分数)、超声波振幅70%、乙醇体积分数60%、搅拌时间15 min时,粒径最小为75.91 nm。核磁共振氢谱、扫描电镜、透射电镜分析表明,沉淀法成功制备木薯纳米淀粉,淀粉基本化学结构不变;与原淀粉相比,用纳米淀粉为乳化剂制备的Pickering乳液粒径较小,乳化活性、乳化稳定性及贮藏稳定性均得到显著提升。该研究结果可为木薯淀粉应用提供参考依据。

不同交联度木薯羟丙基淀粉糊液性能研究

通过对7种不同交联度的木薯变性淀粉(羟丙基淀粉、羟丙基二淀粉磷酸酯)完全糊化后的糊液进行耐酸性、耐蒸煮性、抗剪切性等性能对比研究,探讨了不同交联度对木薯羟丙基淀粉糊液性能的影响。结果表明:经磷酸盐交联和羟丙基醚化共同改性处理的羟丙基二淀粉磷酸酯的抗剪切和耐酸性能优于羟丙基淀粉;就5种交联羟丙基淀粉而言,HPST3的耐盐性能较差,但其他4种淀粉在一定交联范围内,糊液耐盐性能与交联度有关,随着交联度增大其耐盐性能也随之提高,另外2种羟丙基淀粉在一定氯化钠添加量的范围内也表现出较为出色的耐盐性能;在5种羟丙基二淀粉磷酸酯中,抗剪切性能和耐酸性能随着交联度增大而下降。结合各淀粉性能可知,交联度中等的羟丙基二淀粉磷酸酯可应用于蚝油等高盐环境中及酸奶等酸性环境中;羟丙基淀粉可应用于低速搅拌及耐蒸煮的烘焙预拌粉中。