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Sample records for cassava starch films

  1. A Comparative Study of Some Properties of Cassava and Tree Cassava Starch Films

    Science.gov (United States)

    Belibi, P. C.; Daou, T. J.; Ndjaka, J. M. B.; Nsom, B.; Michelin, L.; Durand, B.

    Cassava and tree cassava starch films plasticized with glycerol were produced by casting method. Different glycerol contents (30, 35, 40 and 45 wt. % on starch dry basis) were used and the resulting films were fully characterized. Their water barrier and mechanical properties were compared. While increasing glycerol concentration, moisture content, water solubility, water vapour permeability, tensile strength, percent elongation at break and Young's modulus decreased for both cassava and tree cassava films. Tree cassava films presented better values of water vapour permeability, water solubility and percent elongation at break compared to those of cassava films, regardless of the glycerol content.

  2. Effect of carboxymethyl cellulose concentration on physical properties of biodegradable cassava starch-based films

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    Sriburi Pensiri

    2011-02-01

    Full Text Available Abstract Background Cassava starch, the economically important agricultural commodity in Thailand, can readily be cast into films. However, the cassava starch film is brittle and weak, leading to inadequate mechanical properties. The properties of starch film can be improved by adding plasticizers and blending with the other biopolymers. Results Cassava starch (5%w/v based films plasticized with glycerol (30 g/100 g starch were characterized with respect to the effect of carboxymethyl cellulose (CMC concentrations (0, 10, 20, 30 and 40%w/w total solid and relative humidity (34 and 54%RH on the mechanical properties of the films. Additionally, intermolecular interactions were determined by Fourier transform infrared spectroscopy (FT-IR, melting temperature by differential scanning calorimetry (DSC, and morphology by scanning electron microscopy (SEM. Water solubility of the films was also determined. Increasing concentration of CMC increased tensile strength, reduced elongation at break, and decreased water solubility of the blended films. FT-IR spectra indicated intermolecular interactions between cassava starch and CMC in blended films by shifting of carboxyl (C = O and OH groups. DSC thermograms and SEM micrographs confirmed homogeneity of cassava starch-CMC films. Conclusion The addition of CMC to the cassava starch films increased tensile strength and reduced elongation at break of the blended films. This was ascribed to the good interaction between cassava starch and CMC. Cassava starch-CMC composite films have the potential to replace conventional packaging, and the films developed in this work are suggested to be suitable for low moisture food and pharmaceutical products.

  3. Cassava Starch Edible Film Incorporated with Lemongrass Oil: Characteristics and Application

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    Muhammad Dani Supardan

    2016-04-01

    Full Text Available The objective of this research is to evaluate the effect of the addition of lemongrass essential oil (LGO on the characteristics and antimicrobial properties of cassava starch based films. Edible films were prepared from a mixture of cassava starch and glycerol. LGO was added to edible films as natural antimicrobial agent. There was a reduction in tensile strength of edible film because of incorporation of LGO. The presence of LGO also caused to a reduction in roughness of the edible film. The experimental results showed that Trichoderma and Penicillium was not appear upon the film until the third day of incubation. Meanwhile, the use of edible films containing LGO as antimicrobial agents caused to a reduction in microbial counts of meat during storage.

  4. Obtaining a Flexible Film Elaborated from Cassava Thermoplastic Starch and Polylactic Acid

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    Germán A. Arboleda

    2015-01-01

    Full Text Available A flexible film was obtained from a blend of cassava thermoplastic starch and polylactic acid, using maleic anhydride as coupling agent. For this, an experimental design with three factors was used: polylactic acid content, coupling agent content, and temperature profile of the blown extrusion. It was found that the three factors generated significant differences on the response variables of tensile mechanical properties individually as in their triple interaction. Differential scanning calorimetry (DSC was used by understanding the behavior of thermal properties of TPS/PLA blends with and without coupling agent, finding similar results between both. From this, the combination with 28% polylactic acid, 0.87% coupling agent, and 155.75°C temperature profile permitted the obtaining of a material with outstanding mechanical properties and offered advantages from the economic point of view.

  5. Measurement of the transmittance of edible films of aloe vera (barbadensis miller) and cassava starch using optical fibers trifurcated

    Science.gov (United States)

    Díaz, L.; Reales, J.; Torres, C.

    2017-01-01

    In Colombia, especially in the Atlantic Coast it is produced and marketed the costeño cheese, an indigenous product of the gastronomy of this region, but the prolonged exposure of this product to the environment leads to microbial contamination and non-enzymatic rancidity. For this reason the transmittance of an edible coating based in aloe vera gel and cassava starch to preserve costeño cheese was evaluated using trifurcated optical fibers. The results become a tool for the selection of treatments in making edible films and their subsequent use in coatings for various types of food products.

  6. Cassava and corn starch in maltodextrin production

    OpenAIRE

    Geovana Rocha Plácido Moore; Luciana Rodrigues do Canto; Edna Regina Amante; Valdir Soldi

    2005-01-01

    Maltodextrin was produced from cassava and corn starch by enzymatic hydrolysis with alpha-amylase. The cassava starch hydrolysis rate was higher than that of corn starches in maltodextrin production with shorter dextrose equivalent (DE). DE values do not show directly the nature of the obtained oligosaccharides. Maltodextrin produced from cassava and corn starch was analysed by high performance liquid chromatography (HPLC), and the analysis showed that maltodextrin production differs accordin...

  7. Cassava starch in the Brazilian food industry

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    Ivo Mottin Demiate

    2011-06-01

    Full Text Available Cassava starch is a valued raw material for producing many kinds of modified starches for food applications. Its physicochemical properties, as well as its availability, have made it an interesting and challenging ingredient for the food industry. In the present work, food grade modified cassava starches were purchased from producers and analyzed for selected physicochemical characteristics. Samples of sour cassava starch were included, as well as one sample of native cassava starch. Results showed that almost all modified starches were resistant to syneresis, produced pastes more stable to stirred cooking, and some of them were difficult to cook. The sour cassava starches presented high acidity and resulted in clear and unstable pastes during stirred cooking, susceptible to syneresis.

  8. Cassava and corn starch in maltodextrin production

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    Geovana Rocha Plácido Moore

    2005-08-01

    Full Text Available Maltodextrin was produced from cassava and corn starch by enzymatic hydrolysis with alpha-amylase. The cassava starch hydrolysis rate was higher than that of corn starches in maltodextrin production with shorter dextrose equivalent (DE. DE values do not show directly the nature of the obtained oligosaccharides. Maltodextrin produced from cassava and corn starch was analysed by high performance liquid chromatography (HPLC, and the analysis showed that maltodextrin production differs according to the source of the starch. This is important in defining the application of the maltodextrin, according to its desired function.

  9. Properties and antioxidant action of actives cassava starch films incorporated with green tea and palm oil extracts.

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    Kátya Karine Nery Carneiro Lins Perazzo

    Full Text Available There is an interest in the development of an antioxidant packaging fully biodegradable to increase the shelf life of food products. An active film from cassava starch bio-based, incorporated with aqueous green tea extract and oil palm colorant was developed packaging. The effects of additives on the film properties were determined by measuring mechanical, barrier and thermal properties using a response surface methodology design experiment. The bio-based films were used to pack butter (maintained for 45 days under accelerated oxidation conditions. The antioxidant action of the active films was evaluated by analyzing the peroxide index, total carotenoids, and total polyphenol. The same analysis also evaluated unpacked butter, packed in films without additives and butter packed in LDPE films, as controls. The results suggested that incorporation of the antioxidants extracts tensile strength and water vapor barrier properties (15 times lower compared to control without additives. A lower peroxide index (231.57%, which was significantly different from that of the control (p<0.05, was detected in products packed in film formulations containing average concentration of green tea extracts and high concentration of colorant. However, it was found that the high content of polyphenols in green tea extract can be acted as a pro-oxidant agent, which suggests that the use of high concentration should be avoided as additives for films. These results support the applicability of a green tea extract and oil palm carotenoics colorant in starch films totally biodegradable and the use of these materials in active packaging of the fatty products.

  10. Genetic modification of cassava enhances starch production

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ Recently, a field test of transgenic cassava (Manihot esculenta Crantz) for enhanced starch production by the Shanghai Institute of Plant Physiology & Ecology (SIPPE), the CAS Shanghai Institutes for Biological Sciences, proved successful. Through application of transgenic technologies in cassava, the starch quality of this tropical root crop was largely improved. The new cassava cultivars are believed to have a tremendous potential for industrial application in the future.

  11. Properties of baked foams from citric acid modified cassava starch and native cassava starch blends.

    Science.gov (United States)

    Pornsuksomboon, Kanlaya; Holló, Berta Barta; Szécsényi, Katalin Mészáros; Kaewtatip, Kaewta

    2016-01-20

    Starch foams from native cassava starch (NS) and citric acid modified cassava starch (CNS) were prepared using baking processes with blend ratios of 80/20, 60/40, 50/50, 40/60 and 20/80. The density, thickness, morphology, thermal stability and water absorption of the NS, CNS and blended starch foams were determined. The ratio of the two starch components had a significant influence on the density and thickness of the blended starch foams. All blended starch foams showed good water resistance. Moreover, the morphology of the blended starch foam with the NS/CNS ratio of 50/50 showed a more ordered distribution of cell sizes with thicker cell walls than for the NS and CNS foams. The thermal stability of the blended starch foams was somewhat lower than the stability of the NS foam but not to the extent that it affected any potential practical applications.

  12. Anaerobic digestion of cassava starch factory effluent.

    Science.gov (United States)

    Manilal, V B; Narayanan, C S; Balagopalan, C

    1990-06-01

    Biomethanation of cassava starch factory effluent in a batch digester produced 130 l biogas/kg dry matter with an average melthane content of 59%. About 63% COD was removed during 60 days. In semicontinuous digesters, gas production was 3251/kg dry matter with a retention time of 33,3 days giving a COD reduction of 50%. Size of starter inoculum was important for good biogasification of the effluent.

  13. Study on the Rheological Property of Cassava Starch Adhesives

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    Junjun Liu

    2014-03-01

    Full Text Available The main goal of this study was to use cassava starch in the production of environmentally sound adhesives. ‘Three-formaldehyde glue’ pollutes the environment and harms to human health strongly, which widely used for wood-based panels preparation. Environment-friendly cassava starch adhesives were prepared using method of oxidation-gelatinization, insteading of the three formaldehyde glue. The effects of the quality ratio of starch and water, temperature and shear rate on the apparent viscosity of the adhesive were studied. The rheological eigenvalue of apparent viscosity was studied through nonlinear regression. The results showed that the apparent viscosity of cassava starch adhesives decreased with the increasing of temperature; the apparent viscosity decreased slowly with the increasing of rotor speed; the phenomenon of shear thinning appeared within cassava starch adhesives which was pseudo-plastic fluids. Cassava starch adhesives with characteristics of non-toxic, no smell and pollution could be applied in interior and upscale packaging.

  14. Características físicas de filmes biodegradáveis produzidos a partir de amidos modificados de mandioca Physical characteristics of cassava modified starch films

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    Celina Maria Henrique

    2008-03-01

    , foram mais permeáveis que o PVC. Porém, quando se compara o filme biodegradável de amidos modificados com o filme comercial de PVC, ainda há muito que se trabalhar na formulação para melhorar várias propriedades deste tipo de embalagem, que tem amplo uso atualmente.Cassava starches may be used as raw materials for developing biodegradable films. Some starch modification processes can make them miscible in cold water and others can modify their film properties, making them stronger and more flexible. The aim of this study was to evaluate the physical characteristics of biodegradable films developed from cassava modified starches using the casting process (dehydration of a filmogenic solution on Petri dishes. The modified starches used were cross linked, low and high viscosity carboxymethyl starches and esterified starch. Starch viscosity is an important property to produce the filmogenic solution and it was tested using the Rapid Visco Analyser (RVA. Excepting cross linked starch, all modified starches presented cold solubility. This property enables an easier preparation of the filmogenic solutions. However, all modified starches presented a severe reduction of setback values, property associated with film formation. The cassava modified starch films were compared to commercial PVC films of 0.0208 to 0.0217 mm thickness. The cassava modified starch films presented thickness values from 0.0551 to 0.1279 mm. The minimum thickness values were observed in pre-gelatinized and cross linked films. The scanning electron microscopy analysis of the films showed differences among the starches. The resulting films were transparent and homogeneous. There was no significant interference of film thickness in water vapor permeability and the films with 5% dry matter were more permeable than the PVC film. However, when modified starch films are compared to PVC commercial films, there is still much research to be made in the formulation to improve several properties necessary to

  15. Polymorphism of starch pathway genes in cassava.

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    Vasconcelos, L M; Brito, A C; Carmo, C D; Oliveira, E J

    2016-12-02

    The distribution and frequency of single nucleotide polymorphisms (SNPs) can help to understand changes associated with characteristics of interest. We aimed to evaluate nucleotide diversity in six genes involved in starch biosynthesis in cassava using a panel of 96 unrelated accessions. The genes were sequenced, aligned, and used to obtain values for nucleotide diversity (π), segregating sites (θ), Tajima's D test, and neighbor-joining (NJ) clustering. On average, one SNP per 147 and 171 bp was identified in exon and intron regions, respectively. Thirteen heterozygous loci were found. Three of seven SNPs in the exon region resulted in non-synonymous replacement or four synonymous substitutions. However, no associations were noted between SNPs and root dry-matter content. The parameter π ranged from 0.0001 (granule bound starch synthase I) to 0.0033 (α-amylase), averaging 0.0011, while θ ranged from 0.00014 (starch branching enzyme) to 0.00584 (starch synthase I), averaging 0.002353. The θ diversity value was typically double that of the π. Results of the D test did not suggest any evidence of deviance of neutrality in these genes. Among the evaluated accession, 82/96 were clustered using the NJ method but without a clear separation of the root dry-matter content, root pulp coloration, and classification of the cyanogenic compound content. High variation in genes of the starch biosynthetic pathway can be used to identify associations with the functional properties of starch for the use of polymorphisms for selection purposes.

  16. 地膜覆盖对木薯生长发育和产量及淀粉含量的影响%Effects of Plastic Film Mulching on Development and Yield and Starch Content of Cassava

    Institute of Scientific and Technical Information of China (English)

    韦威旭; 韦民政; 覃维治; 陆柳英; 唐秀桦; 韦哲; 何虎冀; 甘秀芹; 韦本辉

    2009-01-01

    [Objective] The study was to explore cultivation techniques with less cost and high benefit for cassava.[Method] 2 planting patterns of plastic film mulching and no mulching (CK) were taken to plant cassava, the effects of plastic film mulching on growth of stem and leaf, yield components and starch content of cassava were studied.[Result] Plastic film mulching could improve the growth of stem and leaf of cassava at early and middle stage and increase the biomass of cassava.After plastic film mulching, the length and diameter of root tuber, number and weight of root tuber per plant and fresh root tuber yield per plot of cassava were increased by 17.79%, 14.61%, 14.28%, 76.14%, 76.09% resp.than that of CK.After plastic film mulching the starch content of cassava was decreased by 2% than that of CK, while the starch yield of cassava of the same area was increased by 65.35% than that of CK.[Conclusion] Plastic film mulching was the effective measurement of cultivation with less cost and high benefit for cassava, the yield increasing effect was realized through promoting stem and leaf growth of cassava at early and middle sate, improving root tuber diameter and root tuber weight per plant, and increasing the plumpness of root tuber.%[目的]探索木薯节本增效栽培技术.[方法]分别采用地膜覆盖与不覆膜(对照)2种方式种植木薯,研究地膜覆盖对木薯茎叶生长、产量构成因素及淀粉含量的影响.[结果]地膜覆盖可促进木薯前中期茎叶生长,增加木薯生物量;地膜和覆盖后,木薯的块根长度、块根直径、单株块根数、单株块根重和小区鲜块根产量分别较对照增加了17.79%、14.61%、14.28%、76.14%和76.09%;地膜覆盖后木薯的淀粉含量较对照降低2%,但相同面积木薯的淀粉产量较对照增加65.35%.[结论]地膜覆盖是木薯节本增效栽培的有效措施,其增产效应主要是通过促进木薯前中期茎叶生长、提高块根直径和

  17. Electrical and absorption properties of fresh cassava tubers and cassava starch

    Science.gov (United States)

    Harnsoongnoen, S.; Siritaratiwat, A.

    2015-09-01

    The objective of this study was to analyze the electrical and absorption properties of fresh cassava tubers and cassava starch at various frequencies using electric impedance spectroscopy and near-infrared spectroscopy, as well as determine the classification of the electrical parameters of both materials using the principle component analysis (PCA) method. All samples were measured at room temperature. The electrical and absorption parameters consisted of dielectric constant, dissipation factor, parallel capacitance, resistance, reactance, impedance and absorbance. It was found that the electrical and absorption properties of fresh cassava tubers and cassava starch were a function of frequency, and there were significant differences between the materials. The dielectric constant, parallel capacitance, resistance and impedance of fresh cassava tubers and cassava starch had similar dramatic decreases with increasing frequency. However, the reactance of both materials increased with an increasing frequency. The electrical parameters of both materials could be classified into two groups. Moreover, the dissipation factor and phase of impedance were the parameters that could be used in the separation of both materials. According to the absorbance patterns of the fresh cassava tubers and cassava starch, there were significant differences.

  18. High pressure intensification of cassava resistant starch (RS3) yields

    OpenAIRE

    2015-01-01

    Cassava starch, typically, has resistant starch type 3 (RS3) content of 2.4%. This paper shows that the RS3 yields can be substantially enhanced by debranching cassava starch using pullulanase followed by high pressure or cyclic high-pressure annealing. RS3 yield of 41.3% was obtained when annealing was carried out at 400 MPa/60°C for 15 min, whereas it took nearly 8 h to obtain the same yield under conventional atmospheric annealing at 60°C. The yield of RS3 could be further significantly in...

  19. Characters related to higher starch accumulation in cassava storage roots.

    Science.gov (United States)

    Li, You-Zhi; Zhao, Jian-Yu; Wu, San-Min; Fan, Xian-Wei; Luo, Xing-Lu; Chen, Bao-Shan

    2016-01-01

    Cassava (Manihot esculenta) is valued mainly for high content starch in its roots. Our understanding of mechanisms promoting high starch accumulation in the roots is, however, still very limited. Two field-grown cassava cultivars, Huanan 124(H124) with low root starch and Fuxuan 01(F01) with high root starch, were characterised comparatively at four main growth stages. Changes in key sugars in the leaves, stems and roots seemed not to be strongly associated with the final amount of starch accumulated in the roots. However, when compared with H124, F01 exhibited a more compact arrangement of xylem vascular bundles in the leaf axils, much less callose around the phloem sieve plates in the stems, higher starch synthesis-related enzymatic activity but lower amylase activity in the roots, more significantly up-regulated expression of related genes, and a much higher stem flow rate (SFR). In conclusion, higher starch accumulation in the roots results from the concurrent effects of powerful stem transport capacity highlighted by higher SFR, high starch synthesis but low starch degradation in the roots, and high expression of sugar transporter genes in the stems. A model of high starch accumulation in cassava roots was therefore proposed and discussed.

  20. Biodegradable foam trays obtained from mixtures of non-irradiated and irradiated cassava starches

    Energy Technology Data Exchange (ETDEWEB)

    Brant, A.J.C.; Naime, N.; Lugao, A.B.; Ponce, P., E-mail: thonybrant@gmail.com, E-mail: patiponce@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Biodegradable polymers, such as starch, cellulose, PHB, PLA, and derivatives thereof, are being studied to produce innovative packaging in the most diverse shapes (films, bags, trays, bottles, etc.) to attend this current market trend. The aim of this work was to produce foam trays from cassava starch for food packaging by extrusion-thermopressing process. Their formulations were based on non-irradiated and γ-irradiated starches at diverse radiation absorbed doses (kGy) in order to evaluate the influence of the irradiated starches on the physical properties of the trays. Water absorption results showed an irregular increase with the increase of the absorbed dose: 26.32% and 39.84% for the trays based on starch 0 kGy and 1:1 (w/w) mixture of starches 0 kGy and 100.0 kGy, respectively. Other physicochemical properties were evaluated from the starches utilized and the trays obtained. (author)

  1. Organic acid profile of commercial sour cassava starch

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    DEMIATE I.M.

    1999-01-01

    Full Text Available Organic acids are present in sour cassava starch ("polvilho azedo" and contribute with organoleptic and physical characteristics like aroma, flavor and the exclusive baking property, that differentiate this product from the native cassava starch. Samples of commercial sour cassava starch collected in South and Southeast Brazil were prepared for high performance liquid chromatography (HPLC analysis. The HPLC equipment had a Biorad Aminex HPX-87H column for organic acid analysis and a refractometric detector. Analysis was carried out with 0.005M sulfuric acid as mobile phase, 0.6ml/min flow rate and column temperature of 60° C. The acids quantified were lactic (0.036 to 0.813 g/100g, acetic (0 to 0.068 g/100g, propionic (0 to 0.013 g/100g and butyric (0 to 0.057 g/100g, that are produced during the natural fermentation of cassava starch. Results showed large variation among samples, even within the same region. Some samples exhibited high acid levels, mainly lactic acid, but in these neither propionic nor butyric acids were detected. Absence of butyric acid was not expected because this is an important component of the sour cassava starch aroma, and the lack of this acid may suggest that such samples were produced without the natural fermentation step.

  2. Biogas Production From Cassava Starch Effluent Using Microalgae As Biostabilisator

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    B. Budiyono

    2011-07-01

    Full Text Available The rapid growing of Indonesian population is emerging several critical national issues i.e. energy, food, environmental, water, transportation, as well as law and human right. As an agricultural country, Indonesia has abundant of biomass wastes such as agricultural wastes include the cassava starch wastes. The problem is that the effluent from cassava starch factories is released directly into the river before properly treatment. It has been a great source of pollution and has caused environmental problems to the nearby rural population. The possible alternative to solve the problem is by converting waste to energy biogas in the biodigester. The main problem of the biogas production of cassava starch effluent is acid forming-bacteria quickly produced acid resulting significantly in declining pH below the neutral pH and diminishing growth of methane bacteria. Hence, the only one of the method to cover this problem is by adding microalgae as biostabilisator of pH. Microalgae can also be used as purifier agent to absorb CO2.The general objective of this research project was to develop an integrated process of biogas production and purification from cassava starch effluent by using biostabilisator agent microalgae. This study has been focused on the used of urea, ruminant, yeast, microalgae, the treatment of gelled and ungelled feed for biogas production, pH control during biogas production using buffer Na2CO3, and feeding management in the semi-continuous process of biogas production. The result can be concluded as follows: i The biogas production increased after cassava starch effluent and yeast was added, ii Biogas production with microalgae and cassava starch effluent, yeast, ruminant bacteria, and urea were 726.43 ml/g total solid, iii Biogas production without  microalgae was 189 ml/g total solid.

  3. Performance Evaluation of Local Cassava Starches with Imported Starch for Drilling Fluid

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    Harry, T.F.

    2016-10-01

    Full Text Available Local cassava starches and an imported starch were characterized and evaluated for their performance as drilling fluid additives. Two local cassava cultivars, TMS 98/0581 and TMS 96/1632, starches and an imported starch were characterized by using X-ray diffraction techniques. Bentonite mud beneficiated with the starches were subjected to API viscosity and filtration tests. The local and imported starches were classified as B type crystal structure. The starches average particle sizes were 51.63nm, 23.57nm and 57.94nm for TMS 98/0581, TMS 96/1632 and imported starches respectively. The crystalline indices were between 22 and 35, while average specific surface areas were 151.65, 361.28 and 142.04 m2 /g for TMS 98/0581, TMS 96/1632 and imported starches respectively. The morphology indices, ranges were from 0.5 to 0.7485. The structural properties of TMS 98/0581 starch were found to be significantly close to that of the imported starch and were observed to be closer in performance as drilling fluid additive than TMS 96/1632. Local cassava starches with structural properties as TMS 98/0581, could serve as good substitute for drilling operation. The viscosity and fluid loss control results of the local samples compared favourably with the imported one.

  4. Morphological and mechanical characterization of thermoplastic starch and its blends with polylactic acid using cassava starch and bagasse

    Science.gov (United States)

    This study aims the use of an agro waste coming from the industrialization of cassava starch, known as cassava bagasse (BG). This material contains residual starch and cellulose fibers which can be used to obtain thermoplastic starch (TPS) and /or blends reinforced with fibers. In this context, it w...

  5. Starch films from a novel (Pachyrhizus ahipa) and conventional sources: Development and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, Olivia V., E-mail: ovlopez75@yahoo.com.ar; Garcia, Maria A.

    2012-10-01

    Biodegradable films from ahipa, cassava and corn native starches were developed by casting method and their physicochemical, mechanical and barrier properties were analyzed taking into account the different starch botanical sources. Filmogenic suspensions were prepared; their rheological behaviors were studied and all of them exhibited film-forming ability. However, mechanical assays demonstrated that unplasticized films were too rigid, limiting their technological applications. Thus, 1.5% w/w of glycerol as plasticizer was added to filmogenic suspensions and film flexibility and extensibility were improved, this effect was more significant for ahipa and cassava starch films. Furthermore, thickness, moisture content and water solubility of the developed films were increased when plasticizer was incorporated. Glycerol addition reduced film water vapor permeability and the lowest reduction corresponded to cassava starch films due to the high viscosity of its filmogenic suspensions. Plasticized starch films resulted to be UV radiation barriers; ahipa starch films had the lowest light absorption capacity and higher transparency than cassava and corn starch films. Dynamic-mechanical analysis indicated that plasticized films were partially miscible systems exhibiting two relaxations, one attributed to the starch-rich phase and the other to the glycerol-rich one. Likewise, it could be demonstrated that glycerol exerted a major plasticizing effect on ahipa starch matrixes. Highlights: Black-Right-Pointing-Pointer Ahipa, cassava and corn starch films were developed by casting method. Black-Right-Pointing-Pointer Glycerol effect on film mechanical behavior was major for tuberous starch films. Black-Right-Pointing-Pointer Ahipa starch films resulted to be more transparent with lower UV absorption capacity. Black-Right-Pointing-Pointer Plasticized films were partially miscible systems: with a glycerol-rich and a starch-rich phase. Black-Right-Pointing-Pointer Glycerol exerted

  6. Cassava starch effluent treatment with concomitant SCP production.

    Science.gov (United States)

    Manilal, V B; Narayanan, C S; Balagopalan, C

    1991-03-01

    Yeasts and yeast-like organisms were chosen for the aerobic treatment of cassava starch factory effluent. A mixed culture of Candida utills and Endomycopsis fibuliger efficiently and rapidly utilized both starch and free sugars. After 28 h fermentation the protein content of the biomass was 22% (w/w), which remained unchanged during the remainder of the fermentation (60 h). This treatment removed 94% of the COD and 91% of the BOD.

  7. Improved cassava starch by antisense inhibition of granule-bound starch synthase I

    NARCIS (Netherlands)

    Raemakers, C.J.J.M.; Schreuder, M.M.; Suurs, L.C.J.M.; Furrer-Verhorst, M.; Vincken, J.P.; Vetten, de N.; Jacobsen, E.; Visser, R.G.F.

    2005-01-01

    Cassava is a poor man's crop which is mainly grown as a subsistence crop in many developing countries. Its commercial use was first as animal feed (also known as tapioca), but has shifted since the late sixties to a source of native starch. The availability of native starches, which on the one hand

  8. Physicochemical properties of cassava starch oxidized by sodium hypochlorite.

    Science.gov (United States)

    Garrido, Lúcia Helena; Schnitzler, Egon; Zortéa, Manoela Estefânea Boff; de Souza Rocha, Thaís; Demiate, Ivo Mottin

    2014-10-01

    In this work, cassava starch was modified by treatment with sodium hypochlorite (NaClO) at different concentrations (0.8, 2.0 and 5.0 % of active chlorine) and selected physicochemical properties of the oxidized starches were investigated. The native and modified samples were evaluated considering moisture, carboxyl content, apparent viscosity, susceptibility to syneresis, mid-infrared spectroscopy and crystallinity index. The treatment with NaClO resulted in alterations in carboxyl content of the oxidized starches that increased with increasing concentration of the oxidant. Oxidized starches also showed higher susceptibility to syneresis, as assessed by the release of liquid during freezing and thawing. Apparent viscosity analysis showed decrease in peak viscosity of the oxidized starches. X-ray diffractograms showed that the oxidation influenced the extent of cassava starch relative crystallinity found to lie between 34.4 % (native) and 39.9 % (2.0 % active chlorine). The infrared spectra are sensitive to structural changes on starch macromolecules and presented characteristic peaks as C-O-C of the six carbon glucose ring absorbs at 1,150-1,085 cm(-1) and due to axial deformation these bands changed with the crystal structure of the starch samples.

  9. High pressure intensification of cassava resistant starch (RS3) yields.

    Science.gov (United States)

    Lertwanawatana, Proyphon; Frazier, Richard A; Niranjan, Keshavan

    2015-08-15

    Cassava starch, typically, has resistant starch type 3 (RS3) content of 2.4%. This paper shows that the RS3 yields can be substantially enhanced by debranching cassava starch using pullulanase followed by high pressure or cyclic high-pressure annealing. RS3 yield of 41.3% was obtained when annealing was carried out at 400MPa/60°C for 15 min, whereas it took nearly 8h to obtain the same yield under conventional atmospheric annealing at 60°C. The yield of RS3 could be further significantly increased by annealing under 400 MPa/60°C pressure for 15 min followed by resting at atmospheric pressure for 3h 45 min, and repeating this cycle for up to six times. Microstructural surface analysis of the product under a scanning electron microscope showed an increasingly rigid density of the crystalline structure formed, confirming higher RS3 content.

  10. Characterization of cassava starch processed in an internal mixer

    Directory of Open Access Journals (Sweden)

    Marcia Cristina da Silva

    2013-01-01

    Full Text Available An internal mixer connected to a torque rheometer was used to investigate the effect of moisture content (13.2 to 46.8 g.100g- 1, rotation speed (13.2 to 46.8 rpm and processing temperature (53.2 to 86.8 °C, applying a factorial central composite design, on the specific mechanical energy (SME, pasting viscosity and crystallinity of cassava starch. Torque values were highly significant for the three variables, showing decrease with increasing moisture, temperature and rpm. The highest cold viscosity (CV was obtained at 13.18 g.100g- 1 moisture, 86.87 °C and 30 rpm due to increased rupture of starch granules caused by processing at lower moisture condition. Peak viscosity (PV values were higher than CV values which indicated that the processing was not able to destroy completely the molecular integrity of the starch granules. Smaller setback (SB at high temperature and rpm and low moisture showed possible starch depolymerization causing loss of recrystallization capacity. Processing under low moisture content resulted in reduction of crystallinity. The results showed that the effect of moisture was more pronounced than rotation speed and processing temperature of cassava starch.

  11. Preparation and the properties of the composite films from cassava starch and guar gum%木薯淀粉-瓜尔胶复合膜的制备及性质研究

    Institute of Scientific and Technical Information of China (English)

    贾英

    2012-01-01

    The raw guar gum,anionic guar gum with cassava starch were blended to make composite basic edible film in the certain proportion.The films with different contents of starch and guar gum were respectively prepared and characterized.Their properties were measured.The film containing cassave starch and guar gum with the ratio of 80∶20 exhibited the good elongation(E).Compared with the pure starch film,tensile strength(TE)increased by 50%,E decreased by 30%,and the water vapor permeability decreased to 15.8%,water absorption changed a little.The film containing cassave starch and anionic guar gum with the ratio of 80∶20 had the good E.Compared with cassava starch film,the E increased by 142%,but the TE decreased by 22%.The water vapor permeability decreased by 5.4%,while the water absorption decreased by 5.5%.%研究木薯淀粉与瓜尔胶、木薯淀粉与阴离子瓜尔胶的复合膜,淀粉含量为复合基质量的100%、80%、60%、40%和20%制成复合膜,对膜的性质用红外、热重以及扫描电镜分别表征,对膜的力学性能、水蒸气透过率和吸水性能测试。分别以强度和伸长率为指标得出最优的复合膜配比。以强度为指标的最优复合膜成分:淀粉为80%,瓜尔胶为20%,得到样本1-2与原淀粉膜相比强度提高50%,伸长率下降30%,水蒸气透过率下降15.8%,吸水率几乎没有变化。以伸长率为指标的最优膜成分:淀粉80%,阴离子瓜尔胶20%,得到样本2-1与原木薯淀粉膜相比伸长率提高了142%,但强度降低了22%,水蒸气透过率下降了5.4%,吸水性降低了5.5%。成膜条件为:淀粉糊化温度为95℃,反应时间0.5 h,烘干温度为50℃。

  12. Pepino japonês (Cucumis sativus L. submetido ao tratamento com fécula de mandioca Japonese cucumber (Cucumis sativus L. submitted of the treatment with cassava starch film

    Directory of Open Access Journals (Sweden)

    Kelen Cristina dos Reis

    2006-06-01

    Full Text Available Com o presente trabalho objetivou-se avaliar a qualidade e a vida útil do pepino (Cucumis sativus L., utilizando recobrimento com película de fécula de mandioca. Após seleção, amostras de pepino japonês foram mergulhadas em suspensões de fécula de mandioca a 0, 2, 3 e 4%, secos ao ar e armazenados em câmara fria a 5ºC e 95% de UR por 8 dias. As análises realizadas foram perda de massa, pH, sólidos solúveis (SS , acidez titulável (AT, Cor L*a*b e firmeza. O delineamento utilizado foi o DIC com 3 repetições, com os tratamentos dispostos em esquema fatorial 4 x 5. O valor encontrado para firmeza nas amostras tratadas com película a 4% foram menores em comparação aos outros tratamentos, isto, provavelmente se deve à plasticidade do tecido que estas amostras apresentaram. A película reduziu significativamente a perda de massa das amostras mantidas sob refrigeração. A aplicação de película de fécula de mandioca na concentração mais elevada (4%, proporcionou ao pepino um aspecto melhor de conservação, tornando o produto mais atraente.This work was made to evaluate the properties and postharvest life of cucumber (Cucumis sativus L. coated with cassava starch film. After the selection the fruits were dipped in suspensions 0, 2, 3 and 4% starch, dried naturally and stored in chamber cold (5ºC ± 1ºC and 90% ± 5% HR during 8 days and the analyses were done in the time zero and in intervals of 2 days. The analyses done were loss mass, titratable acidity (TA, pH, soluble solids (SS, color L*a*b and firmness. The test was conducted in completely randomized design, with three repetitions, with the treatments disposed in factory layout 4x5. The value found for firmness in the samples treated with biofilm at 4% was smaller in comparison to the other treatments, this, is probably due to the plasticity of the tissue that these samples presented. The film reduced the loss of mass of the samples maintained under refrigeration

  13. Effects of citric acid esterification on digestibility, structural and physicochemical properties of cassava starch.

    Science.gov (United States)

    Mei, Ji-Qiang; Zhou, Da-Nian; Jin, Zheng-Yu; Xu, Xue-Ming; Chen, Han-Qing

    2015-11-15

    In this study, citric acid was used to react with cassava starch in order to compare the digestibility, structural and physicochemical properties of citrate starch samples. The results indicated that citric acid esterification treatment significantly increased the content of resistant starch (RS) in starch samples. The swelling power and solubility of citrate starch samples were lower than those of native starch. Compared with native starch, a new peak at 1724 cm(-1) was appeared in all citrate starch samples, and crystalline peaks of all starch citrates became much smaller or even disappeared. Differential scanning calorimetry results indicated that the endothermic peak of citrate starches gradually shrank or even disappeared. Moreover, the citrate starch gels exhibited better freeze-thaw stability. These results suggested that citric acid esterification induced structural changes in cassava starch significantly affected its digestibility and it could be a potential method for the preparation of RS with thermal stability.

  14. Molecular evolution and functional divergence of soluble starch synthase genes in cassava (manihot esculenta crantz).

    Science.gov (United States)

    Yang, Zefeng; Wang, Yifan; Xu, Shuhui; Xu, Chenwu; Yan, Changjie

    2013-01-01

    Soluble starch synthases (SSs) are major enzymes involved in starch biosynthesis in plants. Cassava starch has many remarkable characteristics, which should be influenced by the evolution of SS genes in this starchy root crop. In this work, we performed a comprehensive phylogenetic and evolutionary analysis of the soluble starch synthases in cassava. Genome-wide identification showed that there are 9 genes encoding soluble starch synthases in cassava. All of the soluble starch synthases encoded by these genes contain both Glyco_transf_5 and Glycos_transf_1 domains, and a correlation analysis showed evidence of coevolution between these 2 domains in cassava SS genes. The SS genes in land plants can be divided into 6 subfamilies that were formed before the origin of seed plants, and species-specific expansion has contributed to the evolution of this family in cassava. A functional divergence analysis for this family provided statistical evidence for shifted evolutionary rates between the subfamilies of land plant soluble starch synthases. Although the main selective pressure acting on land plant SS genes was purifying selection, our results also revealed that point mutation with positive selection contributed to the evolution of 2 SS genes in cassava. The remarkable cassava starch characteristics might be the result of both the duplication and adaptive selection of SS genes.

  15. Chemical composition, functional and pasting properties of cassava starch and soy protein concentrate blends.

    Science.gov (United States)

    Chinma, Chiemela Enyinnaya; Ariahu, Charles Chukwuma; Abu, Joseph Oneh

    2013-12-01

    The chemical, functional and pasting properties of cassava starch and soy protein concentrate blends intended for biofilm processing were studied. Cassava starch and soy protein concentrates were prepared and mixed at different proportions (100: 0%; 90 : 10%; 80 : 20%; 70 : 30%; 60;40% and 50: 50%). Addition of varying levels of soy protein concentrates to cassava starch led to increases in moisture (from 7.10 to 9.17%), protein ( from 0.32 to 79.03%), ash (from 0.45 to 2.67%) and fat (from 0.17 to 0.98%) contents while crude fiber, carbohydrate and amylose contents decreased from ( 1.19 to 0.38%, 90.77 to 57.01% and 29.45 to 23.04%) respectively . Water absorption capacity and swelling power of cassava starch were improved as a result of soy protein concentrate addition while syneresis and solubility value of composite blends were lower than 100% cassava starch. In general, cassava-soy protein concentrate blends formed firmer gels than cassava starch alone. There were significant (p ≤ 0.05) increases in peak viscosity (from 160.12 to 268.32RVU), final viscosity (from 140.41 to 211.08RVU) and pasting temperature (from 71.00 to 72.32 °C ) of cassava starch due to addition of soy protein concentrate. These results suggest that the addition of soy protein concentrate to cassava starch affected the studied functional properties of cassava starch as evidenced by changes such as reduced syneresis, and solubility that are desirable when considering this biopolymer as an edible biofilm.

  16. Biogas Production Using Anaerobic Biodigester from Cassava Starch Effluent

    Directory of Open Access Journals (Sweden)

    S. Sunarso

    2010-12-01

    Full Text Available IKMs’ factory activity in Margoyoso produces liquid and solid wastes. The possible alternative was to use the liquid effluent as biogas raw material. This study focuses on the used of urea, ruminant, yeast, microalgae, the treatment of gelled and ungelled feed for biogas production, pH control during biogas production using buffer Na2CO3, and feeding management in the semi-continuous process of biogas production that perform at ambient temperature for 30 days. Ruminant bacteria, yeast, urea, and microalgae was added 10% (v/v, 0.08% (w/v, 0.04% (w/v, 50% (v/v of mixing solution volume, respectively. The pH of slurry was adjusted with range 6.8-7.2 and was measured daily and corrected when necessary with Na2CO3. The total biogas production was measured daily by the water displacement technique. Biogas production from the ungelling and gelling mixture of cassava starch effluent, yeast, ruminant bacteria, and urea were 726.43 ml/g total solid and 198 ml/g total solid. Biogas production from ungelling mixture without yeast was 58.6 ml/g total solid. Biogas production from ungelling mixture added by microalgae without yeast was 58.72 ml/g total solid and that with yeast was 189 ml/g total solid. Biogas production from ungelling mixture of cassava starch effluent, yeast, ruminant bacteria, and urea in semi-continuous process was 581.15 ml/g total solid. Adding of microalgae as nitrogen source did not give significant effect to biogas production. But adding of yeast as substrate activator was very helpful to accelerate biogas production. The biogas production increased after cassava starch effluent and yeast was added. Requirement of sodium carbonate (Na2CO3 to increase alkalinity or buffering capacity of fermenting solution depends on pH-value

  17. Study of cassava starch enzymatic modification for maltodextrins obtention

    Directory of Open Access Journals (Sweden)

    Miguel Angel Díaz

    2012-05-01

    Full Text Available It was pretended to investigate the effect of the most relevant variables in cassava starch enzymatic hydrolysis process, on laboratory scale, to determine appropriate industrial conditions for the obtention of different kinds of maltodextrins. An a-Amylase enzyme, from genetically modified strain of Bacillus lichenijormis, was used to hydrolize the starch. Once the variables were chosen, an experimental fractioned factorial design was established with two levels. The Dextrose Equivalent (DE was taken as the response variable. The variables studied were: temperature (80-90°C, pH (5.5-6.5, dry-weight starch concentration (30-40% w/w, enzyme dosage (0.583-0.833 ul/g starch and calcium concentration (50-70 mgIL of CaClJ Some assays were settle in order to define the rheologic behavior and to determine the most relevant variables that affect the functional properties of the maltodextrin suspensions. Both, temperature and enzyme concentration were the variables that affect the most the initial convertion rate and the characteristics of the product convertion. For the interval of time considered, the highest DE obtained was 30 and the highest initial rate was 21.7 DE/hour. The functional properties of the maltodextrin solutions were affected by temperature and dry-weight starch concentration.

  18. Kinetics of cassava starch hydrolysis with Termamyl(R) enzyme.

    Science.gov (United States)

    Paolucci-Jeanjean, D; Belleville, M P; Zakhia, N; Rios, G M

    2000-04-05

    Kinetic properties of Termamyl(R) 120L were investigated with respect to starch hydrolysis in a batch reactor at substrate concentrations of 50-270 g. dm(-3) and enzyme concentrations of 0. 17-1 cm(3). dm(-3) (i.e., cm(3) of Novo Nordisk enzymatic solution per dm(3) of raw cassava starch suspension). A general kinetic expression giving product concentration as a function of time was first developed; an equation relating the reaction rate of each product to the sum of the concentrations of oligosaccharides with a higher degree of polymerisation was then derived. The empirical model satisfactorily fits experimental data for oligosaccharides with a degree of polymerization ranging from 1 to 7.

  19. Molecular and supra-molecular structure of waxy starches developed from cassava (Manihot esculenta Crantz).

    Science.gov (United States)

    Rolland-Sabaté, Agnès; Sanchez, Teresa; Buléon, Alain; Colonna, Paul; Ceballos, Hernan; Zhao, Shan-Shan; Zhang, Peng; Dufour, Dominique

    2013-02-15

    The aim of this work was to characterize the amylopectin of low amylose content cassava starches obtained from transgenesis comparatively with a natural waxy cassava starch (WXN) discovered recently in CIAT (International Center for Tropical Agriculture). Macromolecular features, starch granule morphology, crystallinity and thermal properties of these starches were determined. M¯(w) of amylopectin from the transgenic varieties are lower than WXN. Branched and debranched chain distributions analyses revealed slight differences in the branching degree and structure of these amylopectins, principally on DP 6-9 and DP>37. For the first time, a deep structural characterization of a series of transgenic lines of waxy cassava was carried out and the link between structural features and the mutated gene expression approached. The transgenesis allows to silenced partially or totally the GBSSI, without changing deeply the starch granule ultrastructure and allows to produce clones with similar amylopectin as parental cassava clone.

  20. Chemical composition, functional and pasting properties of cassava starch and soy protein concentrate blends

    OpenAIRE

    2011-01-01

    The chemical, functional and pasting properties of cassava starch and soy protein concentrate blends intended for biofilm processing were studied. Cassava starch and soy protein concentrates were prepared and mixed at different proportions (100: 0%; 90 : 10%; 80 : 20%; 70 : 30%; 60;40% and 50: 50%). Addition of varying levels of soy protein concentrates to cassava starch led to increases in moisture (from 7.10 to 9.17%), protein ( from 0.32 to 79.03%), ash (from 0.45 to 2.67%) and fat (from 0...

  1. Rheological behavior of gamma-irradiated cassava (Manihot esculenta crantz) starch

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Orelio L.; Uehara, Vanessa B.; Mastro, Nelida L. del, E-mail: nlmastro@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    Cassava starch is the by-product of the process of pressing water out of cassava to make cassava meal. The juice has a fine starch, similar to rice or potato starch that, when dried, yields polvilho doce (sweet manioc starch); from the fermented juice comes polvilho azedo (sour manioc starch). Cassava starch can perform most of the functions where maize, rice and wheat starch are currently used. The aim of the present work was to determine the influence or ionizing radiation on the rheological behavior of aqueous preparations of gamma-irradiated cassava starch at different concentrations. Samples of polvilho doce and polvilho azedo were obtained at the local market and irradiated in plastic bags in a Gammacell 220 with doses of 1, 3 e 5 kGy, dose rate ∼ 1.2 kGy h-1. A Brooksfield viscometer was employed for the viscosity measurements. The results showed a strong dependence of the viscosity with the concentration of the starch solutions. In most of the cases there was a decrease of viscosity with the increase of the radiation dose usually seen in irradiated polysaccharides. Nevertheless, the dose response relation of the two kind of starch was different. (author)

  2. An efficient treatment for detoxification process of cassava starch by plant cell wall-degrading enzymes.

    Science.gov (United States)

    Sornyotha, Somphit; Kyu, Khin Lay; Ratanakhanokchai, Khanok

    2010-01-01

    The objective of this work was to remove linamarin in starch from cassava (Manihot esculenta Crantz cv. KU-50) roots, a high-cyanogen variety by using plant cell wall-degrading enzymes, xylanase and cellulase. The combination of xylanase from Bacillus firmus K-1 and xylanase and cellulase from Paenibacillus curdlanolyticus B-6 at the ratio of 1:9 showed the maximum synergism at 1.8 times for hydrolyzing cassava cortex cell walls and releasing linamarase. Combined enzyme treatment enhanced linamarin liberation from the parenchyma by 90%. In addition, when the combined enzymes were applied for detoxification during cassava starch production, a low-cyanide-product was obtained with decreased linamarin concentration (96%) compared to non-enzyme treated tissues. Based on these results, xylanase and cellulase treatment is a good method for low-cyanide-cassava starch production and could be applied for detoxification of cassava products during processing.

  3. Robust and biodegradable polymer of cassava starch and modified natural rubber.

    Science.gov (United States)

    Riyajan, Sa-Ad

    2015-12-10

    The application of starch based materials for packaging purposes has attracted significant interest because they are both cheap and renewable resources. The study investigated the preparation and properties of a novel biopolymer sheet produced from a blend of maleated epoxidized natural rubber (MENR) and natural rubber-g-cassava starch (NR-g-CSt). The water resistance, toluene resistance and elongation at break of the polymer blend were enhanced after the addition of the MENR compared to pristine NR-g-CSt. The maximum tensile strength and thermal stability of the NR-g-CSt/MENR blend were found in the 100:50 NR-g-CSt:MENR blend. The novel films demonstrated good biodegradability in soil.

  4. Effect of cassava starch-based edible coating incorporated with lemongrass essential oil on the quality of papaya MJ9

    Science.gov (United States)

    Praseptiangga, D.; Utami, R.; Khasanah, L. U.; Evirananda, I. P.; Kawiji

    2017-02-01

    Edible films and coatings have emerged as an alternative packaging in food applications and have received much attention due to their advantages. The incorporation of essential oils in film matrices to give antimicrobial properties had been observed recently, and could be used as promising preservation technology. In this study, cassava starch-based edible coating incorporated with lemongrass essential oil (1%) was applied by spraying and dipping methods to preserve papaya MJ9 during storage at room temperature. The quality of papaya MJ9 was analyzed based on its physicochemical and microbiological properties. The addition of lemongrass essential oil (1%) significantly inhibited the microbial growth on papaya MJ9 by reducing the value of total yeast and mold as compared to the control. This study also showed that for parameters of weight loss, total soluble solid, vitamin C, and total titratable acid, papaya MJ9 with cassava starch-based edible coating incorporated with lemongrass essential oil (1%) had the lower values than control, however, they had the higher value than control on firmness parameter. These results indicate that cassava starch-based edible coating incorporated with lemongrass essential oil (1%) can be used as an alternative preservation for papaya MJ9.

  5. Synthesis of an air-working trilayer artificial muscle using a conductive cassava starch biofilm (manihot esculenta, cranz) and polypyrrole (PPy)

    Science.gov (United States)

    Núñez D, Y. E.; Arrieta A, Á. A.; Segura B, J. A.; Bertel H, S. D.

    2016-02-01

    In this study, a methodology for obtaining a conductive cassava starch biofilm doped with lithium perchlorate (LiClO4) is shown, as well as the electrochemical technique for the synthesis of polypyrrole films, which are used for developing the trilayer artificial muscle PPy/Biopolymer/PPy designed to operate in air. Furthermore, results from the trilayer movement using chronoamperometric techniques are shown.

  6. Effect of waxy rice flour and cassava starch on freeze-thaw stability of rice starch gels.

    Science.gov (United States)

    Charoenrein, Sanguansri; Preechathammawong, Nutsuda

    2012-10-01

    Repeatedly frozen and thawed rice starch gel affects quality. This study investigated how incorporating waxy rice flour (WF) and cassava starch (CS) in rice starch gel affects factors used to measure quality. When rice starch gels containing 0-2% WF and CS were subjected to 5 freeze-thaw cycles, both WF and CS reduced the syneresis in first few cycles. However CS was more effective in reducing syneresis than WF. The different composite arrangement of rice starch with WF or CS caused different mechanisms associated with the rice starch gel retardation of retrogradation, reduced the spongy structure and lowered syneresis. Both swollen granules of rice starch and CS caused an increase in the hardness of the unfrozen and freeze-thawed starch gel while highly swollen WF granules caused softer gels. These results suggested that WF and CS were effective in preserving quality in frozen rice starch based products.

  7. Physicochemical properties of potato and cassava starches and their mutants in relation to their structural properties

    NARCIS (Netherlands)

    Gomand, S.V.; Lamberts, L.; Visser, R.G.F.; Delcour, J.A.

    2010-01-01

    Physicochemical properties [swelling power (SP), pasting behaviour and retrogradation] of five wild type (wt), five amylose free (amf), four high-amylose (ha) potato starches (ps) and one wt and amf cassava starch (cs) were investigated. While swelling of wtps occurred in two phases, amfps showed a

  8. Thermal characterization of partially hydrolyzed cassava (Manihot esculenta starch granules

    Directory of Open Access Journals (Sweden)

    Luiz Gustavo Lacerda

    2008-12-01

    Full Text Available Cassava starch, partially hydrolyzed by fungal á-amylase, was characterized using thermal analysis, light microscopy and X-ray diffraction. Thermal degradation was initiated at lower degradation temperatures after enzymatic treatment and the DSC (Differential scanning calorimetry analysis showed almost similar range of gelatinization temperature, but the enthalpies of gelatinization were quite increased for the partially hydrolyzed starch granules. The results suggested that the partial degradation of the starch granules was concentrated in the amorphous regions.Amilases fúngicas são comumente empregadas a amidos com o intuito de otimizar o rendimento de leveduras, modificar a textura de produtos panificados e prolongar a vida de prateleira do produto final. A hidrólise parcial enzimática pode auxiliar no entendimento da estrutura do amido ganular. Amido de mandioca parcialmente hidrolisado por á-amilase fúngica foi investigado utilizando-se técnicas termoanalíticas, microscopia ótica e difratometria por raios X. A degradação térmica iniciou-se a temperaturas menores após o tratamento enzimático e a análise por DSC mostrou uma próxima faixa de temperatura de gelatinização, porém, a entalpia necessária para o evento foi maior para os grânulos parcialmente hidrolisados. Os resultados sugerem que a degradação parcial do amido granular foi concentrada em regiões amorfas.

  9. DEVELOPMENT OF ADHESIVE TO THE BASIS OF CORN AND CASSAVA STARCH

    Directory of Open Access Journals (Sweden)

    Rosane Furtado Fabrício

    2014-05-01

    Full Text Available Corn and native cassava starch were modified by oxidation and acid hydrolysis, aiming to develop paper and paperboard stickers. The oxidation was made with Sodium hypochlorite (NaOCl in two distinct concentrations of active chloride which is present on oxidizing agent solution. The synthesis resulting products were used to make stickers and they were compared to corn and cassava starch based stickers without any modification, as well as commercial stickers based on polyvinyl acetate (PVA. Two different methodologies were tested using acid hydrolysis to modify corn and cassava starch, both using phosphoric acid (H3PO4 in order to obtain dextrin and subsequently use it in the production of stickers and also comparing them to petrochemical-based commercial stickers. Considering the different starch modifications methods (oxidation and acid hydrolysis, stickers based on renewable raw material were obtained, which combine biodegradability, low costs and availability.

  10. Development of waxy cassava with different Biological and physico-chemical characteristics of starches for industrial applications.

    Science.gov (United States)

    Zhao, Shan-Shan; Dufour, Dominique; Sánchez, Teresa; Ceballos, Hernan; Zhang, Peng

    2011-08-01

    The quality of cassava starch, an important trait in cassava breeding programs, determines its applications in various industries. For example, development of waxy (having a low level of amylose) cassava is in demand. Amylose is synthesized by granule-bound starch synthase I (GBSSI) in plants, and therefore, down-regulation of GBSSI expression in cassava might lead to reduced amylose content. We produced 63 transgenic cassava plant lines that express hair-pin dsRNAs homologous to the cassava GBSSI conserved region under the control of the vascular-specific promoter p54/1.0 from cassava (p54/1.0::GBSSI-RNAi) or cauliflower mosaic virus (CaMV) 35S (35S::GBSSI-RNAi). After the screening storage roots and starch granules from field-grown plants with iodine staining, the waxy phenotype was discovered: p54/1.0::GBSSI-RNAi line A8 and 35S::GBSSI-RNAi lines B9, B10, and B23. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that there was no detectable GBSSI protein in the starch granules of plants with the waxy phenotype. Further, the amylose content of transgenic starches was significantly reduced (starch granules from the wild-type (about 25%). The inner structure of the waxy starch granules differed from that of the untransformed ones, as revealed by transmission electron microscopy analysis as well as morphological changes in the iodine-starch complex. Endothermic enthalpy was reduced in waxy cassava starches, according to differential scanning calorimeter analysis. Except B9, all waxy starches displayed the A-type X-ray diffraction pattern. Amylogram patterns of the waxy cassava starches were analyzed using a rapid viscosity analyzer and found to have increased values for clarity, peak viscosity, gel breakdown, and swelling index. Setback, consistency, and solubility were notably reduced. Therefore, waxy cassava with novel starch in its storage roots was produced using the biotechnological approach, promoting its industrial utilization.

  11. Post-harvest conservation of organic strawberries coated with cassava starch and chitosan

    Directory of Open Access Journals (Sweden)

    Raquel P Campos

    2011-10-01

    Full Text Available The strawberry is as non-climacteric fruit, but has a high post-harvest respiration rate, which leads to a rapid deterioration at room temperature. This study aimed to evaluate the application of biodegradable coating on postharvest conservation of organic strawberries, cv. Camarosa, packed in plastic hinged boxes and stored at 10ºC. The treatments consisted of: a control; b 2% cassava starch; c 1% chitosan; and d 2% cassava starch + 1% chitosan. Physical and chemical characteristics of fruits were evaluated at 3, 6 and 9 days of storage, and microbiological and sensory analyses were carried out at the end of the storage period. The treatments influenced positively the post-harvest quality of organic strawberries. The coating cassava starch + chitosan provided the best results, with less than 6% of loss in fruit mass, lower counts of yeast and psychrophilic microorganisms and the best appearance according to the sensory analysis.

  12. Thin layer drying of cassava starch using continuous vibrated fluidized bed dryer

    Science.gov (United States)

    Suherman, Trisnaningtyas, Rona

    2015-12-01

    This paper present the experimental work and thin layer modelling of cassava starch drying in continuous vibrated fluidized bed dryer. The experimental data was used to validate nine thin layer models of drying curve. Cassava starch with 0.21 initial moisture content was dried in different air drying temperature (50°C, 55°C, 60°C, 65°C, 70°C), different weir height in bed (0 and 1 cm), and different solid feed flow (10 and 30 gr.minute-1). The result showed air dryer temperature has a significant effect on drying curve, while the weir height and solid flow rate are slightly. Based on value of R2, χ2, and RMSE, Page Model is the most accurate simulation for thin layer drying model of cassava starch.

  13. Process optimization for bioethanol production from cassava starch using novel eco-friendly enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Shanavas, S.; Padmaja, G.; Moorthy, S.N.; Sajeev, M.S.; Sheriff, J.T. [Division of Crop Utilization, Central Tuber Crops Research Institute, Thiruvananthapuram, 695 017 Kerala (India)

    2011-02-15

    Although cassava (Manihot esculenta Crantz) is a potential bioethanol crop, high operational costs resulted in a negative energy balance in the earlier processes. The present study aimed at optimizing the bioethanol production from cassava starch using new enzymes like Spezyme {sup registered} Xtra and Stargen trademark 001. The liquefying enzyme Spezyme was optimally active at 90 C and pH 5.5 on a 10% (w/v) starch slurry at levels of 20.0 mg (280 Amylase Activity Units) for 30 min. Stargen levels of 100 mg (45.6 Granular Starch Hydrolyzing Units) were sufficient to almost completely hydrolyze 10% (w/v) starch at room temperature (30 {+-} 1 C). Ethanol yield and fermentation efficiency were very high (533 g/kg and 94.0% respectively) in the Stargen + yeast process with 10% (w/v) starch for 48 h. Raising Spezyme and Stargen levels to 560 AAU and 91.2 GSHU respectively for a two step loading [initial 20% (w/v) followed by 20% starch after Spezyme thinning]/initial higher loading of starch (40% w/v) resulted in poor fermentation efficiency. Upscaling experiments using 1.0 kg starch showed that Stargen to starch ratio of 1:100 (w/w) could yield around 558 g ethanol/kg starch, with a high fermentation efficiency of 98.4%. The study showed that Spezyme level beyond 20.0 mg for a 10% (w/v) starch slurry was not critical for optimizing bioethanol yield from cassava starch, although an initial thinning of starch for 30 min by Spezyme facilitated rapid saccharification-fermentation by Stargen + yeast system. The specific advantage of the new process was that the reaction could be completed within 48.5 h at 30 {+-} 1 C. (author)

  14. Effect of fructooligosaccharides on the physicochemical properties of sour cassava starch and baking quality of gluten-free cheese bread

    OpenAIRE

    Rodriguez-Sandoval, Eduardo; Landi Franco, Celia M. [UNESP; Manjarres-Pinzon, Katherine

    2014-01-01

    The present research was undertaken to explore the influence of fructooligosaccharides (FOS) on the functional and thermal properties of sour cassava starch and the quality characteristics of gluten-free (GF) cheese bread. Fructooligosaccharides were used to replace sour cassava starch at substitution level of 9% (SF1), 17% (SF2), and 29% (SF3). The functional and thermal properties of the starch-FOS mixtures were determined by the water absorption index (WAI), water solubility index (WSI), p...

  15. Ozone oxidation of cassava starch in aqueous solution at different pH.

    Science.gov (United States)

    Klein, Bruna; Vanier, Nathan Levien; Moomand, Khalid; Pinto, Vânia Zanella; Colussi, Rosana; da Rosa Zavareze, Elessandra; Dias, Alvaro Renato Guerra

    2014-07-15

    Ozone is a more powerful oxidant than common oxidising agents, such as sodium hypochlorite and hydrogen peroxide. It is considered as a safer starch modification method for both consumers and the environment. However, few studies have investigated the changes in starch properties associated with ozone treatment, particularly when applied in aqueous solution. This work aimed to evaluate the carbonyl and carboxyl contents, the X-ray diffraction patterns, the spectrum profiles of Fourier transform infrared spectroscopy, the pasting properties and the surface morphology of ozone-oxidised cassava starch during 60 min under different pH (3.5, 6.5 and 9.5) at 25°C. The pH 6.5 and 9.5 seemed to favour the cross-linking between the depolymerised starch molecules during ozonation. The pH 3.5 was more effective in reducing the peak viscosity, breakdown, setback and final viscosity of cassava starch during ozonation in aqueous solution. No differences in the granule surface morphology were observed in the ozone-treated cassava starches compared to native starch.

  16. Ninety-Day Oral Toxicity Assessment of an Alternative Biopolymer for Controlled Release Drug Delivery Systems Obtained from Cassava Starch Acetate

    Directory of Open Access Journals (Sweden)

    Douglas Rossi Jesus

    2015-01-01

    Full Text Available The large consumption of biodegradable films from cassava starch acetate (FCSA as ingredients in food and pharmaceutical products requires the assessment of the possible toxicity of these products. The aim of this study was to investigate the toxicity of biodegradable film from cassava starch acetate after oral exposure of Wistar rats for 90 days. The amount of food consumed and the body weight were weekly monitored. Blood and urine samples were obtained for the assessment of serum parameters and renal function. Histopathological analyses in target organs were also performed. No evidence of clinical toxicity in hematological, biochemical, or renal parameters in the FCSA-treated animals was found. In addition, relative organ weight and histopathological evaluations did not differ between groups treated with FCSA and control. Data obtained suggest that the subchronic exposure to FCSA does not cause obvious signs of toxicity in Wistar rats, indicating possible safety of this biofilm.

  17. Ninety-Day Oral Toxicity Assessment of an Alternative Biopolymer for Controlled Release Drug Delivery Systems Obtained from Cassava Starch Acetate

    Science.gov (United States)

    Jesus, Douglas Rossi; Barbosa, Lorena Neris; Prando, Thiago Bruno Lima; Martins, Leonardo Franco; Gasparotto, Francielli; Guedes, Karla Moraes Rocha; Dragunski, Douglas Cardoso; Lourenço, Emerson Luiz Botelho; Dalsenter, Paulo Roberto; Gasparotto Junior, Arquimedes

    2015-01-01

    The large consumption of biodegradable films from cassava starch acetate (FCSA) as ingredients in food and pharmaceutical products requires the assessment of the possible toxicity of these products. The aim of this study was to investigate the toxicity of biodegradable film from cassava starch acetate after oral exposure of Wistar rats for 90 days. The amount of food consumed and the body weight were weekly monitored. Blood and urine samples were obtained for the assessment of serum parameters and renal function. Histopathological analyses in target organs were also performed. No evidence of clinical toxicity in hematological, biochemical, or renal parameters in the FCSA-treated animals was found. In addition, relative organ weight and histopathological evaluations did not differ between groups treated with FCSA and control. Data obtained suggest that the subchronic exposure to FCSA does not cause obvious signs of toxicity in Wistar rats, indicating possible safety of this biofilm. PMID:26451154

  18. Exploratory studies on the carboxymethylation of cassava starch in water-miscible organic media

    NARCIS (Netherlands)

    Yao, J; Chen, WR; Manurung, RM; Ganzeveld, KJ; Heeres, HJ; Manurung, Robbert M.; Chen, Wen-ren

    2004-01-01

    The carboxymethylation of cassava starch using sodium monochloroacetate (SMCA) as an etherification agent was investigated. Mixtures of water and water-miscible organic liquids were selected as carboxymethylation reaction medium to obtain a high degree of substitution (DS) without changing the granu

  19. Preparation and physico-chemical properties of hydrogels from carboxymethyl cassava starch crosslinked with citric acid

    Science.gov (United States)

    Boonkham, Sasikan; Sangseethong, Kunruedee; Chatakanon, Pathama; Niamnuy, Chalida; Nakasaki, Kiyohiko; Sriroth, Klanarong

    2014-06-01

    Recently, environmentally friendly hydrogels prepared from renewable bio-based resources have drawn significant attention from both industrial and academic sectors. In this study, chemically crosslinked hydrogels have been developed from cassava starch which is a bio-based polymer using a non-toxic citric acid as a crosslinking agent. Cassava starch was first modified by carboxymethylation to improve its water absorbency property. The carboxymethyl cassava starch (CMCS) obtained was then crosslinked with citric acid at different concentrations and reaction times. The gel fraction of hydrogels increased progressively with increasing citric acid concentration. Free swelling capacity of hydrogels in de-ionized water, saline solution and buffers at various pHs as well as absorption under load were investigated. The results revealed that swelling behavior and mechanical characteristic of hydrogels depended on the citric acid concentration used in reaction. Increasing citric acid concentration resulted in hydrogels with stronger network but lower swelling and absorption capacity. The cassava starch hydrogels developed were sensitive to ionic strength and pH of surrounding medium, showing much reduced swelling capacity in saline salt solution and acidic buffers.

  20. THE GENOTYPES X ENVIRONMENT INTERACTION FOR STARCH YIELD IN NINE-MONTH OLD CASSAVA PROMISING CLONES

    Directory of Open Access Journals (Sweden)

    Sholihin Sholihin

    2016-10-01

    Full Text Available Cassava (Manihot esculenta is planted in dry areas with different environmental conditions, therefore the yield is varied. The aim of the study was to analyze the genotype x environment interaction for starch yield in 9-month old cassava promising clones. The experiment was conducted on mineral soils in four different locations, i.e. Lumajang-East Java (Inceptisols, Kediri-East Java (Entisols, Pati-Central Java (Alfisols, and Tulangbawang-Lampung (Ultisols during 2004- 2005. The experiment was arranged in split plot design with three replications. The main plots were cultivation techniques, i.e. simple technology and improved technology, whereas the subplots were 15 cassava promising clones. Starch yield of 9- month old cassava plants was analysed using the additive maineffects and multiplicative interaction (AMMI. The results showed that environmental factors determined the stability of starch yield were soil bulk density on subsoil, the number of rainy days at fifth month, minimum air temperature at fourth month, and minimum air humidity at seventh month. CMM97002-183, Adira 4, CMM97007-145, CMM97007-235, Malang 2, CMM97002-36, and CMM97006-44 were identified as the stable cassava clones for starch yield in 9-month old. Average starch yield of Adira 4 was the third after MLG 10311 and CMM 97006-52. The CMM97006-52 was adapted to the soils having high P2O5 content on topsoil, high minimum air temperature at 4 and 5 months after planting, high minimum relative humidity at 7 months after planting, low total rainfall at 5 months after planting, and low number of rainy days at 5 and 8 months after planting. MLG 10311 was adapted to low soil bulk density. The average starch yield of MLG 10311 was the highest at 9 months after planting. The study implies that advanced trials for CMM 977006-52 and MLG 10311 clones are needed, so the clones can be released as new varieties of cassava. In selection and evaluation, the bulk density on subsoil is needed

  1. Production of raw cassava starch-degrading enzyme by Penicillium and its use in conversion of raw cassava flour to ethanol.

    Science.gov (United States)

    Lin, Hai-Juan; Xian, Liang; Zhang, Qiu-Jiang; Luo, Xue-Mei; Xu, Qiang-Sheng; Yang, Qi; Duan, Cheng-Jie; Liu, Jun-Liang; Tang, Ji-Liang; Feng, Jia-Xun

    2011-06-01

    A newly isolated strain Penicillium sp. GXU20 produced a raw starch-degrading enzyme which showed optimum activity towards raw cassava starch at pH 4.5 and 50 °C. Maximum raw cassava starch-degrading enzyme (RCSDE) activity of 20 U/ml was achieved when GXU20 was cultivated under optimized conditions using wheat bran (3.0% w/v) and soybean meal (2.5% w/v) as carbon and nitrogen sources at pH 5.0 and 28 °C. This represented about a sixfold increment as compared with the activity obtained under basal conditions. Starch hydrolysis degree of 95% of raw cassava flour (150 g/l) was achieved after 72 h of digestion by crude RCSDE (30 U/g flour). Ethanol yield reached 53.3 g/l with fermentation efficiency of 92% after 48 h of simultaneous saccharification and fermentation of raw cassava flour at 150 g/l using the RCSDE (30 U/g flour), carried out at pH 4.0 and 40 °C. This strain and its RCSDE have potential applications in processing of raw cassava starch to ethanol.

  2. Synergistic amylomaltase and branching enzyme catalysis to suppress cassava starch digestibility.

    Science.gov (United States)

    Sorndech, Waraporn; Meier, Sebastian; Jansson, Anita M; Sagnelli, Domenico; Hindsgaul, Ole; Tongta, Sunanta; Blennow, Andreas

    2015-11-05

    Starch provides our main dietary caloric intake and over-consumption of starch-containing foods results in escalating life-style disease including diabetes. By increasing the content of α-1,6 branch points in starch, digestibility by human amylolytic enzymes is expected to be retarded. Aiming at generating a soluble and slowly digestible starch by increasing the content and changing the relative positioning of the branch points in the starch molecules, we treated cassava starch with amylomaltase (AM) and branching enzyme (BE). We performed a detailed molecular analysis of the products including amylopectin chain length distribution, content of α-1,6 glucosidic linkages, absolute molecular weight distribution and digestibility. Step-by-step enzyme catalysis was the most efficient treatment, and it generated branch structures even more extreme than those of glycogen. All AM- and BE-treated samples showed increased resistance to degradation by porcine pancreatic α-amylase and glucoamylase as compared to cassava starch. The amylolytic products showed chain lengths and branching patterns similar to the products obtained from glycogen. Our data demonstrate that combinatorial enzyme catalysis provides a strategy to generate potential novel soluble α-glucan ingredients with low dietary digestibility assets.

  3. Improving hydrogen production from cassava starch by combination of dark and photo fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Su, Huibo; Cheng, Jun; Zhou, Junhu; Song, Wenlu; Cen, Kefa [State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027 (China)

    2009-02-15

    The combination of dark and photo fermentation was studied with cassava starch as the substrate to increase the hydrogen yield and alleviate the environmental pollution. The different raw cassava starch concentrations of 10-25 g/l give different hydrogen yields in the dark fermentation inoculated with the mixed hydrogen-producing bacteria derived from the preheated activated sludge. The maximum hydrogen yield (HY) of 240.4 ml H{sub 2}/g starch is obtained at the starch concentration of 10 g/l and the maximum hydrogen production rate (HPR) of 84.4 ml H{sub 2}/l/h is obtained at the starch concentration of 25 g/l. When the cassava starch, which is gelatinized by heating or hydrolyzed with {alpha}-amylase and glucoamylase, is used as the substrate to produce hydrogen, the maximum HY respectively increases to 258.5 and 276.1 ml H{sub 2}/g starch, and the maximum HPR respectively increases to 172 and 262.4 ml H{sub 2}/l/h. Meanwhile, the lag time ({lambda}) for hydrogen production decreases from 11 h to 8 h and 5 h respectively, and the fermentation duration decreases from 75-110 h to 44-68 h. The metabolite byproducts in the dark fermentation, which are mainly acetate and butyrate, are reused as the substrates in the photo fermentation inoculated with the Rhodopseudomonas palustris bacteria. The maximum HY and HPR are respectively 131.9 ml H{sub 2}/g starch and 16.4 ml H{sub 2}/l/h in the photo fermentation, and the highest utilization ratios of acetate and butyrate are respectively 89.3% and 98.5%. The maximum HY dramatically increases from 240.4 ml H{sub 2}/g starch only in the dark fermentation to 402.3 ml H{sub 2}/g starch in the combined dark and photo fermentation, while the energy conversion efficiency increases from 17.5-18.6% to 26.4-27.1% if only the heat value of cassava starch is considered as the input energy. When the input light energy in the photo fermentation is also taken into account, the whole energy conversion efficiency is 4.46-6.04%. (author)

  4. SACCHARIFICATION OF NATIVE CASSAVA STARCH AT HIGH DRY SOLIDS IN AN ENZYMATIC MEMBRANE REACTOR

    Directory of Open Access Journals (Sweden)

    I Nyoman Widiasa

    2012-02-01

    Full Text Available This study is aimed to develop a novel process scheme for hydrolysis of native cassava starch at high dry solids using an enzymatic membrane reactor (EMR. Firstly, liquefied cassava starch having solids content up to 50% by weight was prepared by three stage liquefactions in a conventional equipment using a commercially available heat stable a-amylase (Termamyl 120L. The liquefied cassava starch was further saccharified in an EMR using glucoamylase (AMG E. By using the developed process scheme, a highly clear hydrolysate with dextrose equivalent (DE approximately 97 could be produced, provided the increase of solution viscosity during the liquefaction was precisely controlled. The excessive space time could result in reduction in conversion degree of starch. Moreover, a residence time distribution study confirmed that the EMR could be modelled as a simple continuous stirred tank reactor (CSTR. Using Lineweaver-Burk analysis, the apparent Michaelis-Menten constant (Km and glucose production rate constant (k2 were 552 (g/l and 4.04 (min-1, respectively. Application of simple CSTR model with those kinetic parameters was quietly appropriate to predict the reactor’s performance at low space time.

  5. Some Nutritional Characteristics of Enzymatically Resistant Maltodextrin from Cassava (Manihot esculenta Crantz) Starch.

    Science.gov (United States)

    Toraya-Avilés, Rocío; Segura-Campos, Maira; Chel-Guerrero, Luis; Betancur-Ancona, David

    2017-01-19

    Cassava (Manihot esculenta Crantz) native starch was treated with pyroconversion and enzymatic hydrolysis to produce a pyrodextrin and an enzyme-resistant maltodextrin. Some nutritional characteristics were quantified for both compounds. Pyroconversion was done using a 160:1 (p/v) starch:HCl ratio, 90 °C temperature and 3 h reaction time. The resulting pyrodextrin contained 46.21% indigestible starch and 78.86% dietary fiber. Thermostable α-amylase (0.01%) was used to hydrolyze the pyrodextrin at 95 °C for 5 min. The resulting resistant maltodextrin contained 24.45% dextrose equivalents, 56.06% indigestible starch and 86.62% dietary fiber. Compared to the cassava native starch, the pyrodextrin exhibited 56% solubility at room temperature and the resistant maltodextrin 100%. The glycemic index value for the resistant maltodextrin was 59% in healthy persons. Its high indigestible starch and dietary fiber contents, as well as its complete solubility, make the resistant maltodextrin a promising ingredient for raising dietary fiber content in a wide range of foods, especially in drinks, dairy products, creams and soups.

  6. Comparison of pasting and gel stabilities of waxy and normal starches from potato, maize, and rice with those of a novel waxy cassava starch under thermal, chemical, and mechanical stress.

    Science.gov (United States)

    Sánchez, Teresa; Dufour, Dominique; Moreno, Isabel Ximena; Ceballos, Hernán

    2010-04-28

    Functional properties of normal and waxy starches from maize, rice, potato, and cassava as well as the modified waxy maize starch COLFLO 67 were compared. The main objective of this study is to position the recently discovered spontaneous mutation for amylose-free cassava starch in relation to the other starches with well-known characteristics. Paste clarity, wavelength of maximum absorption (lambda(max)), pasting properties, swelling power, solubility, and dispersed volume fraction measurements and gel stability (acid and alkaline resistance, shear, refrigeration, and freeze/thaw stability) were evaluated in the different types and sources of starch included in this study. lambda(max) in the waxy cassava starch was reduced considerably in comparison with that of normal cassava starch (535 vs 592 nm). RVA peak viscosity of waxy cassava starch was larger than in normal cassava starch (1119 vs 937 cP) and assumed a position intermediate between the waxy potato and maize starches. Acid, alkaline, and shear stability of waxy cassava starch were similar to normal cassava except for alkaline pH, at which it showed a low effect. Gels from normal root and tuber starches after refrigeration and freeze/thaw had lower syneresis than cereal starches. Gels from waxy starches (except for potato) did not present any syneresis after 5 weeks of storage at 4 degrees C. Waxy cassava starch was the only one not showing any syneresis after 5 weeks of storage at -20 degrees C. Natural waxy cassava starch is, therefore, a promising ingredient to formulate refrigerated or frozen food.

  7. Gel characteristics and microstructure of fish myofibrillar protein/cassava starch composites.

    Science.gov (United States)

    Fan, Mingcong; Hu, Ting; Zhao, Siming; Xiong, Shanbai; Xie, Jing; Huang, Qilin

    2017-03-01

    The changes in fish myofibrillar protein/cassava starch composites in the starch fraction range from 0 to 1, with their total content maintained at 60mg/mL, were investigated in terms of textural properties, rheological behaviours, morphology, spatial distribution and protein molecular structure. The results revealed that the starch fraction of 0.5 was a critical point for the conversion of the protein matrix to starch matrix and conversion of the gel from elastic to weak. Moreover, the protein-starch synergistic effect on the storage modulus was strongest at fractions of 0.5 and 0.6, due to the formation of a semi-interpenetrating network, with more amylose from the melted starch granules interpenetrated with the protein molecules, and the absorption of water by the starch granules to concentrate the protein matrix. Additionally, no covalent interaction between the protein and starch occurred with increasing starch fraction, thus having no significant influence on the protein secondary structure.

  8. Poly(Lactic Acid Filled with Cassava Starch-g-Soybean Oil Maleate

    Directory of Open Access Journals (Sweden)

    Nopparut Kiangkitiwan

    2013-01-01

    Full Text Available Poly(lactic acid, PLA, is a biodegradable polymer, but its applications are limited by its high cost and relatively poorer properties when compared to petroleum-based plastics. The addition of starch powder into PLA is one of the most promising efforts because starch is an abundant and cheap biopolymer. However, the challenge is the major problem associated with poor interfacial adhesion between the hydrophilic starch granules and the hydrophobic PLA, leading to poorer mechanical properties. In this paper, soybean oil maleate (SOMA was synthesized by grafting soybean oil with various weight percents of maleic anhydride (MA using dicumyl peroxide (DCP as an initiator. Then, SOMA was employed for the surface modifying of cassava starch powder, resulting in SOMA-g-STARCH. The obtained SOMA-g-STARCH was mixed with PLA in various weight ratios using twin-screw extruder, resulting in PLA/SOMA-g-STARCH. Finally, the obtained PLA/SOMA-g-STARCH composites were prepared by a compression molding machines. The compatibility, thermal properties, morphology properties, and mechanical properties were characterized and evaluated. The results showed that the compatibility, surface appearance, and mechanical properties at 90 : 10 and 80 : 20 ratios of PLA/SOMA-g-STARCH were the best.

  9. Deep Assessment of Genomic Diversity in Cassava for Herbicide Tolerance and Starch Biosynthesis.

    Science.gov (United States)

    Duitama, Jorge; Kafuri, Lina; Tello, Daniel; Leiva, Ana María; Hofinger, Bernhard; Datta, Sneha; Lentini, Zaida; Aranzales, Ericson; Till, Bradley; Ceballos, Hernán

    2017-01-01

    Cassava is one of the most important food security crops in tropical countries, and a competitive resource for the starch, food, feed and ethanol industries. However, genomics research in this crop is much less developed compared to other economically important crops such as rice or maize. The International Center for Tropical Agriculture (CIAT) maintains the largest cassava germplasm collection in the world. Unfortunately, the genetic potential of this diversity for breeding programs remains underexploited due to the difficulties in phenotypic screening and lack of deep genomic information about the different accessions. A chromosome-level assembly of the cassava reference genome was released this year and only a handful of studies have been made, mainly to find quantitative trait loci (QTL) on breeding populations with limited variability. This work presents the results of pooled targeted resequencing of more than 1500 cassava accessions from the CIAT germplasm collection to obtain a dataset of more than 2000 variants within genes related to starch functional properties and herbicide tolerance. Results of twelve bioinformatic pipelines for variant detection in pooled samples were compared to ensure the quality of the variant calling process. Predictions of functional impact were performed using two separate methods to prioritize interesting variation for genotyping and cultivar selection. Targeted resequencing, either by pooled samples or by similar approaches such as Ecotilling or capture, emerges as a cost effective alternative to whole genome sequencing to identify interesting alleles of genes related to relevant traits within large germplasm collections.

  10. Polymeric flocculant based on cassava starch grafted polydiallyldimethylammonium chloride: Flocculation behavior and mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Razali, M.A.A.; Ariffin, A., E-mail: srazlan@usm.my

    2015-10-01

    Graphical abstract: - Highlights: • Flocculation performance of cassava grafted polyDADMAC was studied. • Turbidity and TSS removal increased with increasing grafting percentage. • The grafted polymer showed good removal in acidic and neutral region. • Zeta potential results pointed to the charge neutralization mechanism. • Flocs increased with increasing grafting percentage and molecular weight. - Abstract: In this work, flocculation properties of cassava starch grafted polydiallyldimethylammonium chloride (polyDADMAC) with different grafting percentages were investigated. Flocculation performance was evaluated in simulated kaolin suspension. The grafting percentages used were 1.76 %, 14.84 %, and 21.98 %. The effectiveness of the flocculation was measured based on the reduction of the turbidity and total suspended solids (TSSs), zeta potential measurements, particle size, and atomic force microscopy imaging. Grafted polymers improved the removal rate of turbidity and TSS compared with gelatinized starch, and the removal rate increased with increasing grafting percentage and dosage.

  11. Preparation of metal adsorbent from poly(methyl acrylate)-grafted-cassava starch via gamma irradiation

    Science.gov (United States)

    Suwanmala, Phiriyatorn; Hemvichian, Kasinee; Hoshina, Hiroyuki; Srinuttrakul, Wannee; Seko, Noriaki

    2012-08-01

    Metal adsorbent containing hydroxamic acid groups was successfully synthesized by radiation-induced graft copolymerization of methyl acrylate (MA) onto cassava starch. The optimum conditions for grafting were studied in terms of % degree of grafting (Dg). Conversion of the ester groups present in poly(methyl acrylate)-grafted-cassava starch copolymer into hydroxamic acid was carried out by treatment with hydroxylamine (HA) in the presence of alkaline solution. The maximum percentage conversion of the ester groups of the grafted copolymer, % Dg=191 (7.63 mmol/g of MA), into the hydroxamic groups was 70% (5.35 mmol/g of MA) at the optimum condition. The adsorbent of 191%Dg had total adsorption capacities of 2.6, 1.46, 1.36, 1.15 and 1.6 mmol/g-adsorbent for Cd2+, Al3+, UO22+, V5+ and Pb2+, respectively, in the batch mode adsorption.

  12. Permeation of volatile compounds through starch films

    NARCIS (Netherlands)

    Yilmaz, G.; Jongboom, R.O.J.; Feil, H.; Dijk, van C.; Hennink, W.E.

    2004-01-01

    The aim of this study was to gain insight into the factors that affect the permeation of volatiles through starch films. These films were obtained by casting gelatinized starch/water/glycerol mixtures. The films were dried and conditioned under different conditions (temperature and relative humidity

  13. Nanocomposite-forming solutions based on cassava starch and laponite: viscoelastic and rheological characterization

    OpenAIRE

    2015-01-01

    Nanocomposites-forming solutions (NFS) based on cassava starch and laponite were prepared and next characterized by means of dynamic oscillatory and steady shear rheological tests to evaluate their ability to be processed by knife coating. The effects of speed (rpm) and homogenization time on the laponite dispersion characteristics were first analyzed. Laponite dispersions were affected by both process parameters. High speed (rpm), i.e. 20,000 or 23,000 rpm for 30 min or prolonged...

  14. Cassava starch edible coating incorporated with propolis on bioactive compounds in strawberries

    Directory of Open Access Journals (Sweden)

    Ariela Betsy Thomas

    2016-02-01

    Full Text Available ABSTRACT Strawberry is a fruit appreciated throughout the world due to its attractive quality attributes and stands out due to its high phenolic compound content, which positively contribute to biological properties of nutritional interest. The objective of this study was to evaluate the effect of cassava starch coatings incorporated with propolis combinations on the phytochemical content and the maintenance and increase of the strawberry antioxidant activity. The treatments were 3% cassava starch (CS, 3% cassava starch + 33% ethanolic propolis extract (CS + P33%, 3% cassava starch + 66% ethanolic propolis extract (CS + P66% and control (C. The fruits were stored at 4 °C ± 0.5 ºC and 90%RH for 16 days, making up a completely randomized design with 4 treatments and 5 time evaluations. Vitamin C, phenolic compound, anthocyanin, and antioxidant activity levels were evaluated through two methods. The coating with 66% of propolis promoted higher Vitamin C content than fruits submitted to the other treatments at 8 and 12 days of storage. For antioxidant activity, fruits treated with CS maintained a higher FRS percentage (free radical scavenging at all time evaluations. Control fruits presented higher anthocyanin content at the last evaluation time when the highest antioxidant capacity, by the ABTS method (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid, was observed in fruits with CS and CS + P66% treatments. There was an increase tendency of the phenolic content during storage in all evaluated fruits. The propolis concentrations used, however, were not sufficient to increase or maintain the antioxidant capacity and phenolic contents of strawberries.

  15. Optimization of single-cell-protein production from cassava starch using Schwanniomyces castellii.

    Science.gov (United States)

    Hongpattarakere, T; H-Kittikun, A

    1995-11-01

    Schwanniomyces castellii B5285 grew faster and produced greater biomass and higher protein yield than either S. alluvius ATCC 26074 or S. alluvius 81Y when these amylolytic yeasts were grown with 2% (w/v) cassava starch as sole C source. With 0.5% (w/v) glutamate as N source, S. castellii reached 7.12 g cell dry mass/l, with a protein yield of 6.4 g/100 g starch. The optimal agitation speed, aeration rate and pH for growth of this yeast in a fermenter were 400 rev/min, 1.67 vol./vol.min. and 5.0, respectively. Tween 80 at 0.1% increased cell dry mass to 8.90 g/l, cell yield to 44 g/100 g starch and protein yield to 7.4 g/100 g starch.

  16. Utilization of Cassava Starch in Copolymerisation of Superabsorbent Polymer Composite (SAPC

    Directory of Open Access Journals (Sweden)

    Akhmad Zainal Abidin

    2014-09-01

    Full Text Available Cassava starch was used as the main chain in the copolymerization of a superabsorbent polymer composite (SAPC based on acrylic acid and bentonite. The SAPC was synthesized through graft polymerization using nano-sized bentonite as reinforcement. The variables in this experiment were: bentonite concentration, acrylic acid to starch weight ratio, concentration of initiator, and cross linker. The product was characterized using FTIR, SEM and TGA-DSC. The results show that the polymerization reactions involved processes of incorporating starch chains as polymer backbone and grafting acrylic acid monomers onto it. The use of cassava starch in the polymerisation produced a very short reaction time (10-15 minutes, which led to SAPC production with higher efficiency and lower cost. Bentonite interacts with monomers via hydrogen and weak bonding, thus improving the thermal properties of the product. The maximum absorbance capacity obtained was at an acrylic acid to starch weight ratio of 5 and a concentration of initiator, cross linker and bentonite of 0.5, 0.05 and 2 weight percent, respectively. The product is suitable for agricultural and medical applications as well as common superabsorbent polymer applications.

  17. Performance of Cassava Starch as a Proton Exchange Membrane in a Dual Chambered Microbial Fuel Cell.

    Directory of Open Access Journals (Sweden)

    Livinus A. Obasi

    2012-01-01

    Full Text Available This research work shows the feasibility of power generation in a mediatorless dual chambered microbial fuel cell, utilizing cassava starch as the proton exchange membrane (PEM. The study employed swine house effluent (a serious environmental threat as the substrate (fuel (pH, 7.2, BOD: 1200mg/l, COD: 3800mg/l in the anode chamber prepared with a phosphate buffer solution (K2HPO4+KH2PO4, potassium ferry cyanide solution served as the oxygen acceptor in the cathode chamber using graphite electrodes, the cell operating at room temperature (27 ± 30C. The PEM (gelatinized cassava starch was prepared with varying degrees of modifications for three cells, ranging from the untreated pure starch (A, starch treated with 5.9% sodium chloride (B and starch modified with sodium alginate (a gum and activated carbon (C. The open circuit voltages (OCV and powerperformances of the three cells were monitored for ten days. Each of the cells was inoculated with the adopted consortium in soil solution obtained from mangrove forest. The maximum power outputs from the cells were 945.69mW/m2, 1068.54 mW/m2 and 570.83 mW/m2 for A, B and C respectively.

  18. A REVIEW ON BIODEGRADABLE STARCH BASED FILM

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    Hooman Molavi

    2015-04-01

    Full Text Available In recent years, biodegradable edible films have become very important in research related to food, due to their compatibility with the environment and their use in the food packaging industry. Various sources can be used in the production of biopolymers as biodegradable films that include polysaccharides, proteins and lipids. Among the various polysaccharides, starch due to its low price and its abundance in nature is of significant importance. Several factors affect the properties of starch films; such as the source which starch is obtained from, as well as the ratio of constituents of the starch. Starch films have advantages such as low thickness, flexibility and transparency though; there are some downsides to mention, such as the poor mechanical properties and water vapor permeability. Thus, using starch alone to produce the film will led to restrictions on its use. To improve the mechanical properties of starch films and also increases resistance against humidity, several methods can be used; including the starch modifying techniques such as cross linking of starch and combining starch with other natural polymers. Other methods such as the use of lipid in formulations of films to increase the resistance to moisture are possible, but lipids are susceptible to oxidation. Therefore, new approaches are based on the integration of different biopolymers in food packaging.

  19. Sugar-mediated semidian oscillation of gene expression in the cassava storage root regulates starch synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Jansson, Christer; Baguma, Yona; Sun, Chuanxin; Boren, Mats; Olsson, Helena; Rosenqvist, Sara; Mutisya, Joel; Rubaihayo, Patrick R.; Jansson, Christer

    2008-01-15

    Starch branching enzyme (SBE) activity in the cassava storage root exhibited a diurnal fluctuation, dictated by a transcriptional oscillation of the corresponding SBE genes. The peak of SBE activity coincided with the onset of sucrose accumulation in the storage, and we conclude that the oscillatory mechanism keeps the starch synthetic apparatus in the storage root sink in tune with the flux of sucrose from the photosynthetic source. When storage roots were uncoupled from the source, SBE expression could be effectively induced by exogenous sucrose. Turanose, a sucrose isomer that cannot be metabolized by plants, mimicked the effect of sucrose, demonstrating that downstream metabolism of sucrose was not necessary for signal transmission. Also glucose and glucose-1-P induced SBE expression. Interestingly, induction by sucrose, turanose and glucose but not glucose-1-P sustained an overt semidian (12-h) oscillation in SBE expression and was sensitive to the hexokinase (HXK) inhibitor glucosamine. These results suggest a pivotal regulatory role for HXK during starch synthesis. Abscisic acid (ABA) was another potent inducer of SBE expression. Induction by ABA was similar to that of glucose-1-P in that it bypassed the semidian oscillator. Both the sugar and ABA signaling cascades were disrupted by okadaic acid, a protein phosphatase inhibitor. Based on these findings, we propose a model for sugar signaling in regulation of starch synthesis in the cassava storage root.

  20. Direct detection of toxigenic Bacillus cereus in dietary complement for children and cassava starch

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    Jnnifer A. Sánchez

    2015-09-01

    Full Text Available Bacillus cereus is a food contaminant anda known human pathogen that can causeemetic and diarrheal syndromes. In this studywe evaluated the presence of toxigenic B.cereus by multiplex PCR directly in dietarycomplement for children and cassava starchsamples collected on Medellin, Colombia.Of 75 dietary complement for childrensamples evaluated, 70.7% were contaminatedwith toxigenic B. cereus and four differenttoxigenic consortia were detected: I: nheA,hblC, cytK (9.8%, II: nheA, hblC (2%,III: hblC, cytK (41.2%, IV: hblC (47%.Of 75 cassava starch samples, 44% werecontaminated with toxigenic B. cereus andfour different toxigenic consortia weredetermined: I: nheA, hblC, cytK (48.5%,II: nheA, hblC, cytK, cesB (3%, III: hblC,cytK (30.3%, IV: hblC (18.2%. In general,in dietary complement for children onlyenterotoxigenic consortia were detectedwhile in cassava starch the enterotoxigenicconsortia predominated over the emetic.Multiplex PCR was useful to detect toxigenicB. cereus contamination allowing directand simultaneous detection of all toxingenes in foods. This study is the first inColombia to evaluate toxigenic B. cereus,providing information of importance formicrobiological risk evaluation in driedfoods.

  1. Seasonal effects on the physico-chemical properties of starch from four cultivars of cassava

    Energy Technology Data Exchange (ETDEWEB)

    Asaoka, M.; Blanshard, J.M.V. (Nottingham Univ. (United Kingdom). Dept. of Applied Biochemistry and Food Science); Rickard, J.E. (Natural Resources Inst., Chatham (United Kingdom))

    1991-12-01

    Four varieties of cassava plants were cultivated at CIAT in Columbia and harvested on four different occasions with a view to evaluating whether there was any relationship between the texture of the cooked roots and the constituent starch. The organoleptic qualities of the cooked roots showed considerable differences in 'glassiness' and hardness of texture, both between varieties and times of harvest. The starch granules were isolated and examined by a variety of techniques. The size of the granules did vary with the seasons but there were only minor differences in the X-ary crystallinity, the elution patterns of iso-amylase-debranched material (including the amylose content), the proximate composition of the starch and the time course of digestion by glucoamylase. None of these provided a basis for explaining the differences in cooked texture. (orig.).

  2. Desenvolvimento e avaliação da eficácia de filmes biodegradáveis de amido de mandioca com nanocelulose como reforço e com extrato de erva-mate como aditivo antioxidante Development and evaluation of the effectiveness of biodegradable films of cassava starch with nanocelulose as reinforcement and yerba mate extract as an additive antioxidant

    Directory of Open Access Journals (Sweden)

    Bruna Aparecida Souza Machado

    2012-11-01

    Full Text Available O objetivo do trabalho foi desenvolver uma embalagem biodegradável utilizando como matriz polimérica o amido de mandioca plastificada com glicerol e reforçada com a incorporação de nanocelulose da fibra de coco, bem como, avaliar o efeito da adição de um aditivo natural (erva-mate nas formulações de nanobiocompósitos com ação antioxidante. Os nanocristais de celulose (L/D=39 foram obtidos por hidrólise ácida com H2SO4 a 65%. Os filmes foram preparados por casting contendo 4,5 e 6,0% de amido, 0,5 e 1,5% de glicerol, 0,3% de nanocelulose e 20% de extrato de erva-mate. O armazenamento do azeite de dendê embalado com os filmes contendo o aditivo foi monitorado por 40 dias sob condições de oxidação acelerada (63%UR/30°C. Constatou-se que, à medida que aumentam as perdas de Polifenóis Totais nos filmes, ocorre um menor aumento do Índice de Peróxidos do produto embalado, demonstrando, assim, que, ao invés do produto, os compostos da embalagem é quem estão sofrendo oxidação. A incorporação de extrato de erva-mate não alterou as propriedades mecânicas e de barreira desses filmes.The objective was to develop biodegradable packaging using a polymer matrix as the cassava starch plasticized with glycerol and reinforced with the incorporation of nanocelulose of coconut fiber, as well as to evaluate the effect of the addition of an additive nature (yerba mate in nanobiocompósitos formulations with antioxidant action. The nanocrystal cellulose (L/D=39 were obtained by acid hydrolysis with 65% H2SO4. The films were prepared by casting containing 4.5 and 6.0% starch, 0.5 and 1.5% glycerol, 0.3% nanocelulose and 20% extract of yerba mate. The palm oil storage packed with films containing the additive was monitored for 40 days under conditions of accelerated oxidation (63%UR/30°C. It was found that as the losses increase polyphenol films, there is a smaller increase of the peroxide value of the packaged product, thus

  3. Saccharification of cassava starch by Saccharomycopsis fibuligera YCY1 isolated from Loog-Pang (rice cake starter

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    Aran H-Kittikun

    2008-04-01

    Full Text Available The main objectives of this study were to select amylolytic yeasts from Loog-Pang, a traditional starter culture for production of alcoholic foods and drinks in southern Thailand, and to optimize the saccharification of cassava starch to reducing sugar by the selected yeast isolate. Seventy-four yeast isolates were obtained from ten samples of Loog-Pang. The isolates were tested for amylolytic activity on Yeast-Peptone Cassava medium (YPC contained 30 g/l of cassava starch.Only three isolates showed amylolytic activity which produced clear zone on the YPC agar. The best amylolytic strain with clear zone of 8 mm was identified by 26s rDNA as Saccharomycopsis fibuligera. The optimum medium for saccharification by Saccharomycopsis fibuligera. YCY1 was only 50 g/l of cassava starch in distilled water without nitrogen sources added and pH adjustment. The optimal saccharification conditions were 200 ml cassava starch (50 g/l in 500 ml Erlenmeyer flask, shaking at 100 rpm and 37oC. Under these conditions, the highest reducing sugar was obtained 46±0.53 g/l after 120 h cultivation (84% of the theoretical yield.

  4. Summarization of Cassava Starch Deep Processing Products%木薯淀粉深加工产品概述

    Institute of Scientific and Technical Information of China (English)

    姚丹; 梁智

    2012-01-01

    木薯是广西的一大经济作物,是"三薯"作物之一。木薯的块茎是做淀粉的主要原料,木薯淀粉以其特有的特性,制淀粉和深加工制变性淀粉,具有优势,应用也十分广泛。除此之外,其它衍生物产品应用广泛,不断研究出新的产品。%Cassava is one important economic crop in Guangxi,one of three main tuber crops(cassava,potato and sweet potato) in the world.Tuber of cassava is key raw material for production of starch.Native starch and modified starch made from cassava possess great advantages and can be applied in a wide variety of fields.Moreover,derivatives of cassava starch can be used for many aims and new products keep emerging from continuous research.

  5. Antimicrobial nanostructured starch based films for packaging.

    Science.gov (United States)

    Abreu, Ana S; Oliveira, M; de Sá, Arsénio; Rodrigues, Rui M; Cerqueira, Miguel A; Vicente, António A; Machado, A V

    2015-09-20

    Montmorillonite modified with a quaternary ammonium salt C30B/starch nanocomposite (C30B/ST-NC), silver nanoparticles/starch nanocomposite (Ag-NPs/ST-NC) and both silver nanoparticles/C30B/starch nanocomposites (Ag-NPs/C30B/ST-NC) films were produced. The nanoclay (C30B) was dispersed in a starch solution using an ultrasonic probe. Different concentrations of Ag-NPs (0.3, 0.5, 0.8 and 1.0mM) were synthesized directly in starch and in clay/starch solutions via chemical reduction method. Dispersion of C30B silicate layers and Ag-NPs in ST films characterized by X-ray and scanning electron microscopy showed that the presence of Ag-NPs enhanced clay dispersion. Color and opacity measurements, barrier properties (water vapor and oxygen permeabilities), dynamic mechanical analysis and contact angle were evaluated and related with the incorporation of C30B and Ag-NPs. Films presented antimicrobial activity against Staphylococcus aureus, Escherichia coli and Candida albicans without significant differences between Ag-NPs concentrations. The migration of components from the nanostructured starch films, assessed by food contact tests, was minor and under the legal limits. These results indicated that the starch films incorporated with C30B and Ag-NPs have potential to be used as packaging nanostructured material.

  6. Performance of Cassava Starch as a Proton Exchange Membrane in a Dual Chambered Microbial Fuel Cell.

    OpenAIRE

    Livinus A. Obasi; Charles C. Opara; Akuma Oji

    2012-01-01

    This research work shows the feasibility of power generation in a mediatorless dual chambered microbial fuel cell, utilizing cassava starch as the proton exchange membrane (PEM). The study employed swine house effluent (a serious environmental threat) as the substrate (fuel) (pH, 7.2, BOD: 1200mg/l, COD: 3800mg/l) in the anode chamber prepared with a phosphate buffer solution (K2HPO4+KH2PO4), potassium ferry cyanide solution served as the oxygen acceptor in the cathode chamber using graphite ...

  7. Thermoanalytical and starch content evaluation of cassava bagasse as agro-industrial residue

    Directory of Open Access Journals (Sweden)

    Luiz Gustavo Lacerda

    2009-11-01

    Full Text Available Starch nutritional fractions as well as thermal properties and other analysis are essential for food and industrial application. Cassava bagasse is an important agro-industrial residue and its starch content was evaluated using two alternative methods. Thermal characterization and microscopy analyses helped to understand how hydrolysis digests starchy fraction of cassava bagasse. The melting point of cassava starch occurred at 169.2ºC. Regarding TG analyses, after moisture content, there were observed two main mass losses for all samples. Results suggest hydrolysis carried out using enzyme is less effective in order to convert total starch content in cassava bagasse. However, using sulfuric acid, fibers are affected by analyses conditions.As frações nutricionais bem como as propriedades térmicas e outras análises são essenciais para a indústria de alimentos e suas aplicações O bagaço de mandioca é um importante resíduo agroindustrial e seu teor de amido foi avaliado por dois métodos alternativos. A caracterização por análise térmica e microscopia ajudou na compreensão de como a hidrólise digere a fração amilácea do bagaço de mandioca, O ponto de fusão foi de 170ºC, a análise termogravimétrica (TG mostrou após a perda de umidade do material, duas principais perdas de massa em todas as amostras analisadas. Os resultados sugerem que a hidrólise enzimática é menos eficiente na conversão total de amido no bagaço de mandioca. No entanto, o uso de ácido sulfúrico degradou até mesmo a parcela fibrosa do material, afetando as condições de análise.

  8. Extracellular amylase(s) production by fungi Botryodiplodia theobromae and Rhizopus oryzae grown on cassava starch residue.

    Science.gov (United States)

    Ray, R C

    2004-10-01

    The fungi Botryodiplodia theobromae and Rhizopus oryzae produce extracellular amylase when grown on a liquid medium containing 2% (WN) soluble starch or cassava starch residue(CSR) (as starch equivalent), a waste generated after extraction of starch from cassava, as the sole carbon source. Using CSR as the sole carbon source, the highest amylase activity of 3.25 and 3.8 units (mg, glucose released x ml(-1) x h(-1)) were obtained in shake flask cultures during the late stationary phase of growth of B. theobromae and R. oryzae, respectively. These values were slightly lower than the values obtained using soluble starch as the carbon source. Maximum enzyme synthesis in CSR incorporated medium occurred at the growth temperature of 30 degrees C and pH 6.0. Presence of inorganic NH4+ salts like ammonium acetate and ammonium nitrate in culture medium yielded more amylase than the other nitrogen sources. Amylase(s) production in the controlled environment of a Table-Top glass Jar Fermenter (2-L capacity) was 4.8 and 5.1 units for B. theobromae and R. oryzae, respectively using CSR as the carbon substrate. It is concluded that CSR, a cheap agricultural waste obtained after starch extraction from cassava could replace soluble starch as carbon substrate for commercial production of fungal amylase(s).

  9. AMMI Model for Interpreting Clone-Environment Interaction in Starch Yield of Cassava

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    SHOLIHIN

    2011-03-01

    Full Text Available The aim of the study was to analyze the interaction between clone and environment for starch yield in six month-old plants of cassava clones based on additive main effects and multiplicative interaction (AMMI model. The experiments were conducted on mineral soil in four different locations: Lumajang (inceptisol, Kediri (entisol, Pati (alfisol, and Tulangbawang (ultisol. The experiments were carried out during 2004-2005, using a split plot design withthree replications. The main plots were the simple and the improved technology. The clones used were fifteen clones. Parameter recorded was starch yield (kg/ha of the 6 month old plants. The data were analyzed using the AMMI model. Based on the AMMI analysis, environmental factors being important in determining the stability of the starch yield were soil density for subsoil, pH of topsoil, and the maximum air humidity four months after planting. The clones of CMM97001-87, CMM97002-183, CMM97011-191, CMM97006-44, and Adhira 4 were identified as stable clones in starch yield within 6 month-old plants. CMM97007-235 was adapted to maximum relative humidity 4 months after planting and to lower pH of topsoil, whereas, MLG 10311 was adapted to lower bulk density. The mean starch yield of MLG 10311 was the highest six months after planting.

  10. Effect of Soil Burial on Tensile Properties of Polypropylene/Plasticized Cassava Starch Blends

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    Henry C. Obasi

    2013-01-01

    Full Text Available Polypropylene (PP/plasticized cassava starch (PCS blended with and without compatibilizer (polypropylene-graft-maleic anhydride (PP-g-MA via melt blending were prepared for soil burial which lasted for 90 days. Plasticized starch loadings of 0, 10, 20, 30, 40, and 50 wt.% were used, while pp-g-ma was used at 10 wt.% based on starch weight. The PP/PCS and PP/PCS/PP-G-MA blends were evaluated for their tensile properties. It was observed that the tensile strength, elongation at break, and young’s modulus decreased with increases in soil burial time as well as starch content for PP/PCS blends. Similar treads for the tensile properties were observed for PP/PCS/PP-g-MA, but with higher properties as compared to uncompatibilized blends. However, the tensile properties for both PP/PCS and PP/PCS/PP-g-Ma decrease with increases in starch loading and also as the burial period progressed.

  11. Characterization of cassava starch based foam blended with plant proteins, kraft fiber, and palm oil.

    Science.gov (United States)

    Kaisangsri, Nattapon; Kerdchoechuen, Orapin; Laohakunjit, Natta

    2014-09-22

    Cassava starch foam (CSF) trays blended with zein, gluten, soy protein, kraft fiber, and palm oil at various concentrations: 0, 5, 10 and 15% by weight of starch, were characterized. The addition of zein and gluten into CSF resulted in consolidated and homogeneous structural foams compared to its controls. Moreover, the flexural and compressive strength increased with increasing kraft, zein and gluten. CSF containing 15% kraft gave the highest flexural and compressive strength. However, the addition of palm oil into CSF gave the lowest flexural strength and compressive strength. The observed water absorption and water solubility index of CSFs blended with 15% zein and 15% gluten protein was lowest. Although kraft, zein and gluten could improve mechanical properties, water absorption and water solubility were greater than the expanded polystyrene foam (EPS). The CSF trays in this study might be an alternative for packing low water content foods.

  12. Changes in physical properties of extruded sour cassava starch and quinoa flour blend snacks

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    Lívia Giolo Taverna

    2012-12-01

    Full Text Available Given the broad acceptance of sour cassava starch biscuits in Brazil and the nutritional quality of quinoa flour, this study aimed to evaluate the effect of extrusion temperature, screw speed, moisture, and amount of quinoa flour on the physical properties of puffed snacks. Extrusion process was carried out using a single-screw extruder in a factorial central composite design with four factors. Effects of moisture and amount of quinoa flour on the expansion index and specific volume of snacks were observed. There was a pronounced increase in water solubility index of blends with the extrusion process with significant effects of all process parameters on the WSI. Higher water absorption index (WAI was observed under high temperature, low moisture, and lower quinoa flour amount. Temperature and amount of quinoa flour influenced the color of the snacks. A positive quadratic effect of quinoa flour on hardness of products was observed. Blends of sour cassava starch and quinoa flour have good potential for use as raw material in production of extruded snacks with good physical properties.

  13. Biobased Polystyrene Foam-like Material from Crosslinked Cassava Starch and Nanocellulose from Sugarcane Bagasse

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    Parichat Phaodee

    2014-11-01

    Full Text Available This research aimed to study the effect of lignin, natural rubber latex (NRL, nanocellulose, and talc on production of biobased foam using cassava starch as matrix. Comparison study on lignin extraction from sugarcane bagasse (SCB for different types of base (KOH and NaOH, concentration (10 %w/w and 40 %w/w, and temperatures (60 C for 3 h and 120 C for 1 h was performed. The most suitable isolation condition giving the highest yield of lignin and lowest hemicellulose contamination was 40 %KOH at 120 oC for 1 h. A mechanical method was superior to a chemical method for cellulose size reduction owing to more appropriate size distribution and uniformity of nanocellulose. The most favorable proportion of foam contained 20% nanocellulose, 3% talc, 0.1% NRL, 38.5% water, and 76.9% crosslinked cassava starch. These conditions resulted in favorable flexural strength, modulus, and percentage of elongation, analogous to polystyrene foam. An appropriate amount of added lignin increased the elasticity of biofoam.

  14. Use of dried waste of cassava starch extraction for feeding lactating cows

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    TATIANE FERNANDES

    2015-06-01

    Full Text Available The aim of this study was to determine the best level of utilization of dried waste of cassava starch extraction (WCSEd as a substitute for corn for lactating cows. Four lactating cows were fed diets with increasing levels (0%, 33%, 66% and 100% of WCSEd as a substitute for corn. The intake and digestibility of dry matter and nutrients, milk production and composition, blood parameters of glucose and urea and microbial synthesis of the diets were evaluated. There was a reduction in dry matter intake, organic matter, ether extract and total carbohydrate, and increased intake of acid detergent fiber. Nutrient digestibility was not affected while the synthesis of microbial protein increased. These changes resulted in reduced milk production, without altering the efficiency of production or the constituents of milk, with a decreasing effect on daily production of lactose, solids and minerals. Metabolic parameters, glucose and urea nitrogen in plasma, remained within appropriate levels. The dried residue from the extraction of cassava starch can be used as feed for dairy cows to replace up to 100% of the corn ration. However, its use promotes a reduction in intake of dry matter and nutrients as well as a reduction in the production of milk, with impacts on the profitability of the product.

  15. Experimental study on drying kinetic of cassava starch in a pneumatic drying system

    Science.gov (United States)

    Suherman, Kumoro, Andri Cahyo; Kusworo, Tutuk Djoko

    2015-12-01

    The aims of this study are to present the experimental research on the drying of cassava starch in a pneumatic dryer, to describe its drying curves, as well as to calculate its thermal efficiency. The effects of operating conditions, namely the inlet air temperature (60-100 °C) and solid-gas flow rate ratio (Ms/Mg 0.1-0.3) were studied. Heat transfer is accomplished through convection mechanism in a drying chamber based on the principle of direct contact between the heated air and the moist material. During the drying process, intensive heat and mass transfer between the drying air and the cassava starch take place. In order to meet the SNI standards on solid water content, the drying process was done in two cycles. The higher the temperature of the drying air, the lower the water content of the solids exiting the dryer. Thermal efficiency of the 2nd cycle was found to be lower than the 1st cycle.

  16. High temperature simultaneous saccharification and fermentation of starch from inedible wild cassava (Manihot glaziovii) to bioethanol using Caloramator boliviensis.

    Science.gov (United States)

    Moshi, Anselm P; Hosea, Ken M M; Elisante, Emrode; Mamo, G; Mattiasson, Bo

    2015-03-01

    The thermoanaerobe, Caloramator boliviensis was used to ferment starch hydrolysate from inedible wild cassava to ethanol at 60°C. A raw starch degrading α-amylase was used to hydrolyse the cassava starch. During fermentation, the organism released CO2 and H2 gases, and Gas Endeavour System was successfully used for monitoring and recording formation of these gaseous products. The bioethanol produced in stoichiometric amounts to CO2 was registered online in Gas Endeavour software and correlated strongly (R(2)=0.99) with values measured by HPLC. The organism was sensitive to cyanide that exists in cassava flour. However, after acclimatisation, it was able to grow and ferment cassava starch hydrolysate containing up to 0.2ppm cyanide. The reactor hydrogen partial pressure had influence on the bioethanol production. In fed-batch fermentation by maintaining the hydrogen partial pressure around 590Pa, the organism was able to ferment up to 76g/L glucose and produced 33g/L ethanol.

  17. Carboxymethylation of Cassava Starch in Different Solvents and Solvent-Water Mixtures: Optimization of Reaction Conditions

    Science.gov (United States)

    Nwokocha, Louis M.; Ogunmola, Gabiel B.

    The influence of reaction medium on carboxymethylation process was investigated by treating cassava starch with sodium monochloroacetate in different solvents and solvent-water mixtures under alkaline conditions. The amount of carboxyl groups introduced into the starch moiety was determined titrimetrically and used to calculate the Degree of Substitution (DS) and Reaction Efficiency (RE). The results showed that carboxymethylation is significantly affected by the nature of reaction medium at p<0.05. Carboxymethylation in different solvent-water mixtures showed that aqueous 80% n-propanol offered the best medium for carboxymethylation. Optimization of reaction conditions in aqueous 80% n-propanol showed that the best condition for carboxymethylation was at starch-liquor ratio of 1:3, NaOH/reagent molar ratio of 4.0 and reagent-starch molar ratio of 0.35. An increase in temperature was required to effect the reaction at shorter time. At 55°C the highest values of DS and RE achieved in 0.5 h would require three hours to achieve the same values of DS and RE at 45°C.

  18. Production and characterization of thermoplastic cassava starch, functionalized poly(lactic acid), and their reactive compatibilized blends

    Science.gov (United States)

    Detyothin, Sukeewan

    Cassava starch was blended with glycerol using a co-rotating twin-screw extruder (TSE). Thermoplastic cassava starch (TPCS) at a ratio of 70/30 by weight of cassava/glycerol was selected and further blended with other polymers. TPCS sheets made from compression molding had low tensile strength (0.45 +/- 0.05 MPa) and Young's modulus (1.24 +/- 0.58 MPa), but moderate elongation at break (83.0 +/- 0.18.6%), medium level of oxygen permeability, and high water vapor permeability with a very high rate of water absorption. TPCS was blended with poly(lactic acid) (PLA) at various ratios by using a TSE. The blend resins exhibited good properties such as increased thermal stability (Tmax) and crystallinity of PLA, and improved water sensitivity and processability of TPCS. PLA and TPCS exhibited a high interfacial tension between the two phases of 7.9 mJ·m -2, indicating the formation of an incompatible, immiscible blend. SEM micrographs showed a non-homogeneous distribution of TPCS droplets in the PLA continuous phase. TEM micrographs of the blend films made by cast-film extrusion showed coalescence of the TPCS droplets in the PLA continuous phase of the blend, indicating that the compatibility between the polymer pair needs to be improved. A response surface methodology (RSM) design was used to analyze the effects of maleic anhydride (MA) and 2,5-bis(tert-butylperoxy)-2,5-dimethylhexane (Luperox or L101) contents, and TSE screw speed on the degree of grafted MA and number average molecular weight (Mn) of functionalized PLA (PLA-g-MA), a reactive compatibilizer. PLA-g- MA made by reactive extrusion had an array of colors depending on the content of L101 and MA used. New FTIR peaks suggested that MA was grafted onto the PLA backbone and oligomeric MA may occur. Increasing L101 increased the degree of grafting and decreased Mn, but the Mn of the PLA-g-MA's produced with a high amount of L101 was stable during storage. MA exhibited an optimum concentration for maximizing the

  19. Proteomics Profiling Reveals Carbohydrate Metabolic Enzymes and 14-3-3 Proteins Play Important Roles for Starch Accumulation during Cassava Root Tuberization.

    Science.gov (United States)

    Wang, Xuchu; Chang, Lili; Tong, Zheng; Wang, Dongyang; Yin, Qi; Wang, Dan; Jin, Xiang; Yang, Qian; Wang, Liming; Sun, Yong; Huang, Qixing; Guo, Anping; Peng, Ming

    2016-01-01

    Cassava is one of the most important root crops as a reliable source of food and carbohydrates. Carbohydrate metabolism and starch accumulation in cassava storage root is a cascade process that includes large amounts of proteins and cofactors. Here, comparative proteomics were conducted in cassava root at nine developmental stages. A total of 154 identified proteins were found to be differentially expressed during starch accumulation and root tuberization. Many enzymes involved in starch and sucrose metabolism were significantly up-regulated, and functional classification of the differentially expressed proteins demonstrated that the majority were binding-related enzymes. Many proteins were took part in carbohydrate metabolism to produce energy. Among them, three 14-3-3 isoforms were induced to be clearly phosphorylated during storage root enlargement. Overexpression of a cassava 14-3-3 gene in Arabidopsis thaliana confirmed that the older leaves of these transgenic plants contained higher sugar and starch contents than the wild-type leaves. The 14-3-3 proteins and their binding enzymes may play important roles in carbohydrate metabolism and starch accumulation during cassava root tuberization. These results not only deepened our understanding of the tuberous root proteome, but also uncovered new insights into carbohydrate metabolism and starch accumulation during cassava root enlargement.

  20. Effect of fermentation conditions on biohydrogen production from cassava starch by anaerobic mixed cultures

    Science.gov (United States)

    Tien, Hai M.; Le, Kien A.; Tran, An T.; Le, Phung K.

    2016-06-01

    In this work, a series of batch tests were conducted to investigate the effect of pH, temperature, fermentation time, and inoculums ratio to hydrogen production using cassava starch as a substrate. The statistical analysis of the experiment indicated that the significant effects for the fermentation yield were the main effect of temperature, pH and inoculums ratio. It was fouund that the suitable fermentation conditions of biohydrogen production should be at temperature 40 ° C; pH 6.5, inoculums to medium ratio 10 % and COD operation at 4800 g/mL. The maximum value of hydrogen volume produced was 76.22 mL. These affected has been evaluated and the result can be used as an reference for the pilot or industrial biohydrogen production.

  1. Quantitative trait loci and candidate genes associated with starch pasting viscosity characteristics in cassava (Manihot esculenta Crantz).

    Science.gov (United States)

    Thanyasiriwat, T; Sraphet, S; Whankaew, S; Boonseng, O; Bao, J; Lightfoot, D A; Tangphatsornruang, S; Triwitayakorn, K

    2014-01-01

    Starch pasting viscosity is an important quality trait in cassava (Manihot esculenta Crantz) cultivars. The aim here was to identify loci and candidate genes associated with the starch pasting viscosity. Quantitative trait loci (QTL) mapping for seven pasting viscosity parameters was carried out using 100 lines of an F1 mapping population from a cross between two cassava cultivars Huay Bong 60 and Hanatee. Starch samples were obtained from roots of cassava grown in 2008 and 2009 at Rayong, and in 2009 at Lop Buri province, Thailand. The traits showed continuous distribution among the F1 progeny with transgressive variation. Fifteen QTL were identified from mean trait data, with Logarithm of Odds (LOD) values from 2.77-13.01 and phenotype variations explained (PVE) from10.0-48.4%. In addition, 48 QTL were identified in separate environments. The LOD values ranged from 2.55-8.68 and explained 6.6-43.7% of phenotype variation. The loci were located on 19 linkage groups. The most important QTL for pasting temperature (PT) (qPT.1LG1) from mean trait values showed largest effect with highest LOD value (13.01) and PVE (48.4%). The QTL co-localised with PT and pasting time (PTi) loci that were identified in separate environments. Candidate genes were identified within the QTL peak regions. However, the major genes of interest, encoding the family of glycosyl or glucosyl transferases and hydrolases, were located at the periphery of QTL peaks. The loci identified could be effectively applied in breeding programmes to improve cassava starch quality. Alleles of candidate genes should be further studied in order to better understand their effects on starch quality traits.

  2. Fragrant starch-based films with limonene

    Directory of Open Access Journals (Sweden)

    Adrian K. Antosik

    2017-02-01

    Full Text Available Novel fragrant starch-based films with limonene were successfully prepared. Biodegradable materials of natural origin were used and the process was relatively simple and inexpensive. The effect of limonene on physicochemical properties of starch-based films (moisture absorption, solubility in water, wettability, mechanical properties were compared to glycerol plasticized system. Taking into consideration that the obtained materials could also exhibit bactericidal and fungicidal properties, the studies with Escherichia coli, Candida albicans and Aspergillus niger were performed. Such a material could potentially find application in food packaging (e.g. masking unpleasant odors, hydrophilic starch film would prevent food drying, or in agriculture (e.g. for seed encapsulated tapes.

  3. Envejecimiento de Almidones Termoplásticos Agrios de Yuca y Nativos de Papa por Microscopía de Fuerza Atómica Ageing of Sour Cassava and Native Potato Thermoplastic Starches by Atomic Force Microscopy

    Directory of Open Access Journals (Sweden)

    Harold A Acosta

    2006-01-01

    Full Text Available En este trabajo, se determinó la topografía de almidones termoplásticos (TPS agrio de yuca y nativo de papa, mediante microscopía de fuerza atómica (AFM, durante un periodo de 120 días de almacenamiento. Mezclas de almidones agrios (fermentados de yuca y nativo de papa, y glicerina, se procesaron en un extrusor de husillo sencillo. Láminas de TPS agrio de yuca (SCTPS y nativo de papa (NPTPS, se observaron y midieron por AFM (en modo contacto. Sus superficies mostraron incremento en rugosidad y partes lisas solo a altos contenidos de plastificante, pero SCTPS siempre tuvo menor rugosidad que NPTPS, debido a la fermentación natural del almidón agrio. Estos cambios se relacionaron con el tamaño, la forma del gránulo y particularmente con el contenido de plastificante. Los NPTPS de mayor rugosidad presentaron separación de fases a los 120 días, dada la retrogradación de las moléculas del almidón, que tienden a formar cristalitos. Estos resultados indican que el almidón agrio de yuca puede retardar la retrogradación de almidones termoplásticos, lo cual es importante durante el desarrollo de nuevos empaques biodegradables.This study reports on the topography of thermoplastic starches (TPS from sour cassava and native potato using atomic force microscopy (AFM, over a 120 day-storage period. Mixtures of sour cassava (fermented and native potato starches plus glycerine, were processed using a single-screw extruder. Sour cassava thermoplastic starch (SCTPS and native potato thermoplastic starch (NPTPS films were observed and measured by AFM (in contact mode. Their surfaces showed increased rugosity, and smooth parts only at high plasticizer content. However, SCTPS always had lower rugosity than NPTPS, due to the natural fermentation of sour cassava starch. These changes were related to starch granule size and shape, and particularly to plasticizer content. NPTPS with higher rugosity presented phase separation at 120 days, due to

  4. Production of Starch Based Bioplastic from Cassava Peel Reinforced with Microcrystalline Celllulose Avicel PH101 Using Sorbitol as Plasticizer

    Science.gov (United States)

    Maulida; Siagian, M.; Tarigan, P.

    2016-04-01

    The production of starch based bioplastics from cassava peel reeinforced with microcrystalline cellulose using sorbitol as plasticizer were investigated. Physical properties of bioplastics were determined by density, water uptake, tensile strength and Fourier Transform Infrared Spectroscopy. Bioplastics were prepared from cassava peel starch plasticized using sorbitol with variation of 20; 25; 30% (wt/v of sorbitol to starch) reinforced with microcrystalline celllulose (MCC) Avicel PH101 fillers with range of 0 to 6% (wt/wt of MCC to starch). The results showed improvement in tensile strength with higher MCC content up to 9, 12 mpa compared to non-reinforced bioplastics. This could be mainly attributed to the strong hydrogen bonds between MCC and starch. On the contrary, the addition of MCC decreased the elongation at break, density and water uptake. Fourier Transform Infrared Spectroscopy showed the functional groups of bioplastics, which the majority of O-H groups were found at the bioplastics with reinforcing filler MCC that represented substantial hydrogen bonds. The highest tensile strength value was obtained for bioplastic with MCC content 6% and sorbitol content 20%. With good adhesion between MCC and starch the production of bioplastics could be widely used as a substitute for conventional plastics with more benefits to the environment.

  5. Effect of genotype and genotype by environment interaction on total cyanide content, fresh root, and starch yield in farmer-preferred cassava landraces in Tanzania.

    Science.gov (United States)

    Mtunguja, Mariam K; Laswai, Henry S; Kanju, Edward; Ndunguru, Joseph; Muzanila, Yasinta C

    2016-11-01

    High starch yield is the most important trait for commercialized cassava starch production. Furthermore, cyanide present in cassava roots poses a health challenge in the use of cassava for food. Cassava genotypes have varying maturity periods that are also environmental dependent. This study aimed at identifying suitable cultivars and optimum time of harvest to maximize starch production across three environments. The study found significant difference between genotypes, locations, harvest period, and all the interactions (P ≤ 0.001) for all traits analyzed. Kiroba recorded high starch yields of 17.4, 12.7, and 8.2 t ha(-1) at Chambezi, Amani, and Magadu, respectively. Kilusungu recorded highest cyanide content of 300-400 ppm across all locations but Kiroba recorded highest values of 800 ppm, 15 months after planting at Chambezi. Genotype by environment (GGE) biplot analysis revealed that Kiroba was a superior cultivar in terms of starch yield. Kilusungu recorded highest cyanide content and average starch yield, therefore suitable for use in starch production. The study confirmed effect of genotype and genotype by environment interaction, Kiroba cultivar was superior in terms of starch yield and maximum starch yield was obtained at 9 months after planting. Nyamkagile and Kibandameno had the lowest cyanide content across all environments.

  6. Mechanical properties and solubility in water of corn starch-collagen composite films: Effect of starch type and concentrations.

    Science.gov (United States)

    Wang, Kun; Wang, Wenhang; Ye, Ran; Liu, Anjun; Xiao, Jingdong; Liu, Yaowei; Zhao, Yana

    2017-02-01

    This study investigated the possibility of enhancing the properties of collagen with three different maize starches: waxy maize starch, normal starch, and high amylose starch. Scanning electron microscopy images revealed that starch-collagen films had a rougher surface compared to pure collagen films which became smoother upon heating. Amylose starch and normal starch increased the tensile strength of unheated collagen films in both dry and wet states, while all starches increased tensile strength of collagen film by heating. Depending upon the amylose content and starch concentrations, film solubility in water decreased with the addition of starch. DSC thermograms demonstrated that addition of all starches improved the thermal stability of the collagen film. Moreover, X-ray diffraction results indicated that except for high amylose starch, the crystallinity of both starch and collagen was significantly decreased when subject to heating. FTIR spectra indicated that intermolecular interactions between starch and collagen were enhanced upon heating.

  7. Low Density Wood-Based Particleboards Bonded with Foamable Sour Cassava Starch: Preliminary Studies

    Directory of Open Access Journals (Sweden)

    Sandra Monteiro

    2016-10-01

    Full Text Available This work investigates the feasibility of producing low density particleboards using an adhesive system based on sour cassava starch, taking advantage of its adhesive and self-expansion properties. Relevant properties of the produced particleboards were evaluated according to European Standards including: density, internal bond, moisture content and thickness swelling. Low density particleboards were produced with densities between 207 kg/m3 and 407 kg/m3. The best performance corresponded to particleboard with a density of 318 kg/m3, an internal bond strength of 0.67 N/mm2, and a thickness swelling of 8.7%. These values meet the standard requirements of general purpose lightweight boards for use in dry conditions. Heat post-treatment (24 h at 80 °C led to lower internal bond strength, due to retrogradation (recrystallization of amylose and amylopectin chains upon cooling causing higher rigidity of the starch binder. However, it showed to have a significant effect on decreasing the thickness swelling.

  8. Effect of pectin particles and cotton fibers on properties of thermoplastic cassava starch composites

    Directory of Open Access Journals (Sweden)

    Jutarat Prachayawarakorn

    2016-04-01

    Full Text Available Due to poor mechanical properties and high water uptake of thermoplastic starch (TPS, this research focused on property improvement of thermoplastic cassava starch (TPCS using natural compatible polymers, i.e. pectin particles and cotton fibers. Different TPCS composites, reinforced by the pectin particles and/or the cotton fibers, were compounded and shaped using an internal mixer and a compression molding machine, respectively. It was found from infrared (IR spectra that the peak position of O-H stretching of the TPCS polymer clearly shifted to lower wavenumber by the addition of the pectin particles and/or the cotton fibers. Moreover, the significant increase of stress at maximum load and Young’s modulus of the TPCS/pectin particle and the TPCS/cotton fiber composites was observed. The drop of water uptake was also found when the cotton fibers were incorporated into the TPCS matrix with/without pectin particles. In addition, X-Ray Diffraction, Scanning Electron Microscopy and Thermogravimetric Analysis were used to characterize different TPCS composites.

  9. A Study of Specific Heat Capacity Functions of Polyvinyl Alcohol- Cassava Starch Blends

    Science.gov (United States)

    Sin, Lee Tin; Rahman, W. A. W. A.; Rahmat, A. R.; Morad, N. A.; Salleh, M. S. N.

    2010-03-01

    The specific heat capacity ( C sp) of polyvinyl alcohol (PVOH) blends with cassava starch (CSS) was studied by the differential scanning calorimetry method. Specimens of PVOH-CSS blends: PPV37 (70 mass% CSS) and PPV46 (60 mass% CSS) were prepared by a melt blending method with glycerol added as a plasticizer. The results showed that the specific heat capacity of PPV37 and PPV46 at temperatures from 330 K to 530 K increased from (2.963 to 14.995) J· g-1 · K-1 and (2.517 to 14.727) J · g-1· K-1, respectively. The specific heat capacity of PVOH-CSS depends on the amount of starch. The specific heat capacity of the specimens can be approximated by polynomial equations with a curve fitting regression > 0.992. For instance, the specific heat capacity (in J · g-1 · K-1) of PPV37 can be expressed by C sp = -17.824 + 0.063 T and PPV46 by C sp = -18.047 + 0.061 T, where T is the temperature (in K).

  10. The thermal, rheological and structural properties of cassava starch granules modified with hydrochloric acid at different temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Beninca, Cleoci; Colman, Tiago Andre Denck [State University of Ponta Grossa - UEPG, Av. Carlos Cavalcanti, 4748, ZIP 84030-900, Ponta Grossa, PR (Brazil); Lacerda, Luiz Gustavo; Filho, Marco Aurelio Silva Carvalho [Positivo University, Curitiba, PR (Brazil); Bannach, Gilbert [Paulista State University - UNESP, Bauru, SP (Brazil); Schnitzler, Egon, E-mail: egons@uepg.br [State University of Ponta Grossa - UEPG, Av. Carlos Cavalcanti, 4748, ZIP 84030-900, Ponta Grossa, PR (Brazil)

    2013-01-20

    Highlights: Black-Right-Pointing-Pointer Untreated cassava starch was modified with standard hydrochloric acid at 20 and 50 Degree-Sign C by 8 h. Black-Right-Pointing-Pointer DSC curves allowed to verify increase in the gelatinization enthalpy in agreement with high temperature. Black-Right-Pointing-Pointer Pasting properties of the studied starches were inversely proportional to the acid treatment and increased temperature. Black-Right-Pointing-Pointer The morphology of granules as well as average size and average roughness were calculated by NC-AFM. - Abstract: Starch is arguably one of the most actively investigated biopolymer in the world. In this study, the native (untreated) cassava starch granules (Manihot esculenta, Crantz) were hydrolyzed by standard hydrochloric acid solution at different temperatures (30 Degree-Sign C and 50 Degree-Sign C) and the hydrolytic transformations were investigated by the following techniques: simultaneous thermogravimetry-differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), as well as non-contact atomic force microscopy (NC-AFM), X-ray diffraction (XRD) powder patterns, and rapid viscoamylographic analysis (RVA). After the treatment with hydrochloric acid at different temperatures, the thermal stability, a gradual loss of pasting properties (viscosity), alterations in the gelatinization enthalpy ({Delta}H{sub gel}), were observed. The use of NC-AFM and XRD allowed the observation of the surface morphology and topography of the starch granules and changes in crystallinity of the granules, respectively.

  11. Bi-functional biobased packing of the cassava starch, glycerol, licuri nanocellulose and red propolis.

    Directory of Open Access Journals (Sweden)

    Samantha Serra Costa

    Full Text Available The aim of this study was to characterize and determine the bi-functional efficacy of active packaging films produced with starch (4% and glycerol (1.0%, reinforced with cellulose nanocrystals (0-1% and activated with alcoholic extracts of red propolis (0.4 to 1.0%. The cellulose nanocrystals used in this study were extracted from licuri leaves. The films were characterized using moisture, water-activity analyses and water vapor-permeability tests and were tested regarding their total phenolic compounds and mechanical properties. The antimicrobial and antioxidant efficacy of the films were evaluated by monitoring the use of the active films for packaging cheese curds and butter, respectively. The cellulose nanocrystals increased the mechanical strength of the films and reduced the water permeability and water activity. The active film had an antimicrobial effect on coagulase-positive staphylococci in cheese curds and reduced the oxidation of butter during storage.

  12. Bi-functional biobased packing of the cassava starch, glycerol, licuri nanocellulose and red propolis.

    Science.gov (United States)

    Costa, Samantha Serra; Druzian, Janice Izabel; Machado, Bruna Aparecida Souza; de Souza, Carolina Oliveira; Guimarães, Alaíse Gil

    2014-01-01

    The aim of this study was to characterize and determine the bi-functional efficacy of active packaging films produced with starch (4%) and glycerol (1.0%), reinforced with cellulose nanocrystals (0-1%) and activated with alcoholic extracts of red propolis (0.4 to 1.0%). The cellulose nanocrystals used in this study were extracted from licuri leaves. The films were characterized using moisture, water-activity analyses and water vapor-permeability tests and were tested regarding their total phenolic compounds and mechanical properties. The antimicrobial and antioxidant efficacy of the films were evaluated by monitoring the use of the active films for packaging cheese curds and butter, respectively. The cellulose nanocrystals increased the mechanical strength of the films and reduced the water permeability and water activity. The active film had an antimicrobial effect on coagulase-positive staphylococci in cheese curds and reduced the oxidation of butter during storage.

  13. Swelling properties of cassava starch grafted with poly (potassium acrylate-co-acrylamide) superabsorbent hydrogel prepared by ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Barleany, Dhena Ria, E-mail: dbarleany@yahoo.com; Ulfiyani, Fida; Istiqomah, Shafina; Rahmayetty [Department of Chemical Engineering, University of Sultan Ageng Tirtayasa, Cilegon, Banten (Indonesia); Heriyanto, Heri; Erizal [Centre for Application of Isotopes and Radiation, Jakarta (Indonesia)

    2015-12-29

    Natural and synthetic hydrophylic polymers can be phisically or chemically cross-linked in order to produce hydrogels. Starch based hydrogels grafted with copolymers from acrylic acid or acrylamide have become very popular for water absorbent application. Superabsorbent hydrogels made from Cassava starch grafted with poly (potassium acrylate-co-acrylamide) were prepared by using of ϒ-irradiation method. Various important parameters such as irradiation doses, monomer to Cassava starch ratio and acrylamide content were investigated. The addition of 7,5 % w w{sup −1} acrylamide into the reaction mixture generated a starch graft copolymer with a water absorption in distilled water as high as 460 g g{sup −1} of its dried weight. The effectivity of hydrogel as superabsorbent for aqueous solutions of NaCl and urea was evaluated. The obtained hydrogel showed the maximum absorptions of 317 g g{sup −1} and 523 g g{sup −1} for NaCl and urea solution, respectively (relative to its own dry weight). The structure of the graft copolymer was analyzed by using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM)

  14. Swelling properties of cassava starch grafted with poly (potassium acrylate-co-acrylamide) superabsorbent hydrogel prepared by ionizing radiation

    Science.gov (United States)

    Barleany, Dhena Ria; Ulfiyani, Fida; Istiqomah, Shafina; Heriyanto, Heri; Rahmayetty, Erizal

    2015-12-01

    Natural and synthetic hydrophylic polymers can be phisically or chemically cross-linked in order to produce hydrogels. Starch based hydrogels grafted with copolymers from acrylic acid or acrylamide have become very popular for water absorbent application. Superabsorbent hydrogels made from Cassava starch grafted with poly (potassium acrylate-co-acrylamide) were prepared by using of ϒ-irradiation method. Various important parameters such as irradiation doses, monomer to Cassava starch ratio and acrylamide content were investigated. The addition of 7,5 % w w-1 acrylamide into the reaction mixture generated a starch graft copolymer with a water absorption in distilled water as high as 460 g g-1 of its dried weight. The effectivity of hydrogel as superabsorbent for aqueous solutions of NaCl and urea was evaluated. The obtained hydrogel showed the maximum absorptions of 317 g g-1 and 523 g g-1 for NaCl and urea solution, respectively (relative to its own dry weight). The structure of the graft copolymer was analyzed by using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM).

  15. Effects of Ultrasound on Crystallization of Cassava Starch%超声波作用对木薯淀粉颗粒结晶的影响

    Institute of Scientific and Technical Information of China (English)

    蓝丽红; 李冬雪; 陈阿明; 封余贤; 蓝平; 廖安平

    2012-01-01

    [目的]为了研究超声波作用对木薯淀粉结结晶结构的影响.[方法]用偏光显微镜对超声波作用后的木薯淀粉进行表征.[结果]超声波处理木薯淀粉的最佳条件为:以浓度5%硫酸钠溶液为溶剂,木薯淀粉悬浮液中淀粉含量为16.7%,功率为400W,作用时间300s.经超声作用的木薯淀粉颗粒的偏光十字特征减弱或消失,木薯淀粉颗粒的结晶结构减弱或消失.[结论]超声作用破坏了淀粉的结晶结构,颗粒表面与反应试剂的接触面积增多,从而提高了反应活性.%[Objective] The research aimed to study the effects of ultrasound on the particle shape of cassava starch. [ Method ] Polarizing microscope was used to study cassava starch treated by ultrasound. [Result] The optimum ultrasonic treatment of cassava starch was as follows: 5% sodium sulfate as solvent, content of cassava starch 16.7% , ultrasonic power 400 W and lmdation time 300 s. The cross-polarized state of cassava starch granules showed weakening or disappearance and cassava starch granules crystal structure reduced or lost. [ Conclusion] Ultrasonic ir-ridation destroyed the crystalline structure of starch, and increased its contact area of particle surface and reactivity.

  16. Thermoplastic starch/polyester films: effects of extrusion process and poly (lactic acid) addition.

    Science.gov (United States)

    Shirai, Marianne Ayumi; Olivato, Juliana Bonametti; Garcia, Patrícia Salomão; Müller, Carmen Maria Olivera; Grossmann, Maria Victória Eiras; Yamashita, Fabio

    2013-10-01

    Biodegradable films were produced using the blown extrusion method from blends that contained cassava thermoplastic starch (TPS), poly(butylene adipate-co-terephthalate) (PBAT) and poly(lactic acid) (PLA) with two different extrusion processes. The choice of extrusion process did not have a significant effect on the mechanical properties, water vapor permeability (WVP) or viscoelasticity of the films, but the addition of PLA decreased the elongation, blow-up ratio (BUR) and opacity and increased the elastic modulus, tensile strength and viscoelastic parameters of the films. The films with 20% PLA exhibited a lower WVP due to the hydrophobic nature of this polymer. Morphological analyses revealed the incompatibility between the polymers used.

  17. Effect of resistant starch on the cooking quality of yam (Dioscorea spp.) and cassava (Manihot esculenta) based paste products.

    Science.gov (United States)

    Kouadio, Olivier Kouadio; N'dri, Denis Yao; Nindjin, Charlemagne; Marti, Alessandra; Casiraghi, Maria Cristina; Faoro, Franco; Erba, Daniela; Bonfoh, Bassirou; Amani, N'guessan Georges

    2013-06-01

    Total starch (TS) and resistant starch (RS) contents in pasty edible product of mealy and hard cooking tubers of three yam varieties and four cassava varieties were determined to evaluate their contribution in their cooking quality. TS and RS contents appeared as the main components in determining yam cooking quality. Mealy cooking yam varieties were characterized by a significant higher TS content (75.2 ± 7.7 g/100 g d.m.) and lower RS content (13.8 ± 3.4 g/100 g d.m.) than hard cooking yam varieties, which, in contrast, contained less TS (61.7 ± 12.1 g/100 g d.m.) and particularly high RS (21.8 ± 9.9 g/100 g d.m.), possibly as a consequence of the prevalence of large granules (35-40 μm) observed by light microscope. Conversely, TS and RS contents appeared not determinant on the cooking quality of cassava. Moreover, higher amylose contents were associated with substantially elevated percentages of RS in yam and cassava, and high RS content in samples modulates their pasting properties by reducing the peak viscosity and the breakdown and requiring higher temperature and longer time to the peak.

  18. Uso de fécula de mandioca na pó-colheita de manga 'surpresa' Use of cassava starch in the 'surpresa' mango postharvest

    Directory of Open Access Journals (Sweden)

    Laerte Scanavaca Júnior

    2007-04-01

    Full Text Available A manga é uma fruta tropical climatéria que amadurece rapidamente depois de colhida. Avaliou-se a vida útil pós-colheita de mangas 'Surpresa' utilizando recobrimento com película de fécula de mandioca. Os frutos foram mergulhados em suspensões a 0; 1; 2 e 3% de fécula de mandioca por três minutos, secos ao ar e armazenados em temperatura ambiente (± 29º C e ± 87% de umidade relativa. O delineamento utilizado foi o inteiramente casualizado, em fatorial de 4 x 5 (tratamentos x tempo. Foram avaliados a perda de massa fresca (%, a firmeza do fruto e da polpa, a acidez total titulável, os sólidos solúveis totais, a relação SST/ATT e o pH, além das cores da casca e da polpa. Os frutos foram avaliados aos 0; 3; 6; 9 e 12 dias. Os frutos tratados com 3% de fécula de mandioca reduziram a perda de água e melhoraram o aspecto visual dos frutos, e a logevidade deste tratamento foi de 12 contra 7 dias da testemunha.The mango is a tropical climacteric fruit that ripens quickly after having been picked. The useful postharvest life of 'Surpresa' mangos was evaluated using covering with cassava starch film. The fruits were immersed in suspensions to 1, 2 and 3% of cassava starch for three minutes, dried by the air and conserved in ambient temperature at ± 29º C of temperature and ± 87% of relative humidity. The outline used was entirely randomized and the experiment was carried out in 4 x 5 fatorial design (treatments x time. The loss of fresh mass (%, the firmness of the fruit and pulp, the total titratable acidity (TTA, the total soluble solids (TSS, the TSS/TTA relation and the pH, were evaluated besides of the colors of the peel and pulp. The fruits were evaluated on the 0, 3, 6, 9 and 12 days. The fruits treated with 3% of cassava starch reduced its loses of water and improved the visual aspect of the fruits, and the shelf life of this treatment was 12 against 7 days of the witness.

  19. 酸解木薯淀粉及其软糖性能研究%Study on properties of acid hydrolysis cassava starch and its jelly candy

    Institute of Scientific and Technical Information of China (English)

    范浩然; 熊柳; 孙庆杰

    2013-01-01

    The acid hydrolysis of cassava starches were prepared using cassava starch as material, treating starch with 6%HCl at 50℃for different durations(0 min,30 min,60 min,90 min). At the same time the acid hydrolysis of cassava starches were used to produce cassava starch jelly candy. The properties of the acid hydrolysis of cassava starch were investigated by determining the gelatinization and texture properties and assay the tensile properties and texture properties of the acid hydrolysis cassava starch jelly candy. The results showed that a significant decrease in starch viscosity and set back and an increase in hardness with increase in acid hydrolysis. The tensile properties of jelly candy with three different hydrolysis time all accord with industrial production index. The jelly candy with 60 min acid hydrolysis of cassava starch was better on hardness,adhesiveness,chewiness and resilience.%  以木薯淀粉为原料,在50℃下,用6%HCl对木薯淀粉进行不同时间(0 min、30 min、60 min、90 min)酸解改性,制备酸解木薯淀粉,并对酸解淀粉糊化特性和质构特性进行研究与分析;同时采用酸解木薯淀粉制备软糖,对制得酸解木薯淀粉软糖进行拉伸与质构分析.实验结果表明,随酸解时间增加;酸解木薯淀粉最低粘度、峰值粘度、回生值显著降低,淀粉凝胶硬度显著增加.3个不同水解时间木薯软糖拉伸率均符合工业生产指标,60 min酸解木薯淀粉制备软糖硬度适中,胶粘性、咀嚼性、回复性良好.

  20. Acidification and starch behaviour during co-fermentation of cassava (Manihot esculenta Crantz) and soybean (Glycine max Merr) into gari, an African fermented food.

    Science.gov (United States)

    Afoakwa, Emmanuel Ohene; Kongor, Edem John; Annor, George Amponsah; Adjonu, Randy

    2010-08-01

    Changes in acidification and starch behaviour were investigated during co-fermentation of cassava and soybean into gari, an African fermented product. Non-volatile acidity, pH and starch content were evaluated using standard analytical methods. Starch breakdown and pasting characteristics were also analysed using a Brabender viscoamylograph. Fermentation caused significant variations in the pH, non-volatile acidity and starch concentration. The pH decreased with concomitant increases in non-volatile acidity during co-fermentation of the cassava dough. Soy fortification up to 20% caused only minimal effects on the pH, titratable acidity and starch content during the fermentation period. Starch content decreased from 69.8% to 60.4% within the 48 h fermentation time in the unfortified sample, with similar trends noted at all levels of fortification. Starch pasting characteristics showed varied trends in pasting temperature, peak viscosity, viscosity at 95 degrees C and at 50 degrees C-hold with increasing fermentation time and soybean concentration. Cassava could be co-fermented with soybean up to 20% concentration during gari processing without significant effect on its process and product quality characteristics.

  1. Effect of gamma irradiation on thermophysical properties of plasticized starch and starch surfactant films

    Science.gov (United States)

    Cieśla, Krystyna; Watzeels, Nick; Rahier, Hubert

    2014-06-01

    In this work the influence of gamma irradiation on the thermomechanical properties of the films formed in potato starch-glycerol and potato starch-glycerol-surfactant systems were examined by Dynamic Mechanical Analysis, DMA, and Differential Scanning Calorimetry, DSC, and the results were correlated to the amount of the volatile fraction in the films.

  2. Isolation and characterization of two soil derived yeasts for bioethanol production on Cassava starch

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Gi-Wook; Kim, Yule; Kang, Hyun-Woo [Changhae Institute of Cassava and Ethanol Research, Changhae Ethanol Co., Ltd, Palbok-Dong 829, Dukjin-Gu, Jeonju 561-203 (Korea); Um, Hyun-Ju; Kim, Mina; Kim, Yang-Hoon [Department of Microbiology, Chungbuk National University, 410 Sungbong-Ro, Heungduk-Gu, Cheongju 361-763 (Korea); Chung, Bong-Woo [Department of Bioprocess Engineering, Chonbuk National University, 664-14, 1-Ga, Duckjin-Dong, Duckjin-Gu, Jeonju 561-156 (Korea)

    2010-08-15

    Two ethanol-producing yeast strains, CHY1011 and CHFY0901 were isolated from soil in South Korea using an enrichment technique in a yeast peptone dextrose medium supplemented with 5% (w v{sup -1}) ethanol at 30 C. The phenotypic and physiological characteristics, as well as molecular phylogenetic analysis based on the D1/D2 domains of the large subunit (26S) rRNA gene and the internally transcribed spacer (ITS) 1 + 2 regions suggested that they were novel strains of Saccharomyces cerevisiae. During shaking flask cultivation, the highest ethanol productivity and theoretical yield of S. cerevisiae CHY1011 in YPD media containing 9.5% total sugars was 1.06 {+-} 0.02 g l{sup -1} h{sup -1} and 95.5 {+-} 1.2%, respectively, while those for S. cerevisiae CHFY0901 were 0.97 {+-} 0.03 g l{sup -1} h{sup -1} and 91.81 {+-} 2.2%, respectively. Simultaneous saccharification and fermentation for ethanol production was carried out using liquefied cassava (Manihot esculenta) starch in a 5 l lab-scale jar fermenter at 32 C for 66 h with an agitation speed of 2 Hz. Under these conditions, S. cerevisiae CHY1011 and CHFY0901 yielded a final ethanol concentration of 89.1 {+-} 0.87 g l{sup -1} and 83.8 {+-} 1.11 g l{sup -1}, a maximum ethanol productivity of 2.10 {+-} 0.02 g l{sup -1} h{sup -1} and 1.88 {+-} 0.01 g l{sup -1} h{sup -1}, and a theoretical yield of 93.5 {+-} 1.4% and 91.3 {+-} 1.1%, respectively. These results suggest that S. cerevisiae CHY1011 and CHFY0901 have potential use in industrial bioethanol fermentation processes. (author)

  3. Isolation and characterisation of starch biosynthesis genes from cassava (Manihot esculenta Crantz).

    NARCIS (Netherlands)

    Munyikwa, T.R.I.

    1997-01-01

    Cassava (Manihot esculenta Crantz) is a tropical crop grown for its starchy thickened roots, mainly by peasant farmers, in the tropics, for whom it is a staple food. There is an increasing demand for the use of cassava in processed food and feed products, and in the paper and textile industries amon

  4. Biocomposite of Cassava Starch Reinforced with Cellulose Pulp Fibers Modified with Deposition of Silica (SiO2 Nanoparticles

    Directory of Open Access Journals (Sweden)

    Joabel Raabe

    2015-01-01

    Full Text Available Eucalyptus pulp cellulose fibers were modified by the sol-gel process for SiO2 superficial deposition and used as reinforcement of thermoplastic starch (TPS. Cassava starch, glycerol, and water were added at the proportion of 60/26/14, respectively. For composites, 5% and 10% (by weight of modified and unmodified pulp fibers were added before extrusion. The matrix and composites were submitted to thermal stability, tensile strength, moisture adsorption, and SEM analysis. Micrographs of the modified fibers revealed the presence of SiO2 nanoparticles on fiber surface. The addition of modified fibers improved tensile strength in 183% in relation to matrix, while moisture adsorption decreased 8.3%. Such improvements were even more effective with unmodified fibers addition. This result was mainly attributed to poor interaction between modified fibers and TPS matrix detected by SEM analysis.

  5. Amylase production by Saccharomycopsis fibuligera A11 in solid-state fermentation for hydrolysis of Cassava starch.

    Science.gov (United States)

    Chen, Lei; Chi, Zhen-Ming; Chi, Zhe; Li, Mei

    2010-09-01

    The optimization of process parameters for high amylase production by Saccharomycopsis fibuligera A11 in solid-state fermentation was carried out using central composite design. Finally, the optimal parameters obtained with the response surface methodology (RSM) were moisture 610.0 ml/kg, inoculum 30.0 ml (OD(600 nm) = 20.0)/kg, the amount ratio of wheat bran to rice husk 0.42, cassava starch concentration 20.0 g/kg, temperature 28 degrees C, and natural pH. Under the optimized conditions, 4,296 U/g of dry substrate of amylase activity was reached in the solid-state fermentation culture of the yeast strain A11 within 160 h, whereas the predicted maximum amylase activity of 4,222 U/g of dry substrate of amylase activity was derived from the RSM regression. It was found that cassava starch can be actively converted into monosaccharides and oligosaccharides by the crude amylase.

  6. 机械活化木薯淀粉的光谱分析%Spectrum Analysis of Mechanical Activated Cassava Starch

    Institute of Scientific and Technical Information of China (English)

    孙丹丹; 张宏伟

    2012-01-01

    采用机械活化的方法对木薯淀粉进行处理,利用X射线衍射、红外光谱及激光光谱等方法对处理后木薯淀粉的结晶结构、分子基团和粒径分布进行分析。研究结果表明,机械活化可以有效降低木薯淀粉颗粒的粒径,且粒径线性回归的趋势分布随活化时间不同而迁移,机械活化能破坏木薯淀粉的结晶结构,在X射线衍射图上表现为结晶衍射峰消失,机械活化可以增加木薯淀粉中反应基团游离羟基的数量,尤其使伯羟基的数量增加。%Cassava starch was processed by mechanical activation.Crystal structure,molecular group and particle size distribution of processed cassava starch were studied by X-ray diffraction,infrared spectroscopy and laser spectroscopy.The results showed that particle size of cassava starch could be reduced effectively by mechanical activation,and distribution of its linear regression trend was shifted with different activation time.Mechanical activation energy could destroy crystal structure of cassava starch,shown as disappearance of crystal diffraction peak in the X-ray diffraction diagram.And mechanical activation could increase the number of reactive free hydroxyl of cassava starch,especially primary hydroxyl.

  7. Effect of thermal and chemical modifications on the mechanical and release properties of paracetamol tablet formulations containing corn, cassava and sweet potato starches as filler-binders

    Institute of Scientific and Technical Information of China (English)

    Mariam; Vbamiunomhene; Lawal; Michael; Ayodele; Odeniyi; Oludele; Adelanwa; Itiola

    2015-01-01

    Objective: To investigate the effects of acetylation and pregelatinization of cassava and sweet potato starches on the mechanical and release properties of directly compressed paracetamol tablet formulations in comparison with official corn starch.Methods: The native starches were modified by acetylation and pregelatinization. The tablets were assessed using friability(Fr), crushing strength(Cs), disintegration time(Dt) and dissolution parameters. Results: Starch acetylation produced paracetamol tablets that were stronger and had the best balance of mechanical and disintegration properties, while pregelatinization produced tablets that were more friable but had a better overall strength in relation to disintegration than formulations made from natural starches. Correlations mainly existed between Dt and the dissolution parameters t80, t2 and k1 in the formulations. Conclusions: Modification of the experimental starches improved the mechanical and release properties of directly compressed paracetamol tablet formulations. Thus, they can be developed for use as pharmaceutical excipients in specific formulations.

  8. Effect of thermal and chemical modiifcations on the mechanical and release properties of paracetamol tablet formulations containing corn, cassava and sweet potato starches as ifller-binders

    Institute of Scientific and Technical Information of China (English)

    Mariam Vbamiunomhene Lawal; Michael Ayodele Odeniyi; Oludele Adelanwa Itiola

    2015-01-01

    Objective:To investigate the effects of acetylation and pregelatinization of cassava and sweet potato starches on the mechanical and release properties of directly compressed paracetamol tablet formulations in comparison with official corn starch. Methods: The native starches were modified by acetylation and pregelatinization. The tablets were assessed using friability (Fr), crushing strength (Cs), disintegration time (Dt) and dissolution parameters. Results: Starch acetylation produced paracetamol tablets that were stronger and had the best balance of mechanical and disintegration properties, while pregelatinization produced tablets that were more friable but had a better overall strength in relation to disintegration than formulations made from natural starches. Correlations mainly existed between Dt and the dissolution parameters t80, t2 and k1 in the formulations. Conclusions:Modification of the experimental starches improved the mechanical and release properties of directly compressed paracetamol tablet formulations. Thus, they can be developed for use as pharmaceutical excipients in specific formulations.

  9. Starch/polyester films: simultaneous optimisation of the properties for the production of biodegradable plastic bags

    Directory of Open Access Journals (Sweden)

    J. B. Olivato

    2013-01-01

    Full Text Available Blends of starch/polyester have been of great interest in the development of biodegradable packaging. A method based on multiple responses optimisation (Desirability was used to evaluate the properties of tensile strength, perforation force, elongation and seal strength of cassava starch/poly(butylene adipate-co-terephthalate (PBAT blown films produced via a one-step reactive extrusion using tartaric acid (TA as a compatibiliser. Maximum results for all the properties were set as more desirable, with an optimal formulation being obtained which contained (55:45 starch/PBAT (88.2 wt. (%, glycerol (11.0 wt. (% and TA (0.8 wt. (%. Biodegradable plastic bags were produced using the film with this formulation, and analysed according to the standard method of the Associação Brasileira de Normas Técnicas (ABNT. The bags exhibited a 45% failure rate in free-falling dart impact tests, a 10% of failure rate in dynamic load tests and no failure in static load tests. These results meet the specifications set by the standard. Thus, the biodegradable plastic bags fabricated with an optimised formulation could be useful as an alternative to those made from non-biodegradable materials if the nominal capacity declared for this material is considered.

  10. Development of oxidised and heat-moisture treated potato starch film.

    Science.gov (United States)

    Zavareze, Elessandra da Rosa; Pinto, Vânia Zanella; Klein, Bruna; El Halal, Shanise Lisie Mello; Elias, Moacir Cardoso; Prentice-Hernández, Carlos; Dias, Alvaro Renato Guerra

    2012-05-01

    This study investigated the effects of sodium hypochlorite oxidation and a heat-moisture treatment of potato starch on the physicochemical, pasting and textural properties of potato starches in addition to the water vapour permeability (WVP) and mechanical properties of potato starch films produced from these starches. The carbonyl contents, carboxyl contents, swelling power, solubility, pasting properties and gel texture of the native, oxidised and heat-moisture treated (HMT) starches were evaluated. The films made of native, oxidised and HMT starches were characterised by thickness, water solubility, colour, opacity, mechanical properties and WVP. The oxidised and HMT starches had lower viscosity and swelling power compared to the native starch. The films produced from oxidised potato starch had decreased solubility, elongation and WVP values in addition to increased tensile strength compared to the native starch films. The HMT starch increased the tensile strength and WVP of the starch films compared to the native starch.

  11. Phylogeny and expression pattern of starch branching enzyme family genes in cassava (Manihot esculenta Crantz) under diverse environments.

    Science.gov (United States)

    Pei, Jinli; Wang, Huijun; Xia, Zhiqiang; Liu, Chen; Chen, Xin; Ma, Pingan; Lu, Cheng; Wang, Wenquan

    2015-08-01

    Starch branching enzyme (SBE) is one of the key enzymes involved in starch biosynthetic metabolism. In this study, six SBE family genes were identified from the cassava genome. Phylogenetic analysis divided the MeSBE family genes into dicot family A, B, C, and the new group. Tissue-specific analysis showed that MeSBE2.2 was strongly expressed in leaves, stems cortex, and root stele, and MeSBE3 had high expression levels in stem cortex and root stele of plants in the rapid growth stage under field condition, whereas the expression levels of MeSBE2.1, MeSBE4, and MeSBE5 were low except for in stems cortex. The transcriptional activity of MeSBE2.2 and MeSBE3 was higher compared with other members and gradually increased in the storage roots during root growth process, while the other MeSBE members normally remained low expression levels. Expression of MeSBE2.2 could be induced by salt, drought, exogenous abscisic acid, jasmonic acid, and salicylic acid signals, while MeSBE3 had positive response to drought, salt, exogenous abscisic acid, and salicylic acid in leaves but not in storage root, indicating that they might be more important in starch biosynthesis pathway under diverse environments.

  12. Research on the Physicochemical Property of the Starch in Different Cassava Varieties%不同品种的木薯淀粉理化特性研究

    Institute of Scientific and Technical Information of China (English)

    杨栋林; 陈燕珍; 庞月圆; 刘晓灿; 谭涛

    2009-01-01

    [Objective] The physical and chemical characteristics of cassava starch was studied.[Method] The cassava variety: bread cassava with large leaf and white skin(DB), bread cassava with small leaf and white skin (XB), bread cassava with large leaf and red skin(DH) being taken as experimental material, the physical and chemical property such as the content of protein, the light transmittance, the stability of frozen and condensation/precipitation, and cassava shape of these varieties was tested.[Results] The order of the content of protein from high to low was: XB>DH>DB;the light transmittance, DB>XB>DH;there was no difference in the stability of frozen and condensation/precipitation among varieties;and there was difference in the cassava shape among varieties.[Conclusion] The scientific reference for the deep processing and development and utilization of cassava was provided.%[目的]研究木薯淀粉的理化特性.[方法]以大叶白皮面包木薯(DB)、小叶白皮面包木薯(XB)、大叶红皮面包木薯(DH)为试验材料,测定其蛋白质含量、透光率、冷冻稳定性、凝沉稳定性及颗粒形态等理化特性.[结果]蛋白质含量的高低为:XB>DH>DB;透光率的大小为:DB>XB>DH;冷冻稳定性及凝沉稳定性差异不大;淀粉的颗粒形态有差异.[结论]试验为木薯的深加工及开发利用提供了科学的参考依据.

  13. Production of raw starch-degrading enzyme by Aspergillus sp. and its use in conversion of inedible wild cassava flour to bioethanol.

    Science.gov (United States)

    Moshi, Anselm P; Hosea, Ken M M; Elisante, Emrode; Mamo, Gashaw; Önnby, Linda; Nges, Ivo Achu

    2016-04-01

    The major bottlenecks in achieving competitive bioethanol fuel are the high cost of feedstock, energy and enzymes employed in pretreatment prior to fermentation. Lignocellulosic biomass has been proposed as an alternative feedstock, but because of its complexity, economic viability is yet to be realized. Therefore, research around non-conventional feedstocks and deployment of bioconversion approaches that downsize the cost of energy and enzymes is justified. In this study, a non-conventional feedstock, inedible wild cassava was used for bioethanol production. Bioconversion of raw starch from the wild cassava to bioethanol at low temperature was investigated using both a co-culture of Aspergillus sp. and Saccharomyces cerevisiae, and a monoculture of the later with enzyme preparation from the former. A newly isolated strain of Aspergillus sp. MZA-3 produced raw starch-degrading enzyme which displayed highest activity of 3.3 U/mL towards raw starch from wild cassava at 50°C, pH 5.5. A co-culture of MZA-3 and S. cerevisiae; and a monoculture of S. cerevisiae and MZA-3 enzyme (both supplemented with glucoamylase) resulted into bioethanol yield (percentage of the theoretical yield) of 91 and 95 at efficiency (percentage) of 84 and 96, respectively. Direct bioconversion of raw starch to bioethanol was achieved at 30°C through the co-culture approach. This could be attractive since it may significantly downsize energy expenses.

  14. Study on Preparation and Properties of Cross-Linking and Esterifying Starch of Mechanical Activated Cassava Starch%机械活化木薯交联酯化淀粉的制备及其性能研究

    Institute of Scientific and Technical Information of China (English)

    陈渊; 杨家添; 谢祖芳; 谭义秋; 黄祖强; 周琴

    2012-01-01

    Cross - linking and esterifying starch of mechanical activated cassava starch was prepared by using mechanical activated cassava starch as raw material, and using sodium trimetaphosophate for cross - linking agent and acetic anhydride for acetification, which its synthesis route prepared by continual reactions in one - step synthesis way. The effects of reaction temerature, cross - linking agent and esterifying agent dosage, pH value of cross — linking and esterifying and cross - linking time on the cold viscosity of cross - linking and esterifying starch paste were investigated respectively, and the physical and chemical Parameters and structure of the cross - linking and esterifying starch with mechanical activated cassava starch and cross - linking and esterifying starch with raw cassava starch were studied. The results indicated that the above reaction conditions were all found to affect the preparation of cross - linking and esterifying mechanical activated cassava starch. Under the reaction temperature 40℃ ,1.0% amounts of sodium trimetaphosphate,crosslinking pH value 10.0,crosslinking time 2. 0 h,acetic anhydride amount 0. 5 mL,esterifying pH value 9.0, esterifying time 60 min, the cold viscosity of cross - linking and esterifying starch paste of mechanical activated cassava was enhanced from 847 mPa. S of cassava starch to 3 225 mPa. S, and the stability, acidity - resistance, staling resistance of the viscosity of starch paste were significantly improved. Cross - linking and esterifying composite modified was propitious to formation of V type crystal starch.%以机械活化木薯淀粉为原料,三偏磷酸钠为交联剂,醋酸酐为酯化剂,采用一步连续法制备机械活化木薯交联酯化淀粉,考察反应温度、交联剂用量、交联pH、交联时间、酯化剂用量、酯化pH、酯化时间等因素对交联酯化淀粉糊冷黏度的影响,并与原木薯淀粉合成的交联酯化淀粉进行比较,研究了产物的理化特性

  15. Characterization of foams obtained from cassava starch, cellulose fibres and dolomitic limestone by a thermopressing process

    Directory of Open Access Journals (Sweden)

    Vivian Consuelo Reolon Schmidt

    2010-02-01

    Full Text Available Cassava starch, dolomitic limestone and eucalypt cellulose fibres were used to prepare foam trays that could be used to pack foodstuffs. The influence of the cellulose fibre concentration in the composite formulation was investigated using 5, 10, 15, 20, 30 and 40% of fibres. The results indicated that an increase in cellulose fibre concentration promoted a decrease in density and tensile strength of the foam samples. The tensile strength at break for foam trays containing 5% of cellulose fibres was 3.03MPa, whilst the commercial trays of expanded polystyrene used to pack foods in supermarkets presented a tensile strength of 1.49 MPa. The elongation at break of the foam trays obtained in this work varied slightly with increase in cellulose fibre concentration, the values being about 20% lower than the elongation at break observed for commercial foam trays of expanded polystyrene. Thus, the materials developed in this work represented a possible alternative to the use of EPS foam trays for packing dry foods. The trays' properties need to be improved for their use with moist foods.Amido de mandioca, calcário dolomítico e fibras celulósicas de eucalipto foram usados para preparar bandejas biodegradáveis que podem ser usadas como embalagens para alimentos. A influência da concentração de fibras na formulação dos compostos foi investigada, usando 5, 10, 15, 20, 30 e 40% de fibras. Os resultados indicaram que o aumento na concentração de fibras celulósicas promove uma diminuição na densidade e na resistência a tração das amostras. A tensão na ruptura para as bandejas contendo 5% de fibras celulósicas foi de 3,03 MPa, enquanto as bandejas comerciais de poliestireno expandido (EPS usadas para embalagens alimentícias em supermercados apresentaram uma tensão de 1.49 MPa. A elongação na ruptura das bandejas obtidas neste trabalho variou ligeiramente com o aumento da concentração de fibra celulósica, os valores são aproximadamente

  16. Response surface optimisation for acetone-butanol-ethanol production from cassava starch by co-culture of Clostridium butylicum and Bacillus subtilis

    Directory of Open Access Journals (Sweden)

    Benjamas Cheirsilp

    2011-11-01

    Full Text Available Acetone-butanol-ethanol (ABE production from cassava starch was enhanced by a syntrophic co-culture of Clostridium butylicum TISTR 1032 and high amylase producing Bacillus subtilis WD 161 without anaerobic pretreatment. The production of amylase and ABE using this co-culture were respectively 16 and 6 times higher than those using the pure culture of C. butylicum TISTR 1032. The effect of the medium components on the performance of the co-culture was investigated using response surface methodology (RSM. Among the investigated components, cassava starch and ammonium nitrate contributed a significant effect on the production of amylase and ABE, while yeast extract had less effect. Based on the optimum strategy using RSM, the ABE production by the co-culture was improved 2.2-fold compared with that obtained from the initial condition and with a minimum requirement of nitrogen source.

  17. Cassava starch graft copolymers an eco-friendly corrosion inhibitor for steel in H{sub 2}SO{sub 4} solution

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xianghong; Deng, Shuduan [Southwest Forestry University, Kunming (China)

    2015-11-15

    Cassava starch graft copolymer (CSGC) was prepared by grafting acryl amide (AA) onto cassava starch (CS). The inhibition effect of CSGC on the corrosion of cold rolled steel (CRS) in 1.0M H{sub 2}SO{sub 4} solution was first studied by weight loss, potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS) and scanning electron microscope (SEM) methods. The results show that CSGC is a good inhibitor, and inhibition efficiency of CSGC is higher than that of CS or AA. The adsorption of CSGC on steel surface obeys Langmuir adsorption isotherm. CSGC is a mixed-type inhibitor at 20 .deg. C, while mainly a cathodic inhibitor at 50 .deg. C.

  18. Experimental Researches on Cassava Starch Wastewater Treatment by Coagulation Sedimentation%絮凝法处理木薯淀粉生产废水试验研究

    Institute of Scientific and Technical Information of China (English)

    王汉林; 刘康怀

    2013-01-01

    Cassava starch wastewater from the processing industry has brought great environmental pollutions . Some experimental researches on cassava starch wastewater treatment were done by coagulation sedimenta-tion.In the experiments three flocculants were used which were:polyferrum,polymeric aluminum and sulfra aliminium,and polyacrylamide was used as concretion -aid agant.Through the analysis of experimental da-tas,the result was obtained that the best conditions of cassava starch wastewater treatment were as follows:pH-7.5,flocculant-polymeric aluminum,concretion-aid agant-polyacrylamide.In this way the cost of cas-sava starch wastewater treatment was only 0.14 yuan per ton.%  木薯淀粉生产加工过程中所产生的生产废水给环境造成了很大的污染。对木薯淀粉生产废水进行了絮凝试验研究。试验分别采用了3种絮凝剂:聚合硫酸铁、聚合氯化铝、精制硫酸铝,助凝剂采用聚丙烯酰胺。通过对试验数据进行分析得出,处理木薯淀粉生产废水的最佳条件是:pH 值为7.5,采用聚合氯化铝作絮凝剂,聚丙烯酰胺为助凝剂,处理每吨废水需花费0.14元。

  19. Partial characterization of chayotextle starch-based films added with ascorbic acid encapsulated in resistant starch.

    Science.gov (United States)

    Martínez-Ortiz, Miguel A; Vargas-Torres, Apolonio; Román-Gutiérrez, Alma D; Chavarría-Hernández, Norberto; Zamudio-Flores, Paul B; Meza-Nieto, Martín; Palma-Rodríguez, Heidi M

    2017-02-03

    Chayotextle starch was modified by subjecting it to a dual treatment with acid and heating-cooling cycles. This caused a decrease in the content of amylose, which showed values of 30.22%, 4.80%, 3.27% and 3.57% for native chayotextle starch (NCS), starch modified by acid hydrolysis (CMS), and CMS with one (CMS1AC) and three autoclave cycles (CMS3AC), respectively. The percentage of crystallinity showed an increase of 36.9%-62% for NCS and CMS3AC. The highest content of resistant starch (RS) was observed in CMS3AC (37.05%). The microcapsules were made with CMS3AC due to its higher RS content; the total content of ascorbic acid of the microcapsules was 82.3%. The addition of different concentrations of CMS3AC microcapsules (0%, 2.5%, 6.255% and 12.5%) to chayotextle starch-based films (CSF) increased their tensile strength and elastic modulus. The content of ascorbic acid and RS in CSF was ranged from 0% to 59.4% and from 4.84% to 37.05% in the control film and in the film mixed with CMS3AC microcapsules, respectively. Water vapor permeability (WVP) values decreased with increasing concentrations of microcapsules in the films. Microscopy observations showed that higher concentrations of microcapsules caused agglomerations due their poor distribution in the matrix of the films.

  20. Effects of Cassava Starch and Natural Rubber as Binders on the Flexural and Water Absorption Properties of Recycled Paper Pulp Based Composites

    Directory of Open Access Journals (Sweden)

    Oladele Isiaka Oluwole

    2015-10-01

    Full Text Available Responsiveness was given to the effects of cassava starch and natural rubber as binders on the flexural strength and the water absorptivity properties of the developed rattan particulate reinforced paper pulp based composites. Paper pulp was produced by chopping waste papers into smaller pieces and soaked in boiled water after which it was stirred thoroughly to form paper pulp. Rattan particulate was produced by hammering, chopping, pounding and milling of rattan canes followed by sieving into a particle size of 437 µ. Varying mass of paper from 300-400 g and particulate rattan in treated and untreated form of 2-8 g were mixed and bonded with natural rubber and cassava starch, respectively for the various samples developed. The mixtures were thoroughly mixed to produce homogenous pastes and poured into 150 x 50 x 30 mm detachable mould and compacted for 5 minutes using a laboratory compaction machine maintained at 20 KN. The developed composites were allowed to cure at room temperature for 27 days after which flexural and water absorptivity tests were carried out on the samples. It was noticed that the composite samples ST4 and S5 containing cassava starch happen to be the best in terms of flexural strength while NR2 gave the best water- repellent outcome.

  1. Water absorption, retention and the swelling characteristics of cassava starch grafted with polyacrylic acid

    NARCIS (Netherlands)

    Witono, J. R.; Noordergraaf, Inge; Heeres, H. J.; Janssen, L. P. B. M.; Heeres, Hero

    2014-01-01

    An important application of starch grafted with copolymers from unsaturated organic acids is the use as water absorbent. Although much research has been published in recent years, the kinetics of water absorption and the swelling behavior of starch based superabsorbents are relatively unexplored. Al

  2. Conversion of cassava starch to biomass, carbohydrates, and acids by Aspergillus niger.

    Science.gov (United States)

    Tan, K H; Ferguson, L B; Carlton, C

    1984-01-01

    The filamentous fungus, Aspergillus niger, efficiently converted cassava polysaccharides to mycelial mass, simple sugars, and acids during the course of its growth. A typical 70-ml culture broth containing 2% cassava polysaccharides yielded 0.38 g dry mycelial mass, 1.14 mmol reducing sugars, and 1.17 meq acids at the end of 42 h. About 70% of the initial total carbohydrate in the medium was degraded during the same period. The sugars and acids in the culture broths were analyzed by HPLC on a single Aminex HPX-87 column at 55 degrees C, using 0.013 N H2SO4 as the eluting solvent. Cassava polysaccharides were degraded to oligosaccharides, maltotriose, maltose, and glucose beyond the 20-h growth periods, with maltotriose emerging as the major simple sugar. The appearance of citric, malic, gluconic, succinic, and fumaric acids accounted mostly for the decreasing pH in the growth media. Formation of carbohydrate species in the culture broths was closely related to the biosynthesis and secretion of several carbohydrases by A. niger. The extracellular carbohydrases were separated and identified by chromatofocusing and polyacrylamide gel electrophoresis to be amyloglucosidase (EC 3.1.2.3), alpha-amylase (EC 3.2.1.1), and alpha-glucosidase (EC 3.2.1.20), respectively.

  3. Propriedades físicas de filmes biodegradáveis à base de amido de mandioca, álcool polivinílico e montmorilonita

    OpenAIRE

    2012-01-01

    The objective of this work was to manufacture biodegradable films based on cassava starch, polyvinyl alcohol (PVA) and sodium montmorillonite (Na-MMT), using glycerol as a plasticizer. These films were characterized according to their microstructure, optical, mechanical, and barrier properties. The combination of starch-PVA-MMT resulted in films with a more homogeneous surface than starch films. The introduction of PVA into the starch matrix led to the formation of films with lower water vapo...

  4. 木薯采后生理性变质与淀粉特性研究%Physiological Deterioration and Starch Characteristics of Harvest Cassava Tuberous Root

    Institute of Scientific and Technical Information of China (English)

    姚庆群; 张振文

    2012-01-01

    The rapid physiological deterioration (PD) of cassava tuberous root is main constraint factor that limits the development of cassava industry. In order to know the relationship between PD and starch characteristics on cassava, there are five varieties subjected ( SC205, SC5, SC6, SC8 and SC10) on four indices, including dry matter, starch content, amylopectin content and starch clarity. The result showed that the indices of starch characteristics were decreased by PD in all subjects, and the decline of SC205 was appeared earlier than others. The correlation analysis were indicated that Positive correlation and significant positive correlation between amylopectin content and starch content, amylopectin content respectively. Thus, we can see starch clarity was affected by the PD during storage, and starch quality of cassava tuberous root was also cut down greatly.%以华南系列的SC205、SC5、SC6、SC8和SCIO五个木薯品种为材料,于采收后不同时间分析其块根生理变质程度、干物质含量、淀粉含量、支链淀粉比例和淀粉透明度等指标,探讨木薯生理变质与块根淀粉特性的关系。研究结果表明:采后生理变质对块根淀粉特性有明显影响,所有品种淀粉特性指标在采后均呈下降趋势,其中下降最快的是SC205。对各指标的相关分析表明,支链淀粉分别与淀粉含量和淀粉透明度呈显著正相关和极显著正相关。可见,生理变质可导致淀粉透明度的下降,影响淀粉的商品品质。

  5. Properties of Edible Films Based on Oxidized Starch and Zein

    Directory of Open Access Journals (Sweden)

    Elizabeth Argüello-García

    2014-01-01

    Full Text Available The objective of this work was to investigate the effect of zein and film formulation on mechanical and structural properties of native (FNS, and oxidized with 2.5% (FOSA and 3.5% (FOSB banana starch. The oxidized starch showed differences from native starch due to the oxidation process, showing a decrease in lipids, proteins, and amylose. The increase of the sodium hypochlorite increased the content of carbonyl and carboxyl groups in the ranges 0.015–0.028% and 0.022–0.031%, respectively. The film obtained from FOSB displayed the highest tensile strength (5.05 MPa and satisfactory elongation value (27.1%. The zein addition caused a decrease in these mechanical properties, as well as a significant decrease in water vapour permeability (WVP. However, films from FOSA and FOSB showed higher permeability than that of the native starch. The addition of glycerol and the level of oxidation increased the films moisture. Micrographs showed that, during the oxidation process, impurities were largely eliminated from the starch granule, noting more homogeneous structures both in granules and films.

  6. Physical characteristics of extruded cassava starch Características físicas de amido de mandioca extrusado

    Directory of Open Access Journals (Sweden)

    Magali Leonel

    2009-08-01

    Full Text Available Considering the importance of cassava starch for Brazilian industries, the current work aimed at evaluating the effects of extrusion parameters on the physical characteristics, mainly viscosity properties of extruded cassava starch. A factorial central composite design (2³ with three independent variables and the response surface methodology were used to evaluate the results of expansion index, specific volume, water absorption index, water solubility index, color and paste properties, according to the variations in the moisture content, barrel temperature and screw speed. Results indicated that barrel temperature influenced the expansion index, specific volume, water absorption index, all the color parameters, the initial viscosity, peak and final viscosity. Feed moisture influenced the specific volume, color parameters, final viscosity and retrogradation. The screw speed had effects on water absorption index, color components as well as on the final viscosity and retrogradation of extruded starch. High moisture, low screw speed and intermediate temperature provided lower starch degradation, which is desirable for pre-cooked starch.Considerando a importância do amido de mandioca para as indústrias brasileiras, este trabalho teve por objetivo avaliar os efeitos de parâmetros de extrusão sobre as características físicas e propriedades de pasta do amido de mandioca extrusado. Foi utilizado o delineamento fatorial do tipo central composto rotacional com três variáveis independentes (2³ e a metodologia de superfície de resposta para avaliar os resultados de índice de expansão, volume específico, índice de absorção de água, índice de solubilidade em água, cor e propriedades de pasta, de acordo com as variações de umidade, temperatura de extrusão e rotação da rosca. A temperatura de extrusão influenciou o índice de expansão, volume específico, índice de absorção de água, todos os parâmetros de cor e a viscosidade

  7. 水解酶法回收木薯黄浆废水中的淀粉%Study on recovery of starch from cassava starch wastewater using aqueous enzymatic method

    Institute of Scientific and Technical Information of China (English)

    崔雯; 莫创荣; 李小明; 安鸿雪; 孙文博; 刘侃; 邓国龙

    2013-01-01

    以胰蛋白酶作为水解酶,采用水酶法从木薯黄浆废水中回收淀粉.通过调节酶加量、温度、时间、pH等因素,得到木薯淀粉的最佳回收条件:加酶量0.05 g/L,酶解时间3h,酶解温度35℃,酶解pH值为8.5.在最佳条件下得到沉淀物质量为10.85 g/L,沉淀物中淀粉含量为80.4 g/100 g,粗淀粉质量为8.72 g/L.%The aqueous enzymatic method was used to recovery of starch from cassava starch wastewater by using trypsin as hydrolase.The factors based on the enzyme dosage,temperature,time and pH.The best recovery conditions of cassava starch were as follows:the amount of enzyme 0.05 g/L,hydrolysis time 3 h,enzymolysis temperature 35 ℃,enzyme solution pH value 8.5.Under the optimum conditions obtained sediment quality of 10.85 g/L,starch content of sediment was 80.4 g/100 g,crude starch quality of 8.72 g/L.

  8. Synthesis, characterization and in vitro drug release of cisplatin loaded Cassava starch acetate–PEG/gelatin nanocomposites

    Directory of Open Access Journals (Sweden)

    V. Raj

    2016-10-01

    Full Text Available The aim of the present study is to examine the feasibility of Cassava starch acetate (CSA–polyethylene glycol (PEG–gelatin (G nanocomposites as controlled drug delivery systems. It is one of the novel drug vehicles which can be used for the controlled release of an anticancer drug. Simple nano precipitation method was used to prepare the carriers CSA–PEG–G nanocomposites and they were used for entrapping cisplatin (CDDP. Through FT-IR spectroscopy, the linking among various components of the system was proved and with the help of scanning electron microscope and transmission electron microscopy (TEM, the surface morphology was investigated. The particle sizes of the CSA–CDDP, CSA–CDDP–PEG and CSA–CDDP–PEG–G polymer composites were between 140 and 350 nm, as determined by a Zetasizer. Drug encapsulation efficiency, drug loading capacity and in vitro release of CDDP were evaluated respectively. The findings revealed that the cross linked CSA–PEG–G nanocomposites can be a potential polymeric carrier for controlled delivery of CDDP.

  9. Conservação pós-colheita de berinjela com revestimentos de fécula de mandioca ou filme de PVC Postharvest conservation of eggplant fruits by the application of cassava edible coating or PVC film

    Directory of Open Access Journals (Sweden)

    Pahlevi A de Souza

    2009-06-01

    Full Text Available Com o objetivo de avaliar a conservação pós-colheita de berinjelas revestidas com filmes de PVC ou películas de fécula de mandiocaa 3%, foram colhidos frutos de berinjela, cultivar Embú, aos 147 dias após a semeadura em campo da UFERSA em Mossoró-RN. Os frutos foram transportados ao Laboratório de Pós-Colheita e armazenados por 15 dias em condições ambientais (26 a 29ºC; UR de 50-75%. O delineamento experimental foi inteiramente casualizado em esquema fatorial 3 x 6, com três repetições e três frutos por parcela. Os tratamentos constaram da combinação de 3 tipos de revestimento (controle, fécula de mandioca a 3% ou filme plástico e 6 tempos de armazenamento (0; 3; 6; 9; 12 ou 15 dias. Avaliou-se a aparência externa (escala 1-5, perda de massa (%, firmeza da polpa (N e teores de sólidos solúveis (º Brix, acidez total (% de ácido cítrico e ácido ascórbico (mg/100 g polpa. O uso do filme plástico foi eficiente em manter a aparência externa e reduzir a perda de massa. O uso de fécula de mandioca não foi eficiente em prolongar a vida útil póscolheita da berinjela quando comparado com o uso de filme plástico. Baseado na aparência externa, o período de conservação da berinjela foi de 15, 12 e 9 dias para os tratamento com filme plástico, fécula de mandioca e controle, respectivamente.The postharvest conservation of eggplant fruits covered with cassava starch at 3% or covered with PVC film was compared. Fruits of the cultivar Embú were taken 147 days after sowing date in the field, in Mossoró, Rio Grande do Norte State, Brazil. Afterwards, the fruits were taken to the Postharvest Laboratory and stored during 15 days in environmental conditions (26-29oC and 50-75% RH. A 3 x 6 factorial scheme with three replications of three fruits per plot in a completely randomized design was used. The treatments consisted of the combination of three coating types (control, cassava starch and polyethylene film with six

  10. Morfología Superficial de Almidones Termoplásticos Agrio de Yuca y Nativo de Papa por Microscopía Óptica y de Fuerza Atómica Surface Morphology of Sour Cassava and Native Potato Thermoplastic Starches by Optical and Atomic Force Microscopy

    Directory of Open Access Journals (Sweden)

    Harold A Acosta

    2006-01-01

    Full Text Available Se ha evaluado la morfología superficial de almidones termoplásticos (TPS obtenidos de almidones agrio de yuca y nativo de papa, extruidos con tornillo simple, usando microscopía óptica de alta resolución (OM y de fuerza atómica (AFM. Muestras de almidones agrio de yuca y nativo de papa más glicerina, se procesaron a 120 ºC y 50 rpm, dando extruidos que se cortaron en láminas delgadas, que se observaron por OM y AFM (modo contacto intermitente. El almidón nativo de papa mostró grandes gránulos ovoides y el almidón agrio de yuca reveló el ataque enzimático debido a la fermentación natural. Los TPS mostraron superficies lisas y rugosas dependiendo de la forma y el tamaño del gránulo, de la fermentación natural y del contenido de plastificante. Los TPS nativo de papa exhibieron pocas superficies lisas por OM y alta rugosidad por AFM; lo contrario se presentó con el TPS agrio de yuca, debido a su fermentación natural previa. Estos resultados contribuyen a predecir y entender las propiedades microestructurales, mecánicas y texturales de los almidones termoplásticos.An evaluation was made of the surface morphology of thermoplastic starches (TPS from sour cassava and native potato, extruded with a single-screw extruder, using high-resolution optical microscopy (OM and atomic force microscopy (AFM. Samples of sour cassava starch and native potato starch and glycerine, were processed at 120(0C and 50 rpm, producing extrudates which were cut into thin films for observation by OM and AFM (intermittent contact mode. Native potato starch showed large ovoid granules, while sour cassava starch revealed enzyme attack due to natural fermentation. The TPS had smooth and rough surfaces, depending upon granule size and shape, starch fermentation, and plasticizer content. Native potato TPS presented few smooth surfaces by OM and high roughness by AFM. The opposite was observed with sour cassava TPS, which had experienced some previous natural

  11. Caracterização de amidos de mandioca nativos e modificados e utilização em produtos panificados Characterization of native and modified cassava starches and their use in baked products

    Directory of Open Access Journals (Sweden)

    Krischina Singer Aplevicz

    2007-09-01

    Full Text Available O amido de mandioca é utilizado como ingrediente principal na fabricação de biscoitos e pão de queijo. O polvilho azedo é um produto artesanal, sem padrão de qualidade estabelecido, com problemas de higiene em seu processamento e de oferta. O trabalho teve como objetivo caracterizar amidos de mandioca nativos e modificados e testá-los na elaboração de pão de queijo e biscoito de polvilho. As principais características que diferem o polvilho azedo do amido de mandioca nativo, também denominado polvilho doce são: acidez, grau de expansão, viscosidade, claridade de pasta, sinérese e poder redutor. Foram aplicados nos produtos panificados quatro tipos de amidos, sendo polvilho doce, azedo, amido modificado com peróxido de hidrogênio e amido modificado comercial Expandex® 160003. Obtidos os produtos panificados, foi determinada a composição físico-química e observado que os tipos de amidos influenciaram nas características internas, externas e no sabor. Os produtos panificados foram submetidos à análise sensorial de aceitabilidade, utilizando-se a escala hedônica de nove pontos, com provadores não-treinados. As amostras de pão de queijo contendo amido modificado oxidado com peróxido de hidrogênio foram as que apresentaram o melhor resultado entre as formulações. Para as amostras de biscoito de polvilho, as elaboradas com polvilho azedo e com Expandex® 160003 foram superiores e não diferiram estatisticamente.Cassava starch is used as the main ingredient in the production of biscuits and Brazilian cheese bread. The processing and sale of sour cassava starch - an artisanal product with no established standard of quality - is marked by hygiene problems and its commercial availability is uncertain. The purpose of this study was to characterize native and modified cassava starches and test them in cheese bread and cassava starch biscuit recipes. The main characteristics that differentiate sour starch from native cassava

  12. Influence of hydroxypropylmethylcellulose addition and homogenization conditions on properties and ageing of corn starch based films.

    Science.gov (United States)

    Jiménez, Alberto; Fabra, María José; Talens, Pau; Chiralt, Amparo

    2012-06-20

    Edible films based on corn starch, hydroxypropyl methylcellulose (HPMC) and their mixtures were prepared by using two different procedures to homogenize the film forming dispersions (rotor-stator and rotor-stator plus microfluidizer). The influence of both HPMC-starch ratio and the homogenization method on the structural, optical, tensile and barrier properties of the films was analysed. The ageing of the films was also studied by characterizing them after 5 weeks' storage. Starch re-crystallization in newly prepared and stored films was analysed by means of X-ray diffraction. HPMC-corn starch films showed phase separation of polymers, which was enhanced when microfluidization was applied to the film forming dispersion. Nevertheless, HPMC addition inhibited starch re-crystallization during storage, giving rise to more flexible films at the end of the period. Water barrier properties of starch films were hardly affected by the addition of HPMC, although oxygen permeability increased due to its poorer oxygen barrier properties.

  13. 湿热处理对木薯淀粉结构和性质的影响%Effect of heat-moisture treatment on structure and properties of cassava starch

    Institute of Scientific and Technical Information of China (English)

    汪树生; 杨秋实; 苏玉春; 陈光

    2013-01-01

    对木薯淀粉进行湿热处理,研究了不同初始含水量对木薯淀粉结构和性质的影响.实验结果表明:经湿热处理后的木薯淀粉颗粒表面出现凹坑,随着初始含水量增加,淀粉颗粒表面凹坑的数量增加,同时黏结现象变得严重;湿热处理木薯淀粉的糊化温度随着初始含水量的增加而升高;经湿热处理后,木薯淀粉对酸和酶的敏感性增加,更容易被酸和酶水解.%Cassava starch was heat-moisture treated and the effects of initial moisture on the structure and properties of heat-moisture treated cassava starch were studied. The results indicated that there were dents on the surface of starch granule, the number of dents increased alone with the ascent of initial moisture of heat-moisture treated cassava starch, while the bonding of starch granule became serious. The gelatinization temperature of heat-moisture treated cassava starch increased with the higher of initial moisture. The cassava starch became sensitive to acid or enzyme hydrolysis after heat-moisture treatment, easier to be hydrolyzed by acid or enzyme.

  14. Effect of cassava starch coating on quality and shelf life of fresh-cut pineapple (Ananas comosus L. Merril cv "Pérola").

    Science.gov (United States)

    Bierhals, Vânia S; Chiumarelli, Marcela; Hubinger, Miriam D

    2011-01-01

    This research studied the influence of treatment with ascorbic acid, citric acid, and calcium lactate dipping and cassava starch edible coatings on quality parameters and shelf life of fresh-cut pineapple in slices during 12 d at 5 °C. After previous tests, the treatments selected for this study were samples dipped into antibrowning solution with 0.5% of ascorbic acid and 1% of citric acid, with and without 2% of calcium lactate and coated with 2% of cassava starch suspensions. Changes in weight loss, juice leakage, mechanical properties (stress at failure), color parameters (L* and H*), ascorbic acid content, sensory acceptance, and microbial growth of fruits were evaluated. Samples only treated with antibrowning agents were used as control. Edible coatings with and without calcium lactate were efficient in reducing weight loss, juice leakage, and maintaining firmness during storage. However, these samples showed more browning and the ascorbic acid content was reduced. All treatments presented good sensory acceptance (scores above 6). The determining factor of shelf life of pineapple slices was the microbial spoilage. A shelf life of 8 d was obtained for pineapple slices only treated with antibrowning agents. On the other hand, coated samples showed a reduced shelf life of 7 d and higher yeast and mold growth. Thus, although cassava starch coatings were efficient in reducing respiration rate, weight loss, and juice leakage and maintained mechanical properties, these treatments were not able to increase the shelf life of minimally processed pineapple. Practical Application: Pineapple fruit is highly appreciated for its aroma, flavor, and juiciness, but its immediate consumption is difficult. Therefore, pineapple is a potential fruit for minimal processing. However, shelf life of fresh-cut pineapple is very limited by changes in color, texture, appearance, off-flavors, and microbial growth. The use of edible coatings as gas and water vapor barrier and antibrowning

  15. Characterization of Starch Edible Films with Different Essential Oils Addition

    Directory of Open Access Journals (Sweden)

    Šuput Danijela

    2016-12-01

    Full Text Available This study investigated properties of starch-based edible films with oregano and black cumin essential oil addition. Essential oils addition positively affected film swelling (decreased due to essential oil addition, mechanical properties (tensile strength decreased while elongation at break increased, and water vapor barrier properties (decreased along with essential oils addition. Control film did not have any biological activity, which proves the need for essential oils addition in order to obtain active packaging. Oregano oil was more effective in terms of biological activity. Endothermal peak, above 200°C, represents total thermal degradation of edible films. Diffraction pattern of control film showed significant destruction of A-type crystal structure. Addition of essential oils resulted in peak shape change: diffraction peaks became narrower. Principal Component Analysis has been used to assess the effect of essential oils addition on final starch-based edible films characteristics with the aim to reveal directions for the film characteristics improvement, since the next phase will be optimal film application for food packaging.

  16. Influence of thickness on properties of plasticized oat starch films

    Directory of Open Access Journals (Sweden)

    Melicia Cintia Galdeano

    2013-08-01

    Full Text Available The aim of this study was to investigate the effect of thickness (between 80 and 120 µm on apparent opacity, water vapor permeability and mechanical properties (tensile and puncture of oat starch films plasticized with glycerol, sorbitol, glycerol:sorbitol mixture, urea and sucrose. Films were stored under 11, 57, 76 and 90% relative humidity (RH to study the mechanical properties. It was observed that the higher the thickness, the higher was the opacity values. Films without the plasticizer were more opaque in comparison with the plasticized ones. Glycerol:sorbitol films presented increased elongation with increasing thickness at all RH. Puncture force showed a strong dependence on the film thickness, except for the films plasticized with sucrose. In general, thickness did not affect the water permeability.

  17. Adhesion of an Amylolytic Arthrobacter sp. to Starch-Containing Plastic Films

    OpenAIRE

    1990-01-01

    Cells of the amylolytic bacterium KB-1 (thought to be an Arthrobacter sp.) adhered (∼70%) to the surface of plastic films composed of starch-poly (methylacrylate) graft copolymer (starch-PMA), but did not adhere (

  18. Solid Substrate Fermentation of Cassava Peel for Poultry Feed Ingredient

    OpenAIRE

    Stephanie; Purwadaria T

    2013-01-01

    Cassava peel which is not used during cassava starch extraction is one of potential resources for animal feed. However, cassava peel has low level protein content, high level crude fiber, and high level of toxic cyanogenic compound. These problems limit the utilization of cassava peel as feed. Solid substrate fermentation using mold may be a solution process to increase its nutritional value and decrease toxic level of cassava peel. In this paper, matters that related with cassava peel fermen...

  19. Effects of crosslinking temperature and time on microstructure and stability of cassava starch microspheres.

    Science.gov (United States)

    Puncha-Arnon, Santhanee; Jiranuntakul, Wittawat; Uttapap, Dudsadee

    2015-12-10

    Starch microspheres (SMs) were prepared by a water-in-water emulsion-crosslinking technique at 4 °C and 30 °C for 1, 6, 12 and 24h; the SMs obtained were analyzed for crosslinking density, morphology, crystalline structure, and stability against temperature, pH, and α-amylase hydrolysis. The crosslinking degree at 30 °C was considerably higher than that at 4 °C. SMs prepared at 4 °C for less than 12h incubation had larger size and more porous structure as compared with those prepared at 30 °C, but the morphology became comparable (spherical shape with smooth surface and dense structure) after 24h incubation. All SMs samples displayed amorphous structure. Stability tests revealed that the SMs were very stable under acidic and mild basic pH; however, stability against α-amylase hydrolysis varied depending on incubation temperature and time.

  20. A physicochemical study of sugar palm (Arenga Pinnata) starch films plasticized by glycerol and sorbitol

    Science.gov (United States)

    Poeloengasih, Crescentiana D.; Pranoto, Yudi; Hayati, Septi Nur; Hernawan, Rosyida, Vita T.; Prasetyo, Dwi J.; Jatmiko, Tri H.; Apriyana, Wuri; Suwanto, Andri

    2016-02-01

    The present work explores the physicochemical characteristics of sugar palm starch film for a potential hard capsule purpose. Sugar palm (Arenga pinnata) starch films were plasticized with glycerol or sorbitol in various concentrations (30% up to 50% w/w starch). Their effects on physicochemical properties of the films were investigated. The results showed that sugar palm starch was successfully developed as the main material of film using casting method. Incorporation of both glycerol or sorbitol affected the properties of films in different ways. It was found that thickness and solubility increased as plasticizer concentration increased, whereas retraction ratio, swelling degree and swelling thickness decreased with the increased plasticizer concentration.

  1. Morphological and mechanical properties of thermoplastic starch (TPS) and its blend with poly(lactic acid)(PLA) using cassava bagasse and starch; Caracterizacao morfologica e mecanica de amidos termoplasticos (TPS) e suas blendas com poliacido latico (PLA) utilizando bagasso e amido de mandioca

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, Eliangela de M.; Correa, Ana C.; Campos, Adriana de; Marconcini, Jose M.; Mattoso, Luiz H.C. [Embrapa Instrumentacao Agropecuaria-CNPdia, Laboratorio Nacional de Nanotecnologia para o Agronegocio - LNNA, Sao Carlos, SP (Brazil); Curvelo, Antonio A.S. [Universidade de Sao Paulo-USP, Instituto de Quimica da USP de Sao Carlos, SP (Brazil)

    2011-07-01

    This study aims the use of an agro waste coming from the industrialization of cassava starch, known as cassava bagasse (BG). This material contains residual starch and cellulose fibers which can be used to obtain thermoplastic starch (TPS) and /or blends reinforced with fibers. In this context, it was prepared a thermoplastic starch with BG (TPSBG) and evaluated the incorporation of 20wt% of it into the biodegradable polymer poly (lactic acid) (PLA), resulting in a blend PLA/TPSBG20. The materials were investigated through morphology (scanning electron microscopy with field emission gun (FEG), x-ray diffraction (XRD), and mechanical behavior (tensile test). Their properties were compared to the blend PLA/TPSI20 in which TPSI is obtained from commercial cassava starch. The results showed that the use of bagasse generates homogenous materials with higher mechanical strength if compared to TPS obtained from commercial cassava starch. The fiber in this residue acted as reinforcement for TPS and PLA/TPS systems. (author)

  2. Synthesis and characterisation of simultaneous interpenetrating polymer networks (SIN formed by polystyrene and polyurethane obtained from castor oil and cassava starch polyol-suspensions

    Directory of Open Access Journals (Sweden)

    Juan Manuel Cabrera Anaya

    2011-01-01

    Full Text Available Castor oil was modified by transesterification with pentaerythritol and cassava starch was subsequently incorporated into this oil (oil modified by incorporating starch is called a polyol-suspension. Polyurethane/polystyrene SINs (simulta- neously produced IPNs were synthesised from them and styrene. Reactants used in the synthesis were MDI (methylene diphenyl diisocyanate as diisocyanate, DVB (divinylbenzene as crosslinking agent for polystyrene, dibutylamine as redox primer and benzoyl peroxide as styrene polymerisation primer. The variables considered in SIN synthesis were percentage weight ratio used in the modification (1.32%; 2.64% and 5.28% to increase polyol hydroxyl functionality, starch species incorporated into polyol (Brazilian, Venezuelan and commercial to vary the amount of amylopectin within the polyol-suspension, diisocyanate/hydroxyl NCO/OH (0.85 and 1 functional groups’ molar ratio and polyurethane/ polystyrene PU/PS weight ratio (70/30 and 80/20. A wide range of materials was obtained and characterised by tensile strength, hardness, chemical attack and Soxhlet extraction. The physical-mechanical properties of the materials produced with polyols (transesterified castor oil were improved when starch was incorporated into the polyol. Several tests indicated that 24 hours as curing time were not enough, because the SINs showed lower physical-mechanical properties than the homologous polyurethane elastomers did; thus, the curing time had to be increased to 48 hours.

  3. Properties of cassava cross-linked carboxymethylated starch(Ⅰ)%木薯交联羧甲基淀粉的性质研究(Ⅰ)

    Institute of Scientific and Technical Information of China (English)

    谭义秋; 黄祖强; 农克良

    2013-01-01

    采用搅拌球磨机对木薯淀粉进行机械活化,以活化60 min的木薯淀粉为原料,环氧氯丙烷为交联剂,一氯乙酸钠为醚化剂制备交联羧甲基淀粉,对交联羧甲基淀粉的溶解度,糊的透明度、冻融稳定性、抗老化、抗酸、抗剪切等性质进行研究.结果表明,相对于交联淀粉,交联羧甲基淀粉的溶解度增大、糊的透明度增大;相对于羧甲基淀粉,交联羧甲基淀粉的溶解度减小,糊的透明度降低;相对于交联淀粉和羧甲基淀粉,交联羧甲基淀粉糊的冻融稳定性、抗老化、抗酸和抗剪切能力增强.%The cross-linked carboxymethylated starch was prepared by cassava starch, mechanically activated for 60 min by a stirring-type ball mill, as a starting material, epichlorohydrin as cross-linked agent, and sodium chloroacetate as etherifying a-gent. The properties of the cross-linked carboxymethylated starch, such as solubility, transparency, freeze-thaw stability, anti-retrogradation ability, anti-acid ability and anti-shearing ability, were studied. The results showed that solubility and transparency of the cross-linked carboxymethylated starch increased compared to the cross-linked starch; solubility and transparency of the cross-linked carboxymethylated starch decreased compared to carboxymethylated starch; and the freeze-thaw stability, anti-retrogradation ability, anti-acid ability, and anti-shearing ability of the cross-linked carboxymethylated starch were enhanced compared to the cross-linked starch and carboxymethylated starch.

  4. Endophytic fungi from the Amazonian plant Paullinia cupana and from Olea europaea isolated using cassava as an alternative starch media source.

    Science.gov (United States)

    Sia, Eliandra de Freitas; Marcon, Joelma; Luvizotto, Danice Mazzer; Quecine, Maria Carolina; Tsui, Sarina; Pereira, José Odair; Pizzirani-Kleiner, Aline Aparecida; Azevedo, João Lúcio

    2013-01-01

    Endophytic fungi live inside plants, apparently do not cause any harm to their hosts and may play important roles in defense and growth promotion. Fungal growth is a routine practice at microbiological laboratories, and the Potato Dextrose Agar (PDA) is the most frequently used medium because it is a rich source of starch. However, the production of potatoes in some regions of the world can be costly. Aiming the development of a new medium source to tropical countries, in the present study, we used leaves from the guarana (a tropical plant from the Amazon region) and the olive (which grows in subtropical and temperate regions) to isolate endophytic fungi using PDA and Manihot Dextrose Agar (MDA). Cassava (Manihot esculenta) was evaluated as a substitute starch source. For guarana, the endophytic incidence (EI) was 90% and 98% on PDA and MDA media, respectively, and 65% and 70% for olive, respectively. The fungal isolates were sequenced using the ITS- rDNA region. The fungal identification demonstrated that the isolates varied according to the host plant and media source. In the guarana plant, 13 fungal genera were found using MDA and six were found using PDA. In the olive plant, six genera were obtained using PDA and 4 were obtained using MDA. The multivariate analysis results demonstrated the highest fungal diversity from guarana when using MDA medium. Interestingly, some genera were isolated from one specific host or in one specific media, suggesting the importance of these two factors in fungal isolation specificity. Thus, this study indicated that cassava is a feasible starch source that could serve as a potential alternative medium to potato medium.

  5. Effect of oil lamination between plasticized starch layers on film properties.

    Science.gov (United States)

    Basiak, Ewelina; Debeaufort, Frédéric; Lenart, Andrzej

    2016-03-15

    To reduce the hygroscopic character of biodegradable starch-based films, rapeseed oil was incorporated by lamination (starch-oil-starch 3-layers technique). The lipid lamination followed by starch solution casting step induced an emulsion type structure of dried films. Composite films are more opalescent and glossier than fatty free starch films. For all the films, structure is heterogeneous in the cross-section only. Adding fat induced a twice decrease of the tensile strength. Thermal gravimetry analysis did not show differences between films with and without oil. Lipid reduced the moisture absorption particularly at higher RH as well as the surface swelling index, when water droplet contact occurred. Addition of lipids always decreases the contact angle for all liquid tested, except for water. Surface affinity of films for liquids less polar that water increased with rapeseed oil addition. The addition of rapeseed oil significantly reduces water vapour and oxygen permeability.

  6. Biodegradation of starch films: the roles of molecular and crystalline structure.

    Science.gov (United States)

    Li, Ming; Witt, Torsten; Xie, Fengwei; Warren, Frederick J; Halley, Peter J; Gilbert, Robert G

    2015-05-20

    The influences of molecular, crystalline and granular structures on the biodegradability of compression-molded starch films were investigated. Fungal α-amylase was used as model degradation agent. The substrates comprised varied starch structures obtained by different degrees of acid hydrolysis, different granular sizes using size fractionation, and different degrees of crystallinity by aging for different times (up to 14 days). Two stages are identified for unretrograded films by fitting degradation data using first-order kinetics. Starch films containing larger molecules were degraded faster, but the rate coefficient was independent of the granule size. Retrograded films were degraded much slower than unretrograded ones, with a similar rate coefficient to that in the second stage of unretrograded films. Although initially the smaller molecules or the easily accessible starch chains on the amorphous film surface were degraded faster, the more ordered structure (resistant starch) formed from retrogradation, either before or during enzymatic degradation, strongly inhibits film biodegradation.

  7. Study on the properties of cassava hydroxypropyl and octenyl succinic anhydride compound modified starch%木薯羟丙基化辛烯基琥珀酸酯化复合改性淀粉的性质研究

    Institute of Scientific and Technical Information of China (English)

    雷欣欣; 张本山; 周雪

    2012-01-01

    以木薯淀粉为原料制备木薯羟丙基化辛烯基琥珀酸酯化复合改性淀粉,采用傅里叶变换红外谱仪、扫描电镜、X射线衍射仪和Brabender黏度仪等对木薯羟丙基化辛烯基琥珀酸酯化复合改性淀粉的物化性质进行了测定和分析.并与木薯原淀粉和木薯辛烯基琥珀酸淀粉酯进行对比。结果表明,木薯淀粉经复合改性后,在1550-1610cm-1出现新的吸收峰.与原木薯淀粉和木薯SSOS相比,在940、880、730、570cm-1处呈现较弱的吸收峰;复合改性后颗粒表面受损严重.颗粒的形状也发生明显改变,但晶体类型没有发生改变;乳化性能和透明度得到提高;起糊温度、峰值温度降低.糊粘度增大;与单一的辛烯基琥珀酸酯化改性淀粉相比,热糊稳定性升高,凝沉性增强。%The cassava starch was used to prepare cassava hydroxypropyl and octenyl succinic anhydride compound modified starch. The physical properties of cassava hydroxypropyl and octenyl succinic anhydride compound modified starch were investigated by Fourier transform infrared spectrometer(FT-IR),Scanning electron microscop,X-ray diffraction(XRD),Brabender viscometer and so on with the comparison of the native cassava starch and octenyl succinic anhydride(OSA)-modified cassava starch. The results indicated that the FT-IR spectrum of compound modified cassava starch showed new absorption peaks at 1550-1610cm-1. and weaken absorption peak at the 940,880,730 and 570cm-1,compared with the native cassava starch and OSA- modified cassava starch. The starch granule exhibited rougher surface,more irregular shape significantly but the crystalline was not changed. The product showed good emulsifiability and transparency. That gelatinization temperature and the peak temperature all decreased,and paste viscosity was higher as well.The setback capacity was weaker,and hot paste stability increased,compared with single octenyl succinic anhydride

  8. Effect of organoclay on morphology and properties of linear low density polyethylene and Vietnamese cassava starch biobased blend.

    Science.gov (United States)

    Nguyen, D M; Vu, T T; Grillet, Anne-Cécile; Ha Thuc, H; Ha Thuc, C N

    2016-01-20

    Linear low density polyethylene (LLDPE)/thermal plastic starch (TPS) blend was studied to prepare the biobased nanocomposite material using organoclay nanofil15 (N15) modified by alkilammonium as the reinforced phase. The LLDPE/TPS blend and its nanocomposites were elaborated by melt mixing method at 160 °C for 7 min. And the compounded sample was filmed by blowing method at three different zones of temperature profile which are 160-170-165 °C. The good dispersion of clay in the polymer blend matrix is showed by X-ray diffraction (XRD) and transmission electronic microscopy (TEM), and a semi-exfoliated structure was obtained. The thermal and mechanical properties of materials are enhanced when N15 is added to the mixture. The effect of N15 on morphology and particles size of TPS phase is also investigated. The biodegradation test shows that more than 60% in weight of LLDPE/TPS film is degraded into CO2, H2O, methane and biomass after 5 months in compost soil.

  9. Preparation and properties of resistant starch from fresh cassava%鲜木薯抗性淀粉的制备与性质

    Institute of Scientific and Technical Information of China (English)

    薛慧; 闫庆祥; 蒋盛军; 张国治; 台建祥; 吕飞杰

    2013-01-01

    Many studies have shown that resistant starch has health benefits such as preventing colon cancer, reducing the risk of ulcerative colitis, increasing absorption of minerals, inhibiting fat accumulation and hypoglycemic effects. In this study, the cassava starch was used as raw material. The resistant starch was prepared by autoclaving assisted enzyme treatment. To improve the content of resistant starch, the parameters of enzyme treatment that include adding amounts ofα-amylase, reaction time ofα-amylase, adding amounts of pullulanase and reaction time of pullulanase were optimized with a response surface methodology. The F-value of 57.58 implies the model is significant. The Lack of Fit F-value of 1.66 implies the Lack of Fit is not significant relative to the pure error. The Pred R-Squared of 0.9156 is in reasonable agreement with the Adj R-Squared of 0.9659 and the R-Squared is 0.9829. This model can be used to navigate the design space. The optimized conditions were that when 10%of the starch slurry concentration was autoclaved at 120℃ for 80min, added 1Uα-amylase per gram of starch to react 15.75 min at 95℃, debranched with 0.83U pullulanase per gram of starch at 55℃ for 5.86h, then treated with ultrasonic for 2min, and finally retrograded at 4℃ for 24h to improve resistant starch formation, the content of resistant starch increased to 15.48%. Compared with raw starch, the granule appearance of resistant starch changed under scanning electron microscopy. X-ray diffraction showed that the cassava starch had an A type pattern with sharp peaks at 15°, 17°, 18°and 23°. However, the resistant starch had a B type pattern with sharp peaks at 17°and 22°. The crystallinity of resistant starch improved with increasing resistant starch content. The in vitro digestion results indicated that total carbohydrate digestion products were decreased with increasing resistant starch content and that digestion rates were decreased with increasing incubation time

  10. Modification on liquid retention property of cassava starch by radiation grafting with acrylonitrile. I. Effect of γ-irradiation on grafting parameters

    Science.gov (United States)

    Kiatkamjornwong, S.; Chvajarernpun, J.; Nakason, C.

    1993-07-01

    Radiation modification on liquid retention properties of native cassava starch, gelatinized at 85°C, by graft copolymerization with acrylonitrile was carried out by mutual irradiation to gamma-rays. A thin aluminum foil was used to cover the inner wall of the reaction vessel, so that the homopolymer concentration was reduced to be less than 1.0% with a distilled water retention value of 665 g/g of the dry weight of the saponified grafted product. Confirmation of graft copolymerization and saponification reactions was made by the infrared spectrophotometric technique. The combined effect of radiation parameters in terms of an irradiation time and a dose rate to the total dose on the extent of the grafting reaction expressed in terms of grafting parameters which directly influenced liquid retention values was evaluated in conjunction with statistical analysis.

  11. Comparative study on properties of edible films based on pinhao (Araucaria angustifolia) starch and flour

    Science.gov (United States)

    The aim of this study was to develop and compare the properties of edible films based on pinhao starch and pinhao flour. Seven formulations were developed by casting methodology: 5% pinhao starch with 0, 1, 1.5, and 2% glycerol, and 5% pinhao flour with 1, 1.5, and 2% glycerol. The films were evalua...

  12. Edible Film Making of Starch Canna Tuber (Canna Edulis Kerr) and Aplication to Packaging Galamai

    OpenAIRE

    Hafnimardiyanti Hafnimardiyanti; M.Ikhlas Armin; Martalius Martalius

    2014-01-01

    Canna (Canna edulis Kerr) was a tuber that had a high carbohydrate content so canna had excellent prospects to develop into edible film. The purpose of this study was to make edible film of canna starch, knowing storability galamai was packed with edible film and determine the level of preference panelists through organoleptic tests. In this research, manufacture of edible films with various concentrations of canna starch 2%, 3%, 4% and the use of plasticizer (glycerol) 1%, 2% and 3% with 100...

  13. Impact of acid and oxidative modifications, single or dual, of sorghum starch on biodegradable films.

    Science.gov (United States)

    Biduski, Bárbara; Silva, Francine Tavares da; Silva, Wyller Max da; Halal, Shanise Lisie de Mello El; Pinto, Vania Zanella; Dias, Alvaro Renato Guerra; Zavareze, Elessandra da Rosa

    2017-01-01

    The objective of this study was to evaluate the effects of acid and oxidation modifications on sorghum starch, as well as the effect of dual modification of starch on the physical, morphological, mechanical, and barrier properties of biodegradable films. The acid modification was performed with 3% lactic acid and the oxidation was performed with 1.5% active chlorine. For dual modification, the acid modification was performed first, followed by oxidation under the same conditions as above. Both films of the oxidized starches, single and dual, had increased stiffness, providing a higher tensile strength and lower elongation when compared to films based on native and single acid modified starches. However, the dual modification increased the water vapor permeability of the films without changing their solubility. The increase in sorghum starch concentration in the filmogenic solution increased the thickness, water vapor permeability, and elongation of the films.

  14. Effect of plasticizer on moisture sorption isotherm of sugar palm (Arenga Pinnata) starch film

    Science.gov (United States)

    Jatmiko, Tri Hadi; Poeloengasih, Crescentiana D.; Prasetyo, Dwi Joko; Rosyida, Vita Taufika

    2016-02-01

    The effect of plasticizer type (glycerol, sorbitol) and plasticizer concentrations (30, 35, 40, 45% w/w polymer) on the moisture sorption isotherm characteristics of sugar palm (Arenga pinnata) starch films were investigated. Moisture affinity of sugar palm starch films was influenced by the plasticizer type and plasticizer concentration. The affinity of the glycerol plasticized film is stronger than that of sorbitol plasticized film. Sugar palm starch film with a higher concentration of glycerol absorbs more moisture with higher initial absorption rate than that of with sorbitol. Films with higher plasticizer concentration of glycerol and sorbitol show higher equilibrium moisture contents at the given relative humidity. The moisture sorption isotherm characteristic of sugar palm starch films can be described very well with the semi empirical 4 parameter Peleg's model.

  15. Effect of starch type on the physico-chemical properties of edible films.

    Science.gov (United States)

    Basiak, Ewelina; Lenart, Andrzej; Debeaufort, Frédéric

    2017-05-01

    Food preservation is mostly related to packaging in oil-based plastics, inducing environmental problems, but this drawback could be limited by using edible/biodegradable films and coatings. Physical and chemical properties were assessed and reflect the role of the starch type (wheat, corn or potato) and thus that of the amylose/amylopectin ratio, which influences thickness, colour, moisture, wettability, thermal, surface and mechanical properties. Higher amylose content in films induces higher moisture sensitivity, and thus affects the mechanical and barrier properties. Films made from potato starch constitute a greater barrier for oxygen and water vapour though they have weaker mechanical properties than wheat and corn starch films. Starch species with higher amylose content have lower wettability properties, and better mechanical resistance, which strongly depends on the water content due to the hydrophilic nature of starch films, so they could be used for products with higher water activity, such as cheese, fruits and vegetables. It especially concerns wheat starch systems, and the contact angle indicates less hydrophilic surfaces (above 90°) than those of corn and potato starch films (below 90°). The starch origin influences optical properties and thickness: with more amylose, films are opalescent and thicker; with less, they are transparent and thinner.

  16. Gelatin/potato starch edible biocomposite films: Correlation between morphology and physical properties.

    Science.gov (United States)

    Podshivalov, Aleksandr; Zakharova, Mariia; Glazacheva, Ekaterina; Uspenskaya, Mayya

    2017-02-10

    The paper presents the results of studies of the microstructure morphology and the operational properties of the gelatin/potato starch/glycerol edible biocomposite films varying in the starch content from 0 to 50wt% prepared by casting film-forming solution and dying at 36°C for 15h. The biocomposite films were shown phase separated heterogeneous morphology with the gelatin matrix as a continuous phase and microgranules of starch as a minor phase. It is found that when the starch content ≤ 30wt% the phase separation mechanism is nucleation and grow, whereas the starch content > 30wt% then the spinodal decomposition is the dominant mechanism. The work focuses on findings the influence of the phase separation mechanisms on the size of starch granules during the drying process, as well as the impact of these mechanisms on optical, frictional, mechanical, thermal and water-barrier properties.

  17. Multi-objective optimization of bioethanol production during cold enzyme starch hydrolysis in very high gravity cassava mash.

    Science.gov (United States)

    Yingling, Bao; Li, Chen; Honglin, Wang; Xiwen, Yu; Zongcheng, Yan

    2011-09-01

    Cold enzymatic hydrolysis conditions for bioethanol production were optimized using multi-objective optimization. Response surface methodology was used to optimize the effects of α-amylase, glucoamylase, liquefaction temperature and liquefaction time on S. cerevisiae biomass, ethanol concentration and starch utilization ratio. The optimum hydrolysis conditions were: 224 IU/g(starch) α-amylase, 694 IU/g(starch) glucoamylase, 77°C and 104 min for biomass; 264 IU/g(starch) α-amylase, 392 IU/g(starch) glucoamylase, 60°C and 85 min for ethanol concentration; 214 IU/g(starch) α-amylase, 398 IU/g(starch) glucoamylase, 79°C and 117 min for starch utilization ratio. The hydrolysis conditions were subsequently evaluated by multi-objectives optimization utilizing the weighted coefficient methods. The Pareto solutions for biomass (3.655-4.380×10(8)cells/ml), ethanol concentration (15.96-18.25 wt.%) and starch utilization ratio (92.50-94.64%) were obtained. The optimized conditions were shown to be feasible and reliable through verification tests. This kind of multi-objective optimization is of potential importance in industrial bioethanol production.

  18. Effect of cellulose reinforcement on the properties of organic acid modified starch microparticles/plasticized starch bio-composite films.

    Science.gov (United States)

    Teacă, Carmen-Alice; Bodîrlău, Ruxanda; Spiridon, Iuliana

    2013-03-01

    The present paper describes the preparation and characterization of polysaccharides-based bio-composite films obtained by the incorporation of 10, 20 and 30 wt% birch cellulose (BC) within a glycerol plasticized matrix constituted by the corn starch (S) and chemical modified starch microparticles (MS). The obtained materials (coded as MS/S, respectively MS/S/BC) were further characterized. FTIR spectroscopy and X-ray diffraction were used to evidence structural and crystallinity changes in starch based films. Morphological, thermal, mechanical, and water resistance properties were also investigated. Addition of cellulose alongside modified starch microparticles determined a slightly improvement of the starch-based films water resistance. Some reduction of water uptake for any given time was observed mainly for samples containing 30% BC. Some compatibility occurred between MS and BC fillers, as evidenced by mechanical properties. Tensile strength increased from 5.9 to 15.1 MPa when BC content varied from 0 to 30%, while elongation at break decreased significantly.

  19. Physical stability and moisture sorption of aqueous chitosan-amylose starch films plasticized with polyols

    DEFF Research Database (Denmark)

    Cervera, Mirna Fernández; Karjalainen, Milja; Airaksinen, Sari

    2004-01-01

    The short-term stability and the water sorption of films prepared from binary mixtures of chitosan and native amylose maize starch (Hylon VII) were evaluated using free films. The aqueous polymer solutions of the free films contained 2% (w/w) film formers, glycerol, or erythritol as a plasticizer...... in the crystallinity of the films are evident within a 3-month period of storage, and the changes in the solid state are dependent on the plasticizer and storage conditions. When stored at ambient conditions for 3 months, the aqueous chitosan-amylose starch films plasticized with erythritol exhibited a partly...

  20. 木薯抗性淀粉的酶法制备研究%Resistant Starch of Cassava Preparation by Enzymatic Hydrolysis

    Institute of Scientific and Technical Information of China (English)

    刘婷; 林莹; 古碧; 谭瑶瑶; 查春月; 吴亨

    2012-01-01

    Thermostable a-amylase or pullulanase was used for enzymatic hydrolysis of cassava starch, resistant starch yield of indicators to investigate the enzymatic hydrolysis kinetics of the process of its preparation. The results showed that resistant starch (RS) content was increased first and then less, with the increasing amount of enzyme thermostable a-amylase. RS content was up to 9.13% when the amount of enzyme was 30 U/g of starch reacted 10 min. RS content was increased first and then decreases with increasing degree of hydrolysis DE value trends, and the RS content was up to 9.13% when the DE value was 0.32. Pullulanase hydrolysis of cassava starch hydrolysis curve was followed a reaction equation. The RS content was up to 10.42% when the amount of enzyme was 4U/g of starch roled for 4 h, by that time the debranching degree was 28.51%. RS were significantly increased in the use of both thermostable a-amylase and pullulanase, which would improve the efficiency of preparation of the RS to the theoretical basis by used the complex enzyme.%以木薯淀粉为原料,使用耐高温α-淀粉酶或普鲁兰酶进行酶解,以抗性淀粉得率为指标探讨其制备过程的酶解动力学。结果表明利用耐高温α-淀粉酶制备抗性淀粉(KS),其RS含量随酶用量先增后减,在酶用量30U/g淀粉作用10min抗性淀粉含量达最高为9.13%;RS含量随水解程度DE值的增大呈先增后减趋势,DE值为0.32时抗性淀粉含量最高为9.13%;木薯淀粉的普鲁兰酶水解曲线遵循一级反应方程,在添加酶量为4U/g淀粉作用时间为4h,脱支度为28.51%时抗性淀粉含量达最高10.42%。耐高温α-淀粉酶和普鲁兰酶均能使抗性淀粉含量显著增加,这将为使用复合酶制备抗性淀粉提高其效率奠定理论基础。

  1. Energetic potential of biogas produced from cassava starch wastewater using a pilot scale two-stage anaerobic biodigester; Potencial energetico do biogas gerado no tratamento de aguas residuarias de fecularias em sistema piloto de biodigestao anaerobia com separacao de fases

    Energy Technology Data Exchange (ETDEWEB)

    Feiden, Armin [Universidade Estadual do Oeste do Parana (UNIOESTE), Marechal Candido Rondon, PR (Brazil). Centro de Ciencias Agrarias]. E-mail: armin_feiden@yahoo.com.br; Cereda, Marney Pascoli [UNESP, Botucatu, SP (Brazil). Centro de Raizes Tropicais

    2003-06-01

    Cassava starch is extracted in more of 70 units in west of Parana state, South of Brazil. Near the border of the Parana river there is a big concentration of this type of industry. The cassava starch extraction generates a great quantity of wastewater. The aim of this work was to evaluate the energetic potential of biogas generated in the anaerobic treatment of cassava. The pilot reactors were located at a cassava processing factory, with cassava roots grauding capacity of 250 metric ton day{sup -1} at the parallel 24 deg 09'18'' South latitude and meridian 54 deg 09'26'' West longitude of Grw. The treatment pilot system was consisted of two settling tanks with 500 L each, connected in series, followed by a two-stage anaerobic biodigester reactor. The acidogenic reactor had a capacity of 1,000 L and the methanogenic had a capacity of 3,000 L. The experiment was conducted at temperatures ranging from 23.9 deg C to 27.7 deg C, with a annual average of 25.8 deg C. It was not used the addition of nutrients nor pH correction. The best results were obtained at a flow rate of 901 L d{sup -1} with a TOC (total organic carbon) loading rate of 0.565 g L{sup -1} d{sup -1} and COD (chemical oxygen demand) of 2.49 g L{sup -1} d{sup -1}, and a hydraulic residence time of 4.4 days. At this loading rate, the system had an average biogas yield of 3.975 L L{sup -1} wastewater 0.895 L L{sup -1} reactor day{sup -1}, and 0.391 L g{sup -1} TOC removed. The net biogas yield was 16.10 m{sup 3} ton{sup -1} cassava roots processed, with 28.65% CO{sub 2}. By calculation it was found that the biogas production is enough to supply 30% of the heat necessity to steam production of the industry, 100% of the heat necessity of direct drying of cassava starch, or 50% of the general total electricity need of the factory. (author)

  2. Hydrophobic corn starch thermoplastic films produced by plasma treatment.

    Science.gov (United States)

    Bastos, Daniele C; Santos, Anastácia E F; da Silva, Monica L V J; Simão, Renata A

    2009-07-01

    Polymer coating technology is currently an important field in science as it can lead to final products with enhanced characteristics characterized by desired bulk and surface properties. Low power plasmas can induce the polymerization of a precursor gas on the substrate surface as well as introduce functional groups under specific plasma conditions. In the present work, we studied the possibility of reducing water sensitivity of corn starch films by sulfur hexafluoride (SF(6)) plasma treatment. Confocal laser microscopy as well as atomic force microscopy was used to observe the main surface modifications and results indicated starch cross-linking. Fluoride was incorporated to the surface and the relationship between fluoride and sulfur incorporation to the surface was very much dependent on plasma power. Results indicate that fluoride could be preferentially incorporated on polymeric surfaces at -100V self-bias and the overall surface morphology determined the measured contact angle. The dynamic behavior of surface contact angle was observed to be very much dependent on the treatment time and force-distance curves were used to further characterize the chemical surface modifications locally. Optimized treatment conditions led to water contact angles up to 130 degrees . Even after being in contact with water for 10min, surfaces remained hydrophobic, presenting contact angles over 100 degrees .

  3. Utilization of starch films plasticized with urea as fertilizer for improvement of plant growth.

    Science.gov (United States)

    Rychter, Piotr; Kot, Marta; Bajer, Krzysztof; Rogacz, Diana; Šišková, Alena; Kapuśniak, Janusz

    2016-02-10

    The utilization of starch films, obtained by extrusion of potato starch with urea as plasticizer, for the fertilization of plants has been undertaken. Release rate of urea from the starch films was conducted in water conditions. The molecular weight distribution, surface erosion and weight loss of the starch samples have been determined. The evaluation of efficiency of urea as a fertilizer in the process of release from the starch films was performed under laboratory conditions based on the plant growth test proposed by OECD 208 Guideline and the PN-ISO International Standard using oat and common radish. Although among extruded starch-based films, those that contain the highest amount of fertilizer hold the most promise for a delayed release system, the time of release of fertilizer from obtained films in undertaken study was not satisfactory. All the same, in the present study effort has been made to utilize extruded samples as a fertilizer for agriculture or horticulture purposes. Urea-plasticized starch was successfully used as a fertilizer. Plant growth assessment, including determination of such parameters as fresh and dry matter of plants and their visual evaluation, has proved the stimulating effect of using extruded films on the growth and development of cultivated plants.

  4. Structural and Digestion Properties of Soluble-, Slowly Digestible and Resistant Maltodextrin from Cassava Starch by Enzymatic Modification

    DEFF Research Database (Denmark)

    Sorndech, Waraporn

    to produce slowly digestible and resistant maltodextrin structures. Well-defined ratios of amylose only-barley starch (AO) and waxy maize starch (WX) with non-granular AO content varied from 0 to 100% were used as a substrate. For only BE catalysis, an increase rate of α-1,6 linkage formation for the 0% AO....... The combination of BEAMBE produced more resistant α-glucan products as compared to BE alone. The high amylose starch showed potential to apply as a raw material for enzymatic modification to produce slowly- and indigested dextrin. Slowly and resistant maltodextrin conferring isomaltooligosaccharides (IMO...

  5. Properties of dry film lubricants prepared by spray application of aqueous starch-oil composites

    Science.gov (United States)

    Aqueous dispersions of starch-soybean oil (SBO) and starch-jojoba oil (JO) composites, prepared by excess steam jet cooking, form effective dry film lubricants when applied as thick coatings to metal surfaces by doctor blade. This application method necessitates long drying times, is wasteful, requ...

  6. Oxidized potato starch based thermoplastic films : Effect of combination of hydrophilic and amphiphilic plasticizers

    NARCIS (Netherlands)

    Niazi, Muhammad Bilal Khan; Broekhuis, Antonius A.

    2016-01-01

    Different combinations of hydrophilic (glycerol and water) and amphiphilic (isoleucine) plasticizers were studied in the production of thermoplastic starch (TPS) powders and films from oxidized potato starch. All powder samples had an irregular and shrivelled morphology. In all mixtures containing i

  7. Effect of the incorporation of antimicrobial/antioxidant proteins on the properties of potato starch films.

    Science.gov (United States)

    Moreno, Olga; Atarés, Lorena; Chiralt, Amparo

    2015-11-20

    Glycerol plasticized potato starch films containing bioactive proteins (lactoferrin (LF) and/or lysozyme (LZ), at 0.1 and 0.2 ratio with respect to starch) were obtained by casting method and characterized as to their microstructural, thermal and physical (water content, mechanical, water and oxygen barrier, optical) properties. The bioactive properties, named antioxidant and antimicrobial, of the proteins and the films were also characterized. The incorporation of proteins affected the structural and physical properties of potato starch films, while modifying their thermal behavior and increasing the glass transition temperature. Both proteins showed a certain degree of compatibility with starch chains through the bond formations (increase in Tg), while a part is separated and migrates to the film surface. Their incorporation, especially that of lactoferrin, greatly increased the film's brittleness, regardless of the films water content, although they enhance the water vapor and oxygen barrier properties, whatever the age of the film. Protein also reduced the film's transparency and gloss, while lactoferrin induced color changes. The thermal degradation of blend films and isolated proteins occurred at temperatures of over 250°C, which means that blend starch films can be thermoprocessed, according to their thermoplastic properties and following the usual practices of the plastics industries. A synergistic antimicrobial action against Escherichia coli and coliforms was observed when both LZ and LF were simultaneously applied. Both of these exhibited antioxidant capacity.

  8. Biscoitos de polvilho azedo enriquecidos com fibras solúveis e insolúveis Fermented cassava starch biscuits enriched with soluble and insoluble fibers

    Directory of Open Access Journals (Sweden)

    Flavio Martins Montenegro

    2008-12-01

    Full Text Available O presente trabalho avaliou a utilização de farelo de trigo e polidextrose como fontes de fibra no enriquecimento de biscoitos de polvilho. Utilizou-se a Metodologia de Superfície de Resposta para verificar a influência da adição destes ingredientes nos parâmetros de qualidade dos biscoitos. As respostas avaliadas do planejamento experimental fatorial completo 2² foram o volume específico, a dureza instrumental, a umidade e a cor - parâmetros L, a* e b*. Para as respostas: volume específico e dureza instrumental, todos os fatores foram significativos, a 95% de confiança, com R² = 0,9307 e 0,8091, respectivamente. Pela análise das superfícies geradas, pode-se observar que o farelo de trigo e a polidextrose reduziram o volume específico e o farelo teve maior efeito no aumento da dureza. A substituição de polvilho azedo por farelo de trigo e polidextrose nas proporções de 1,5 e 5%, respectivamente, gerou uma amostra rica em fibras, com 6,23% de fibra alimentar (calculado teoricamente, sem prejuízo considerável para as características de expansão e dureza, e com boa aceitação sensorial.This work evaluated the use of wheat bran and polidextrose as fiber sources to enrich fermented cassava starch biscuits. The Response Surface Methodology was used to verify the influence of the addition of these fiber sources on the quality parameters of the biscuits. The responses of the 2² central composite rotational experimental design that were evaluated were specific volume, hardness, and moisture and color - parameters L, a*, and b*. For the specific volume and hardness responses, all factors were significant: 95% confidence level, with R² of 0.9307 and 0.8091, respectively. Analyzing the surfaces obtained it could be observed that the wheat bran and polidextrose reduced the specific volume and the wheat bran had a greater effect in increasing hardness. The substitution of fermented cassava starch by wheat bran and polidextrose in

  9. 交联羧甲基玉米淀粉和交联酯化木薯淀粉的制备与性质研究%Study on preparation and properties of cross-linked carboxymethyl corn starch and cross-linked esterified cassava starch

    Institute of Scientific and Technical Information of China (English)

    史娟; 杨海涛

    2011-01-01

    The optimum synthesis conditions of the cross-linked carboxymethyl corn starch and cross-linked esterified cassava starch and the key factors affecting the degree of substitution were studied. The physical properties of the two kinds of composite-modified starch, such as freeze-melt stability, light transmissivity, expansibility, were determined. The results showed that the freeze-melt stability, light transmissivity, expansibility of composite-modified starch all improved compared to the n-ative starch,and the cross-linked esterified cassava starch could be used in polluted water with better flocculation effect.%研究了制备交联羧甲基玉米淀粉和交联酯化木薯淀粉的最佳工艺条件及影响取代度的关键因素,并测定了两种复合变性淀粉的冻融稳定性、透光率、膨胀度等特性.结果表明:两种复合变性淀粉的冻融稳定性、膨胀度、透光率等性能均优于原淀粉;交联酯化木薯淀粉具有良好的絮凝效果可用于污水处理.

  10. Effects of pH and Salts on Physical and Mechanical Properties of Pea Starch Films.

    Science.gov (United States)

    Choi, W S; Patel, D; Han, J H

    2016-07-01

    To identify the significant contribution of intermolecular hydrogen bonds of starch molecules to the film structure formation, pH of film-forming solutions was adjusted and also various salts (NaCl, CaCl2 , CaSO4 , and K2 SO4 ) were mixed into the glycerol-plasticized pea starch film. The film made from pH 7 possessed the highest tensile strength-at-break (2 times) and elastic modulus (4 to 15 times) and the lowest elongation-at-break compared with those of the films made from acid and alkali environments. The pH 7 film also has the highest film density and the lowest total soluble matter. At the level of 0.01 to 0.1 M of CaSO4 and 0.1 M of K2 SO4 in a kilogram of starch, the water solubility of the film increased, while chloride salts slightly lowered the solubility. NaCl and CaSO4 reduced water vapor permeability (WVP), while CaCl2 slightly increased WVP at 0.01 and 0.06 M concentrations, and K2 SO4 significantly increased WVP at 0.03 and 0.15 M. Presence of salts increased tensile strength (5 to 14 times than the control films) and elastic modulus (35 to 180 times) of starch film at 0.01 to 0.03 M of CaSO4 and K2 SO4 . Elongation-at-break increased significantly as salt concentration increases to an optimal level. However, when the concentration exceeded above the optimal level, the E of starch films decreased and showed no significant difference from the control film. Overall, the addition of salts modified physical and mechanical properties of pea starch films more than pH adjustment without any salt addition.

  11. Cross-linking reaction kinetics of non-crystalline cassava starch in middle and high temperature wet processes%非晶化木薯淀粉交联反应动力学

    Institute of Scientific and Technical Information of China (English)

    罗明辉; 邓燕芳; 卢龙

    2013-01-01

    以非晶化木薯淀粉为原料,通过湿法交联合成淀粉磷酸酯,研究了非晶化木薯淀粉交联反应动力学过程,计算出表观活化能 Ea,讨论了不同温度对交联反应速率的影响。通过与木薯原淀粉湿法交联对比,研究了非晶化处理对淀粉后续反应的影响。结果表明,非晶化处理后,淀粉交联反应的反应取代度和反应程度均提高,表观活化能降低了23%,反应活性得到大大提高。%The starch diphosphate was synthesized by non-crystalline cassava starch through wet process. The influence of temperature on reaction rate was discussed.The kinetics and apparent activation energy of non-crystalline cassava starch in cross-linking reaction were studied.Compared with raw cassava starch,the influence of non-crystallization on consequent reaction was studied.The results showed the degree of sub-stitution and extent of reaction were both increased after non-crystallization,the apparent activation energy was descended by 23%,and the reaction activity was improved.

  12. Synthesis of Superabsorbent Polymer of Cassava Starch Grafting Acrylic Acid%木薯淀粉-丙烯酸接枝共聚合成高吸水性树脂

    Institute of Scientific and Technical Information of China (English)

    樊红日; 张立颖; 黎洪; 尹丽

    2011-01-01

    [ Objective] The research aimed to study the synthesis of superabsorbent polymer by cassava starch. [ Method] Using acrylic acid and cassava starch as raw material, ammonium persulfate and anhydrous sodium sulfite as initiator, superabsorbent polymer was synthesized by aqueous solution polymerization. The effect of monomer-starch ratio, reaction temperature, reaction time, acrylic acid and its neutralization degree and the initiators dosage on the water absorption of the product were investigated. [ Result ] Water absorbency in deionized water and salt water of 0.9% NaCl were 1 844 g/g and 224 g/g respectively at room temperature within 1 h. [ Conclusion ] The study provided scientific basis for preparing superabsorbent polymer with acrylic acid and cassava starch.%[目的]研究木薯淀粉合成高吸水性树脂.[方法]以木薯淀粉和丙烯酸单体为原料,过硫酸铵-亚硫酸钠为引发剂,通过水溶液聚合法制得淀粉基高吸水性树脂.考察了淀粉与单体配比、反应温度、反应时间、中和度和引发剂用量等因素对产品吸水率的影响.[结果]得出产品在室温下1 h内吸去离子水1 844 g/g、0.9%NaCl盐水224 g/g.[结论]该研究为以木薯淀粉与丙烯酸为原料制备高吸水树脂提供科学依据.

  13. Growth kinetics of Saccharomyces cerevisiae in batch and fed-batch cultivation using sugarcane molasses and glucose syrup from cassava starch.

    Science.gov (United States)

    Win, S S; Impoolsup, A; Noomhorm, A

    1996-02-01

    Growth kinetics of Saccharomyces cerevisiae in glucose syrup from cassava starch and sugarcane molasses were studied using batch and fed-batch cultivation. The optimum temperature and pH required for growth were 30 degrees C and pH 5.5, respectively. In batch culture the productivity and overall cell yield were 0.31 g L-1 h-1 and 0.23 g cells g-1 sugar, respectively, on glucose syrup and 0.22 g L-1 h-1 and 0.18 g cells g-1 sugar, respectively, on molasses. In fed-batch cultivation, a productivity of 3.12 g L-1 h-1 and an overall cell yield of 0.52 g cells g-1 sugar were achieved in glucose syrup cultivation and a productivity of 2.33 g L-1 h-1 and an overall cell yield of 0.46 g cells g-1 sugar were achieved in molasses cultivation by controlling the reducing sugar concentration at its optimum level obtained from the fermentation model. By using an on-line ethanol sensor combined with a porous Teflon tubing method in automating the feeding of substrate in the fed-batch culture, a productivity of 2.15 g L-1 h-1 with a yield of 0.47 g cells g-1 sugar was achieved using glucose syrup as substrate when ethanol concentration was kept at a constant level by automatic control.

  14. PREPARATION AND CHARACTERIZATION OF CO-PROCESSED EXCIPIENT-PREGELATINIZED CASSAVA STARCH PROPIONATE AS A MATRIX IN THE GASTRORETENTIVE DOSAGE FORM

    Directory of Open Access Journals (Sweden)

    Junaedi

    2011-11-01

    Full Text Available The gastroretentive dosage form is designed to prolong the gastric residence time of the drug delivery system whichalso results in the development of an appropriate excipient. The purpose of this study is to develop and characterize coprocessedexcipient made from carrageenan (kappa-iota = 1:1 and pregelatinized cassava starch propionate (PCSP inratios of 1:1, 1:2, and 1:3. PCSP was prepared with propionic anhydride in an aqueous medium. The product was mixedwith carrageenan (kappa-iota = 1:1, as well as characterized physicochemical and functional properties. The coprocessedexcipient was then used as a mucoadhesive granule and floating tablet. The USP Basket was selected toperform the dissolution test of the granules in HCl buffer (pH 1.2 and distilled water for 8 hours each. Mucoadhesiveproperties were evaluated using bioadhesive through a vitro test and wash-off test. As for the floating tablet, the USPPaddle was selected to perform the dissolution test of the tablets in 0.1 N HCl for 10 hours. The floating lag time andfloating time were tested in 0.1 N HCl for 24 hours. The result of these studies indicated that co-processed excipientcarrageenan-PCSP can retard dosage form in gastric and drug controlled release, thus making it a suitable material forthe gastroretentive dosage form.

  15. Characterization of films made with chayote tuber and potato starches blending with cellulose nanoparticles.

    Science.gov (United States)

    Aila-Suárez, Selene; Palma-Rodríguez, Heidi M; Rodríguez-Hernández, Adriana I; Hernández-Uribe, Juan P; Bello-Pérez, Luis A; Vargas-Torres, Apolonio

    2013-10-15

    The aim of this study was to characterize chayotextle starch films reinforced with cellulose (C) and cellulose nanoparticle (CN) (at concentrations of 0.3%, 0.5%, 0.8% and 1.2%), using thermal, mechanical, physicochemical, permeability, and water solubility tests. C was acid-treated to obtain CN. The films were prepared by casting; potato starch and C were used as the control. The solubility of the starch films decreased with the addition of C and CN compared with its respective film without C and CN. No statistical difference (α=0.05) was found in the films added with different concentrations of C and CN. In general, the mechanical properties were improved with the addition of C and CN, and higher values of tensile strength and elastic modulus were determined in the films reinforced with CN. The melting temperature and enthalpy increased with the addition of C and CN, and the values of both thermal parameters were higher in the films with CN than with C; the enthalpy value of the film decreased when the concentration of C or CN increased in the composite. Low concentration of C and CN is better distributed in the matrix film. The addition of C and CN in the starch films improved some mechanical, barrier, and functional properties.

  16. Effect of growing period on the cassava starch properties of various cassava cultivars%生长期对不同品种(系)木薯淀粉特性的影响

    Institute of Scientific and Technical Information of China (English)

    林莹; 古碧; 李凯; 代道芳

    2011-01-01

    The effect was studied of growing period on the starch properties such as freeze-thaw stability, sediment stability and mean granule size of three cassava cultivars. Freeze-thaw stability was higher and sediment stability was lower in samples harvested at 6th month. The difference of freeze-thaw stability and sediment stability depend on cultivars through the extended growing period. Surface area mean particle size was small and volume mean diameter was large at 6th month. For all cultivars, sediment stability was found to have positively significant correlations with surface area mean particle size. For SE cultivar, sediment stability was positively significant correlated to volume mean particle diameter. For E cultivars, freezethaw stability was negatively significant correlated to surface area mean particle size.%研究生长期对3个品种(SC、E和C)木薯淀粉冻融稳定性、凝沉稳定性和粒径的影响.结果表明,生长期为6个月时,淀粉具有较好的冻融稳定性、较差的凝沉稳定性、较高的体积平均粒径以及较小的表面积平均粒径.相关性分析表明,3个品种木薯淀粉的凝沉稳定性与淀粉表面积平均粒径呈显著正相关,品种SC的淀粉凝沉稳定性与体积平均粒径显著正相关,品种E的冻融稳定性与淀粉表面积平均粒径呈极显著负相关.

  17. 十二烷基苯磺酸木薯淀粉酯微波法制备工艺研究%Preparation technology of dodecyl benzene sulfonic acid cassava starch ester by microwave

    Institute of Scientific and Technical Information of China (English)

    张利伟; 薛行华; 赵法敏; 张永强; 李光

    2013-01-01

    Dodecyl benzene sulfonic acid cassava starch ester was prepared by microwave method with cassava starch as the raw material , sodium dodecyl benzene sulfonate as the esterification agent and sodium hydroxide as the catalyst .The effects of synthetic condition , such as molar ratio ( sodi-um dodecyl benzene sulfonate to glucose unit of cassava starch ) , reaction time , incubated tempera-ture and pH value , on the substitution degree were investigated .The best conditions by orthogonal design were the molar ratio of sodium dodecyl benzene sulfonate to cassava at 0.06 , reaction time 5 h and the incubated temperature 80 ℃, at which the degree of substitution was 0.010 0 .FT-IR and XRD revealed the changes in the structure of the esterified starch , and TG analysis also dis-played the decline of the hydrophilic and thermal stability of the esterified starch .%  以木薯淀粉为原料,十二烷基苯磺酸钠为酯化剂,NaOH为催化剂,采用微波法制备十二烷基苯磺酸木薯淀粉酯,并考察其合成的工艺条件。探讨了十二烷基苯磺酸钠与木薯淀粉葡萄糖单元的摩尔比、反应时间、反应温度和pH值对产物取代度的影响,用正交实验分析对制备工艺进行优化,并通过红外、X射线和热重分析表征了酯化淀粉的结构及其热稳定性。结果表明,在十二烷基苯磺酸钠与木薯淀粉葡萄糖单元摩尔比为0.06、反应时间5 h、反应温度80℃和pH为10的条件下制备的十二烷基苯磺酸酯淀粉的取代度最佳,取代度为0.0100。红外和X射线谱图证明了酯化淀粉结构的改变,热重分析表明酯化淀粉亲水性与热稳定性有所下降。

  18. Synthesis, characterization and antibacterial activity of biodegradable starch/PVA composite films reinforced with cellulosic fibre.

    Science.gov (United States)

    Priya, Bhanu; Gupta, Vinod Kumar; Pathania, Deepak; Singha, Amar Singh

    2014-08-30

    Cellulosic fibres reinforced composite blend films of starch/poly(vinyl alcohol) (PVA) were prepared by using citric acid as plasticizer and glutaraldehyde as the cross-linker. The mechanical properties of cellulosic fibres reinforced composite blend were compared with starch/PVA crossed linked blend films. The increase in the tensile strength, elongation percentage, degree of swelling and biodegradability of blend films was evaluated as compared to starch/PVA crosslinked blend films. The value of different evaluated parameters such as citric acid, glutaraldehyde and reinforced fibre to starch/PVA (5:5) was found to be 25 wt.%, 0.100 wt.% and 20 wt.%, respectively. The blend films were characterized using Fourier transform-infrared spectrophotometry (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA/DTA/DTG). Scanning electron microscopy illustrated a good adhesion between starch/PVA blend and fibres. The blend films were also explored for antimicrobial activities against pathogenic bacteria like Staphylococcus aureus and Escherichia coli. The results confirmed that the blended films may be used as exceptional material for food packaging.

  19. Preparation and Characterization of Potentially Antimicrobial Polymer Films Containing Starch Nano- and Microparticles

    Directory of Open Access Journals (Sweden)

    Paulius Pavelas DANILOVAS

    2014-09-01

    Full Text Available The forming conditions of biodegradable polymer films containing iodine-modified starch particles as well as the properties of the obtained films were investigated. Cationic cross-linked starch microparticles and cationic starch nanoparticles were dispersed in cellulose acetate and hydroxyethyl cellulose solution, respectively, and composite films were spin-casted. The obtained films were characterized and their mechanical properties were assessed. The cellulose acetate solution has been found to be an appropriate matrix for the dispersion of dry modified starch microparticles, but not in the case of nanoparticles. Starch nanoparticles were obtained in an aqueous medium, and the mechanical properties of the formed cellulose acetate films are significantly reduced by water present in the casting solution. It has been estimated that a fairly high amount of nanoparticles (18 wt% can be immobilized into films of water-soluble hydroxyethyl cellulose without markedly affecting the mechanical properties of the films. DOI: http://dx.doi.org/10.5755/j01.ms.20.3.5426

  20. Production and characterization of cellulose reinforced starch (CRT) films.

    Science.gov (United States)

    Sudharsan, K; Chandra Mohan, C; Azhagu Saravana Babu, P; Archana, G; Sabina, K; Sivarajan, M; Sukumar, M

    2016-02-01

    Starch from Tamarind seed is considered to be a nonedible and inexpensive component, with many industrial applications. Extraction and characterization of tamarind seed starch was carried out for the synthesis of biopolymer. Tamarind seeds were collected, cleaned and further roasted, decorticated, and pulverized to get starch powder. Total starch content present in each tamarind seed is estimated to be around 65-70%. About 84.68% purified starch can be recovered from the tamarind seed. Defatted Tamarind seed starch has an amylose content of 27.55 wt.% and 72.45 wt.% of amylopectin. Morphological (SEM) and X-ray diffraction were used to evaluate crystallinity. Likewise, TGA and DSC of starch have also been analyzed. Thermal properties of starch obtained from tamarind seeds showed good thermal stability when compared to other starch sources such as Mesquite seed and Mango kernel. This study proved that the tamarind seed starch can be used as a potential biopolymer material. Thermo-stable biofilms were produced through initial optimization studies. Predictive response surface quadratic models were constructed for prediction and optimization of biofilm mechanical properties. Correlation coefficient values were calculated to me more than 0.90 for mechanical responses which implies the fitness of constructed model with experimental data.

  1. Effect of cellulose nanocrystals and gelatin in corn starch plasticized films.

    Science.gov (United States)

    Alves, J S; dos Reis, K C; Menezes, E G T; Pereira, F V; Pereira, J

    2015-01-22

    Cellulose at the nanoparticle scale has been studied as a reinforcement for biodegradable matrices to improve film properties. The goal has been to investigate the properties of starch/gelatin/cellulose nanocrystals (CNC) films. Eleven treatments were considered using RCCD (rotatable central composite design), in addition to four control treatments. For each assay, the following dependent variables were measured: water vapor permeability (WVP), thickness, opacity and mechanical properties. The microstructure and thermal properties of the films were also assessed. Increases in gelatin and CNC concentrations lead to increases in film thickness, strength and elongation at break. The films containing only gelatin in their matrix displayed better results than the starch films, and the addition of CNC had a positive effect on the assessed response variables. The films exhibited homogeneous and cohesive structures, indicating strong interactions between the filler and matrix. Films with low levels of gelatin and CNC presented the maximum degradation temperature.

  2. Edible Film Making of Starch Canna Tuber (Canna Edulis Kerr and Aplication to Packaging Galamai

    Directory of Open Access Journals (Sweden)

    Hafnimardiyanti Hafnimardiyanti

    2014-01-01

    Full Text Available Canna (Canna edulis Kerr was a tuber that had a high carbohydrate content so canna had excellent prospects to develop into edible film. The purpose of this study was to make edible film of canna starch, knowing storability galamai was packed with edible film and determine the level of preference panelists through organoleptic tests. In this research, manufacture of edible films with various concentrations of canna starch 2%, 3%, 4% and the use of plasticizer (glycerol 1%, 2% and 3% with 100 ml of water as a solven and then applied to galamai as a packaging. Of research on edible film get the best that was produced with the use of starch canna tuber 3% with the addition of 1% glycerol, wherein the edible film produced slightly thick and easily opened from the mold. Of organoleptic test showed that galamai packed with edible films of canna tuber starch 3% was the highest scores of the panelists with categories like. From the Friedman test showed that all three variations of the edible film packaging galamai, provide diversity to the test variable organoleptic (color, aroma, texture and flavor. Galamai was packed with edible film could be stored for 1 month.

  3. 热塑性木薯淀粉回生过程的结构与性能研究%Study on Structure and Property of Thermoplasticitc Cassava Starch in Retrogradation Process

    Institute of Scientific and Technical Information of China (English)

    范丽兰; 刘钰馨; 莫羡忠; 李建鸣; 李雨露; 汤立洁

    2016-01-01

    Thermoplastic cassava starch materials was prepared with cassava starch as raw material and glycerin as plasticizer by melting mixing in a torque rheometer. The structures and properties of thermoplastic cassava starch were investigated by differential scanning calorimeter (DSC), polarizing microscope (PLM),Fourier transform infrared spectrometr (FTIR), X ray diffraction (XRD) and thermal gravimetric analysis (TG) during retrogradation process. The results indicated that the melting enthalpy of thermoplastic cassava starch material first increased then decreased over time. It had a highest melting enthalpy when the retrogradation time reached 7d, the number of starch spherulites reached the highest degree and the polarization cross was formed. Through FTIR, when the retrogradation played a main role, infrared absorption peaks had a blue-shift meanwhile hydrogen bonding action were weakened. When the degradation played a main, infrared absorption peaks had a red-shift and hydrogen bonding actions were strengthened. In addition, the crystal type turn from A+V to V in the retrogradation process of thermoplastic cassava starch, and the crystallinity was 40.44% by the calculation of TOPAS. The hydrogen bonding was take place between starch molecules, and made the thermal stability of starch material decreased in the retrogradation process.%以木薯淀粉为原料、甘油为增塑剂,通过转矩流变仪熔融共混制备热塑性木薯淀粉,利用差示扫描量热法(DSC)、偏光显微镜(PLM)、傅立叶红外(FTIR)、X射线衍射(XRD)和热重分析(TG)研究热塑性木薯淀粉材料在回生过程中的结构与性能变化。结果表明,随着回生时间的增加,热塑性木薯淀粉材料的回生焓先增大后减小,当回生时间为7d时达最高;木薯淀粉球晶出现且球晶的数目最多,偏光十字最规整,回生达最大程度。FTIR分析发现,当回生作用占主导地位,氢键作用力减弱

  4. 超声波处理对木薯淀粉糊理化性质的影响%Effects of Ultrasonic Treatment on Properties of Cassava Starch Paste

    Institute of Scientific and Technical Information of China (English)

    汪树生; 苏玉春; 陈光

    2012-01-01

    Cassava starch paste was ultrasonic-treated and the effects of ultrasonic on paste properties were determined. The results indicated that a 5-minuete ultrasonic treatment decreased the viscosity of cassava starch paste, but increased anti-shearing ability.Short time ultrasonic treatment increased transparency of the paste effectively, from 10.05 up to 38.5 after treated for 1.5 minuets. The retrogradation trend decreased after ultrasonic treatment and retrogradation intensity increased within 1.5 minutes, above which similar impact was found. Ultrasonic treatment was an effective modified method to alter the properties of cassava starch paste.%利用超声波对木薯淀粉糊液进行处理,研究超声作用对糊液特性的影响.结果表明:超声波处理降低了木薯淀粉糊液的粘度,提高了抗剪切作用能力,处理5min效果最明显;短时间的超声作用能有效改善淀粉糊液的透明度,处理1.5 min透明度最高,由原来的10.05上升到38.5;超声处理能延缓淀粉糊液的凝沉趋势,加强凝沉的强度,处理时间超过1.5 min后,效果接近.超声波处理可以作为一种有效的改变淀粉糊液特性的途径应用于淀粉的变性处理中.

  5. Properties of cast films made of chayote (Sechium edule Sw.) tuber starch reinforced with cellulose nanocrystals

    Science.gov (United States)

    In this study, cellulose (C) and cellulose nanocrystals (CN) were blended with chayote tuber (Sechium edule Sw.) starch (CS) in formulations cast into films. The films were conditioned at different storage temperatures and relative humidity (RH), and analyzed by mechanical tests, X-ray diffraction, ...

  6. In-situ lamination of starch-based baked foam articles with degradable films

    Science.gov (United States)

    A technique for making biodegradable food service packaging comprised of a starch/fiber core and a biodegradable film laminate is described. The biodegradable films were made of polylactic acid (PLA), polybutylenesuccinate/terephthalate (PBST), rubber latex and polybutyleneadipate/terephthalate (PB...

  7. Effects of Different Added Substances on the Rheological Properties of Hydroxypropyl Cassava Starch Paste%不同添加物对羟丙基木薯淀粉流变特性的影响

    Institute of Scientific and Technical Information of China (English)

    胡珊珊; 王颉; 孙剑锋; 刘亚琼; 牟建楼; 王娜

    2012-01-01

    淀粉糊流变特性是影响淀粉类食品加工品质的主要因素.利用流变仪测定了不同添加物质对羟丙基木薯淀粉流变特性的影响,结果表明:添加不同的物质均未改变羟丙基木薯淀粉糊的流体类型,各流变参数经Herschel-Bulkley模型进行拟合,拟合系数接近1.单甘酯、食盐、柠檬酸使羟丙基木薯淀粉糊的剪切应力不同程度降低,黏稠系数减小,流变特性指数增加;蔗糖酯、酪朊酸钠、黄原胶、CMC、瓜尔豆胶、蔗糖使羟丙基木薯淀粉糊的剪切应力明显提高,黏稠系数增加,流变特性指数减小.%The rheological property of starch pastes is an important influencing factor during the processing of starchy food. The effect of different added substances on the rheological properties of hydroxypropyl cassava starch was measured by rheometer. The results showed that: the fluid type of hydroxypropyl cassava starch was not altered by the different added substance, and the fitting coefficient closed to 1 as the rheological parameters was fitted by the Her-schel - Bulkley model. Monoglycerides,salt and citric acid had the same effect on the hydroxypropyl cassava starch, which made the shear stress reduced to varying degrees, the consistency index decreased and the flow index increased. Contrary to that,sucrose esters,sodium caseinate,xanthan gum,CMC,guar gum made the shear stress significantly increased, the consistency index increased and flow index decreased. The results of this study offered valuable references for the further processing of hydroxypropyl cassava starchy products.

  8. Study on Hydrolysis Process of Cassava Starch Used for Microbial Lipid Fermentation%用于微生物油脂发酵的木薯淀粉水解工艺的优化

    Institute of Scientific and Technical Information of China (English)

    张志斌; 颜日明; 曾庆桂; 汪涯; 朱笃

    2012-01-01

    In order to improve the lipid production of cassava starch, the process of cassava starch hydrolysis (CSH) was optimized using orthogonal experimental design and Uniform design. The results showed that the content of α-amylase and glucoamylase and the liquefaction temperature significantly influenced cassava starch amylolysis. The dextrose equivalent value was up to 97.3% when content of α-amylase and glucose amylase and liquefaction tem-perature were 756 u/g, 602 u/g and 92℃ , respectively. While the CSH was used as a carbon source,the biomass and total lipid content of Trichosporon cutaneum were 16.38g/L and 7.22 g/L respectively, which increased by 46. 25% and 41.12% as compared with those using glucose as a carbon source. Therefore, cassava starch hydrolysis, as a novel carbon source, is an ideal route to produce microbial lipid.%为了提高木薯淀粉的发酵产脂能力,采用正交实验和均匀设计法对木薯淀粉酶法水解工艺进行了优化,结果表明d一淀粉酶量、糖化酶量和液化温度对木薯淀粉水解有显著影响。当淀粉酶量为756U/g,糖化酶量为602U/g,液化温度为92℃,其水解DE值达到97.3%。以该水解液进行皮状丝胞酵母B3(rcutaneumB3)油脂发酵时,其生物量和油脂产量分别为16.38g/L和7.22g/L,比葡萄糖作为碳源的生物量和油脂产量高46.25%和41.12%,利用木薯淀粉水解液作为新型发酵碳源生产微生物油脂是一种理想的途径。

  9. A review of the recent advances in starch as active and nanocomposite packaging films

    Directory of Open Access Journals (Sweden)

    Umar Shah

    2015-12-01

    Full Text Available Technological advances have led to increased constraints regarding food packaging due to environmental issues, consumer health concerns, and economic restrictions associated therewith. Hence, food scientists and technologists are now more focused on developing biopolymer packages. Starch satisfies all the principle aspects, making it a promising raw material for edible coatings/films. Starch as a package material has grabbed much attention both at academic as well as industrial levels. Besides this, the role of various plasticizers, polys, sugars, and wetting agents are discussed and their importance in packaging industries. Herein, the role of starch as packaging material and nanofillers/composites is discussed in detail. The review summons a comprehensive and current overview of the widely available information and recent advances in starch film packaging.

  10. Solid Substrate Fermentation of Cassava Peel for Poultry Feed Ingredient

    Directory of Open Access Journals (Sweden)

    Stephanie

    2013-03-01

    Full Text Available Cassava peel which is not used during cassava starch extraction is one of potential resources for animal feed. However, cassava peel has low level protein content, high level crude fiber, and high level of toxic cyanogenic compound. These problems limit the utilization of cassava peel as feed. Solid substrate fermentation using mold may be a solution process to increase its nutritional value and decrease toxic level of cassava peel. In this paper, matters that related with cassava peel fermentation process are subsequently described, namely: (i problems of cassava peel; (ii biodegradation and detoxification process; (iii solid state fermentation methods on cassava peel; (iv nutritional quality of fermented cassava peel; and (v application of fermented cassava peel in poultry feed. The fermented cassava peel application is compared with those of cassava root and waste (onggok. Addition of nitrogen inorganic in the fermentation process increases the mold growth and protein content of the product, while fiber and cyanogenic contents are decreased due to mold degradation activity. The fermentation process may be carried out using only the cassava peel as the substrate or mixed with wheat flour, using indigenous microbes, Aspergillus niger or a white rot fungus, Panus tigrinus as inoculum. As well as fermented cassava root and waste, fermented cassava peel can be used to substitute maize as poultry feed, although it is reported that the optimum substitution in broiler ration is only 10%.

  11. Effects of processing on physical properties of extruded snacks with blends of sour cassava starch and flaxseed flour

    Directory of Open Access Journals (Sweden)

    Camila De Barros Mesquita

    2013-09-01

    Full Text Available The opportunity to supplement common cassava biscuits with a product of higher nutritional value meets consumer expectations. In this work it was studied the effects of process parameters and flaxseed addition on physical properties of expanded snacks. Extrusion process was carried out using a single screw extruder in a factorial central composite rotatable design with four factors: flaxseed flour percentage (0-20%, moisture (12-20%, extrusion temperature (90-130 °C and screw speed (190-270. The effect of extrusion variables was investigated in terms of expansion index, specific volume, water absorption index, water solubility index, color parameters (L*, a* ,b* and hardness. The data analysis showed that variable parameters of the extrusion process and flaxseed flour affected physical properties of puffed snacks. Among the experimental conditions used in the present study, expanded snack products with good physical properties can be obtained under the conditions of 10% flaxseed flour, 230 rpm screw speed, temperature of 90 °C and moisture of 12%.

  12. Produção de snacks extrusados à base de polvilho doce e fibra de laranja Production of extruded snacks from cassava starch and orange fiber

    Directory of Open Access Journals (Sweden)

    Magali Leonel

    2010-06-01

    Full Text Available Este trabalho teve por objetivo avaliar o efeito da umidade, temperatura de extrusão e rotação da rosca na produção de produtos extrusados expandidos com a utilização do polvilho doce e da polpa de laranja desidratada como matéria-prima. O processo seguiu delineamento central composto rotacional com três fatores, totalizando 15 tratamentos (oito pontos fatoriais, seis pontos axiais e um ponto central com seis repetições. Os produtos obtidos foram caracterizados quanto ao índice de expansão (IE, ao volume específico (VE, ao índice de solubilidade em água (ISA e à cor (L*, a* e b*. Os resultados mostraram efeito das condições operacionais do processo sobre as características físicas dos produtos, e produtos claros com maior expansão e menor solubilidade em água foram obtidos nas condições mais elevadas de temperatura (80-90°C, condições intermediárias de umidade (16% e rotação da rosca (218rpm.This research aimed to evaluate the effect of moisture, extrusion temperature and screw speed in the production of flax snacks using as raw material cassava starch and dehydrated orange pulp. The process followed the central composite rotational design to three factors, totaling 15 treatments (8 factorial points, 6 star points and 1 center point with 6 repetitions. The products obtained were characterized for expansion rate, specific volume, water solubility index and color (L*, a* and b*. The results showed the effect of operational conditions on the physical characteristics of products, and clear products with larger expansion and lower water solubility index were obtained in conditions of the highest temperature (80-90°C and moisture (16% and intermediate screw speed (218rpm.

  13. Effects of Dissolved Oxygen Tension and Ammonium Concentration on Polyhydroxybutyrate Synthesis from Cassava Starch by Bacillus cereus IFO 13690

    Directory of Open Access Journals (Sweden)

    Margono .

    2015-11-01

    Full Text Available generated by an Adobe application 11.5606 Attempting to get low price of raw material for producing polyhydroxybutyrate is always studied. Tapioca starch is one of the raw material with low price. The objective of this research was to study the effects of initial ammonium concentration and dissolved oxygen tension (doT on producing PHB by Bacillus cereus IFO 13690 with tapioca starch as the carbon source. This fermentation was carried out in 5 L fementors with a 2 L working volume, temperature of 30 oC, and agitation of 500 rpm. The pH medium was controlled at 5.6 after it came down from the initial pH of 6.8. Meanwhile, the initial doT was 100 % air saturation and also came down to and maintained at doT of experiment, i.e. 1 , 5 , or 10 % air saturation. The best result was obtained when the initial ammonium concentration was 5 g/L and the doT value maintained at 5 % air saturation. By this conditions, the cell growth reached 5,457 g cell dry weight/L containing PHB of 2.42 % cell dry weigh after 29 hours fermentation. Normal 0 36 false false false

  14. Effect of cross linking of PVA/starch and reinforcement of modified barley husk on the properties of composite films.

    Science.gov (United States)

    Mittal, Aanchal; Garg, Sangeeta; Kohli, Deepak; Maiti, Mithu; Jana, Asim Kumar; Bajpai, Shailendra

    2016-10-20

    Barley husk (BH) was graft copolymerized by palmitic acid. The crystalline behavior of BH decreased after grafting. Poly vinyl alcohol (PVA)/starch (St) blend film, urea formaldehyde cross linked PVA/St films and composite films containing natural BH, grafted BH were prepared separately. The effect of urea/starch ratio, content of BH and grafted BH on the mechanical properties, water uptake (%), and biodegradability of the composite films was observed. With increase in urea: starch ratio from 0 to 0.5 in the blend, tensile strength of cross linked film increased by 40.23% compared to the PVA/St film. However, in grafted BH composite film, the tensile strength increased by 72.4% than PVA/St film. The degradation rate of natural BH composite film was faster than PVA/St film. Various films were characterized by SEM, FT-IR and thermal analysis.

  15. Modelling of moisture adsorption for sugar palm (Arenga pinnata) starch film

    Science.gov (United States)

    Jatmiko, Tri Hadi; Poeloengasih, Crescentiana D.; Prasetyo, Dwi Joko; Hernawan

    2017-03-01

    Sorption characteristic of food products is important for design, optimization, storage and modelling. Sugar palm starch film with two different plasticizers (sorbitol and glycerol) with varied concentration studied for its adsorption isotherm characteristic. The data of adsorption isotherm fitted with GAB, Oswin, Smith and Peleg models. All models describe the experiment data well, but Peleg model is better than the other models on both sugar palm starch film plasticized with sorbitol and glycerol. Moisture sorption of sugar palm starch increased linearly with plasticizer concentration. A new model by taking account of plasticizer concentration describes the experiment data well with an average of coefficients of determination (R2) 0.9913 and 0.9939 for film plasticized with glycerol and sorbitol respectively.

  16. Studies on Mechanical Properties of Full-Biodegradable Starch-PVA-Polyester Films

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A kind of full-biodegradable film material is discussed in this article. The film material is composed of starch, PVA, degradable polyesters(PHB, PHB-V, PCL) with built plasticizer, a cross-linking reinforcing agent and a wet strengthening agent. It contains a high percentage of starch, costs cheap and is excellent in weather fastness, temperature resistance and waterproof and it could be completely biodegraded. The present paper deals mainly with a new technical route using a new type of electromagnetic dynamic blow molding extruder and some effects on mechanical properties of the system.

  17. Plasticization effect of triacetin on structure and properties of starch ester film.

    Science.gov (United States)

    Zhu, Jie; Li, Xiaoxi; Huang, Chen; Chen, Ling; Li, Lin

    2013-05-15

    The aim of this work was to evaluate the plasticizing effect of triacetin on the structure and properties of starch ester film and further establish the structure-property relationships. The presence of triacetin resulted in multiple structure changes of the film. The mobility of macromolecular chain was increased to form scattered crystallite during the film formation process. The amorphous region was enlarged to contain more triacetin squeezed from crystalline region. The plasticization of triacetin and restriction of crystallite oppositely influenced the mobility of macromolecular chains in different regions. The thermal stability of triacetin changed along with its fluctuant interaction with macromolecules. Comparatively, the enhanced ether bond and the restriction from crystalline regions on the mobility of the amorphous chain consequently improved the thermal stability of the film matrix. The interaction between triacetin and starch ester was essential to film forming but unexpectedly lowered the triacetin stability.

  18. REKAYASA PROSES HIDROLISIS PATI DAN SERAT UBI KAYU (Manihot utilissima UNTUK PRODUKSI BIOETANOL Hydrolysis Process Design of Starch and Cassava (Manihot utilissima Fibers for Bioethanol Production

    Directory of Open Access Journals (Sweden)

    Yuana Susmiati

    2012-05-01

    Full Text Available Ethanol production from cassava (Manihot utilissima usually uses enzymatic process for starch hydrolysis. Enzymatichydrolysis by α-amylase and amyloglucosidase enzymes are not able to convert cassava fibers into sugars. Dilute acid hydrolysis is applied to convert both starch and fibers, which will increase the yield of simple sugars as fermentable sugars and resulting in high ethanol production. In this research there are two steps of dilute acid hydrolysis, first for starch hydrolysis at H SO concentration of 0.1-0.5 M, 5-15 minutes and second for fiber hydrolysis at 0.5-1.0 2 4M H SO , 10-20 minutes, at the same temperature of 121-127 oC and pressure of 1.0-1.5 atm. The disadvantage of acid hydrolysis is the formation of toxic compounds such as hydroxymethyl furfural (HMF which is inhibited yeast fermentation. Therefore, acid hydrolyzates were detoxified with NH OH before use as fermentation substrate. The best starch hydrolysis condition was obtained at 0.4 M H SO  for 10 minutes which gave 257.37 g/l of total sugars, 2 4229.38 g/l of reducing sugars, 89.59 of dextrose equivalent (DE and 0.57 g/l of HMF. While the best fiber hydrolysis performed at 1.0 M H SO  solution for 20 minutes which gave 79.74 g/l of total sugars, 70.88 g/l of reducing sugars, 2 488.99 of DE and 0.0142 g/l of HMF. Single direct acid hydrolysis was the most suitable substrate for yeast fermentationwith the ethanol concentration of 5.7 % (w/v and 30.5 % (w/w of ethanol yield. This result is comparable with enzymatic hydrolysis which gave ethanol yield of 30 % (w/w. ABSTRAK Produksi etanol dari ubi kayu biasanya menggunakan enzim untuk menghidrolisis pati. Hidrolisis secara enzimatismenggunakan enzim α-amilase dan amiloglukosidase tidak mampu mengkonversi serat menjadi gula. Hidrolisis asam  berkonsentrasi  rendah  dilakukan  untuk  mengkonversi  pati  dan  serat,  sehingga  gula-gula  sederhana  yang dapat difermentasi meningkat dan menghasilkan

  19. 处理木薯淀粉废水的厌氧反应器初次启动方法研究%Study on the initial start-up method of anaerobic reactor for treating cassava starch wastewater

    Institute of Scientific and Technical Information of China (English)

    任伯帜; 韦兴浩; 侯保林

    2012-01-01

    对处理木薯淀粉废水的EGSB厌氧反应器初次启动时的接种污泥选择、污泥驯化方法、厌氧反应器控制条件进行研究.当选用木薯酒精厂厌氧发酵污泥作为接种污泥,控制pH在6.8~7.6,VFA<1 000 mg/L,温度在26~28℃时,采用阶段进水驯化方式,经过近100 d的实际运行,成功培养出适应木薯淀粉废水的颗粒污泥,系统COD去除率达86%以上,厌氧反应器启动成功,运行状况良好,处理效果稳定.%everal factors such as the selection of inoculated sludge,method of sludge acclimatization and the condition of the anaerobic reactor control for treating cassava starch wastewater when initially started-up have been studied. When the anaerobic fermented sludge of the cassava alcohol plant is selected as inoculated sludge,its pH should be controlled at 6.8-7.6,VFA<1 000 mg/L,and temperature at 26-28 ℃ ,the influent water acclimatization in phasic mode is used. After running for almost 100 d,the granular sludge that is suitable for cassava starch has successfully been cultivated. Under these conditions,the removing rate of COD could be higher than 86% ,and the anaerobic reactor has started up smoothly and fluently, with stable treatment effect.

  20. 超临界CO2处理对木薯淀粉结构和性质的影响%Effects of supercritical CO2 treatment on structures and properties of cassava starch

    Institute of Scientific and Technical Information of China (English)

    白俊; 李习都; 谢新玲; 张友全

    2016-01-01

    Cassava starch was extracted in different conditions with supercritical carbon dioxide. The morphological characteristics and the gelating properties of the treated starch, such as particle morphology, swelling degree, crystalline structure, viscosity, retrogradation and freeze-thaw stability, were evaluated and compared with native cassava starch by using scanning electron microscope, X-ray diffraction analyzer, Brabender visco-analyser or other methods. As a result, it showed that with the change of the pressure, temperature and time of the treatment, the morphology of the treated starch was not obviously changed, but the swelling degree decreased and the crystallinity increased. It also found that the anti-precipitability of the treated starch gel was strengthened and the freeze-thaw stability reduced. Meanwhile, Brabender viscosity analysis suggested that the gelation temperature of the treated starch could be slightly raised and the peak viscosity of the treated starch gel decreased, while the thermal stability little changed. All the results indicated that thecassava starch molecules could be partially degraded and the ratio of amylose to amylopectin would increase in the process of supercritical treatment, leading to the alteration of some microstructure characteristics and gelating properties of cassava starch.%采用超临界二氧化碳萃取技术在不同条件下处理木薯淀粉,利用扫描电镜(SEM)、X射线衍射仪(XRD)、布拉班德(Brabender)黏度仪等分析手段,考察超临界处理对木薯淀粉颗粒形貌、膨胀度、结晶结构以及淀粉糊黏度、凝沉性、冻融稳定性等的影响。结果表明,随超临界压力、温度、处理时间的变化,样品颗粒外貌无明显改变,但膨胀度降低,结晶度增大;淀粉糊的凝抗性增强,淀粉凝胶冻融稳定性却降低;Brabender黏度分析显示经超临界处理后的淀粉样品糊化温度小幅度升高,糊峰值黏度降

  1. The influence of ionizing radiation on the properties of starch-PVA films

    Directory of Open Access Journals (Sweden)

    Abramowska Anna

    2015-09-01

    Full Text Available The cornstarch: poly(vinyl alcohol (PVA films characterized by the alternating ratio of starch:PVA (100:0, 80:20, 60:40, 40:60, 20:80, and 0:100 and containing 30% of glycerol were prepared by solution casting. The films were irradiated with an absorbed dose of 25 kGy with gamma rays in a vacuum and with fast electrons in the air. The films characterized by a high content of starch appeared stiff, while the films characterized by a high content of PVA were highly flexible. The tensile strength and flexibility, as well as swelling and hydrophilicity, increased with the increase in the PVA content in the films. However, the tensile strength and wetting angle values achieved a minimum at an intermediate composition. It was found that irradiation enables to reduce hydrophilicity of the films accompanied by a decrease in their flexibility. No general conclusion concerning the effect of irradiation on tensile strength and swelling behavior can be derived. An increase in the homogeneity of the films and an increase in the compatibility of their components was found by scanning electron microscopy (SEM. Strong interactions of the starch and the PVA components were discovered by diffuse reflectance spectroscopy. Degradation was found to be the prevailing process occurring in the films under the influence of irradiation. The possible accompanying crosslinking is discussed in terms of the gel content in the samples. Creation of various oxidation products in the films characterized by the modified composition was observed under the influence of irradiation carried out in the air. Basing on the obtained results it can be supposed that the selected starch-PVA compositions might appear useful as packagings of the products predicted for radiation decontamination.

  2. Modulating rheo-kinetics of native starch films towards improved wet-strength

    DEFF Research Database (Denmark)

    Gillgren, Thomas; Blennow, Andreas; Pettersson, Anders J.;

    2011-01-01

    highly different starch types derived from potato and cereal sources of normal and mutant and transgenic backgrounds. A new improved technique was developed to permit the dynamic mechanical analysis of films in the presence of water. It was found that the amylose content was decisive for the mechanical....... Transgenic potato starch with a low content of phosphate displayed an extraordinary combination of high robustness, transparency, mechanical strength and extensibility even in a wet condition. The combination of optimal phosphate and amylose concentrations in this sample probably favoured hydration......Starch directly functionalised in the plant by modulation of its biosynthesis by mutagenesis and transgene technology was exploited for its extended functionality beyond the normal variation. In this study we investigated the rheological and mechanical properties of films from such structurally...

  3. Permeability of starch gel matrices and select films to solvent vapors.

    Science.gov (United States)

    Glenn, Gregory M; Klamczynski, Artur P; Ludvik, Charles; Shey, Justin; Imam, Syed H; Chiou, Bor-Sen; McHugh, Tara; DeGrandi-Hoffman, Gloria; Orts, William; Wood, Delilah; Offeman, Rick

    2006-05-03

    Volatile agrochemicals such as 2-heptanone have potential in safely and effectively controlling important agricultural pests provided that they are properly delivered. The present study reports the permeability of starch gel matrices and various coatings, some of which are agricultural-based, that could be used in controlled release devices. Low-density, microcellular starch foam was made from wheat, Dent corn, and high amylose corn starches. The foam density ranged from 0.14 to 0.34 g/cm3, the pore volume ranged from 74 to 89%, and the loading capacity ranged from 2.3 to 7.2 times the foam weight. The compressive properties of the foam were not markedly affected by saturating the pore volume with silicone oil. The vapor transmission rate (VTR) and vapor permeability (VP) were measured in dry, porous starch foam and silicone-saturated starch gels. VTR values were highest in foam samples containing solvents with high vapor pressures. Silicone oil-saturated gels had lower VTR and VP values as compared to the dry foam. However, the silicone oil gel did not markedly reduce the VP for 2-heptanone and an additional vapor barrier or coating was needed to adequately reduce the evaporation rate. The VP of films of beeswax, paraffin, ethylene vinyl alcohol, a fruit film, and a laminate comprised of beeswax and fruit film was measured. The fruit film had a relatively high VP for polar solvents and a very low VP for nonpolar solvents. The laminate film provided a low VP for polar and nonpolar solvents. Perforating the fruit film portion of the laminate provided a method of attaining the target flux rate of 2-heptanone. The results demonstrate that the vapor flux rate of biologically active solvents can be controlled using agricultural materials.

  4. Caracterização e análise sensorial de biscoitos de polvilho elaborados com diferentes níveis de farelo de mandioca Characterization and sensory analysis of cassava starch biscuits made with different levels of cassava bagasse

    Directory of Open Access Journals (Sweden)

    Janaína Pereira de Macedo Rodrigues

    2011-12-01

    Full Text Available Objetivou-se com este trabalho avaliar as características químicas, cor, volume específico e aceitabilidade, de biscoitos elaborados com diferentes níveis de farelo de mandioca desidratado. Realizou-se previamente a desidratação do farelo de mandioca e, em seguida, elaboraram-se formulações de biscoitos com concentrações de farelo de mandioca de 0% (BP, 2% (BF2, 4% (BF4, 6% (BF6 e 8% (BF8, em substituição à fécula de mandioca. Os dados foram analisados por meio da análise de variância, teste de Tukey, em nível de 5% de significância. O teor de fibra alimentar e os atributos de cor (L*, a* e b* dos biscoitos aumentaram significativamente com a adição do farelo de mandioca desidratado, o teor de fibra alimentar total variou de 5,47g 100g-1 a 11,40g 100g-1, o de proteínas variou de 6,66g 100g-1 a 7,26g 100g-1. Em 100g de biscoito de polvilho com 8% de farelo de mandioca, encontram-se atendidas 20%, 32%, 26%, 38%, 79%, 16% e 20% da ingestão dietética de referência para o cálcio, cobre, fósforo, magnésio, manganês, potássio e zinco, respectivamente. O volume específico dos biscoitos diminuiu com o aumento de farelo de mandioca. Os biscoitos apresentaram boa aceitabilidade para aparência, sabor e textura. Conclui-se que biscoitos de polvilho elaborados com farelo de mandioca desidratado constituem um produto com bom potencial nutricional e de boa aceitabilidade.This study evaluated the chemically composition, color, specific volume and acceptability of biscuits made with cassava bagasse dehydrated. Held prior to the dehydration of cassava bagasse, then prepared themselves for producing biscuits with concentrations of cassava bagasse from 0% (BP, 2% (BF2, 4% (BF4 6% (BF6 and 8% (BF8, instead of cassava starch. Data were analyzed by analysis of variance, Tukey at 5% level of significance. The dietary fiber content and attributes of color (L*, a* b* the biscuits increased with the addition of cassava bagasse dehydrated, the

  5. PENGEMBANGAN EDIBLE FILM DENGAN MENGGUNAKAN PATI GANYONG TERMODIFIKASI IKATAN SILANG [Development of Edible Film by Using Modified Cross-Linking Ganyong Starch

    Directory of Open Access Journals (Sweden)

    Rindit Pambayun

    2011-12-01

    Full Text Available The objective of the research was to study chemical and physical characteristics of edible film of modified ganyong starch. The first step of the research was to make modified ganyong starch with cross linking method by using POCl3. The second step is to make edible film from modified ganyong starch. The results showed that the phosphate content and value of substitution degree of modified ganyong starch increased, but its amylose and starch content decreased. Edible film made of ganyong starch modified with POCl3 0.08% had the lowest water vapor transmission rate (18.25+0,003 g.m-2.day-1 and percentage elongation (17.01+0,001%, but the highest puncture strength (146.89+0.001 gf.

  6. Photoelectrocatrocatalytic hydrolysis of starch by using sprayed ZnO thin films

    Science.gov (United States)

    Sapkal, R. T.; Shinde, S. S.; Rajpure, K. Y.; Bhosale, C. H.

    2013-05-01

    Thin films of zinc oxide have been deposited onto glass/FTO substrates at optimized 400 °C by using a chemical spray pyrolysis technique. Deposited films are character photocatalytic activity by using XRD, an SEM, a UV-vis spectrophotometer, and a PEC single-cell reactor. Films are polycrystalline and have a hexagonal (wurtzite) crystal structure with c-axis (002) orientation growth perpendicular to the substrate surface. The observed direct band gap is about 3.22 eV for typical films prepared at 400 °C. The photocatalytic activity of starch with a ZnO photocatalyst has been studied by using a novel photoelectrocatalytic process.

  7. Measurement of Thermal Properties of Triticale Starch Films Using Photothermal Techniques

    Science.gov (United States)

    Correa-Pacheco, Z. N.; Cruz-Orea, A.; Jiménez-Pérez, J. L.; Solorzano-Ojeda, S. C.; Tramón-Pregnan, C. L.

    2015-06-01

    Nowadays, several commercially biodegradable materials have been developed with mechanical properties similar to those of conventional petrochemical-based polymers. These materials are made from renewable sources such as starch, cellulose, corn, and molasses, being very attractive for numerous applications in the plastics, food, and paper industries, among others. Starches from maize, rice, wheat, and potato are used in the food industry. However, other types of starches are not used due to their low protein content, such as triticale. In this study, starch films, processed using a single screw extruder with different compositions, were thermally and structurally characterized. The thermal diffusivity, thermal effusivity, and thermal conductivity of the biodegradable films were determined using photothermal techniques. The thermal diffusivity was measured using the open photoacoustic cell technique, and the thermal effusivity was obtained by the photopyroelectric technique in an inverse configuration. The results showed differences in thermal properties for the films. Also, the films microstructures were observed by scanning electron microscopy, transmission electron microscopy, and the crystalline structure determined by X-ray diffraction.

  8. Effect of stearic acid-grafted starch compatibilizer on properties of linear low density polyethylene/thermoplastic starch blown film.

    Science.gov (United States)

    Khanoonkon, Nattaporn; Yoksan, Rangrong; Ogale, Amod A

    2016-02-10

    The present work aims to investigate the effect of stearic acid-grafted starch (ST-SA) on the rheological, thermal, optical, dynamic mechanical thermal, and tensile properties of linear low density polyethylene/thermoplastic starch (LLDPE/TPS) blends, as well as on their water vapor and oxygen barrier properties. Blends consisting of LLDPE and TPS in a weight ratio of 60:40 and ST-SA at different concentrations, i.e. 1, 3 and 5%, were prepared using a twin-screw extruder. The obtained resins were subsequently converted into films via blown film extrusion. Incorporation of ST-SA resulted in a decreased degree of shear thinning, reduced ambient temperature elasticity, and improved tensile strength, secant modulus, extensibility, and UV absorption, as well as diminished water vapor and oxygen permeabilities of the LLDPE/TPS blend. These effects are attributed to the enhanced interfacial adhesion between LLDPE and TPS phases through the compatibilizing effect induced by ST-SA, and the good dispersion of the TPS phase in the LLDPE matrix. The results confirmed that ST-SA could potentially be used as a compatibilizer for the LLDPE/TPS blend system.

  9. Different strategies to improve the functionality of biodegradable films based on starch and other polymers

    OpenAIRE

    2016-01-01

    [EN] In the present Doctoral Thesis, different strategies to improve functional properties of starch films for food packaging applications were analysed: study of the effect of amylose:amylopectin ratio, blend with other polymers poly(vinyl alcohol) (PVA), and incorporation of different fillers (rice bran and cellulose nanocrystals-CNCs) and antimicrobial agents (neem oil-N, oregano essential oil-O and silver nanoparticles-AgNPs). Likewise, a biodegradation study of the films as affected by a...

  10. Establishing whether the structural feature controlling the mechanical properties of starch films is molecular or crystalline.

    Science.gov (United States)

    Li, Ming; Xie, Fengwei; Hasjim, Jovin; Witt, Torsten; Halley, Peter J; Gilbert, Robert G

    2015-03-06

    The effects of molecular and crystalline structures on the tensile mechanical properties of thermoplastic starch (TPS) films from waxy, normal, and high-amylose maize were investigated. Starch structural variations were obtained through extrusion and hydrothermal treatment (HTT). The molecular and crystalline structures were characterized using size-exclusion chromatography and X-ray diffractometry, respectively. TPS from high-amylose maize showed higher elongation at break and tensile strength than those from normal maize and waxy maize starches when processed with 40% plasticizer. Within the same amylose content, the mechanical properties were not affected by amylopectin molecular size or the crystallinity of TPS prior to HTT. This lack of correlation between the molecular size, crystallinity and mechanical properties may be due to the dominant effect of the plasticizer on the mechanical properties. Further crystallization of normal maize TPS by HTT increased the tensile strength and Young's modulus, while decreasing the elongation at break. The results suggest that the crystallinity from the remaining ungelatinized starch granules has less significant effect on the mechanical properties than that resulting from starch recrystallization, possibly due to a stronger network from leached-out amylose surrounding the remaining starch granules.

  11. Morphological characteristics and barrier properties of thermoplastic starch/chitosan blown film.

    Science.gov (United States)

    Dang, Khanh Minh; Yoksan, Rangrong

    2016-10-01

    Fabrication of starch-based edible film using blown film extrusion is challenging and interesting because this process provides continuous operation with shorter production time and lower energy consumption, is less labor intensive, and results in higher productivity than the conventional solution casting technique. Previously, we reported on the preparation and some properties of thermoplastic starch/chitosan (TPS/CTS) blown films; however, their morphological characteristics and barrier properties had not yet been elucidated. The present work thus aims to investigate the effect of chitosan (0.37-1.45%) on morphological characteristics, water vapor and oxygen barrier properties as well as hydrophilicity of the TPS and TPS/CTS films. The relationship between morphological characteristics and properties of the films was also discussed. Scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM) and X-ray photoelectron spectroscopy (XPS) confirmed the distribution and deposition of chitosan on the film surface. The existence of chitosan on the surface imparted the improved water vapor and oxygen barrier properties and the reduced surface hydrophilicity to the film. The results suggest that this biodegradable bio-based TPS/CTS film could potentially be used as an edible film for food and pharmaceutical applications.

  12. Antifungal activity by vapor contact of essential oils added to amaranth, chitosan, or starch edible films.

    Science.gov (United States)

    Avila-Sosa, Raúl; Palou, Enrique; Jiménez Munguía, María Teresa; Nevárez-Moorillón, Guadalupe Virginia; Navarro Cruz, Addí Rhode; López-Malo, Aurelio

    2012-02-01

    Antimicrobial agents can be incorporated into edible films to provide microbiological stability, since films can be used as carriers of a variety of additives to extend product shelf life and reduce the risk of microbial growth on food surfaces. Addition of antimicrobial agents to edible films offers advantages such as the use of small antimicrobial concentrations and low diffusion rates. The aim of this study was to evaluate inhibition by vapor contact of Aspergillus niger and Penicillium digitatum by selected concentrations of Mexican oregano (Lippia berlandieri Schauer), cinnamon (Cinnamomum verum) or lemongrass (Cymbopogon citratus) essential oils (EOs) added to amaranth, chitosan, or starch edible films. Essential oils were characterized by gas chromatography-mass spectrometry (GC/MS) analysis. Amaranth, chitosan and starch edible films were formulated with essential oil concentrations of 0.00, 0.25, 0.50, 0.75, 1.00, 2.00, or 4.00%. Antifungal activity was evaluated by determining the mold radial growth on agar media inoculated with A. niger and P. digitatum after exposure to vapors arising from essential oils added to amaranth, chitosan or starch films using the inverted lid technique. The modified Gompertz model adequately described mold growth curves (mean coefficient of determination 0.991 ± 0.05). Chitosan films exhibited better antifungal effectiveness (inhibition of A. niger with 0.25% of Mexican oregano and cinnamon EO; inhibition of P. digitatum with 0.50% EOs) than amaranth films (2.00 and 4.00% of cinnamon and Mexican oregano EO were needed to inhibit the studied molds, respectively). For chitosan and amaranth films a significant increase (pfilm concentrations while a significant decrease (pedible films incorporating Mexican oregano or cinnamon essential oil could improve the quality of foods by the action of the volatile compounds on surface growth of molds.

  13. Transcriptional response to petiole heat girdling in cassava

    Science.gov (United States)

    The heat-girdling technique, which is known to inhibit photoassimilate translocation, was performed on the petiole of cassava leaves at the end of the light cycle to inhibit starch remobilization during the night. The inhibition of starch remobilization caused significant starch accumulation at the ...

  14. Starch-based edible film with gum arabic for fruits coating

    Science.gov (United States)

    Razak, Aqeela Salfarina; Lazim, Azwan Mat

    2015-09-01

    Packaging waste forms a significant part of municipal solid waste and has caused increasing environmental concerns, resulting in a strengthening of various regulations aimed at reducing the amounts generated. The introduction of biodegradable materials such as edible film and coating which can be disposed directly into the soil, can be one possible solution to this problem. Edible coating is defined as a thin layer of edible material form as a film on the surface of the fruits and vegetables. This coating can affect the respiration and moisture loss. In this study, edible film and coating were used as fruit coating. The edible film were prepared with different ratios which is 2:2, 3:1, and 1:3 of starch and gum Arabic with 10% of glycerol and sorbitol as plasticiser. A study of practical application for the edible film and coating from starch with gum Arabic for fruit coating was conducted. Banana were coated with an aqueous solution of starch with gum Arabic and stored at ambient temperature (26 ± 1°C; 70 ± 10% RH). The results indicate that with the coating application, the fruits lost about 30% less weight than the uncoated fruits. The coating application was also effective in retaining the firmness of the banana and slow down the ripening process.

  15. Production of acetone-butanol-ethanol (ABE) in direct fermentation of cassava by Clostridium saccharoperbutylacetonicum N1-4.

    Science.gov (United States)

    Thang, Vu Hong; Kanda, Kohzo; Kobayashi, Genta

    2010-05-01

    In this work, acetone-butanol-ethanol (ABE) fermentation characteristics of cassava starch and cassava chips when using Clostridium saccharoperbutylacetonicum N1-4 was presented. The obtained results in batch mode using a 1-L fermenter showed that C. saccharoperbutylacetonicum N1-4 was a hyperamylolytic strain and capable of producing solvents efficiently from cassava starch and cassava chips, which was comparable to when glucose was used. Batch fermentation of cassava starch and cassava chips resulted in 21.0 and 19.4 g/L of total solvent as compared with 24.2 g/L of total solvent when using glucose. Solvent productivity in fermentation of cassava starch was from 42% to 63% higher than that obtained in fermentation using corn and sago starches in the same condition. In fermentation of cassava starch and cassava chips, maximum butanol concentration was 16.9 and 15.5 g/L, respectively. Solvent yield and butanol yield (based on potential glucose) was 0.33 and 0.41, respectively, for fermentation of cassava starch and 0.30 and 0.38, respectively for fermentation using cassava chips.

  16. Biodegradable starch-based films containing saturated fatty acids: thermal, infrared and raman spectroscopic characterization

    Directory of Open Access Journals (Sweden)

    Marcelo M. Nobrega

    Full Text Available Biodegradable films of thermoplastic starch and poly (butylene adipate co-terephthalate (PBAT containing fatty acids were characterized thermally and with infrared and Raman spectroscopies. The symmetrical character of the benzene ring in PBAT provided a means to illustrate the difference between these spectroscopic techniques, because a band appeared in the Raman spectrum but not in the infrared. The thermal analysis showed three degradation stages related to fatty acids, starch and PBAT. The incorporation of saturated fatty acids with different molecular mass (caproic, lauric and stearic did not change the nature of the chemical bonds among the components in the blends of starch, PBAT and glycerol, according to the thermal analysis, infrared and Raman spectroscopies.

  17. Effect of Acid Thinned and Acetylation Modification on the Properties of Cassava Starch%酸解和乙酰化改性对木薯淀粉性质的影响

    Institute of Scientific and Technical Information of China (English)

    李佳佳; 李航; 高群玉

    2012-01-01

    以木薯淀粉为原料,对酸解淀粉、乙酰化淀粉及酸解乙酰化淀粉的糊性质进行了研究,并用扫描电子显微镜、X射线衍射仪和傅里叶变换红外光谱仪对改性淀粉的形貌和结构进行了分析。结果表明:木薯淀粉经酸解改性改善了糊的透明度,膨胀度有所降低,糊化温度升高,峰值黏度显著降低,凝沉性有所改善;乙酰化改性增加了淀粉糊的透明度,膨胀度提高,降低了糊化温度,峰值黏度增加,糊的抗凝沉性增强但热糊稳定性差;酸解乙酰化复合改性显著提高了淀粉糊的透明度,降低淀粉的膨胀度及糊化温度,峰值黏度显著降低,抗凝沉性明显增强,冷、热糊稳定性提高。扫描电镜、X衍射数据及红外图谱表明,3种变性处理均没有改变木薯淀粉的晶型和基本结构,颗粒形貌也没有发生显著变化。%In order to study the influence of acid thinned and acetylation modification on the properties of cassava starch, the paste properties of acid thinned and acetylated cassava starch were investigated; the morphological and structural changes of the modified starches were observed and analyzed by means of SEM,XRD and FT-IR. The results showed that : after acid thinned modification , the transparency of the paste increased obviously, swelling power and peak viscosity was decreased, the gelatinized temperature was increased, and the retrogradation was improved;the acetylated starch gelatinization temperature was decreased, paste transparency was better ,retrogradation and swelling power increased, the peak viscosity was increased but hot paste stability was poor. The modification by acid thinned and aeetylation decreased the gelatinization temperature and swelling power of cassava starch, improved the paste transparency and retrogradation obviously, enhanced the cold and hot paste stability, and the peak viscosity was de- creased. The crystalline pattern were

  18. Effect of replacement of corn starch by whey protein isolate in biodegradable film blends obtained by extrusion.

    Science.gov (United States)

    Azevedo, Viviane Machado; Borges, Soraia Vilela; Marconcini, José Manoel; Yoshida, Maria Irene; Neto, Alfredo Rodrigues Sena; Pereira, Tamara Coelho; Pereira, Camila Ferreira Gonçalves

    2017-02-10

    The aim of this study was to evaluate the effect of replacing corn starch by whey protein isolated (WPI) in biodegradable polymer blends developed by extrusion. X-ray diffraction showed the presence of a Vh-type crystalline arrangement. The films were homogeneous, indicating strong interfacial adhesion between the protein and the thermoplastic starch matrix (TPS) as observed in scanning electron microscopy. The addition of WPI on TPS matrix promoted an increase in the thermal stability of the materials. It was observed 58.5% decrease in the water vapor permeability. The effect of corn starch substitution by WPI on mechanical properties resulted in a more resistant and less flexible film when compared the TPS film. The addition of WPI caused greenish yellow color and less transparent films. The substitution of corn starch by WPI made it possible to obtain polymer blends with improved properties and represents an innovation for application as a packaging material.

  19. Fécula de mandioca e farinha de aveia como substitutos de gordura na formulação de hambúrguer de carne ovina Cassava starch and oatmeal as fat replacers of lamb burgers

    Directory of Open Access Journals (Sweden)

    Larissa Mont'Alverne Jucá Seabra

    2002-12-01

    Full Text Available Nos produtos cárneos com teor de gordura reduzido, ingredientes têm sido utilizados para manter os atributos de qualidade e rendimento. As farinhas de mandioca e de aveia têm sido usadas como componentes úteis para melhorar as características de suculência e maciez em hambúrgueres com baixo nível de gordura. O objetivo do presente estudo foi verificar o efeito da fécula de mandioca e da farinha de aveia sobre as características físicas, químicas e sensoriais de hambúrgueres de carne ovina com teor de gordura reduzido. Foram testadas 4 formulações à base de carne ovina limpa: testemunha sem gordura adicionada (F1, com 9,15% de gordura ovina adicionada (F2, sem gordura adicionada e 2% de fécula de mandioca (F3 e sem gordura adicionada e 2% de farinha de aveia (F4. Foram avaliados durante o cozimento: composição centesimal, rendimento, encolhimento e capacidade de retenção de água, força de cisalhamento, cor e análise sensorial dos hambúrgueres. Os produtos nos quais foram adicionados os substitutos de gordura (F3 e F4 apresentaram menor teor de gordura, antes e depois de cozidos, menor encolhimento, maior rendimento e capacidade de retenção de água do que os das formulações F1 e F2. A força de cisalhamento e a intensidade de vermelho (a* foram menores nos produtos aos quais foram adicionados os substitutos de gordura (F3 e F4 do que nos produtos sem substituição (F1 e F2. Não foram detectadas diferenças na aceitação global dos produtos com diferentes formulações. Desta forma, conclui-se que o uso de fécula de mandioca e farinha de aveia pode ser uma alternativa de substituição de gordura em produtos de carne ovina de baixo nível de gordura tipo hambúrguer.Several ingredients have been successfully tested as fat replacers in meat products maintaining desirable attributes like tenderness, juiciness and cooking yield. Cassava starch and oatmeal have been used to maintain good texture, juiciness and overall

  20. Synthesis of nano cellulose fibers and effect on thermoplastics starch based films.

    Science.gov (United States)

    Savadekar, N R; Mhaske, S T

    2012-06-01

    Starch based films limit their application due to highly hydrophilic nature and poor mechanical properties. This problem was sought to be overcome by forming a nanocomposite of Thermoplastic starch (TPS) and Nano-Cellulose fibers (NCF). NCF was successfully synthesised from short stable cotton fibres by a chemo-mechanical process. TPS/NCF composite films were prepared by solution casting method, and their characterizations were done in terms of differential scanning calorimeter (DSC), morphology (SEM), water vapor permeability (WVTR), oxygen transmission rate (OTR), X-ray diffractograms, light transmittance and tensile properties. At very low concentration of NCF filled TPS composite film showed improvement in properties. The 0.4 t% NCF loaded TPS films showed 46.10% improved tensile strength than by base polymer film, beyond that 0.5 t% concentration tensile strength starts to deteriorate. WVTR and OTR results showed improved water vapor barrier property of TPS matrix. The DSC thermograms of TPS and composite films did not show any significant effect on the melting point of composite film to the base polymer TPS.

  1. Identification of the bacterial community responsible for traditional fermentation during sour cassava starch, cachaça and minas cheese production using culture-independent 16s rRNA gene sequence analysis

    Science.gov (United States)

    Lacerda, Inayara C. A.; Gomes, Fátima C. O.; Borelli, Beatriz M.; Faria Jr., César L. L.; Franco, Gloria R.; Mourão, Marina M.; Morais, Paula B.; Rosa, Carlos A.

    2011-01-01

    We used a cultivation-independent, clone library-based 16S rRNA gene sequence analysis to identify bacterial communities present during traditional fermentation in sour cassava starch, cachaça and cheese production in Brazil. Partial 16S rRNA gene clone sequences from sour cassava starch samples collected on day five of the fermentation process indicated that Leuconostoc citreum was the most prevalent species, representing 47.6% of the clones. After 27 days of fermentation, clones (GenBank accession numbers GQ999786 and GQ999788) related to unculturable bacteria were the most prevalent, representing 43.8% of the clones from the bacterial community analyzed. The clone represented by the sequence GQ999786 was the most prevalent at the end of the fermentation period. The majority of clones obtained from cachaça samples during the fermentation of sugar cane juice were from the genus Lactobacillus. Lactobacillus nagelli was the most prevalent at the beginning of the fermentation process, representing 76.9% of the clones analyzed. After 21 days, Lactobacillus harbinensis was the most prevalent species, representing 75% of the total clones. At the end of the fermentation period, Lactobacillus buchneri was the most prevalent species, representing 57.9% of the total clones. In the Minas cheese samples, Lactococcus lactis was the most prevalent species after seven days of ripening. After 60 days of ripening, Streptococcus salivarius was the most prevalent species. Our data show that these three fermentation processes are conducted by a succession of bacterial species, of which lactic acid bacteria are the most prevalent. PMID:24031676

  2. Thermoplastic starch plasticized with alginate-glycerol mixtures: Melt-processing evaluation and film properties.

    Science.gov (United States)

    López, Olivia V; Ninago, Mario D; Lencina, M M Soledad; García, María A; Andreucetti, Noemí A; Ciolino, Andrés E; Villar, Marcelo A

    2015-08-01

    Corn starch melt-processing in the presence of a commonly used plasticizer mixture (water/glycerol) and a non-conventional alternative (alginate/glycerol) was evaluated. All assayed formulations were successfully processed by melt-mixing and injected in circular probes. It was determined that all samples presented a typical viscoelastic behavior, observing a decrease in storage and loss modulus with water and alginate concentration, which facilitated samples processability. Concerning to thermal stability, it was not affected neither for water nor alginate presence. From injected probes, flexible films were obtained by thermo-compression. Films with the highest assayed water content presented a sticky appearance, whereas those containing alginate were non-tacky. Plasticizing action of water and alginate was evidenced by the occurrence of homogeneous fracture surfaces, without the presence of unmelted starch granules. Besides, the shift of glass transition temperature to lower values also corroborated the plasticizing effect of both additives. In conclusion, obtained results demonstrated the well-plasticizing action of sodium alginate on starch matrix, turning this additive into a promissory alternative to replace water during melt-processing of thermoplastic corn-starch.

  3. Production of methane by co-digestion of cassava pulp with various concentrations of pig manure

    DEFF Research Database (Denmark)

    Panichnumsin, Pan; Nopharatana, Annop; Ahring, Birgitte Kiær

    2010-01-01

    Cassava pulp is a major by-product produced in a cassava starch factory, containing 50-60% of starch (dry basis). Therefore, in this study we are considering its potential as a raw material substrate for the production of methane. To ensure sufficient amounts of nutrients for the anaerobic digest...

  4. Sensory evaluation of aromatic foods packed in developed starch based films using fuzzy logic

    Directory of Open Access Journals (Sweden)

    Tanima Chowdhury

    2015-04-01

    Full Text Available The last two decades have seen attempts to replace non biodegradable, synthetic food packaging films with alternatives made from biopolymers. The objective of the present work was to evaluate sensory quality of tea leaf and culinary tastemaker powder when sealed in pouches based on starch films.Films were developed from corn starch and a functional polysaccharide (FP from amylose (AM, methylcellulose (MC, and hydroxypropylmethylcellulose (HPMC, using a casting technique. Pouches were stored inside a secondary package (plastic jar under ambient condition for 90 days. Sensory attributes of the stored food samples were evaluated (tea in liquor form and the scores analysed by fuzzy logic. Results were compared with similarly stored foods but using market available poly-pouches as packaging material.For tea and tastemaker in general, the relative importance of the sensory attributes under consideration was assessed as:  aroma (Highly important >taste (Highly important>colour (Highly important > strength (Important for tea, and taste (Highly important>aroma (Highly important>colour (Important>appearance (Important for tastemaker. Among the three films that were developed, the highly important sensory attributes of aroma and taste were maintained as ‘Very good’ when the foods were packed in starch–HPMC/AM film. When the products were packed in market-available poly-pouches they exhibited similar attributes. With the exception of ‘Very good’ maintenance of the colour of tastemaker by the commercial pouch, irrespective of film and food, the colour and strength/appearance were retained in the ‘Good’-‘Satisfactory’ range. The overall sensory score of tea was also maintained as ‘Very good’ in starch-HPMC film.

  5. Comparison of three cyanogen assays for total cyanogens in cassava (Manihot esculenta Crantz)

    DEFF Research Database (Denmark)

    Saka, J.D.K.; Mhone, A.R.K.; Brimer, Leon

    1997-01-01

    The sensitivity and reproducibility of three methods for determining the total cyanogenic potential (CNp) of 7 fresh and processed cassava varieties were determined and compared. The total cyanogen content of fresh cassava roots and three cassava products (kondowole, makaka, and starch) were...... analysed by the acid hydrolysis, microdiffusion with solid state detection and Cooke's enzymatic assays. The total cyanogen contents of the cassava, obtained by the three methods were not significantly different (p

  6. Fracture mechanisms in biopolymer films using coupling of mechanical analysis and high speed visualization technique

    NARCIS (Netherlands)

    Paes, S.S.; Yakimets, I.; Wellner, N.; Hill, S.E.; Wilson, R.H.; Mitchell, J.R.

    2010-01-01

    The aim of this study was to provide a detailed description of the fracture mechanisms in three different biopolymer thin materials: gelatin, hydroxypropyl cellulose (HPC) and cassava starch films. That was achieved by using a combination of fracture mechanics methodology and in situ visualization w

  7. Effect of organic acids as additives on the performance of thermoplastic starch/polyester blown films.

    Science.gov (United States)

    Olivato, J B; Grossmann, M V E; Bilck, A P; Yamashita, F

    2012-09-01

    The influence of citric acid (CA), malic acid (MA) and tartaric acid (TA) in starch/poly (butylene adipate co-terephthalate) blown films was evaluated by examining the barrier, structural and mechanical properties of the films. These properties were analysed in different relative humidities. Greater concentrations of TA and CA (1.5 wt%) produced films with improved tensile strength (6.8±0.3 and 6.7±0.3 MPa, respectively), reduced water vapour permeability and a more homogeneous structure. The compatibilising effect of MA was less efficient, as shown in the scanning electron microscopy (SEM) images. Changes in the relative humidity (RH) affected the elongation of the films, which reached values of 5.7±0.5 at 33% RH and increased to 312.4±89.5% at 53% RH. The FT-IR spectra showed no additional reactions caused by the incorporation of the additives, and the observed results are attributed to the esterification reactions and/or hydrolysis of the starch, producing films with interesting properties. This process represents an alternative to the use of non-biodegradable materials.

  8. Photoelectrocatrocatalytic hydrolysis of starch by using sprayed ZnO thin films

    Institute of Scientific and Technical Information of China (English)

    R.T.Sapkal; S.S.Shinde; K.Y.Rajpure; C.H.Bhosale

    2013-01-01

    Thin films of zinc oxide have been deposited onto glass/FTO substrates at optimized 400 ℃ by using a chemical spray pyrolysis technique.Deposited films are characterized for their structural,morphological optical and photocatalytic activity by using XRD,an SEM,a UV-vis spectrophotometer,and a PEC single-cell reactor.Films are polycrystalline and have a hexagonal (wurtzite) crystal structure with c-axis (002) orientation growth perpendicular to the substrate surface.The observed direct band gap is about 3.22 eV for typical films prepared at 400 ℃.The photocatalytic activity of starch with a ZnO photocatalyst has been studied by using a novel photoelectrocatalytic process.

  9. Citric acid as multifunctional agent in blowing films of starch/PBAT

    Directory of Open Access Journals (Sweden)

    Patrícia Salomão Garcia

    2011-09-01

    Full Text Available Citric acid was used as a compatibilizer in the production of starch and PBAT films plasticized with glycerol and processed by blow extrusion. Films produced were characterized by WVP, mechanical properties, FT-IR-ATR and SEM. WPV ranged from 3.71 to 12.73×10-11 g m-1 s-1 Pa-1, while tensile strength and elongation at break ranged from 1.81 to 7.15 MPa and from 8.61 to 23.63%, respectively. Increasing the citric acid concentration improved WVP and slightly decreased film resistance and elongation. The films micrographs revealed a more homogeneous material with the addition of citric acid. However, the infrared spectra revealed little about cross-linking esterification reaction

  10. 絮凝法提取木薯黄浆废水中植物蛋白质的效果研究%The study of flocculation extracted starch of cassava yellow pulp wastewater

    Institute of Scientific and Technical Information of China (English)

    万思杰; 李小丽; 彭小玉

    2016-01-01

    文章采用混凝技术提取木薯黄浆废水中的植物蛋白质物质,实验通过选取最佳的混凝剂和助凝剂种类及其最佳用量,并研究 pH、沉淀时间对混凝效果的影响,为木薯黄浆废水的资源化利用提供科学依据。单因素实验结果表明:分别以1%的PAC、1%的氯化铁和1%的改性玉米淀粉处理木薯黄浆废水,三种絮凝剂的最佳投加量分别为0.133g/L、0.133g/L和0.05g/L,最佳絮凝pH分别为9、2和8,三种絮凝剂的沉淀时间均大于15min时处理效果较佳,此时木薯黄浆淀粉废水的浊度去除率均到达80%以上,COD去除率达到50%。复配实验结果表明:PAC与PAM的复配投加后,PAC投加量为0.02g/L,PAM投加量为0.002g/L,浊度去除率从80%左右上升至98.2%,COD去除率上升至51.8%,复配絮凝剂相比单一絮凝剂提取植物蛋白效果更好。%The purpose of this study is trying to use technology for cassava starch production coagulation pretreatment of wastewater, which includes selecting the best coagulant type, determine coagulant, the optimum coagulant dosage, pH studies on mixed coagulation effect for the comprehensive management of cassava starch wastewater to provide some design parameters. Experimental results that the single factor, 0.1%PAC and 1%ferric chloride dosage 0.133g/L, 1%modified corn starch dosage0.05g/L, ferric chloride optimum pH was 2, PAC and corn starch optimal pH were 9 and 8, the settling time process is effective when more than 15min. Through traditional flocculants in yellow cassava pulp wastewater to determine the cationic polyacrylamide (PAM) and aluminum chloride (PAC) compound used better. PAM and the PAM complex volume ratio is 10:1. PAC dosage can be reduced twice, turbidity removal efficiency rise to 98.2% from 80%, showing that not only enhances the compound flocculant flocculation effect, but also reduces the pharmaceutical dosage.

  11. Cassava Genetic Transformation and its Application in Breeding

    Institute of Scientific and Technical Information of China (English)

    Jia Liu; Qijie Zheng; Qiuxiang Ma; Kranthi Kumar Gadidasu; Peng Zhang

    2011-01-01

    As a major source of food, cassava (Manihot esculenta Crantz) is an important root crop in the tropics and subtropics of Africa and Latin America, and serves as raw material for the production of starches and bioethanol in tropical Asia. Cassava improvement through genetic engineering not only overcomes the high heterozygosity and serious trait separation that occurs in its traditional breeding, but also quickly achieves improved target traits. Since the first report on genetic transformation in cassava in 1996, the technology has gradually matured over almost 15 years of development and has overcome cassava genotype constraints, changing from mode cultivars to farmer-preferred ones.Significant progress has been made in terms of an increased resistance to pests and diseases, biofortification, and improved starch quality,building on the fundamental knowledge and technologies related to planting, nutrition, and the processing of this important food crop that has often been neglected. Therefore, cassava has great potential in food security and bioenergy development worldwide.

  12. Effect of EMA and antioxidants on properties of thermoplastic starch blown films

    Science.gov (United States)

    Threepopnatkul, P.; Kulsetthanchalee, C.; Sittattrakul, A.; Kaewjinda, E.

    2015-07-01

    The objectives of this study were to investigate the effect of poly(ethylene-co-methyl acrylate) (EMA) at 10, 30 and 50 wt% on the morphological properties, moisture sorption, water vapor permeability and biodegradability of thermoplastic starch (TPS). Urea and formamide were used as a mixed plasticizer. In addition, the effect of antioxidants namely, 3,5-di-tert-butyl-4-hydroxyhydrocinnamate (DTBH), butylated hydroxytoluene (BHT) and bis(octadecyl)hydroxylamine (BOH) at 1 wt% on the properties of TPS/EMA film was investigated. TPS/EMA films were produced by a blown film molding machine and characterized by scanning electron microscropy, moisture sorption, water vapor permeability and biodegradability measurement. Results found that the increment of EMA content in the TPS matrix could improve the water sorption, water vapor permeability and biodegradability properties of TPS/EMA films. For biodegradation, the weight loss of the blended films was directly proportional to TPS content. Regarding the antioxidants effect, the water vapor permeability of TPS/EMA films containing DTBH was higher than the one with BOH and BHT. However, the antioxidants contributed little to the biodegradability of TPS/EMA films and had no effect on the moisture sorption of TPS/EMA films.

  13. Effect of plasticizers on properties of pregelatinised starch acetate (Amprac 01) free films.

    Science.gov (United States)

    Bonacucina, Giulia; Di Martino, Piera; Piombetti, Martina; Colombo, Angela; Roversi, Francesco; Palmieri, Giovanni F

    2006-04-26

    Film coating is a technique widely used in the pharmaceutical field to improve and modify technological and release characteristics of capsules, tablets and granules. In this paper physical and mechanical properties of free films of Amprac 01, obtained by the solvent cast method, were studied in order to investigate the film forming ability of this modified starch and the effects of the addition of different plasticizers. A morphological microscopical analysis (SEM) was performed to study surface properties of the films, while thermal analysis (DSC) was carried out to investigate the influence of different types of plasticizers on the glass transition temperature of the polymer. Then a mechanical characterization permitted to evaluate important parameters such as film crack resistance and deformation at break. Extensional creep/relaxation tests were also performed to investigate the viscoelastic characteristics. As clearly demonstrated by the T(g) values, the residual water present in the films acted as plasticizers, making possible the formation of free films characterised by good macroscopical and mechanical properties. Except glycerol, the kind and amount of the other tested plasticizers did not markedly improve the mechanical and crack resistance of the films.

  14. WATER SORPTION PROPERTIES AND ANTIMICROBIAL ACTION OF ZINC OXIDE NANO PARTICLES LOADED SAGO STARCH FILM

    Directory of Open Access Journals (Sweden)

    Sunil Bajpai

    2013-02-01

    Full Text Available In this work, sago starch based films have been loaded with ZnO nanoparticles prepared insitu via using an unique equilibration-cum-hydrothermal approach. The films have been characterized by XRD, DSC,SPR ,FTIR and SEM analysis. The moisture absorption behavior of plain and ZnO nanoparticles loaded films have been studied at 23, 31 and 37o C.The equilibrium moisture uptake data was found to fit well on GAB isotherm model and the monolayer sorption capacity Mo for the plain and ZnO nanoparticles loaded films was 0.089, 0.039 ,0.021 g/g and 0.042, 0.012, 0.007 g/g at 23,31 and 37 oC respectively. Moreover, the water vapor transmission rates (WVTR for plain and ZnO nanoparticles loaded films at 23,31,37 oC were 11.19x10-4, 48.9x10-4, 62.1x10-4 and 3.73 x10-4, 6.21x10-4, 24.8x10-4 respectively. These films have shown excellent antibacterial action against model bacteria E.coli when investigated qualitatively by zone inhibition method. Films exhibit great potential to be used as packaging films to protect food stuff against microbial contaminents.

  15. Effect of incorporation of nutraceutical capsule waste of safflower oil in the mechanical characteristics of corn starch films

    Directory of Open Access Journals (Sweden)

    Camila de CAMPO

    2016-01-01

    Full Text Available Abstract Biodegradable films blends made of safflower oil nutraceutical capsules waste corn starch (20:4, 30:4, 40:4 and 50:4 were prepared. The objective of this study was to evaluate the influence of addition of different concentrations of safflower oil nutraceutical capsule waste in the mechanical properties (tensile strength, elongation at break, Young’s modulus and thickness of corn starch films. A decrease in tensile strength and Young’s modulus and an increase in elongation at break were observed with the increase in the content of the nutraceutical capsule waste. The results showed that the blends of safflower oil capsules waste-corn starch films demonstrated promising characteristics to form biodegradable films with different mechanical characteristics.

  16. Starch-based Antimicrobial Films Incorporated with Lauric Acid and Chitosan

    Science.gov (United States)

    Salleh, E.; Muhamad, I. I.

    2010-03-01

    Antimicrobial (AM) packaging is one of the most promising active packaging systems. Starch-based film is considered an economical material for antimicrobial packaging. This study aimed at the development of food packaging based on wheat starch incorporated with lauric acid and chitosan as antimicrobial agents. The purpose is to restrain or inhibit the growth of spoilage and/or pathogenic microorganisms that are contaminating foods. The antimicrobial effect was tested on B. substilis and E. coli. Inhibition of bacterial growth was examined using two methods, i.e. zone of inhibition test on solid media and liquid culture test (optical density measurements). The control and AM films (incorporated with chitosan and lauric acid) were produced by casting method. From the observations, AM films exhibited inhibitory zones. Interestingly, a wide clear zone on solid media was observed for B. substilis growth inhibition whereas inhibition for E. coli was not as effective as B. substilis. From the liquid culture test, the AM films clearly demonstrated a better inhibition against B. substilis than E. coli.

  17. Structure and physical properties of starch/poly vinyl alcohol/laponite RD nanocomposite films.

    Science.gov (United States)

    Tang, Xiaozhi; Alavi, Sajid

    2012-02-29

    Nanocomposites of starch, poly vinyl alcohol (PVOH), and laponite RD (LRD) were produced by solution mixing and cast into films. In general, an increase in LRD content (0-20%) enhanced tensile strength and decreased water vapor permeability, irrespective of the relative humidity (50% and 75% RH). Tensile strength (TS) of starch/PVOH/LRD films ranged from 6.51 to 13.3 MPa. At 75% RH, TS was up to 65% higher as compared to films with sodium montmorillonite as filler. The most striking results were obtained with respect to elongation at break (E%), which ranged from 144% to 312%. Contrary to other polymer/clay nanocomposites, E% increased on addition of 5-20% LRD and was up to 175% higher than the control without clay. Nanocomposite structure and interactions were investigated using X-ray diffraction, transmission electron microscopy, and differential scanning calorimetry. Results indicated that LRD was a compatibilizer and cross-linking agent between polymers, and has the potential for use in biodegradable packaging films with good mechanical performance even in high humidity conditions.

  18. Filmes de amidos de mandioca modificados para recobrimento e conservação de uvas

    Directory of Open Access Journals (Sweden)

    Suellen Laís Vicentino

    2011-01-01

    Full Text Available In this article, films were produced with six types of cassava's starch mixed with gelatin and plasticized with sorbitol. These films were used in covering of grapes 'Benitaka' (Vitis vinifera L. as biodegradable packaging. The acetylated starch film showed the best results in solubility, thickness and homogeneity, besides the less water loss the fruit, resulting in better coverage, increasing the shelf life fruits in 12 days. These results demonstrate the great potential of using films in food conservation, adding value to agricultural activity and helping to reduce non-biodegradable plastics in the environment.

  19. Effect of thermal and chemical modifications on the mechanical and release properties of paracetamol tablet formulations containing corn, cassava and sweet potato starches as filler-binders

    Directory of Open Access Journals (Sweden)

    Mariam Vbamiunomhene Lawal

    2015-07-01

    Conclusions: Modification of the experimental starches improved the mechanical and release properties of directly compressed paracetamol tablet formulations. Thus, they can be developed for use as pharmaceutical excipients in specific formulations.

  20. Cassava biology and physiology.

    Science.gov (United States)

    El-Sharkawy, Mabrouk A

    2004-11-01

    Cassava or manioc (Manihot esculenta Crantz), a perennial shrub of the New World, currently is the sixth world food crop for more than 500 million people in tropical and sub-tropical Africa, Asia and Latin America. It is cultivated mainly by resource-limited small farmers for its starchy roots, which are used as human food either fresh when low in cyanogens or in many processed forms and products, mostly starch, flour, and for animal feed. Because of its inherent tolerance to stressful environments, where other food crops would fail, it is often considered a food-security source against famine, requiring minimal care. Under optimal environmental conditions, it compares favorably in production of energy with most other major staple food crops due to its high yield potential. Recent research at the Centro Internacional de Agricultura Tropical (CIAT) in Colombia has demonstrated the ability of cassava to assimilate carbon at very high rates under high levels of humidity, temperature and solar radiation,which correlates with productivity across all environments whether dry or humid. When grown on very poor soils under prolonged drought for more than 6 months, the crop reduce both its leaf canopy and transpiration water loss, but its attached leaves remain photosynthetically active, though at greatly reduced rates. The main physiological mechanism underlying such a remarkable tolerance to drought was rapid stomatal closure under both atmospheric and edaphic water stress, protecting the leaf against dehydration while the plant depletes available soil water slowly during long dry periods. This drought tolerance mechanism leads to high crop water use efficiency values. Although the cassava fine root system is sparse, compared to other crops, it can penetrate below 2 m soil,thus enabling the crop to exploit deep water if available. Leaves of cassava and wild Manihot possess elevated activities of the C4 enzyme PEP carboxylase but lack the leaf Kranz anatomy typical of C4

  1. Changes in physical properties of extruded sour cassava starch and quinoa flour blend snacks Mudanças nas propriedades físicas de snacks extrusados de misturas de polvilho azedo e farinha de quinoa

    Directory of Open Access Journals (Sweden)

    Lívia Giolo Taverna

    2012-12-01

    Full Text Available Given the broad acceptance of sour cassava starch biscuits in Brazil and the nutritional quality of quinoa flour, this study aimed to evaluate the effect of extrusion temperature, screw speed, moisture, and amount of quinoa flour on the physical properties of puffed snacks. Extrusion process was carried out using a single-screw extruder in a factorial central composite design with four factors. Effects of moisture and amount of quinoa flour on the expansion index and specific volume of snacks were observed. There was a pronounced increase in water solubility index of blends with the extrusion process with significant effects of all process parameters on the WSI. Higher water absorption index (WAI was observed under high temperature, low moisture, and lower quinoa flour amount. Temperature and amount of quinoa flour influenced the color of the snacks. A positive quadratic effect of quinoa flour on hardness of products was observed. Blends of sour cassava starch and quinoa flour have good potential for use as raw material in production of extruded snacks with good physical properties.Dada a ampla aceitação do biscoito de polvilho azedo no Brasil e a qualidade nutricional da farinha de quinoa, este trabalho objetivou avaliar o efeito da temperatura de extrusão, rotação da rosca, umidade e porcentagem de farinha de quinoa sobre as propriedades físicas de snacks expandidos. O processo foi realizado em extrusor monorrosca, seguindo o delineamento central composto rotacional para quatro fatores. Foi observado o efeito da umidade e da porcentagem de farinha de quinoa sobre o índice de expansão e volume específico. Houve um aumento pronunciado na solubilidade das misturas com o processo de extrusão, com efeitos significativos de todos os parâmetros de processo no ISA. Maior índice de absorção de água (IAA foi observado em alta temperatura, baixa umidade e menor porcentagem de farinha de quinoa. Temperatura e porcentagem de farinha de

  2. Water resistance and thermal properties of polyvinyl alcohol-starch fiber blend film

    Science.gov (United States)

    Salleh, M. S. N.; Nor, N. N. Mohamed; Mohd, N.; Draman, S. F. Syed

    2017-02-01

    The growing attention of starch fiber (SF) has led to the innovation of Polyvinyl Alcohol-SF (PVA-SF) blends. This blend is regarded as the biodegradable material which aims to reduce the accumulation of synthetic polymer solid waste derived from petroleum. In this study, the thermal blending characterizations of PVA-SF were investigated by differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The water resistance of the blend was also evaluated to study the polarity of the blends. The blend was prepared by plasticizing the polyvinyl alcohol with glycerol and distilled water with the addition of starch fiber. The incorporation of SF to the blends was at 10 wt% to 50 wt% composition. Based on the thermal analysis, PVA-SF blends were suitable for processing at high temperatures, which can be seen by the shifted onset degradation temperature to a higher temperature. This is because cyclic hemiacetals which were provided by SF can act to prevent the thermal attacks. Conversely, increasing the starch fiber proportion to the film blend reduce the endothermic peak amplitude in the DSC thermogram. It was found that PVA-SF blend at the higher composition of SF had the highest water resistance. This may be attributed to the content of fibre in SF which is hydrophilic.

  3. Mechanical properties and total hydroxycinnamic derivative release of starch/glycerol/Melissa officinalis extract films

    Directory of Open Access Journals (Sweden)

    Letícia Mello Rechia

    2010-09-01

    Full Text Available The aim of this study was to investigate the mechanical properties of starch/glycerol/Melissa officinalis, a topical drug delivery system for labial herpes treatment. Four films were prepared with different concentrations of starch, glycerol, and Melissa officinalis extract. The results revealed that increasing the glycerol concentration in the film reduced elasticity modulus and tensile strength, exhibiting a plasticizing effect. The increase in free volume resulted in increased release of hydroxycinnamic derivatives expressed as rosmarinic acid.O objetivo deste trabalho foi estudar as propriedades mecânicas e o mecanismo de liberação de um sistema tópico de liberação prolongada para o tratamento do Herpes labial a partir de filmes de amido/glicerol/extrato de Melissa officinalis, planta com comprovada atividade antiviral. Foram obtidos quatro filmes poliméricos com diferentes concentrações de amido, glicerol e extrato de Melissa officinalis os quais foram caracterizados mecanicamente e determinado o perfil de liberação de derivados hidroxicinâmicos. Os resultados demonstraram que o aumento da concentração de glicerol no filme produz uma redução no módulo de elasticidade e na tensão de deformação como conseqüência do efeito plastificante. O aumento no volume livre do polímero resultou em aumento da liberação dos derivados hidroxicinâmicos expressos como ácido rosmarínico.

  4. Transcriptional response to petiole heat girdling in cassava.

    Science.gov (United States)

    Zhang, Yang; Ding, Zehong; Ma, Fangfang; Chauhan, Raj Deepika; Allen, Doug K; Brutnell, Thomas P; Wang, Wenquan; Peng, Ming; Li, Pinghua

    2015-01-01

    To examine the interactions of starch and sugar metabolism on photosynthesis in cassava, a heat-girdling treatment was applied to petioles of cassava leaves at the end of the light cycle to inhibit starch remobilization during the night. The inhibition of starch remobilization caused significant starch accumulation at the beginning of the light cycle, inhibited photosynthesis, and affected intracellular sugar levels. RNA-seq analysis of heat-treated and control plants revealed significantly decreased expression of genes related to photosynthesis, as well as N-metabolism and chlorophyll biosynthesis. However, expression of genes encoding TCA cycle enzymes and mitochondria electron transport components, and flavonoid biosynthetic pathway enzymes were induced. These studies reveal a dynamic transcriptional response to perturbation of sink demand in a single leaf, and provide useful information for understanding the regulations of cassava under sink or source limitation.

  5. Influence of the use of acids and films in post-harvest lychee conservation

    Directory of Open Access Journals (Sweden)

    Danielle Fabíola Pereira da Silva

    2012-12-01

    Full Text Available Lychee (Litchi chinensis Sonn. has a high commercial value; however, it has a short shelf-life because of its rapid pericarp browning. The objective of this study was to evaluate the shelf-life of 'Bengal' lychee fruits stored after treatment with hydrochloric acid and citric acid, associated with cassava starch and plastic packaging. Uniformly red pericarp fruits were submitted to treatments: 1-(immersion in citric acid 100 mM for 5 minutes + cassava starch 30 g L-1 for 5 minutes, 2-(immersion in hydrochloric acid 1 M for 2 minutes + starch cassava 30 g L-1 for 5 minutes, 3-(immersion in citric acid 100 mM for 5 minutes + polyvinyl chloride film (PVC, 14 µm thick and 4-(immersion in hydrochloric acid 1 M for 2 minutes + PVC film. During 20 days, the fruits were evaluated for mass loss, pericarp color, pH, soluble solids and titratable acidity, vitamin C of the pulp and pericarp and activities of polyphenol oxidase and peroxidase of the pericarp. The treatment with hydrochloric acid associated with PVC was the most effective in maintaining the red color of the pericarp for a period of 20 days and best preservation of the fruit. The cassava starch associated with citric acid, and hydrochloric acid did not reduce the mass loss and did not prevent the browning of lychee fruit pericarp.

  6. Effects of sodium chloride and sodium sulfate on the cross-linking reaction of cassava starch%氯化钠及硫酸钠对木薯淀粉交联反应的影响

    Institute of Scientific and Technical Information of China (English)

    熊小雅; 叶为标; 高群玉

    2016-01-01

    The experiment was designed to determine the relationships between osmotic pressure and degree of substitution,and the viscosity characteristics of the starch samples. Brabender viscometer was used for the determination of cross–linked cassava starch that dealed with osmotic pressure. When sodium chloride was used as osmotic pressure enhancer in cross–linking reaction,with the increase of osmotic pressure,the initial gelatinization temperature increased,and the peak viscosity and the final viscosity decreased. As the osmotic pressure reached high,the retrogradation value and the breakdown value both tended to zero. When sodium sulfate was used instead of sodium chloride,as the osmotic pressure increased,the initial gelatinization temperature didn’t change significantly,the peak viscosity leveled off following decrease,the final viscosity increased(not significant)after decrease,the breakdown value was in contrast with the final viscosity,and the retrogradation decreased. The degree of crosslinking increased with the increase of osmotic pressure that produced by sodium chloride or sodium sulfate. In addition,we utilized polarizing microscope and FTIR to analyze the cross–linked cassava starch that dealed with osmotic pressure,and measured their transparency,shear resistance and retrogradation resistance,the results showed that the corresponding properties of the cross–linked starch changed.%旨在确定渗透压与交联取代度和所得淀粉糊黏度间的关系。应用Brabender连续黏度计对渗透压处理交联木薯淀粉进行了测定。当氯化钠作为交联反应渗透压促进剂时,随渗透压增大,所得淀粉样品的起始糊化温度增加,峰值黏度和最终黏度减小;高渗透压时,凝沉值和崩解值都趋于0。而硫酸钠作渗透压促进剂时,随渗透压的增大,起始糊化温度变化不明显,峰值黏度先下降后缓慢下降,最终黏度先减后增(增加不显著),崩解值先增

  7. Intelligent pH indicator film composed of agar/potato starch and anthocyanin extracts from purple sweet potato.

    Science.gov (United States)

    Choi, Inyoung; Lee, Jun Young; Lacroix, Monique; Han, Jaejoon

    2017-03-01

    A new colorimetric pH indicator film was developed using agar, potato starch, and natural dyes extracted from purple sweet potato, Ipomoea batatas. Both agar and potato starch are solid matrices used to immobilize natural dyes, anthocyanins. The ultraviolet-visible (UV-vis) spectrum of anthocyanin extract solutions and agar/potato starch films with anthocyanins showed color variations to different pH values (pH 2.0-10.0). Fourier transform infrared (FT-IR) and UV-vis region spectra showed compatibility between agar, starch, and anthocyanin extracts. Color variations of pH indicator films were measured by a colorimeter after immersion in different pH buffers. An application test was conducted for potential use as a meat spoilage sensor. The pH indicator films showed pH changes and spoilage point of pork samples, changing from red to green. Therefore, the developed pH indicator films could be used as a diagnostic tool for the detection of food spoilage.

  8. Physical and biological treatments of polyethylene-rice starch plastic films

    Energy Technology Data Exchange (ETDEWEB)

    El-Naggar, Manal M.A., E-mail: mmelnaggar@yahoo.com [Microbiology Lab., National Institute of Oceanography and Fisheries, Alexandria (Egypt); Farag, Magdy Gh. [Development Plastic Center, Victoria, Alexandria (Egypt)

    2010-04-15

    This study aimed to produce an industrial applicable thermo-stable {alpha}-amylase from marine Bacillus amyloliquefaciens which isolated and selected according to its significant enzyme production. The effect of different pH values and temperatures on the bacterial growth and the enzyme production was estimated using an experimental statistical design; maximum amylase production and bacterial growth was obtained at pH 7.0 and 50 deg. C. Some biodegradable polyethylene rice starch plastic films (PERS-P) were manufactured using 0, 2.5, 5, 7.5 and 10% starch concentrations. The biodegradability (reduction in the plastic elongation%) was tested using the exposure to UV radiation at {lambda}{sub 300-400nm} (intensity of about 1000 W/m{sup 2}) and the produced B. amyloliquefaciens thermo-stable {alpha}-amylase. A significant reduction in the elongation% of these biodegradable plastics was observed in both cases especially on testing the 10% PERS-P; they showed a reduction of 26% and 20%, respectively, compared to the untreated plastic films (180 {+-} 5).

  9. Characterization of starch nanoparticles

    Science.gov (United States)

    Szymońska, J.; Targosz-Korecka, M.; Krok, F.

    2009-01-01

    Nanomaterials already attract great interest because of their potential applications in technology, food science and medicine. Biomaterials are biodegradable and quite abundant in nature, so they are favoured over synthetic polymer based materials. Starch as a nontoxic, cheap and renewable raw material is particularly suitable for preparation of nanoparticles. In the paper, the structure and some physicochemical properties of potato and cassava starch particles of the size between 50 to 100 nm, obtained by mechanical treatment of native starch, were presented. We demonstrated, with the aim of the Scanning Electron Microscopy (SEM) and the non-contact Atomic Force Microscopy (nc-AFM), that the shape and dimensions of the obtained nanoparticles both potato and cassava starch fit the blocklets - previously proposed as basic structural features of native starch granules. This observation was supported by aqueous solubility and swelling power of the particles as well as their iodine binding capacity similar to those for amylopectin-type short branched polysaccharide species. Obtained results indicated that glycosidic bonds of the branch linkage points in the granule amorphous lamellae might be broken during the applied mechanical treatment. Thus the released amylopectin clusters could escape out of the granules. The starch nanoparticles, for their properties qualitatively different from those of native starch granules, could be utilized in new applications.

  10. Produção de snacks funcionais à base de farinha de soja e polvilho azedo Production of functional snacks from soybean flour and sour cassava starch

    Directory of Open Access Journals (Sweden)

    Magali Leonel

    2010-06-01

    Full Text Available Este trabalho teve por objetivo avaliar o efeito da temperatura de extrusão e da porcentagem de farinha de soja sobre a expansão (IE, o índice de absorção de água (IAA, o índice de solubilidade em água (ISA, a cor (L*, a* e b* e a dureza de biscoitos extrusados. O processo de extrusão seguiu o delineamento central composto rotacional para dois fatores, totalizando 11 tratamentos. Os resultados obtidos mostraram que a temperatura e a porcentagem de farinha de soja tiveram efeitos significativos sobre as propriedades físicas dos produtos. Nas condições intermediárias de temperatura e baixa porcentagem de farinha de soja (10%, é possível obter biscoitos funcionais de mandioca com elevada expansão, índices intermediários de absorção e solubilidade em água, cor clara e baixa dureza.This study aimed to evaluate the effect of the extrusion temperature and the percentage of soybean flour in mixes on the expansion index (EI, water absorption index (WAI, water solubility index(WSI; color (L *, a *, b * and hardness of extruded sour cassava snacks. The extrusion process followed the rotational central composite design for two factors, totalizing 11 treatments. The results showed that the extrusion temperature and percentage of soybean flour in mixes had significant effects on the physical properties of products. Under the conditions of intermediate temperature and low percentage of soybean meal is possible to obtain function cassava snacks with high expansion, intermediate index of absorption and solubility in water, light color and low hardness.

  11. Structural characterization of magnetic cassava-starch microspheres and their application in adsorption of lysozyme%木薯淀粉磁性微球的结构表征及其对溶菌酶的吸附性能

    Institute of Scientific and Technical Information of China (English)

    蓝平; 何日梅; 封余贤; 李庭龙; 熊根; 韦金峦; 梁佩珠; 廖安平

    2016-01-01

    The magnetic cassava starch microspheres have been prepared using Fe3O4 and cassava starch as starting materials. Fourier transform infrared spectrum,X-ray diffraction,thermal analyzer, scanning electron microscope,laser granulometer,and magnetic balance were used to characterize the product. The adsorption behavior of lysozyme on these microspheres was studied. The influence of magnetic microsphere dosage,solution pH,adsorption temperature and time on the adsorption efficiency was evaluated by single factor experiments. The results showed that magnetic starch microspheres contain 19.71% of Fe3O4,withD50 (median diameter) of 15.40µm,and magnetic susceptibility of 1.571×10−3cm3/g . When the dosage of microspheres was 1.25g,with solution pH value of 10,adsorption temperature of 25℃,adsorption time of 80min,the best adsorption efficiency of lysozyme on the microsphere was 84.67%. Based on the correlation coefficientR2,the adsorption rate can be better described by pseudo-second-order kinetics(R2=0.99997) than by pseudo-first-order kinetics (R2=0.99174),and the particle diffusion model(R2=0.69996).%磁性微球是高分子材料与磁性物质通过一定作用复合而成的一类具有特殊功能的磁性高分子微球。以木薯淀粉为原材料,复合共沉淀法制备的改性磁流体Fe3O4,采用两步法(化学交联法)制备木薯淀粉磁性微球。利用傅里叶变换红外光谱仪、X射线衍射仪、同步热分析仪、扫描电镜、激光粒度仪、磁天平等对其性能及结构进行表征并研究其对溶菌酶的吸附行为。通过单因素法考察磁性微球用量、溶液pH值、吸附温度、吸附时间对吸附率的影响,并采用准一级动力学模型和准二级动力学模型研究其吸附动力学。结果表明:制备的木薯淀粉磁性微球Fe3O4含量为19.71%,D50(中位径)为15.40µm,磁化率为1.571×10−3cm3/g,形貌规整;在微球用量为1.25g,溶液pH=10,吸附温度为25

  12. Functional properties of extruded nano composites based on cassava starch, polyvinyl alcohol and montmorillonite; Propriedades funcionais de nanocompositos extrusados de amido de mandioca, alcool polivinilico e montmorilonita

    Energy Technology Data Exchange (ETDEWEB)

    Debiagi, Flavia; Mali, Suzana [Departamento de Bioquimica e Biotecnologia, Universidade Estadual de Londrina, PR (Brazil)

    2011-07-01

    The objectives of this work were to produce expanded nano composites (foams) based on starch, PVA and sodium montmorillonite and characterize them according to their expansion index (EI), density, water absorption capacity (WSC), mechanical properties and X-ray diffraction. The nano composites were prepared in a single-screw extruder using different starch contents (97.6 - 55.2 g/100 g formulation), PVA (0 - 40 g/100 g formulation), unmodified nano clay - Closite - Na (0 - 4. 8 g/100 g formulation) and glycerol (20 g/100 g formulation) as plasticizer. The addition of montmorillonite and PVA resulted in an increase of EI and a decrease of density of the samples, and reduced WSC and increased the mechanical strength of the foams. Through the analysis of X-ray diffraction can be observed that the addition of montmorillonite led to production of intercalated nano composites in all samples. (author)

  13. Promoting Cassava as an Industrial Crop in Ghana: Effects on Soil Fertility and Farming System Sustainability

    Directory of Open Access Journals (Sweden)

    S. Adjei-Nsiah

    2012-01-01

    Full Text Available Cassava is an important starchy staple crop in Ghana with per capita consumption of 152.9 kg/year. Besides being a staple food crop, cassava can be used as raw material for the production of industrial starch and ethanol. The potential of cassava as an industrial commercial crop has not been exploited to a large extent because of perceptions that cassava depletes soils. Recent finding from field studies in the forest/savannah transitional agroecological zone of Ghana indicates that when integrated in the cropping system as a form of rotation, cassava contributes significantly to maintenance of soil fertility, and thus large scale production of cassava for industrial use can contribute to poverty reduction in an environmentally responsive way. This paper discusses the role of cassava cultivation in soil fertility management and its implication for farming system sustainability and industrialization.

  14. Cloning and characterization of a tuberous root-specific promoter from cassava (Manihot esculenta Crantz)

    NARCIS (Netherlands)

    Koehorst-van Putten, H.J.J.; Wolters, A.M.A.; Pereira-Bertram, I.J.; Berg, H.; Krol, van der A.R.; Visser, R.G.F.

    2012-01-01

    In order to obtain a tuberous root-specific promoter to be used in the transformation of cassava, a 1,728 bp sequence containing the cassava granule-bound starch synthase (GBSSI) promoter was isolated. The sequence proved to contain light- and sugar-responsive cis elements. Part of this sequence (1,

  15. Biodegradable and non-retrogradable eco-films based on starch-glycerol with citric acid as crosslinking agent.

    Science.gov (United States)

    Seligra, Paula González; Medina Jaramillo, Carolina; Famá, Lucía; Goyanes, Silvia

    2016-03-15

    Biodegradable and non-retrogradable starch-glycerol based films were obtained using citric acid (CA) as crosslinking agent at 75°C. This material allowed decreasing water vapor permeability (WVP) more than 35%, remained amorphous for at least 45 days as a result of the network formed by the CA that avoided starch retrogradation and maintained the degradability in compost, occurring only six days after the films without citric acid. A simulation of the gelatinization process of starch-glycerol with and without CA, using a differential thermal analysis device, showed that the system with CA completed the gelatinization 5°C before than the other and, CA first reacted with glycerol and then starch-glycerol-CA reaction occurred. The temperature at which the gelatinization process was carried out was critical to obtain the best results. An increase of gelatinization process temperature at 85°C in system with CA, led to a worsening on WVP and its integrity after a swelling process with dimethylsulphoxide (DMSO), compared to the films processed at 75°C.

  16. Direct fermentation of gelatinized cassava starch to acetone, butanol, and ethanol using Clostridium acetobutylicum mutant obtained by atmospheric and room temperature plasma.

    Science.gov (United States)

    Li, Han-guang; Luo, Wei; Wang, Qiang; Yu, Xiao-bin

    2014-04-01

    The mutant strain designated as ART18, obtained from the wild-type strain Clostridium acetobutylicum PW12 treated by atmospheric and room temperature plasma, showed higher solvent tolerance and butanol production than that of the wild-type strain. The production of butanol was 11.3 ± 0.5 g/L, 31 % higher than that of the wild-type strain when it was used for acetone, butanol, and ethanol fermentation in P2 medium. Furthermore, the effects of cassava flour concentration, pH regulators, and vitamins on the ABE production were also investigated. The highest butanol production of 15.8 ± 0.8 g/L and butanol yield (0.31 g/g) were achieved after the above factors were optimized. When acetone, butanol, and ethanol fermentation by ART18 was carried out in a 15-L bioreactor, the butanol production, the productivity of butanol, and the total solvent were 16.3 ± 0.9, 0.19, and 0.28 g/L(/)h, respectively. These results indicate that ART18 is a promising industrial producer in ABE fermentation.

  17. Development Trend of Cassava Industry and Market Analysis in China%我国木薯产业的发展趋势与市场分析①

    Institute of Scientific and Technical Information of China (English)

    文玉萍

    2014-01-01

    Expatiating on domestic current progress in cassava planting, cassava starch (modified starch) and cassava alcohol, and prospects of their future development tendency.%对我国的木薯种植,木薯淀粉(变性淀粉),木薯酒精行业的发展现状进行阐述,展望其发展趋势。

  18. Preparation of indigestible pyrodextrins from different starch sources.

    Science.gov (United States)

    Laurentin, Alexander; Cárdenas, Marité; Ruales, Jenny; Pérez, Elevina; Tovar, Juscelino

    2003-08-27

    Starch-modifying processes, such as pyrodextrinization, are potential ways to alter the nutritional features of this polysaccharide. A widely used method for pyrodextrinizing maize starch was also applied to lentil, sorghum, cocoyam, sagu, and cassava starches, and the in vitro digestibility of the products was evaluated. Pyrodextrins were produced by heating starch at 140 degrees C for 3 h, with catalytic amounts of HCl. The enzymatically available starch content of all preparations decreased by 55-65% after modification. Thus, pyrodextrinization seems to be an effective way to produce indigestible glucans from different starches. Pyrodextrins obtained were complex mixtures of starch derivatives with a wide range of molecular weight as estimated by gel filtration chromatography. Both their molecular weight profiles and contents of indigestible fractions varied with starch source. Experiments with lentil and cassava starches showed that changing dextrinization conditions also affects the susceptibility to enzymatic hydrolysis of the product.

  19. Physical and Antimicrobial Properties of Starch-PVA Blend Films as Affected by the Incorporation of Natural Antimicrobial Agents

    Directory of Open Access Journals (Sweden)

    Amalia Cano

    2015-12-01

    Full Text Available In this work, active films based on starch and PVA (S:PVA ratio of 2:1 were developed by incorporating neem (NO and oregano essential oils (OEO. First, a screening of the antifungal effectiveness of different natural extracts (echinacea, horsetail extract, liquid smoke and neem seed oil against two fungus (P. expansum and A. niger was carried out. The effect of NO and OEO incorporation on the films’ physical and antimicrobial properties was analyzed. Only composite films containing OEO exhibited antibacterial and antifungal activity. Antibacterial activity occurred at low OEO concentration (6.7%, while antifungal effect required higher doses of OEO in the films. Incorporation of oils did not notably affect the water sorption capacity and water vapor barrier properties of S-PVA films, but reduced their transparency and gloss, especially at the highest concentrations. The mechanical response of the S-PVA films was also negatively affected by oil incorporation but this was only relevant at the highest oil ratio (22%. S-PVA films with 6.7% of OEO exhibited the best physical properties, without significant differences with respect to the S-PVA matrix, while exhibiting antibacterial activity. Thus, the use of OEO as a natural antimicrobial incorporated into starch-PVA films represents a good and novel alternative in food packaging applications.

  20. Physical and Antimicrobial Properties of Starch-PVA Blend Films as Affected by the Incorporation of Natural Antimicrobial Agents

    Science.gov (United States)

    Cano, Amalia; Cháfer, Maite; Chiralt, Amparo; González-Martínez, Chelo

    2015-01-01

    In this work, active films based on starch and PVA (S:PVA ratio of 2:1) were developed by incorporating neem (NO) and oregano essential oils (OEO). First, a screening of the antifungal effectiveness of different natural extracts (echinacea, horsetail extract, liquid smoke and neem seed oil) against two fungus (P. expansum and A. niger) was carried out. The effect of NO and OEO incorporation on the films’ physical and antimicrobial properties was analyzed. Only composite films containing OEO exhibited antibacterial and antifungal activity. Antibacterial activity occurred at low OEO concentration (6.7%), while antifungal effect required higher doses of OEO in the films. Incorporation of oils did not notably affect the water sorption capacity and water vapor barrier properties of S-PVA films, but reduced their transparency and gloss, especially at the highest concentrations. The mechanical response of the S-PVA films was also negatively affected by oil incorporation but this was only relevant at the highest oil ratio (22%). S-PVA films with 6.7% of OEO exhibited the best physical properties, without significant differences with respect to the S-PVA matrix, while exhibiting antibacterial activity. Thus, the use of OEO as a natural antimicrobial incorporated into starch-PVA films represents a good and novel alternative in food packaging applications.

  1. Effect of film multi-scale structure on the water vapor permeability in hydroxypropyl starch (HPS)/Na-MMT nanocomposites.

    Science.gov (United States)

    Liu, Siyuan; Cai, Panfu; Li, Xiaoxi; Chen, Ling; Li, Lin; Li, Bing

    2016-12-10

    To improve the water vapor resistance of starch-based films, Na-MMT (Na-montmorillonite) as nanofillers were fabricated into hydroxypropyl starch and the multi-scale structural changes (including intermolecular interaction, short-range conformation, long-range ordered structure and the aggregated structure of the film) were revealed. The elongation of the water vapor molecule pathway by tortuous path is generally recognized as the main reason for the improvement of water resistance. However this study observed the lowest water vapor permeability (WVP) was at the 3% Na-MMT/hydroxypropyl starch (HPS) ratio instead of 5% even nanofillers were partially exfoliated at both ratio. Except for the "tortuous path" caused by nanofillers, this observation proposed that the short-range conformation of HPS chains, long-range ordered structure and the aggregated structure likely influenced the water barrier property. The relationship between WVP and multi-scale structure of the film was investigated. The results suggested that a good balance of short-range conformationin the amorphous region, long-range ordered structure and the aggregated structure of the film was required for the improvement of water vapor barrier property.

  2. Antibacterial, antioxidant and optical properties of edible starch-chitosan composite film containing Thymus kotschyanus essential oil

    Directory of Open Access Journals (Sweden)

    Tooraj Mehdizadeh

    2012-09-01

    Full Text Available Thyme Essential oils (EO with antimicrobial and antioxidant properties are widely used in pharmaceutical, cosmetic, and perfume industry. It is also used for flavoring and preservation of several foods. Nowadays, packaging research is receiving a considerable attention due to the development of eco-friendly materials made from natural polymers such as starch and chitosan. In this study Thymus kotschyanus EO concentrations ranging from 0 to 2.0%, incorporated in starch-chitosan composite (S-CH film were used. Antimicrobial and antioxidant properties significantly increased with the incorporation of EO (p < 0.05. Incorporating EO, increased total color differences (DE, yellowness index (YI and whiteness index (WI which were significantly higher than control and its transparency was reduced. Our results pointed out that the incorporation of Thymus kotschyanus EO as a natural antibacterial agent has potential for using the developed film as an active packaging.

  3. Effect of electron beam irradiation on the biodegradability of aromatic aliphatic copolyester film and their blend with corn starch

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Leonardo G. Andrade e; Poveda, Patricia N.S., E-mail: lgasilva@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Rezende, Maira L.; Rosa, Derval S. [Universidade Sao Francisco, Itatiba, SP (Brazil)

    2009-07-01

    Biodegradable and green plastics have been studied in the last years. The aim of this paper is to study the effect of electron beam irradiation on the biodegradability of aromatic aliphatic copolyester film and their blend with corn starch. The samples were irradiated at different doses 10 and 40 kGy in a linear accelerator. The biodegradability of the materials was evaluated by two methods: soil simulated and enzymatic. In the method enzymatic when it was used alpha-amylase, the irradiated samples presented faster biodegradation than the references non irradiated. The blend of aromatic aliphatic copolyester with corn starch (Ecobras{sup R}) irradiated presented a bigger biodegradability than the aromatic aliphatic copolyester (Ecoflex{sup R}) film in both methods studied. (author)

  4. Analysis of heterogeneity of Copia-like retrotransposons in the genome of cassava (Manihot esculenta Crantz).

    Science.gov (United States)

    Gbadegesin, Micheal A; Beeching, John R

    2011-12-20

    Retrotransposons are ubiquitous in eukaryotic genomes and now proving to be useful genetic tools for genetic diversity and phylogenetic analyses, especially in plants. In order to assess the diversity of Ty1/Copia-like retrotransposons of cassava, we used PCR primers anchored on the conserved domains of reverse transcriptases (RTs) to amplify cassava Ty1/Copia-like RT. The PCR product was cloned and sequenced. Sequences analysis of the clones revealed the presence of 69 families of Ty1/Copia-like retrotransposon in the genome of cassava. Comparative analyses of the predicted amino acid sequences of these clones with those of other plants showed that retroelements of this class are very heterogeneous in cassava. Cassava is widely grown for its edible roots in the tropical and subtropical regions of the world. Cassava roots, though poor in protein, are rich in starch (makes up about 80% of the dry matter), vitamin C, carotenes, calcium and potassium. It has a great commercial importance as a source of starch and starch based products. Realizing the importance of cassava, it stands out as a crop to benefit from biotechnology development. Heterogeneity of Mecops (Manihot esculenta copia-like Retrotransposons) showed that they may be useful for genetic diversity and phylogenetic analyses of cassava germplasm.

  5. STARCH/PULP-FIBER BASED PACKAGING FOAMS AND CAST FILMS CONTAINING ALASKAN FISH BY-PRODUCTS (WASTE

    Directory of Open Access Journals (Sweden)

    Syed H. Imam

    2008-08-01

    Full Text Available Baked starch/pulp foams were prepared from formulations containing zero to 25 weight percent of processed Alaskan fish by-products that consisted mostly of salmon heads, pollock heads, and pollock frames (bones and associated remains produced in the filleting operation. Fish by-products thermoformed well along with starch and pulp fiber, and the foam product (panels exhibited useful mechanical properties. Foams with all three fish by-products, ranging between 10 and 15 wt%, showed the highest flexural modulus (500-770 Mpa. Above 20% fiber content, the modulus dropped considerably in all foam samples. Foam panels with pollock frames had the highest flexural modulus, at about 15% fiber content (770 Mpa. Foams with salmon heads registered the lowest modulus, at 25% concentration. Attempts were also made to cast starch-glycerol-poly (vinyl alcohol films containing 25% fish by-product (salmon heads. These films showed a tensile strength of 15 Mpa and elongation at break of 78.2%. All foams containing fish by-product degraded well in compost at ambient temperature (24oC, loosing roughly between 75-80% of their weight within 7 weeks. The films degraded at a much higher rate initially. When left in water, foams prepared without fish by-product absorbed water much more quickly and deteriorated faster, whereas, water absorption in foams with fish by-product was initially delayed and/or slowed for about 24 h. After this period, water absorption was rapid.

  6. Preparation and Application of Starch/Polyvinyl Alcohol/Citric Acid Ternary Blend Antimicrobial Functional Food Packaging Films

    Directory of Open Access Journals (Sweden)

    Zhijun Wu

    2017-03-01

    Full Text Available Ternary blend films were prepared with different ratios of starch/polyvinyl alcohol (PVA/citric acid. The films were characterized by field emission scanning electron microscopy (FE-SEM, thermogravimetric analysis, as well as Fourier transform infrared (FTIR analysis. The influence of different ratios of starch/polyvinyl alcohol (PVA/citric acid and different drying times on the performance properties, transparency, tensile strength (TS, water vapor permeability (WVP, water solubility (WS, color difference (ΔE, and antimicrobial activity of the ternary blends films were investigated. The starch/polyvinyl alcohol/citric acid (S/P/C1:1:0, S/P/C3:1:0.08, and S/P/C3:3:0.08 films were all highly transparent. The S/P/C3:3:0.08 had a 54.31 times water-holding capacity of its own weight and its mechanical tensile strength was 46.45 MPa. In addition, its surface had good uniformity and compactness. The S/P/C3:1:0.08 and S/P/C3:3:0.08 showed strong antimicrobial activity to Listeria monocytogenes and Escherichia coli, which were the food-borne pathogenic bacteria used. The freshness test results of fresh figs showed that all of the blends prevented the formation of condensed water on the surface of the film, and the S/P/C3:1:0.08 and S/P/C3:3:0.08 prevented the deterioration of figs during storage. The films can be used as an active food packaging system due to their strong antibacterial effect.

  7. Chemical, physical and morphometric properties of Peruvian carrot (Arracacia xanthorrhiza B.) starch.

    Science.gov (United States)

    Pérez, E E; Borneo, R; Melito, C G; Tovar, J

    1999-01-01

    Starch was isolated from Peruvian carrot (PC)--or arracacha--(Arraccacia xanthorrhiza B.) roots. Its chemical, physical, physicochemical and granular structural properties were compared to those of commercial cassava starch. Scanning electron microscopy revealed a granular size for PC starch ranging between 4 and 26 microns in diameter, with spherical and truncated-egg shapes. PC and cassava starches were similar regarding gross chemical composition and basic physical characteristics but differed in pasting properties, with PC starch showing lower breakdown and consistency indices. The two starches also showed different water absorption and solubility patterns.

  8. Characterization of cassava clones produced in Roraima for in natura consumption. = Caracterização e identificação de clones de mandioca produzidos em Roraima para o consumo in natura.

    Directory of Open Access Journals (Sweden)

    Natália Trajano de Oliveira

    2011-12-01

    Full Text Available The objective of this study was to characterize and identify cassava clones produced in Roraima State, Brazil, for human consumption. There was the planting of six clones of cassava (Aciolina, Pão, Pão-do-Chile, Água Morna, Enxuta and Amazonas, in double rows, following the spacing of 2.0 m x 0.8 m x 0.8 m, total of 8,928 plants ha-1 . It was used randomized blocks experimental design with four replications. At eight months after planting was carried out to harvest the roots, being evaluated for hydrocyanic acid, starch content by the method of hydrostatic balance and artisanal mining, ability to release the film and bark, bark color and flesh color raw. The cassava clones were classified according to HCN content in: Mansi (Enxuta and Pão-do-Chile, intermediate (Aciolina and Água Morna and Brava (Pão and Amazonas. The starch obtained by the method of hydrostatic balance overestimates the starch content by the method artisanal mining. The Aciolina clone stood out among the clones for human consumption, it is also recommended for industrial use. The Pão and Amazonas clones have restrictions for both human consumption and for industrial used.

  9. Cassava, yam, sweet potato and ñampi starch: functional properties and possible applications in the food industry. Harinas y almidones de yuca, ñame, camote y ñampí: propiedades funcionales y posibles aplicaciones en la industria alimentaria.

    Directory of Open Access Journals (Sweden)

    Pedro Vargas Aguilar

    2013-03-01

    Full Text Available A technical review was conducted to related physical and chemical properties of flours and starches from cassava, yams, taro and sweet potato. Amyloseamylopectin content, viscosity, nutritional value and fiber, were studied to relate them with starch functional properties. A relationship was obtained between amylose-amylopectin, viscosity and fiber content with the digestibility of those starches and the glycemic index values. The use of fermentation to enhance the nutritional value of these starches is known. Starch fermentation allows the production of gluten-free bread and energy drinks as an option to diversify products. It was also observed the relationship between the starch viscosity and the fat absorption in fried foods.Se realizó una revisión de las características fisicoquímicas de las harinas y almidones de yuca, ñame, ñampí y camote, tales como el contenido de amilosa-amilopectina, la viscosidad, el valor nutricional y la fibra, con el fin de relacionarlas con sus propiedades funcionales y técnico-funcionales. Se obtuvo una relación entre el contenido de amilosa-amilopectina, viscosidad y contenido de fibra en la digestibilidad de estos almidones y los valores de índice glicémico. Se encontró que es posible introducir modificaciones por medio de la fermentación para mejorar el valor funcional de estos almidones. La fermentación permite elaborar pan sin gluten y bebidas energéticas como nuevas opciones de productos. También se encontró que existe una relación entre la viscosidad de los almidones y la disminución de absorción de la grasa en frituras.

  10. Performance properties and antibacterial activity of crosslinked films of quaternary ammonium modified starch and poly(vinyl alcohol).

    Science.gov (United States)

    Sekhavat Pour, Zahra; Makvandi, Pooyan; Ghaemy, Mousa

    2015-09-01

    There has been a growing interest in developing antibacterial polymeric materials. In the present work, novel antibacterial cross-linked blend films were prepared based on polyvinyl alcohol (PVA) and quaternary ammonium starch (ST-GTMAC) using citric acid (CA) as plasticizer and glutaraldehyde (GA) as cross-linker. The ST-GTMAC was successfully synthesized from reaction between water-soluble oxidized starch and glycidyltrimethylammonium chloride (GTMAC). The effect of ST-GTMAC, CA and GA contents on the swelling, solubility, mechanical and thermal properties of the films was investigated. It was found that incorporation of ST-GTMAC reduced UV-transmittance and provided antibacterial properties, increasing GA content increased tensile strength and decreased solubility and swelling degree of the films, while CA acted as plasticizer when its concentration was above 10 wt%. The results showed that ST-GTMAC/PVA/CA/GA film has fair antibacterial activity against Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. These results suggest that the prepared film might be used as potential antibacterial material in medical and packaging applications.

  11. Effect of plasticizer type and concentration on physical properties of biodegradable films based on sugar palm (arenga pinnata) starch for food packaging

    OpenAIRE

    Sanyang, M. L.; Sapuan, S. M.; Jawaid, M.; M. R. Ishak; J. Sahari

    2015-01-01

    In this study, sugar palm starch (SPS) films were developed using glycerol (G), sorbitol (S) or their combination (GS) as plasticizers at the ratio of 15, 30 and 45 (wt)% using casting technique. The addition of plasticizers to SPS film-forming solutions helped to overcome the brittle and fragile nature of unplasticized SPS films. Increased plasticizer concentration resulted to an increase in film thickness, moisture content and solubility. On the contrary, density and water...

  12. Effect of Plasticizer Type and Concentration on Tensile, Thermal and Barrier Properties of Biodegradable Films Based on Sugar Palm (Arenga pinnata Starch

    Directory of Open Access Journals (Sweden)

    Muhammed L. Sanyang

    2015-06-01

    Full Text Available The use of starch based films as a potential alternative choice to petroleum derived plastics is imperative for environmental waste management. This study presents a new biopolymer (sugar palm starch for the preparation of biodegradable packaging films using a solution casting technique. The effect of different plasticizer types (glycerol (G, sorbitol (S and glycerol-sorbitol (GS combination with varying concentrations (0, 15, 30 and 45, w/w% on the tensile, thermal and barrier properties of sugar palm starch (SPS films was evaluated. Regardless of plasticizer types, the tensile strength of plasticized SPS films decreased, whereas their elongation at break (E% increased as the plasticizer concentrations were raised. However, the E% for G and GS-plasticized films significantly decreased at a higher plasticizer concentration (45% w/w due to the anti-plasticization effect of plasticizers. Change in plasticizer concentration showed an insignificant effect on the thermal properties of S-plasticized films. The glass transition temperature of SPS films slightly decreased as the plasticizer concentration increased from 15% to 45%. The plasticized films exhibited increased water vapor permeability values from 4.855 × 10−10 to 8.70 × 10−10 g·m−1·s−1·Pa−1, irrespective of plasticizer types. Overall, the current study manifested that plasticized sugar palm starch can be regarded as a promising biopolymer for biodegradable films.

  13. Effect of antimicrobial on mechanical, barrier and optical properties of corn starch based self-supporting edible film

    Directory of Open Access Journals (Sweden)

    Tanima Chowdhury

    2013-10-01

    Full Text Available Antimicrobials like potassium sorbate, sodium propionate, and benzoic acid were incorporated in corn starch based formulation to investigate their effect on mechanical, water vapour barrier and optical properties of the developed self supporting edible film. The film was prepared by casting technique. When incorporated at 1.40% and above, potassium sorbate decreased the tensile strength (about 22% and increased the elongation (about 55% of control film; whereas, it increased the water vapour permeability by 15% only when added at 2.66%. At 2.66%, benzoic acid reduced the tensile strength by 24% and sodium propionate increased elongation by 17%. These two antimicrobials did not change the water vapour permeability. However, all the three antimicrobials adversely affected the optical properties by decreasing the whiteness index, increasing yellowness index, and reducing the surface gloss, with potassium sorbate showing the maximum effect. Among the three antimicrobials, sodium propionate appeared to be the best with minimum deterioration of film properties.

  14. Effect of natamycin, nisin and glycerol on the physicochemical properties, roughness and hydrophobicity of tapioca starch edible films.

    Science.gov (United States)

    Ollé Resa, Carolina P; Jagus, Rosa J; Gerschenson, Lía N

    2014-07-01

    In this paper, films based on tapioca starch and containing nisin, natamycin and glycerol were characterized in relation to their physicochemical properties, roughness and hydrophobicity. The content of glycerol affected the mechanical properties of the films studied and the roughness and it was observed an increase in WVP with the increase in glycerol content. The addition of antimicrobials affected the mechanical properties, being nisin the one that produced the greater decrease in the Young modulus. The color was highly affected by the joint presence of natamycin and nisin, which increased the yellow index. The contact angle increased with antimicrobial addition indicating a decrease in hydrophilicity. Nisin also affected the roughness of the films. Water vapor permeability was slightly reduced by the presence of natamycin. It was observed that water vapor permeability and contact angle were correlated with the roughness of the films.

  15. Physical properties of snacks made from cassava leaf flour

    Directory of Open Access Journals (Sweden)

    Adriana Cristina Ferrari

    2014-02-01

    Full Text Available The food industry is continually growing with new products becoming available every year. Extrusion combines a number of unit operations in one energy efficient rapid continuous process and can be used to produce a wide variety of snacks foods. The objective of this study was to evaluate the effect of extrusion temperature, screw speed, and amount of cassava leaf flour mixed with cassava starch on the physical properties of extruded snacks processed using a single screw extruder. A central composite rotational design, including three factors with 20 treatments, was used in the experimental design. Dependent variables included the expansion index, specific volume, color, water absorption index, and water solubility index. Among the parameters examined, the amount of cassava leaf flour and extrusion temperature showed significant effects on extruded snack characteristics. Mixtures containing 10% of cassava leaf flour extruded at 100°C and 255 rpm shows favorable levels of expansion, color, water absorption index, and water solubility index.

  16. CHARACTERISATION OF CASSAVA FIBRE FOR USE AS A BIOMATERIAL

    Directory of Open Access Journals (Sweden)

    Lois Larbie

    2012-07-01

    Full Text Available In this study we investigate the cytotoxicity of de-starched cassava fibre granules and fine powder using human peripheral blood mononuclear cells (PBMC and examine changes in the composition of Simulated Body Fluid (SBF resulting from immersion of cassava fibre samples. The purpose of the study was to characterise cassavafibre for possible biomaterial applications. Preliminary results indicate insignificant cytotoxic effects on PBMCs with cassava sample concentrations of 0.1g/ml, 0.025g/ml and 0.00625g/ml. Additionally there was little or no significant change in Na, K, Mg, Cl, Ca, Mn, and Cu concentrations upon immersion in SBF as observed over a one week period at a temperature of 37°C. These initial results suggest cassava fibre may be considered for biomaterial applications following more extensive characterisation.

  17. Thermal and pasting properties of cassava starch-dehydrated orange pulp blends Propriedades térmicas e de pasta de misturas de fécula de mandioca e polpa cítrica

    Directory of Open Access Journals (Sweden)

    Magali Leonel

    2011-06-01

    Full Text Available Instant mixtures are easy to prepare and frequently present functional appeals. A quality parameter for instant mixtures is their rheological behavior. This study aimed at evaluating the effects of extrusion parameters on the pasting properties of cassava (Manihot esculenta L. starch and dehydrated orange (Citrus sinensis (L. Osbeck pulp mixtures. The variable parameters were moisture of mixtures (12.5 to 19%, barrel temperature (40 to 90ºC and screw rotation (170 to 266 rpm. The extruded mixtures did not show gelatinization enthalpy. Moisture had the greatest effect on paste properties. The initial pasting viscosity (before heating of RVA (Rapid visco analyzer is the most relevant parameter to instant mixtures. The highest cold viscosity values were obtained when mixtures were extruded under high moisture and high screw speed. High moisture (19.5%, intermediate temperature (65ºC and screw speed (218 rpm led to extruded mixtures production with low component degradation.Misturas instantâneas apresentam-se como produtos de fácil preparo e muitas vezes com apelos funcionais. Um parâmetro de qualidade nestas misturas é o comportamento reológico. Avaliou-se o efeito de parâmetros de extrusão sobre as propriedades de pasta de misturas de fécula de mandioca (Manihot esculenta L. e polpa de laranja (Citrus sinensis (L. Osbeck desidratada. A umidade das misturas (12.5 a 19%, a temperatura de extrusão (40 a 90ºC e a rotação da rosca (170 a 266 rpm foram considerados parâmetros variáveis. As misturas extrusadas não apresentaram entalpia de gelatinização. A umidade foi o fator de maior efeito sobre as propriedades de pasta. A viscosidade inicial (antes do aquecimento no RVA (Rapid visco analyzer é um dos parâmetros mais importantes para misturas instantâneas. Nas condições de elevada umidade e rotação da rosca são observadas as maiores viscosidades a frio. Condições de elevada umidade das misturas (19,5%, temperatura (65ºC e

  18. Silver nanoparticle-loaded chitosan-starch based films: Fabrication and evaluation of tensile, barrier and antimicrobial properties

    Energy Technology Data Exchange (ETDEWEB)

    Yoksan, Rangrong, E-mail: rangrong.y@ku.ac.th [Department of Packaging and Materials Technology, Faculty of Agro-Industry, Kasetsart University, 50 Paholyothin Rd., Ladyao, Jatujak, Bangkok 10900 (Thailand); Chirachanchai, Suwabun [Petroleum and Petrochemical College, Chulalongkorn University, Bangkok 10330 (Thailand)

    2010-07-20

    The fabrication of silver nanoparticles was accomplished by {gamma}-ray irradiation reduction of silver nitrate in a chitosan solution. The obtained nanoparticles were stable in the solution for more than six months, and showed the characteristic surface plasmon band at 411 nm as well as a positively charged surface with 40.4 {+-} 2.0 mV. The silver nanoparticles presented a spherical shape with an average size of 20-25 nm, as observed by TEM. Minimum inhibitory concentration (MIC) against E. coli, S. aureus and B. cereus of the silver nanoparticles dispersed in the {gamma}-ray irradiated chitosan solution was 5.64 {mu}g/mL. The silver nanoparticle-loaded chitosan-starch based films were prepared by a solution casting method. The incorporation of silver nanoparticles led to a slight improvement of the tensile and oxygen gas barrier properties of the polysaccharide-based films, with diminished water vapor/moisture barrier properties. In addition, silver nanoparticle-loaded films exhibited enhanced antimicrobial activity against E. coli, S. aureus and B. cereus. The results suggest that silver nanoparticle-loaded chitosan-starch based films can be feasibly used as antimicrobial materials for food packaging and/or biomedical applications.

  19. Efeito de fibras vegetais nas propriedades de compósitos biodegradáveis de amido de mandioca produzidos via extrusão Effects of vegetal fibers on properties of cassava starch biodegradable composites produced by extrusion

    Directory of Open Access Journals (Sweden)

    Flávia Debiagi

    2010-12-01

    Full Text Available A preocupação com o volume de lixo tem gerado interesse no desenvolvimento de embalagens biodegradáveis capazes de substituir, ao menos em parte, os plásticos convencionais sintéticos, como é o caso das embalagens de poliestireno expandido (Isopor. Ojvetivou-se,neste trabalho caracterizar, quanto ao índice de expansão (IE, densidade, índice de absorção em água (IAA, índice de solubilidade em água (ISA e cor (coordenadas L*, a* e b*, compósitos biodegradáveis expandidos produzidos via extrusão, a partir da mistura de amido de mandioca, glicerol (plastificante e dois tipos de fibras vegetais. Os compósitos foram preparados em extrusora mono-rosca, com três diferentes teores de fibras de aveia ou de cana-de-açúcar (0, 5 e 10 g/100 g amido, dois teores de umidade (18 e 26% e teor fixo de glicerol (20g/100 g sólidos. A adição das fibras não afetou significativamente o IE, a densidade e o IAA, porém diminuiu o ISA dos materiais, o que é uma vantagem, favorecendo a utilização das fibras no reforço dos compósitos. A adição de fibras levou ao escurecimento das amostras, com decréscimo da luminosidade (L* e, ainda, ao aumento nos valores dos parâmetros de cor a* e b*. Este estudo é passo fundamental para produção em escala industrial dos compósitos, que necessitam de condições de processo que forneçam resultados reprodutíveis de expansão e capacidade de absorção e solubilidade em água, propriedades de grande importância nesses produtos.The concern with the volume of waste has generated interest in the development of biodegradable packaging able to replace, at least in part, the conventional synthetic plastics, such as packs of expanded polystyrene (Isopor. This study aimed to characterize the expansion index, density, the water absorption index (WAI, water solubility index (WSI and color (coordinates L*, a* and b* of expanded biodegradable composites produced by extrusion, from the mixture cassava starch

  20. Process for producing cassava hydroxypropyl distarch phosphate and study of the properties

    Institute of Scientific and Technical Information of China (English)

    邵亚东; 王艳楠; 刘大伟; 刘晓成

    2014-01-01

    In the experiment, the nature cassava starch reacted with 1,2-epoxypropane and sodium trimetaphosphate under basic condition to producing hydroxypropyl distarch phosphate.At same time ,prepared to researching characteristics of the starch, including the substitution degree, gelatinization temperature and peak viscosity.

  1. Ocorrência do processo de fixação biológica de N2 atmosférico na fermentação de fécula de mandioca Biological fixation of atmospheric N2 in the initial phase of cassava starch fermentation

    Directory of Open Access Journals (Sweden)

    Luiz Ermindo Cavallet

    2006-09-01

    Full Text Available A fase inicial do processo de fermentação natural de fécula de mandioca apresenta a ocorrência de fermentação vigorosa em apenas 24 h, mesmo com o meio tendo uma relação carbono/nitrogênio muito alta. Assim, o nitrogênio necessário à formação da biomassa nos primeiros estágios da fermentação seria originário de fora do sistema via fixação biológica de N2 atmosférico, já que o teor protéico disponível na fécula de mandioca é muito baixo. Para verificar tal hipótese, foram feitos dois experimentos fundamentados no balanço de nitrogênio na suspensão com grânulos de fécula durante as primeiras 120 h do processo fermentativo, conduzido sob temperatura ambiente e sob temperatura controlada a 28 °C. Não foram detectados aumentos de nitrogênio na fase estudada, o que sugere a não existência do processo de fixação biológica de N2 atmosférico. Os resultados sugerem que a origem do nitrogênio para o processo fermentativo é a própria fécula, que, quando na forma de polvilho apresenta alta relação C/N, porém, quando em suspensão essa relação abaixa propiciando uma fermentação vigorosa em apenas 24 h.The initial phase of natural fermentation of cassava starch presents vigorous fermentation within the first 24 h and is characterized by a high ration of carbon/nitrogen. Consequently, the necessary nitrogen to the formation of biomass would be originated from outside of the system because the available protein content from cassava starch is very low and depending on biological fixation of atmospheric N2. To verify that hypothesis two essays were conducted with the nitrogen balance in the starch granule suspension during the initial 120 h of the fermentation process. The essays were set at room temperature and at the controlled temperature of 28 °C. No increase in the nitrogen content was detected suggesting that no involvement of atmospheric N2. Results suggest that the origin of the nitrogen to the

  2. Keratin/Polyvinyl Alcohol Blend Films Cross-Linked by Dialdehyde Starch and Their Potential Application for Drug Release

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    Yao Dou

    2015-03-01

    Full Text Available Feather keratin (FK extracted from feathers represents a valuable source of biodegradable and biocompatible polymer. The aim of this study was the development and characterization of blended films based on FK and polyvinyl alcohol (PVA cross-linked by dialdehyde starch (DAS for a potential drug release application. The compatibility of FK/PVA was improved when cross-linked by DAS: the relative crystallinity of the PVA/FK film slightly decreased, and the enthalpy value for the melting peak decreased by about 50% for the cross-linked films. The total soluble mass of all blend films in water was below 35% at 37 °C, indicating a good stability of the films in water. The results of the Rhodamine B dye (as a model drug release tests showed that the release rates decreased with increasing DAS content. DAS-induced cross-linking improves several important properties of the FK/PVA films, such as the compactness, the compatibility, and the stability in water. These improvements offer the potential to expand the application of FK films in the biomaterial field.

  3. Modification of water absorption capacity of a plastic based on bean protein using gamma irradiated starches as additives

    Energy Technology Data Exchange (ETDEWEB)

    Koeber, E. [Facultad de Ingenieria, Grupo de Ingenieria Bioquimica, Universidad de Buenos Aires, Paseo Colon 850, 1063, Buenos Aires (Argentina); Gonzalez, M.E. [Comision Nacional Energia Atomica, Av. Del Libertador 8250, Buenos Aires (Argentina); Gavioli, N. [Facultad de Ingenieria, Grupo de Ingenieria Bioquimica, Universidad de Buenos Aires, Paseo Colon 850, 1063, Buenos Aires (Argentina); Salmoral, E.M. [Facultad de Ingenieria, Grupo de Ingenieria Bioquimica, Universidad de Buenos Aires, Paseo Colon 850, 1063, Buenos Aires (Argentina)]. E-mail: esalmor@fi.uba.ar

    2007-01-15

    Some properties of a bean protein-starch plastic were modified by irradiation of the starch. Two kinds of starch from bean and cassava were irradiated with doses until 50 kGy before their inclusion in the composite. Water absorption of the resultant product was reduced by 36% and 60% in materials containing bean and cassava starch, respectively. A large decline in the elongation is observed till 10 kGy in both materials, while tensile strength diminished by 11% in the cassava composite.

  4. Produção de biscoitos extrusados de polvilho azedo com fibras: efeito de parâmetros operacionais sobre as propriedades físicas Production of snacks from sour cassava starch and fiber: effect of operational parameters on physical properties

    Directory of Open Access Journals (Sweden)

    Karina Fernandes de Camargo

    2008-09-01

    Full Text Available Neste trabalho buscou-se avaliar o efeito de parâmetros operacionais do processo de extrusão no desenvolvimento de biscoitos de polvilho com fibras, utilizando como matérias-primas o polvilho azedo e o farelo de mandioca. O processamento foi realizado em um extrusor mono-rosca, sendo considerados parâmetros variáveis: temperatura na 3ª zona de extrusão, umidade e porcentagem de fibras na mistura. Para analisar o efeito combinado das variáveis independentes nas características tecnológicas dos extrusados, utilizou-se o delineamento 'central composto rotacional' para três fatores. Os resultados obtidos mostraram efeitos significativos da umidade e porcentagem de fibras sobre o volume específico, sendo que a temperatura afetou os índices de solubilidade e absorção de água dos produtos extrusados. Condições de baixa temperatura (65 °C, baixa umidade (12% e baixo teor de fibras (The purpose of this work was to evaluate the effect of operational extrusion parameters on the production of cassava fiber snacks from sour cassava starch and cassava bagasse. Processing was carried out in a single-screw extruder, with temperature in the third extrusion zone, moisture and fiber percentage as independent variables. In order to evaluate the effect of the independent variables on technological characteristics of the snacks, a central composite design with three factors was used. The results showed significant effects of moisture and fiber percentage on specific volume, and extrusion temperature had effects on Water Solubility Index (WSI and Water Absorption Index (WAI. Products with good technological characteristics can be produced at low temperature (65 °C, low fiber (<4% and low moisture (12% conditions.

  5. Levels of replacing corn by cassava starch on performance and carcass characteristics of bulls finished in feedlot / Substituição do milho pelo resíduo da fecularia de mandioca no desempenho e nas características de carcaça de bovinos terminados em confinamento

    Directory of Open Access Journals (Sweden)

    Liandra Maria Abaker Bertipaglia

    2010-07-01

    Full Text Available This work was carried out to study the effects of replacing corn by different levels of cassava starch (0; 12.5; 22.8 and 32.7% on performance and carcass characteristics of bulls finished in feedlot. Thirtytwo crossbred bulls (½ Aberdeen Angus vs. ½ Nellore with 18 months old and 380 + 24 kg live weight were used in a completely randomized experimental design with four treatments and eight replications. The experiment was realized during 56 days with 14 days for adaptation. The complete diets [roughage (cottonseed hulls + concentrate (corn, soybean meal and cassava starch] were given at 8 am and at 4 pm to bulls. It was analyzed the initial weight (IW, final weight (FW, average daily gain (ADG, dry matter intake (DMI, feed conversion (FC, hot carcass dressing (HCD, fat thickness (FAT, Longissimus muscle area (LMA, leg length (LL and cushion thickness (CT. The IW, FW, ADG, FC, HCW, HCD, FT, LMA, LL and CT did not present difference (P > 0.05 among levels of replacing corn by cassava starch. The results obtained on performance and carcass traits using cassava starch by-products as a replacement for corn can be considered satisfactory.Objetivou-se com este trabalho avaliar o efeito do nível de substituição (0; 12,5; 22,8 e 32,7% do milho pelo resíduo de fecularia de mandioca sobre o desempenho e características de carcaça de bovinos em confinamento. Trinta e dois machos inteiros mestiços (½ Aberdeen Angus vs. ½ Nelore com 18 meses de idade e 380 + 24 kg de peso vivo foram utilizados em delineamento experimental inteiramente casualizado, com quatro tratamentos e oito repetições. O experimento foi desenvolvido durante 56 dias com 14 dias de adaptação. As rações completas [volumoso (casca de algodão + concentrado (milho, farelo de soja e resíduo desidratado de fecularia de mandioca] foram fornecidas às 8 h e 16 h aos animais. Foi analisado o peso inicial (PI, peso final (PF ganho médio diário (GMD, ingestão de matéria seca

  6. Production of a raw starch saccharifying amylase byBacillus alvei grown on different agricultural substrates.

    Science.gov (United States)

    Achi, O K; Nijoku-Obi, A N

    1992-03-01

    Maximum activity of the amylase ofBacillus alvei was attained after growth of the organism on sorghum starch. Rice, corn, yam, cassava and potato starch gave high enzyme activities as did soluble starch. Glucose, maltose and glycerol were less effective. Optimum conditions for both growth and enzyme production were pH 6.8 at 40°C.

  7. 新型环保木薯淀粉改性聚氨酯硬质泡沫塑料的制备及性能研究%Study on Preparation and Properties of New Environmental Friendly Cassava Starch Modified Polyurethane Foams

    Institute of Scientific and Technical Information of China (English)

    石骥; 黄科林; 王犇; 杨波; 张雪旺; 慕朝师; 孙果宋; 罗素娟

    2011-01-01

    [ Objective ] Starch modified polyurethane foam was prepared from cassava starch and sucrose and the effect of reaction conditions on product properties were studied. [ Method ] The structure and thermal stability of products were analyzed based on FT - IR, SEM, DSC and TG.Moreover,the soil burying method was used to investigate the degradability of products. [ Result] Cross - linking reaction was involved in the preparation process of products. The increasing of starch content caused the acceleration of degradation rate and the greater degree of degradation. [ Conclusion] The starch modified polyurethane foam,which has good thermal stability,low thermal conductivity and excellent biodegradability,which can be used as environmental friendly thermal insulation materials.%[目的]以木薯淀粉和蔗糖为起始原料制备淀粉改性聚氨酯泡沫塑料,研究反应条件对产品性能的影响.[方法]用FT-IR、SEM、DSC和TG分析产品的结构及热稳定性,通过土埋试验考察产品的降解性能.[结果]淀粉在聚氨酯的制备过程中参与交联反应,随着淀粉含量的增加,产品的降解速度有所加快,且降解的程度也越大.[结论]淀粉改性聚氨酯泡沫具有良好的热稳定性、较低的导热系数和优异的生物降解性能,可以作为环保的保温材料使用.

  8. Raman Spectroscopic Profile of Ethanol Fermentation in High Gravity Cassava Starch Brewing%浓醪乙醇发酵的单细胞拉曼光谱表征

    Institute of Scientific and Technical Information of China (English)

    李自达; 赖钧灼; 廖威; 刘军贤; 王桂文

    2012-01-01

    应用激光镊子拉曼光谱技术收集500 L发酵罐中木薯淀粉浓醪乙醇发酵过程底物、产物及酵母单细胞的拉曼光谱,以期从单细胞水平为乙醇发酵提供新的认识.结果显示:1)拉曼光谱可以实时监测浓醪乙醇发酵过程底物与产物的变化;2)酵母细胞胞内物质的变化存在类似于产物变化的前发酵期、主发酵期和后发酵期3个阶段,但出现的时间要比产物变化晚约4 h;3)为适应浓醪发酵环境,酵母细胞的生理状态和胞内物质在不断地进行调整,随着环境乙醇浓度的升高,酵母细胞在胞内累积蛋白质和脂类物质,蛋白质二级结构逐渐变为以无规则卷曲为主;4)发酵后期,酵母细胞在胞内累积大量的嘌呤类物质,但细胞间含量存在异质性.上述结果表明,单细胞拉曼光谱技术提供了一种研究微生物发酵的新方法,可从新的角度获知乙醇发酵过程酵母细胞内外的变化信息.%Raman spectroscopy is used to characterize the process of ethanol fermentation and look into the Saccharomyces cerevisiae cells at single-cell level. The ethanol fermentation using high-concentration cassava starch as feedstock is processed in a 500 L fermentor and the Raman spectra of substrate, product and individual yeast cell are acquired by using laser tweezers Raman spectroscopy (LTRS). Major results are as follows: 1) Raman spectroscopy can monitor the dynamic changes of substrate and product during the ethanol fermentation; 2) the changes of intracellular components of yeast cells exhibit three stages, I. E., primary fermentation, main fermentation and later fermentation, which are similar to those of products, but there is a delay of about 4 hi 3) yeast cells amend its physiological state and intracellular compounds to adapt to the high osmotic stress at the initial stage and the high ethanol concentration at the later stage of fermentation. Random coiling dominates the secondary structure of

  9. Effect of plasticizer type and concentration on physical properties of biodegradable films based on sugar palm (arenga pinnata) starch for food packaging.

    Science.gov (United States)

    Sanyang, M L; Sapuan, S M; Jawaid, M; Ishak, M R; Sahari, J

    2016-01-01

    In this study, sugar palm starch (SPS) films were developed using glycerol (G), sorbitol (S) or their combination (GS) as plasticizers at the ratio of 15, 30 and 45 (wt)% using casting technique. The addition of plasticizers to SPS film-forming solutions helped to overcome the brittle and fragile nature of unplasticized SPS films. Increased plasticizer concentration resulted to an increase in film thickness, moisture content and solubility. On the contrary, density and water absorption of plasticized films decreased with increasing plasticizer concentration. Raising the plasticizer content from 15 to 45 % showed less effect on the moisture content and water absorption of S-plasticized films. Films containing glycerol and glycerol-sorbitol plasticizer (G, and GS) demonstrated higher moisture content, solubility and water absorption capacity compared to S-plasticized films. The results obtained in this study showed that plasticizer type and concentration significantly improves film properties and enhances their suitability for food packaging applications.

  10. Cassava root membrane proteome reveals activities during storage root maturation.

    Science.gov (United States)

    Naconsie, Maliwan; Lertpanyasampatha, Manassawe; Viboonjun, Unchera; Netrphan, Supatcharee; Kuwano, Masayoshi; Ogasawara, Naotake; Narangajavana, Jarunya

    2016-01-01

    Cassava (Manihot esculenta Crantz) is one of the most important crops of Thailand. Its storage roots are used as food, feed, starch production, and be the important source for biofuel and biodegradable plastic production. Despite the importance of cassava storage roots, little is known about the mechanisms involved in their formation. This present study has focused on comparison of the expression profiles of cassava root proteome at various developmental stages using two-dimensional gel electrophoresis and LC-MS/MS. Based on an anatomical study using Toluidine Blue, the secondary growth was confirmed to be essential during the development of cassava storage root. To investigate biochemical processes occurring during storage root maturation, soluble and membrane proteins were isolated from storage roots harvested from 3-, 6-, 9-, and 12-month-old cassava plants. The proteins with differential expression pattern were analysed and identified to be associated with 8 functional groups: protein folding and degradation, energy, metabolism, secondary metabolism, stress response, transport facilitation, cytoskeleton, and unclassified function. The expression profiling of membrane proteins revealed the proteins involved in protein folding and degradation, energy, and cell structure were highly expressed during early stages of development. Integration of these data along with the information available in genome and transcriptome databases is critical to expand knowledge obtained solely from the field of proteomics. Possible role of identified proteins were discussed in relation with the activities during storage root maturation in cassava.

  11. Water barrier properties of starch-clay nanocomposite films Propriedades de barreira à água de filmes de nanocompósitos de amido e argila

    Directory of Open Access Journals (Sweden)

    Aníbal Marcelo Slavutsky

    2012-09-01

    Full Text Available The functional properties of corn starch based films were improved by incorporating nanoclay (Montmorillonite. Nanoclay was incorporated in the polymer matrix using two different methodologies and the films were formed by casting. The effect of film preparation methodology and of the nanoclay concentration on the physicochemical properties of the films was studied. Depending on film preparation method used, intercalated or exfoliated nanocomposite films were obtained. The FTIR spectra showed a strong interaction between the montmorillonite and the starch molecules. Opacity was dependent on the nanoclay dispersion method used. Water vapor solubility and permeability decreased with increasing montmorillonite content and were affected by the dispersion method. Water diffusion was only dependent on the nanoclay content due to the increase in tortuosity of the diffusion path, caused by the nanoparticles. The results showed that the incorporation of 5% of montmorillonite using an adequate dispersion method, improved the water resistance and barrier properties of corn starch based films. Nanoparticles reduced the damage caused to the properties of these hydrophilic films by the increase in moisture content.As propriedades funcionais de filmes à base de amido de milho foram melhoradas pela incorporação de nanoargila (montmorilonita. Nanoargila foi incorporada na matriz polimérica por meio de duas metodologias diferentes e os filmes foram produzidos por casting. Os efeitos da metodologia de preparação e da concentração de nanoargila nas propriedades físico-químicas dos filmes foram estudados. Conforme os métodos de elaboração, filmes intercalados e esfoliados de nanocompósitos foram obtidos. Os espectros FTIR mostraram uma forte interação entre a argila montmorilonita e as moléculas de amido. A opacidade foi dependente do método utilizado para a dispersão da nanoargila. A solubilidade e a permeabilidade ao vapor de água diminu

  12. Starch films: production, properties and potential of utilization / Filmes de amido: produção, propriedades e potencial de utilização

    Directory of Open Access Journals (Sweden)

    Fábio Yamashita

    2010-04-01

    Full Text Available There is an increasing interest in the utilization of renewable resources for the production of food packaging. Among the biopolymers, starches from several sources have been considered as one of the most promising material for this purpose, and the reasons for this are that starches are biodegradable, are inexpensive and available in the worldwide. This work presents a bibliography review about biodegradable starch films characterization and potential of utilization. Discusses the starch films mechanical and barrier properties, the cristallinity and the effects of the use of plasticizers over these properties. The discussed informations indicate that exist great possibilities for these materials in food packaging, which depend on the production of more stable materials and the development of production technology in industrial scale.O interesse no emprego de matérias-primas provenientes de recursos renováveis para a produção de embalagens de alimentos vem crescendo. Dentre os biopolímeros mais promissores para este fim estão os amidos de diversas fontes botânicas, que são biodegradáveis, têm custo baixo e estão disponíveis em todo o mundo. Diante disto, este trabalho apresenta uma revisão bibliográfica sobre a caracterização e o potencial de utilização de filmes biodegradáveis a base de amido. Discute as propriedades mecânicas, de barreira e a cristalinidade dos filmes de amido e o efeito do uso de plastificantes sobre estas propriedades. As informações disponibilizadas mostram que existem grandes possibilidades de utilização destes materiais como embalagens de alimentos que, no entanto, dependem da produção de materiais mais estáveis às condições de armazenamento e do desenvolvimento de tecnologia de produção em escala industrial.

  13. Production of ethanol from cassava pulp via fermentation with a surface-engineered yeast strain displaying glucoamylase

    Energy Technology Data Exchange (ETDEWEB)

    Kosugi, Akihiko; Murata, Yoshinori; Arai, Takamitsu; Mori, Yutaka [Post-harvest Science and Technology Division, Japan International Research Center for Agricultural Sciences (JIRCAS), 1-1 Ohwashi, Tsukuba, Ibaraki 305-8686 (Japan); Kondo, Akihiko [Department of Chemical Science and Engineering, Faculty of Engineering, Kobe University, Nada-ku, Kobe, 657-8501 (Japan); Ueda, Mitsuyoshi [Department of Applied Biochemistry, Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502 (Japan); Vaithanomsat, Pilanee; Thanapase, Warunee [Nanotechnology and Biotechnology Division, Kasetsart Agricultural and Agro-Industrial Product Improvement Institute (KAPI), Kasetsart University, 50 Chatuchak, Ladyao, Bangkok 10900 (Thailand)

    2009-05-15

    Cassava (Manihot esculenta Crantz) pulp, produced in large amounts as a by-product of starch manufacturing, is a major biomass resource in Southeast Asian countries. It contains abundant starch (approximately 60%) and cellulose fiber (approximately 20%). To effectively utilize the cassava pulp, an attempt was made to convert its components to ethanol using a sake-brewing yeast displaying glucoamylase on the cell surface. Saccharomyces cerevisiae Kyokai no. 7 (strain K7) displaying Rhizopus oryzae glucoamylase, designated strain K7G, was constructed using the C-terminal-half region of {alpha}-agglutinin. A sample of cassava pulp was pretreated with a hydrothermal reaction (140 C for 1 h), followed by treatment with a Trichoderma reesei cellulase to hydrolyze the cellulose in the sample. The K7G strain fermented starch and glucose in pretreated samples without addition of amylolytic enzymes, and produced ethanol in 91% and 80% of theoretical yield from 5% and 10% cassava pulp, respectively. (author)

  14. Preparation of mechanically activated starch acetate of ester-film material for carbamide controlled release and its film performance%尿素缓释膜材料--机械活化醋酸酯淀粉的制备及其膜性能

    Institute of Scientific and Technical Information of China (English)

    陈渊; 杨家添; 韦庆敏; 何军; 黄祖强; 欧诗德; 张秀姣

    2014-01-01

    In order to improve the properties of starch-based films for carbamide controlled release, the mechanically ac-tivated starch acetate (MASA) was synthesized from mechanically activated cassava starch (MAS). The biodegradable mechani-cally activated starch acetate polyvinyl alcohol(MASA/PVA) films were produced. Fourier transform infrared spectrogram (FT-IR), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC), the microstructure, particle shape and thermal property of MASA were studied. And the film performances were compared with those made of starch acetate (SA) with variacs degrees of substitution(DS). The results revealed that the microstructure and particle shape changed greatly and thermal property of MASA increased. The properties of MASA/PVA were better than those of SA/PVA. The tensile strength of the MA-SA/PVA with MASA ( DS = 0. 2 ) was 3. 23 MPa, the breaking elongation was 206. 68% before soaking in water, the absorption of water was 115. 96% after 24 h, and the rate of biodegradation was 36. 46% in the soil after 20 d. The to-tal urea stripping rate of MASA /PVA coated urea reached 45. 69% after 9 times leaching, 18. 12 percent and 51. 49 per-cent lower than urea and coated that with SA/PVA, respec-tively. Coating film made of MASA/PVA had remarkable controlling effects on urea nitrogen release.%为了有效提高淀粉基质尿素缓释膜的性能,对机械活化1.0 h的木薯淀粉( MAS)进行酯化改性,制备了机械活化醋酸酯淀粉(MASA)、机械活化醋酸酯淀粉/聚乙烯醇的生物降解塑料膜(MASA/PVA)及MASA/PVA包膜尿素。用傅立叶红外光谱仪(FTIR)、扫描电镜(SEM)、差示扫描量热仪(DSC)分别对MASA的结构、形貌、热稳定性等进行测试,并与用不同取代度制备的原木薯醋酸酯淀粉/聚乙烯醇生物降解塑料膜( SA/PVA)进行比较。结果表明,机械活化淀粉经酯化改性后,结构和形貌都有很大的改变,热性能提高;MASA/PVA的性

  15. Cassava as a food.

    Science.gov (United States)

    Okezie, B O; Kosikowski, F V

    1982-01-01

    This review has attempted to examine information pertaining to the role of cassava (Manihot esculenta) as a major food source for a large part of the world population, particularly the countries of South America, Africa, and Asia, where it is primarily a major source of energy for 300 to 500 million people. Its cultivation, usually on small farms with little technology, is estimated to cover on an annual basis about 11 million hectares providing about 105 million tons, more than half of which is consumed by humans. The importance of cassava as an energy source can be seen by its growing demand in the European economic community countries where it forms up to 60% of the balanced diets for swine. Cassava is one of the crops that converts the greatest amount of solar energy into soluble carbohydrates per unit of area, thus 1 kg of moisture-free cassava meal may yield up to about 3750 kcal which would mean that a yearly production of 15 tons of cassava meal per hectare would yield some 56 million kcal. The major limitations of cassava as food appear to be its poor protein content and quality and the rapid post harvest deterioration of its roots which usually prevents their storage in the fresh state for more than a few days. However, in addition to its use for culinary purposes, cassava finds application in industrial products such as an adhesive for laundry purposes, for manufacturing paper, alcohol, butanol, dextrin, adhesive tape, textile sizing, and glue.

  16. Direct ethanol production from cassava pulp using a surface-engineered yeast strain co-displaying two amylases, two cellulases, and {beta}-glucosidase

    Energy Technology Data Exchange (ETDEWEB)

    Apiwatanapiwat, Waraporn; Rugthaworn, Prapassorn [Japan International Research Center for Agricultural Sciences (JIRCAS), Tsukuba, Ibaraki (Japan). Post-Harvest Science and Technology Div.; Kasetsart Univ., Bangkok (Thailand). Nanotechnology and Biotechnology Div.; Murata, Yoshinori; Kosugi, Akihiko; Arai, Takamitsu; Mori, Yutaka [Japan International Research Center for Agricultural Sciences (JIRCAS), Tsukuba, Ibaraki (Japan). Post-Harvest Science and Technology Div.; Yamada, Ryosuke; Kondo, Akihiko [Kobe Univ. (Japan). Dept. of Chemical Science and Engineering

    2011-04-15

    In order to develop a method for producing fuel ethanol from cassava pulp using cell surface engineering (arming) technology, an arming yeast co-displaying {alpha}-amylase ({alpha}-AM), glucoamylase, endoglucanase, cellobiohydrase, and {beta}-glucosidase on the surface of the yeast cells was constructed. The novel yeast strain, possessing the activities of all enzymes, was able to produce ethanol directly from soluble starch, barley {beta}-glucan, and acid-treated Avicel. Cassava is a major crop in Southeast Asia and used mainly for starch production. In the starch manufacturing process, large amounts of solid wastes, called cassava pulp, are produced. The major components of cassava pulp are starch (approximately 60%) and cellulose fiber (approximately 30%). We attempted simultaneous saccharification and ethanol fermentation of cassava pulp with this arming yeast. During fermentation, ethanol concentration increased as the starch and cellulose fiber substrates contained in the cassava pulp decreased. The results clearly showed that the arming yeast was able to produce ethanol directly from cassava pulp without addition of any hydrolytic enzymes. (orig.)

  17. Physicochemical properties of maca starch.

    Science.gov (United States)

    Zhang, Ling; Li, Guantian; Wang, Sunan; Yao, Weirong; Zhu, Fan

    2017-03-01

    Maca (Lepidium meyenii Walpers) is gaining research attention due to its unique bioactive properties. Starch is a major component of maca roots, thus representing a novel starch source. In this study, the properties of three maca starches (yellow, purple and black) were compared with commercially maize, cassava, and potato starches. The starch granule sizes ranged from 9.0 to 9.6μm, and the granules were irregularly oval. All the maca starches presented B-type X-ray diffraction patterns, with the relative degree of crystallinity ranging from 22.2 to 24.3%. The apparent amylose contents ranged from 21.0 to 21.3%. The onset gelatinization temperatures ranged from 47.1 to 47.5°C as indicated by differential scanning calorimetry. Significant differences were observed in the pasting properties and textural parameters among all of the studied starches. These characteristics suggest the utility of native maca starch in products subjected to low temperatures during food processing and other industrial applications.

  18. Effect of silver nanoparticles' generation routes on the morphology, oxygen, and water transport properties of starch nanocomposite films

    Energy Technology Data Exchange (ETDEWEB)

    Cheviron, Perrine; Gouanvé, Fabrice, E-mail: fabrice.gouanve@univ-lyon1.fr; Espuche, Eliane, E-mail: eliane.espuche@univ-lyon1.fr [Université de Lyon (France)

    2015-09-15

    A strategy involving the preparation of silver nanoparticles in a biodegradable polymer stemming from an ex situ or an in situ method using a green chemistry process is reported. The influence of the reducing agent concentration and the silver nanoparticles' generation route were investigated on the structure, the morphology, and the properties of the nanocomposite films. Two distinct silver nanoparticle populations in size were highlighted from the ex situ route (diameter around 5 nm for the first one and from 20 to 50 nm for the second one), whereas one population was highlighted from the in situ route (around 10 nm). No modification on the crystalline structure of the starch matrix was observed in presence of silver. Crystalline silver nanoparticles were obtained only from the in situ generation route. The decrease of the water sorption and the improvement of water and oxygen barrier properties were found to be not dependent on the reducing agent concentration but mainly on the crystalline structure of the silver nanoparticles associated to the presence of strong interface between the silver nanoparticles and the starch polymer matrix.

  19. Sugarcane starch: quantitative determination and characterization

    Directory of Open Access Journals (Sweden)

    Joelise de Alencar Figueira

    2011-09-01

    Full Text Available Starch is found in sugarcane as a storage polysaccharide. Starch concentrations vary widely depending on the country, variety, developmental stage, and growth conditions. The purpose of this study was to determine the starch content in different varieties of sugarcane, between May and November 2007, and some characteristics of sugarcane starch such as structure and granules size; gelatinization temperature; starch solution filterability; and susceptibility to glucoamylase, pullulanase, and commercial bacterial and fungal α-amylase enzymes. Susceptibility to debranching amylolytic isoamylase enzyme from Flavobacterium sp. was also tested. Sugarcane starch had spherical shape with a diameter of 1-3 µm. Sugarcane starch formed complexes with iodine, which showed greater absorption in the range of 540 to 620 nm. Sugarcane starch showed higher susceptibility to glucoamylase compared to that of waxy maize, cassava, and potato starch. Sugarcane starch also showed susceptibility to debranching amylolytic pullulanases similar to that of waxy rice starch. It also showed susceptibility to α-amylase from Bacillus subtilis, Bacillus licheniformis, and Aspergillus oryzae similar to that of the other tested starches producing glucose, maltose, maltotriose, maltotetraose, maltopentose and limit α- dextrin.

  20. Effect of starch types on properties of biodegradable polymer based on thermoplastic starch process by injection molding technique

    Directory of Open Access Journals (Sweden)

    Yossathorn Tanetrungroj

    2015-04-01

    Full Text Available In this study effects of different starch types on the properties of biodegradable polymer based on thermoplastic starch (TPS were investigated. Different types of starch containing different contents of amylose and amylopectin were used, i.e. cassava starch, mungbean starch, and arrowroot starch. The TPS polymers were compounded and shaped using an internal mixer and an injection molding machine, respectively. It was found that the amount of amylose and amylopectin contents on native starch influence the properties of the TPS polymer. A high amylose starch of TPMS led to higher strength, hardness, degree of crystallization than the high amylopectin starch of TPCS. In addition, function group analysis by Fourier transforms infrared spectrophotometer, water absorption, and biodegradation by soil burial test were also examined.

  1. Direct fermentation of raw starch using a Kluyveromyces marxianus strain that expresses glucoamylase and alpha-amylase to produce ethanol.

    Science.gov (United States)

    Wang, Rongliang; Wang, Dongmei; Gao, Xiaolian; Hong, Jiong

    2014-01-01

    Raw starch and raw cassava tuber powder were directly and efficiently fermented at elevated temperatures to produce ethanol using the thermotolerant yeast Kluyveromyces marxianus that expresses α-amylase from Aspergillus oryzae as well as α-amylase and glucoamylase from Debaryomyces occidentalis. Among the constructed K. marxianus strains, YRL 009 had the highest efficiency in direct starch fermentation. Raw starch from corn, potato, cassava, or wheat can be fermented at temperatures higher than 40°C. At the optimal fermentation temperature 42°C, YRL 009 produced 66.52 g/L ethanol from 200 g/L cassava starch, which was the highest production among the selected raw starches. This production increased to 79.75 g/L ethanol with a 78.3% theoretical yield (with all cassava starch were consumed) from raw cassava starch at higher initial cell densities. Fermentation was also carried out at 45 and 48°C. By using 200 g/L raw cassava starch, 137.11 and 87.71 g/L sugar were consumed with 55.36 and 32.16 g/L ethanol produced, respectively. Furthermore, this strain could directly ferment 200 g/L nonsterile raw cassava tuber powder (containing 178.52 g/L cassava starch) without additional nutritional supplements to produce 69.73 g/L ethanol by consuming 166.07 g/L sugar at 42°C. YRL 009, which has consolidated bioprocessing ability, is the best strain for fermenting starches at elevated temperatures that has been reported to date.

  2. FILMES BIODEGRADÁVEIS DE AMIDO DE MANDIOCA, PULULANA E CELULOSE BACTERIANA

    Directory of Open Access Journals (Sweden)

    Ana Claudia Sueiro

    Full Text Available The largest consumption of plastics in the world is referred to the synthetic polymers, which are not biodegradable and have a non-renewable source, generating a large environmental impact, especially in urban centers. As a result, in the last two decades several polymers obtained from renewable sources (biopolymers have been studied as potential raw materials for the production of new biodegradable materials with different applications. The objectives of this study were to produce biodegradable films based on cassava starch, pullulan and bacterial cellulose, and also to characterize these films according to their microstructure, barrier, thermal and mechanical properties. The addition of bacterial cellulose and pullulan to the starch films resulted in films with more homogeneous surfaces, and also decreased solubility and water vapor permeability, and increased elongation and thermal stability.

  3. Performance of polymeric films based thermoplastic starch and organophilic clay; Efeito da incorporacao de argila no desempenho de filmes de amido termoplastico/PEBD

    Energy Technology Data Exchange (ETDEWEB)

    Cipriano, P.B.; Costa, A.N.M.; Araujo, S.S.; Araujo, A.R.A.; Canedo, E.L.; Carvalho, L.H., E-mail: pamufcg@gmail.co [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Dept. de Engenharia de Materiais

    2010-07-01

    The aim of this work was the development and investigation of the properties of flat films of LDPE/corn thermoplastic starch (TPS). A bentonite clay (Argel) was organophilized and characterized by XRD. This clay (1%) in both pristine and organophilic forms was added to the matrix (LDPE) and to LDPE/TPS systems with TPS contents varying from 5-20% w/w. The films manufactured (LDPE, LDPE/Clay, LDPE/TPS, LDPE/TPS/Clay) were characterized. Results indicate that water vapor permeability is dependent and increases with TPS content which was attributed to the higher affinity of water by TPS. TPS and Clay addition to LDPE led to significant changes in film properties with respect to the neat LDPE. In general,tensile and perforation forces increased with clay and TPS contents; the strength of thermo sealed films lowered with natural clay addition and increased with TPS and organoclay incorporation and, in general, dynamic friction coefficient decrease with organoclay and TPS addition. Best overall properties were obtained for the systems containing the organoclay and optimal properties were achieved for the 5%TPS10 LDPE1% ANO system. (author)

  4. Biopolymeric antimicrobial films: study of the influence of hydroxypropyl methylcellulose, tapioca starch and glycerol contents on physical properties.

    Science.gov (United States)

    Espinel Villacrés, Ricardo A; Flores, Silvia K; Gerschenson, Lía N

    2014-03-01

    Mixture design methodology was applied to study the effect of different levels of tapioca starch (TS), hydroxypropyl methylcelullose (HPMC), and glycerol (Gly) on the physical properties of biopolymeric films supporting potassium sorbate (KS; 0.3% w/w) with the goal of contributing to the development of materials for preventing food surface contamination. Mechanical properties, water vapour permeability (WVP), solubility in water (S) and colour attributes were evaluated on the films. HPMC addition produced an increase of elastic modulus (Ec), stress at break (σb) and S. It also decreased the yellow index (YI) values and the strain at break (εb). The study was deepened using the formulation containing 2.67 g/100g of TS, 0.67 g/100g of HPMC, 1.67 g/100g Gly and 0.3g/100g KS, observing that it behaved as an effective antimicrobial barrier against Zygosaccharomyces bailii external contamination. Microstructural analysis allowed us to conclude that HPMC incorporation to a TS network decreased roughness of the films and it also increased permeability to oxygen (PO2).

  5. Cassava genome from a wild ancestor to cultivated varieties.

    Science.gov (United States)

    Wang, Wenquan; Feng, Binxiao; Xiao, Jingfa; Xia, Zhiqiang; Zhou, Xincheng; Li, Pinghua; Zhang, Weixiong; Wang, Ying; Møller, Birger Lindberg; Zhang, Peng; Luo, Ming-Cheng; Xiao, Gong; Liu, Jingxing; Yang, Jun; Chen, Songbi; Rabinowicz, Pablo D; Chen, Xin; Zhang, Hong-Bin; Ceballos, Henan; Lou, Qunfeng; Zou, Meiling; Carvalho, Luiz J C B; Zeng, Changying; Xia, Jing; Sun, Shixiang; Fu, Yuhua; Wang, Haiyan; Lu, Cheng; Ruan, Mengbin; Zhou, Shuigeng; Wu, Zhicheng; Liu, Hui; Kannangara, Rubini Maya; Jørgensen, Kirsten; Neale, Rebecca Louise; Bonde, Maya; Heinz, Nanna; Zhu, Wenli; Wang, Shujuan; Zhang, Yang; Pan, Kun; Wen, Mingfu; Ma, Ping-An; Li, Zhengxu; Hu, Meizhen; Liao, Wenbin; Hu, Wenbin; Zhang, Shengkui; Pei, Jinli; Guo, Anping; Guo, Jianchun; Zhang, Jiaming; Zhang, Zhengwen; Ye, Jianqiu; Ou, Wenjun; Ma, Yaqin; Liu, Xinyue; Tallon, Luke J; Galens, Kevin; Ott, Sandra; Huang, Jie; Xue, Jingjing; An, Feifei; Yao, Qingqun; Lu, Xiaojing; Fregene, Martin; López-Lavalle, L Augusto Becerra; Wu, Jiajie; You, Frank M; Chen, Meili; Hu, Songnian; Wu, Guojiang; Zhong, Silin; Ling, Peng; Chen, Yeyuan; Wang, Qinghuang; Liu, Guodao; Liu, Bin; Li, Kaimian; Peng, Ming

    2014-10-10

    Cassava is a major tropical food crop in the Euphorbiaceae family that has high carbohydrate production potential and adaptability to diverse environments. Here we present the draft genome sequences of a wild ancestor and a domesticated variety of cassava and comparative analyses with a partial inbred line. We identify 1,584 and 1,678 gene models specific to the wild and domesticated varieties, respectively, and discover high heterozygosity and millions of single-nucleotide variations. Our analyses reveal that genes involved in photosynthesis, starch accumulation and abiotic stresses have been positively selected, whereas those involved in cell wall biosynthesis and secondary metabolism, including cyanogenic glucoside formation, have been negatively selected in the cultivated varieties, reflecting the result of natural selection and domestication. Differences in microRNA genes and retrotransposon regulation could partly explain an increased carbon flux towards starch accumulation and reduced cyanogenic glucoside accumulation in domesticated cassava. These results may contribute to genetic improvement of cassava through better understanding of its biology.

  6. 可食性绿豆淀粉膜制作工艺的研究%Study on Processing Technology of Edible Mung Bean Starch Film

    Institute of Scientific and Technical Information of China (English)

    姬娜; 熊柳; 卜祥辉; 孙庆杰

    2012-01-01

    The effects of mung bean starch, glycerin content, CMC content, drying temperature and drying time on film characteristic were studied in this paper. The film properties were determined with thickness, tensile strength, elongation at break, and barrier of moisture. The results showed that mung bean starch, with 0.4 g glycerol per gram starch and 0.06 g CMC per gram starch, was the main part of film formation, which was dried at 80 ℃ for four hours. The tensile strength of mung bean starch film was 9. 51 Mpa, the elongation at break was 114. 55% , and the barrier of moisture was 240. 98 min/mm.%以绿豆淀粉为主要材料,甘油作为增塑剂,羧甲基纤维素(CMC)作为增强剂,以可食性膜厚度、抗拉强度、断裂延伸率、阻水性为指标,研究了甘油添加量、CMC添加量、干燥温度、干燥时间等因素对可食性淀粉膜性能的影响.结果表明以绿豆淀粉为成膜主体,配以0.4g/g淀粉的甘油和0.06g/g淀粉的CMC,在80℃烘干4h,得到淀粉膜的抗拉强度为9.51 MPa,延伸率为114.55%,水滴渗透时间(Ts)为240.98 min/mm.

  7. Elaboração de biscoitos de chocolate com substituição parcial da farinha de trigo por polvilho azedo e farinha de albedo de laranja Chocolate biscuits preparation with partial substitution of wheat flour by fermented cassava starch and orange albedo flour

    Directory of Open Access Journals (Sweden)

    Aline Alves Oliveira Santos

    2011-03-01

    Full Text Available Os consumidores estão cada vez mais exigentes e preocupados com a saúde e, por consequência, exigindo produtos naturais que deverão ser seguros e promover qualidade de vida. O presente trabalho teve o objetivo de desenvolver biscoitos com farinhas mistas de polvilho azedo e farinha de albedo de laranja, utilizando um planejamento fatorial 2³, com variáveis independentes: concentração de polvilho azedo, açúcar e farinha de albedo de laranja, e variáveis respostas: as características sensoriais: aparência, aroma, textura e sabor, além da impressão global, utilizando escala hedônica estruturada de nove pontos. Os biscoitos foram avaliados também quanto às características físico-químicas. As médias obtidas para as características sensoriais estiveram na faixa que vai de cinco (não gostei nem desgostei até sete (gostei moderadamente, não apresentando diferença significativa (P≤0,05 para todas as características sensoriais avaliadas. Dessa maneira, foi possível escolher a formulação ideal obtida de acordo com os parâmetros nutricionais, por não existir diferença sensorial significativa, que foi 35% de polvilho azedo, 100% de açúcar e 7,5% de farinha de albedo de laranja. No teste sensorial comparativo com os biscoitos comercial, padrão e otimizado, as características sensoriais aparência, sabor e textura apresentaram diferença significativa (P≤0,05. As características físico-químicas apresentaram resultados correspondentes aos padrões estabelecidos pela legislação brasileira, e o teor de fibra bruta do biscoito otimizado foi de 3,08%, assim, pode ser classificado como biscoito "fonte de fibras".The consumers are increasingly demanding and worried about health and, consequently, requiring natural products that should be safe and that promote life quality. The present research had the objective to develop biscuits with mixed flour of fermented cassava starch and orange albedo flour, using a 2³ factorial

  8. TEKNOLOGI MODIFIKASI TEPUNG KASAVA Modified Cassava Flour Technology

    Directory of Open Access Journals (Sweden)

    Haryadi Haryadi

    2012-05-01

    Full Text Available Cassava productivity is very potential to support food security. Processing of cassava into flour makes the food more durable, less voluminous and easier to handle, and flexible to cook. To extend the use of cassava flour, it is necessary to develop technology to produce quality cassava flour suitable for various food purposes. A certain flour finess is desired to free the starch granules and to allow the granule’s cooking characteristics to express significantly. Modification of cassava flour technology may involve physical, biological, chemical aspects, as well as combination of the aspects. ABSTRAK Potensi produksi kasava sangat besar untuk dimanfaatkan sebagai pendukung ketahanan pangan. Pengolahannya men­ jadi tepung memungkinkan lebih awet, lebih ringkas dan lebih mudah diangkut, serta lebih luwes untuk diolah. Untuk memperluas penggunaan tepung kasava, perlu pengembangan teknologi produksi tepung bermutu yang dapat diman­ faatkan dalam berbagai olahan makanan. Tepung dikehendaki pada kelembutan tertentu, sehingga granula-granula pati terlepas dari jaringan awalnya, dan selanjutnya ciri-ciri granula dalam pemasakan menjadi nyata. Modifikasi pembuatan tepung kasava dapat dilakukan secara fisik, biologis maupun kimiawi, ataupun gabungan dari aspek-aspek tersebut.

  9. Synthesis of Rosin Acid Starch Catalyzed by Lipase

    Directory of Open Access Journals (Sweden)

    Rihui Lin

    2014-01-01

    Full Text Available Rosin, an abundant raw material from pine trees, was used as a starting material directly for the synthesis of rosin acid starch. The esterification reaction was catalyzed by lipase (Novozym 435 under mild conditions. Based on single factor experimentation, the optimal esterification conditions were obtained as follows: rosin acid/anhydrous glucose unit in the molar ratio 2 : 1, reaction time 4 h at 45°C, and 15% of lipase dosage. The degree of substitution (DS reaches 0.098. Product from esterification of cassava starch with rosin acid was confirmed by FTIR spectroscopy and iodine coloration analysis. Scanning electron microscopy and X-ray diffraction analysis showed that the morphology and crystallinity of the cassava starch were largely destroyed. Thermogravimetric analysis indicated that thermal stability of rosin acid starch decreased compared with native starch.

  10. Structural characterization of Peruvian carrot (Arracacia xanthorrhiza) starch and the effect of annealing on its semicrystalline structure.

    Science.gov (United States)

    Rocha, Thais S; Cunha, Verena A G; Jane, Jay-Lin; Franco, Celia M L

    2011-04-27

    Structural characteristics of native and annealed Peruvian carrot (Arracacia xanthorrhiza) starches were determined and compared to those of cassava and potato starches. Peruvian carrot starch presented round and irregular shaped granules, low amylose content and B-type X-ray pattern. Amylopectin of this starch contained a large proportion of long (DP > 37) and short (DP 6-12) branched chains. These last ones may contribute to its low gelatinization temperature. After annealing, the gelatinization temperatures of all starches increased, but the ΔH and the crystallinity increased only in Peruvian carrot and potato starches. The annealing process promoted a higher exposure of Peruvian carrot amylose molecules, which were more quickly attacked by enzymes, whereas amylopectin molecules became more resistant to hydrolysis. Peruvian carrot starch had structural characteristics that differed from those of cassava and potato starches. Annealing affected the semicrystalline structure of this starch, enhancing its crystallinity, mainly due to a better interaction between amylopectin chains.

  11. Optimization of enzymatic hydrolysis of cassava to obtain fermentable sugars

    Institute of Scientific and Technical Information of China (English)

    Renata M. COLLARES; Luiza V. S. MIKLASEVICIUS; Mariana M. BASSACO; Nina P. G. SALAU; Marcio A. MAZUTTI; Dilson A. BISOGNIN; Lisiane M. TERRA

    2012-01-01

    This work evaluates the enzymatic hydrolysis of starch from cassava using pectinase,α-amylase,and amyloglucosidase.A central composite rotational design (CCRD) was carried out to evaluate the effects of amyloglucosidase,pectinase,reaction time,and solid to liquid ratio.All the experiments were carried out in a bioreactor with working volume of 2 L.Approximately 98% efficiency hydrolysis was obtained,resulting in a concentration of total reducing sugar released of 160 g/L.It was concluded that pectinase improved the hydrolysis of starch from cassava.Reaction time was found to be significant until 7 h of reaction.A solid to liquid ratio of 1.0 was considered suitable for hydrolysis of starch from cassava.Amyloglucosidase was a significant variable in the process:after its addition to the reaction media,a 30%-50% increase in the amount of total reducing sugar released was observed.At optimal conditions the maximum productivity obtained was 22.9 g/(L·h).

  12. Resistance to moist conditions of whey protein isolate and pea starch biodegradable films and low density polyethylene nondegradable films: a comparative study

    Science.gov (United States)

    Mehyar, G. F.; Bawab, A. Al

    2015-10-01

    Biodegradable packaging materials are degraded under the natural environmental conditions. Therefore using them could alleviate the problem of plastics accumulation in nature. For effective replacement of plastics, with biodegradable materials, biodegradable packages should keep their properties under the high relative humidity (RH) conditions. Therefore the objectives of the study were to develop biodegradable packaging material based on whey protein isolate (WPI) and pea starch (PS). To study their mechanical, oxygen barrier and solubility properties under different RHs compared with those of low density polyethylene (LDPE), the most used plastic in packaging. Films of WPI and PS were prepared separately and conditioned at different RH (30-90%) then their properties were studied. At low RHs ( 40% RH. Oxygen permeability of WPI and LDPE did not adversely affected by increasing RH to 65%. Furthermore, WPI and LDPE films had lower degree of hydration at 50% and 90% RH and total soluble matter than PS films. These results suggest that WPI could be successfully replacing LDPE in packaging of moist products.

  13. Effect of adsorption of an inhibitory factor on raw starch hydrolysis by glucoamylase.

    Science.gov (United States)

    Towprayoon, S; Fujio, Y; Ueda, S

    1990-12-01

    An inhibitory factor (IF) produced byAspergillus niger strain 19, and which inhibits the action of glucoamylase on starch, has the ability to be tightly adsorbed on to various raw starches, though the amount differs from starch to starch. Based on the hydrolysis of the IF-starch complex by glucoamylase, the inhibitions per unit IF adsorbed are similar for some varieties of starch. The effectiveness ratio of IF (% hydrolysis inhibition per % IF adsorbed on raw starch) for corn, sweet potato, waxy rice and waxy corn starches are 1.1, 1.0, 0.85 and 0.96, respectively. These results support the hypothesis that both glucoamylase and IF are adsorbed on to a common binding site on raw starch. However, the effectiveness ratio of IF for cassava and wheat starches are 0.71 and 1.65, respectively, which differ significantly from other varieties of starch.

  14. Effect of Starch Sources on the Release Rates of Herbicides Encapsulated

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The effects of starch sources on the behaviors of starch matrices and on the rates of herbicides released from the matrices were studied for slow release. The starches considered include native corn starch, wheat starch, potato starch and cassava starch. The matrices were prepared through encapsulating 2,4-dichlorophenoxyacetic or 2,4,5-trichlorophenoxyacetic acids as model herbicides with hot-gelatinized starch pastes. The encapsulation was evaluated in terms of herbicide content, swellability, encapsulation efficiency, and release rate. The results show that starch sources play an important role on the matrix behaviors and on release rates. The rate of 2,4-D released follows the order: wheat starch < potato starch < corn starch < cassava starch. And for the rate of 2,4,5-T, this order is nearly the same only with an exception that the late two kinds of starch are similar. It is also demonstrated that herbicides with different water solubility show different release rates, no matter what type of starch is used as the matrices.

  15. MICROMORPHOLOGICAL STUDIES OF STARCH GRANULES IN SELECTED PROCESSED INDIGENOUS FLOUR OF SOUTH WESTERN NIGERIA

    Directory of Open Access Journals (Sweden)

    Adeniyi A. JAYEOLA

    2013-06-01

    Full Text Available Starch granules of yam stem tubers, plantain fruits and cassava root tubers were studied using the light microscope and then compared. Yam and plantain, both monocotyledons, had morphologically similar granules between locations, being mostly oval in shape while the granules of cassava, a dicot, were predominantly globular but varied between locations. Differences in processing methods between locations might be responsible for the observed variation in cassava granules. There is a suggestion that starch granule morphology might follow lineages in a broad sense. The unique micromorphology of cassava starch granule could make it easily detectable when adulterated, substituted or contaminated with yam or plantain granules and this could provide a cost effective clue in forensic determination.

  16. Corrosion of Steels in Steel Reinforced Concrete in Cassava Juice

    Science.gov (United States)

    Oluwadare, G. O.; Agbaje, O.

    The corrosion of two types of construction steels, ST60Mn and RST37-2♦, in a low cyanide concentration environment (cassava juice) and embedded in concrete had been studied. The ST60 Mn was found to be more corrosion resistant in both ordinary water and the cassava juice environment. The cyanide in cassava juice does not attack the steel but it provides an environment of lower pH around the steel in the concrete which leads to breakdown of the passivating film provided by hydroxyl ions from cement. Other factors such as the curing time of the concrete also affect the corrosion rates of the steel in the concrete. The corrosion rate of the steel directly exposed to cassava juice i.e., steel not embedded in concrete is about twice that in concrete. Long exposure of concrete structure to cassava processing effluent might result in deterioration of such structures. Careful attention should therefore be paid to disposal of cassava processing effluents, especially in a country like Nigeria where such processing is now on the increase.

  17. Starch poisoning

    Science.gov (United States)

    Cooking starch poisoning; Laundry starch poisoning ... Cooking and laundry starch are both made from vegetable products, most commonly: Corn Potatoes Rice Wheat Both are usually considered nonpoisonous (nontoxic), but ...

  18. Propriedades de barreira e solubilidade de filmes de amido de ervilha associado com goma xantana e glicerol Barrier properties of films of pea starch associated with xanthan gum and glycerol

    Directory of Open Access Journals (Sweden)

    Manoel D. da Matta Jr

    2011-01-01

    Full Text Available O objetivo do trabalho foi avaliar as propriedades de barreira e a solubilidade de biofilmes obtidos a partir de amido de ervilha de alto teor de amilose em associação à goma xantana e glicerol. Soluções filmogênicas (SF com diferentes teores de amido de ervilha (3, 4 e 5%, goma xantana (0, 0,05 e 0,1% e glicerol (proporção glicerol-amido de 1:5 P/P foram estudadas. As SF foram obtidas por ebulição (5 minutos, seguida de autoclavagem por 1 hora a 120 ºC e os filmes foram preparados por casting. O aumento da concentração de amido e de glicerol na composição causou aumento da espessura e da solubilidade dos filmes em água. O plastificante gerou ainda elevação dos coeficientes de permeabilidade ao vapor d'água e ao oxigênio. O aumento da concentração da goma xantana não interferiu nas propriedades estudadas. Os biofilmes obtidos a partir de amido de ervilha verde, associado ou não à goma xantana e glicerol, se comparados com filmes de amido de ervilha amarelas e outras fontes de amido, apresentaram boa barreira ao oxigênio e ao vapor d'água e baixa solubilidade em água.The aim of this work was to evaluate the barrier properties and solubility of biofilms made from wrinkled pea starch with high amylose content in association with xanthan gum and glycerol. Filmogenic solution (FS with different levels of pea starch (3, 4 and 5%, xanthan gum (0, 0.05 and 0.1% and glycerol (glycerol-starch 1:5 W/W were tested. FS was obtained by boiling (5 minutes, autoclaving for 1 hour at 120 ºC and the films were prepared by casting. The increased concentration of starch and glycerol in the composition caused increases in thickness of the films and in their solubility in water. The plasticizer also generated higher coefficients of water vapor and oxygen permeabilities to water vapor and to oxygen. The increasing concentration of xanthan gum did not interfere in the properties studied. Biofilms produced with wrinkled pea starch, with or

  19. Application of thermophilic enzymes and water jet system to cassava pulp.

    Science.gov (United States)

    Chaikaew, Siriporn; Maeno, Yuka; Visessanguan, Wonnop; Ogura, Kota; Sugino, Gaku; Lee, Seung-Hwan; Ishikawa, Kazuhiko

    2012-12-01

    Co-production of fermentable sugars and nanofibrillated cellulose from cassava pulp was achieved by the combination of thermophilic enzymes (endoglucanase, β-glucosidase, and α-amylase) and a new atomization system (Star Burst System; SBS), which employs opposing water jets. The SBS represents a key technology for providing cellulose nanofibers and improving the enzymatic saccharification of cassava pulp. Depending on the enzymes used, the production of glucose from cassava pulp treated with the SBS was 1.2- to 2.5-fold higher than that from pulp not treated with the SBS. Nanofibrillated cellulose with the gel-like property in suspension was produced (yield was over 90%) by α-amylase treatment, which completely released trapped starch granules from the fibrous cell wall structure of cassava pulp pretreated with the SBS. The SBS provides an environmentally low-impact pretreatment system for processing biomass material into value-added products.

  20. [Application of ICP-MS to detection of mineral elements and heavy metals in Cassava's byproducts].

    Science.gov (United States)

    Tao, Hai-Teng; Zhang, Chun-Jiang; Chen, Xiao-Ming; Lüi, Fei-Jie; Tai, Jian-Xiang; Li, Kai-Mian

    2009-07-01

    Cassava is a main cultivated tropical crop in China, its rich starch roots are often used to produce fuel ethanol in recent years, so it's a kind of hot biomass energy crops. But cassava's byproducts such as leaves, stems and peels are regarded as waste, and are not fully utilized. Cassava's byproducts contain many nutrients, and can be used to process high value food products. The contents of mineral elements and heavy metals in cassava's byproducts were studied by ICP-MS. The results showed that cassava's byproducts contained many elements necessary to human health, the sequence of macroelements was K>Ca>P> Mg>S>Mn>Zn>Na>Fe>B>Cu, particularly, the contents of Fe, Mn, Zn and B ranged from 10 to 800 microg x g(-1) (DW), while the contents of microelements including Mo, Co, Se and Ge ranged from 0.01 to 0.2 microg x g(-1) (DW), which are important to human health. Besides macroelements and microelements, the contents of heavy metals (As, Cr, Pb and Hg) were also important to identify the quality of farm products, and the results showed that cassava's byproducts contained little heavy metals except Pb (2.19 microg x g(-1) (DW) in stalk peels). All the data showed that cassava's byproducts accorded with the national hygiene standards.

  1. Cassava (Manihot esculenta Crantz).

    Science.gov (United States)

    Bull, Simon E

    2015-01-01

    Genetic transformation of plants is an indispensable technique used for fundamental research and crop improvement. Recent advances in cassava (Manihot esculenta Crantz) transformation have facilitated the effective generation of stably transformed cassava plants with favorable traits. Agrobacterium-mediated transformation of friable, embryogenic callus has evolved to become the most widely used approach and has been adopted by research laboratories in Africa. This procedure utilizes axillary meristem tissue (buds) to produce primary and secondary somatic embryos and subsequently friable, embryogenic callus. Agrobacterium harboring a binary expression cassette is used to transform this tissue, which is regenerated via cotyledons and shoot organogenesis to produce rooted in vitro plantlets. This chapter details each step of the procedure using the model cultivar 60444 and provides supplementary notes to successfully produce transgenic cassava.

  2. Characterization of chestnut (Castanea sativa, mill) starch for industrial utilization

    OpenAIRE

    2001-01-01

    Studies were conducted to characterize the chestnut and its starch. Chemical composition of the chestnuts showed high level of starch. Moisture level in the raw nuts was around 50g/100g in wet basis and starch content, around 80g/100g in dry basis; other nut flour components were protein (5.58 g/100g), lipid (5.39 g/100g), crude fiber (2.34 g/100g) and ash (2.14 g/100g). Starch fraction was chemically characterized in order to identify the granule quality as compared with those of cassava and...

  3. Cassava For Space Diet

    Science.gov (United States)

    Katayama, Naomi; Yamashita, Masamichi; Njemanze, Philip; Nweke, Felix; Mitsuhashi, Jun; Hachiya, Natumi; Miyashita, Sachiko; Hotta, Atuko

    Space agriculture is an advanced life support enginnering concept based on biological and ecological system ot drive the materials recycle loop and create pleasant life environment on distant planetary bodies. Choice of space diet is one of primary decision required ot be made at designing space agriculture. We propose cassava, Manihot esculenta and, for one major composition of space food materials, and evaluate its value and feasibility of farming and processing it for space diet. Criteria to select space crop species could be stated as follows. 1) Fill th enutritional requirements. There is no perfect food material to meet this requirements without making a combination with others. A set of food materials which are adopted inthe space recipe shall fit to the nutritional requirement. 2) Space food is not just for maintaining physiological activities of human, but an element of human culture. We shall consider joy of dining in space life. In this context, space foos or recipe should be accepted by future astronauts. Food culture is diverse in the world, and has close relatioship to each cultural background. Cassava root tuber is a material to supply mainly energy in the form of carbohydrate, same as cereals and other tuber crops. Cassava leaf is rich in protein high as 5.1 percents about ten times higher content than its tuber. In the food culture in Africa, cassava is a major component. Cassava root tuber in most of its strain contains cyanide, it should be removed during preparation for cooking. However certain strain are less in this cyanogenic compound, and genetically modified cassava can also aboid this problem safely.

  4. Effect of Starch Sources and Protein Content on Extruded Aquaculture Feed Containing DDGS

    Science.gov (United States)

    A 3x3 completely randomized design was used to investigate the extrusion cooking and product characteristics of DDGS, protein levels, and various starch sources in a laboratory scale single screw extruder. Cassava, corn, and potato starches with varying levels of DDGS (20, 30, and 40% wb) were extru...

  5. Use of biomass energy. Saccharification of raw starch and ethanol fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Ueda, S.

    1982-01-01

    Raw starch was saccharified under acidic condition of pH 3.5 using black-koji amylase, and the resultant saccharidies were fermented to give ethanol in succession. White polished rice flour was fermented at 30 degrees C during the period of 7 to 10 days to give ethanol. Semi-continuous ethanol fermentation was carried out using corn starch and cassava starch. Batch ethanol fermentation was also carried out using cassava or sweet potato. Sweet potato was fermented using Rhizopus gluco-amylase. 11 references.

  6. Effect of Cassava Starch Anaerobic Fermentation Liquid on Pumpkin Growth, Yield and Fruit Quality%木薯淀粉厌氧发酵液对南瓜生长发育、产量及果实品质的影响

    Institute of Scientific and Technical Information of China (English)

    邓英毅; 陈群; 黄影花; 雷雪娇; 禤为翔; 韦仕飞; 韦思羽; 韦民政; 叶亦心; 郑虚; 张艺超; 莫干辉; 李韦柳; 张新宇; 王向导

    2016-01-01

    In order to ascertain the new resource utilizating way of cassava starch waste for environmental protection,this paper studied the effect of cassava starch anaerobic fermentation liquid (CSAFL)on pumpkin growth,yield and fruit quality,taking ‘Mibennangua’ as experimental material.The results showed that applying CSAFL could significantly promote the vegetative and reproductive growth,increase pumpkin yield and improve its fruit quality. Using CSAFL could also remarkably promote the growth of pumpkin main stem and leaves,increase leaf chlorophyll content. Besides,its fruit setting number per single plant,single fruit weight and yield were higher than that of the contrast by over 50%. Its fruit size,fruit shape index,contents of soluble solid,soluble sugar,soluble protein,starch and VC were significantly or very significantly increased than that of the contrast.Therefore,CSAFL can be used as additional fertilizer in pumpkin production,so as to realize the dual purposes of turning waste into wealth,and improving pumpkin yield and quality.%为了探明木薯淀粉废液的环保资源化利用新路子,以蜜本南瓜为试验材料,开展了木薯淀粉厌氧发酵液对南瓜生长发育、产量和果实品质的影响研究。结果表明,施用木薯淀粉厌氧发酵液能显著促进南瓜植株的营养生长和生殖生长,提高产量并改善果实的品质。施用木薯淀粉厌氧发酵液能显著促进植株主蔓和叶片的生长,增加叶片叶绿素含量,单株结瓜数、单瓜质量和产量均比常规施肥对照提高50%以上,其果实大小、果形指数、可溶性固形物、可溶性糖、可溶性蛋白、淀粉含量和VC含量也比对照显著或极显著提高。木薯淀粉厌氧发酵液可作为追肥在南瓜生产中应用,达到变废为宝、提高南瓜产量和品质的双重目的。

  7. An ordered EST catalogue and gene expression profiles of cassava (Manihot esculenta) at key growth stages.

    Science.gov (United States)

    Li, You-Zhi; Pan, Ying-Hua; Sun, Chang-Bin; Dong, Hai-Tao; Luo, Xing-Lu; Wang, Zhi-Qiang; Tang, Ji-Liang; Chen, Baoshan

    2010-12-01

    A cDNA library was constructed from the root tissues of cassava variety Huanan 124 at the root bulking stage. A total of 9,600 cDNA clones from the library were sequenced with single-pass from the 5'-terminus to establish a catalogue of expressed sequence tags (ESTs). Assembly of the resulting EST sequences resulted in 2,878 putative unigenes. Blastn analysis showed that 62.6% of the unigenes matched with known cassava ESTs and the rest had no 'hits' against the cassava database in the integrative PlantGDB database. Blastx analysis showed that 1,715 (59.59%) of the unigenes matched with one or more GenBank protein entries and 1,163 (40.41%) had no 'hits'. A cDNA microarray with 2,878 unigenes was developed and used to analyze gene expression profiling of Huanan 124 at key growth stages including seedling, formation of root system, root bulking, and starch maturity. Array data analysis revealed that (1) the higher ratio of up-regulated ribosome-related genes was accompanied by a high ratio of up-regulated ubiquitin, proteasome-related and protease genes in cassava roots; (2) starch formation and degradation simultaneously occur at the early stages of root development but starch degradation is declined partially due to decrease in UDP-glucose dehydrogenase activity with root maturity; (3) starch may also be synthesized in situ in roots; (4) starch synthesis, translocation, and accumulation are also associated probably with signaling pathways that parallel Wnt, LAM, TCS and ErbB signaling pathways in animals; (5) constitutive expression of stress-responsive genes may be due to the adaptation of cassava to harsh environments during long-term evolution.

  8. 水性聚酯对氧化淀粉膜力学性能的影响%Effect of Water-soluble Polyester on Mechanical Property of Oxidized Starch Film

    Institute of Scientific and Technical Information of China (English)

    陈试伟; 朱谱新; 胡晓

    2012-01-01

    Effect of water-soluble polyester on structure and mechanical property of starch film were studied. Oxidized starch/water-soluble polyester blend film with different polyester contents was prepared by adopting casting method. Effect of water-soluble polyester on starch film structure was discussed through ATR-FTIR method and X-ray diffraction method, and mechanical property of starch film was tested. The result shows that formation of hydrogen bonds in oxidized corn starch can be enhanced by water-soluble polyester, and amorphous region and chain entanglement of oxidized corn starch molecules were increased, while there was no hydrogen bond formed between oxidized corn starch and water-soluble polyester molecules. Crystallinity of the starch films is decreased with the increase of the water-soluble polyester content, while the crystallization shape is not affected. Initial modulus of the starch films is decreased by water-soluble polyester,while the breaking elongation of the film is improved. It is pointed out that water-soluble polyester is helpful to modify brittle defect of the starch film.%研究水性聚酯对淀粉浆膜结构和力学性能的影响.采用浇注成膜法制备了不同水性聚酯含量的氧化淀粉/水溶性聚酯混合膜.通过衰减全反射红外法、X-射线衍射法探讨了水性聚酯对淀粉浆膜结构的影响,并测定了浆膜的机械性能.结果表明,水性聚酯促进了氧化玉米淀粉分子间氢键的形成,增加了玉米氧化淀粉分子的链缠结和无定形区,而氧化玉米淀粉与水性聚酯之间并没有氢键形成;水性聚酯含量增加会使浆膜结晶度逐渐下降,但并未对其结晶形态造成影响;水性聚酯降低了浆膜的初始模量,提高了浆膜的断裂伸长.指出:水性聚酯的加入有助于改善淀粉浆膜的脆硬性.

  9. Transcriptome response of cassava leaves under natural shade.

    Science.gov (United States)

    Ding, Zehong; Zhang, Yang; Xiao, Yi; Liu, Fangfang; Wang, Minghui; Zhu, Xinguang; Liu, Peng; Sun, Qi; Wang, Wenquan; Peng, Ming; Brutnell, Tom; Li, Pinghua

    2016-01-01

    Cassava is an important staple crop in tropical and sub-tropical areas. As a common farming practice, cassava is usually cultivated intercropping with other crops and subjected to various degrees of shading, which causes reduced productivity. Herein, a comparative transcriptomic analysis was performed on a series of developmental cassava leaves under both full sunlight and natural shade conditions. Gene expression profiles of these two conditions exhibited similar developmental transitions, e.g. genes related to cell wall and basic cellular metabolism were highly expressed in immature leaves, genes involved in lipid metabolism and tetrapyrrole synthesis were highly expressed during the transition stages, and genes related to photosynthesis and carbohydrates metabolism were highly expressed in mature leaves. Compared with the control, shade significantly induced the expression of genes involved in light reaction of photosynthesis, light signaling and DNA synthesis/chromatin structure; however, the genes related to anthocyanins biosynthesis, heat shock, calvin cycle, glycolysis, TCA cycle, mitochondrial electron transport, and starch and sucrose metabolisms were dramatically depressed. Moreover, the shade also influenced the expression of hormone-related genes and transcriptional factors. The findings would improve our understanding of molecular mechanisms of shade response, and shed light on pathways associated with shade-avoidance syndrome for cassava improvement.

  10. [Degradation of cassava residue by the cellulose degradation composite microbial system MC1].

    Science.gov (United States)

    Guo, Peng; Wang, Xiao-Fen; Zhu, Wan-Bin; Cheng, Xu; Cui, Zong-Jun

    2008-03-01

    The lignocelluloses of cassava residue are good biomass resources. They are mainly used to produce feeds and alcohol. It is a promising approach to utilize them to produce methane. But it is difficult to use cassava residue for producing methane because of its dispersive solid matter and much water. A cellulose degradation composite microbial system MC1 was applied to degrade cassava residue discarded from cassava starch manufactory, and the composition of the lignocelluloses and the soluble ingredients of cassava residue were analyzed. After 18 days' cultivation, the total weight of the cassava residue was reduced by 47.3%, the cellulose, hemi-cellulose and lignin of the cassava residue were reduced by 22.7%, 90.4% and 11.3%, respectively, and 85% of the whole weight relief was made by MC1 within 6 days. The soluble ingredients of the cassava residue were increased from the incipient 18% to 33% in the third day which was the peak value in the process. The total amount of the volatile products, analyzed by GC-MS, came to a maximum in the sixth day. Twelve kinds of volatile products in the fermentation broth were determined, in which ethanol, acetic acid, 1, 2-ethanediol, butanoic acid and glycerine were the major compounds, and they can be utilized by methanogenic organism directly or be changed into compounds that can be utilized by methanogens organism directly. Accordingly, it is very hopeful to use MC1 to degrade cassava residue as a method of prefermentation in methane fermentation.

  11. Domestication Syndrome Is Investigated by Proteomic Analysis between Cultivated Cassava (Manihot esculenta Crantz and Its Wild Relatives.

    Directory of Open Access Journals (Sweden)

    Feifei An

    Full Text Available Cassava (Manihot esculenta Crantz wild relatives remain a largely untapped potential for genetic improvement. However, the domestication syndrome phenomena from wild species to cultivated cassava remain poorly understood. The analysis of leaf anatomy and photosynthetic activity showed significantly different between cassava cultivars SC205, SC8 and wild relative M. esculenta ssp. Flabellifolia (W14. The dry matter, starch and amylose contents in the storage roots of cassava cultivars were significantly more than that in wild species. In order to further reveal the differences in photosynthesis and starch accumulation of cultivars and wild species, the globally differential proteins between cassava SC205, SC8 and W14 were analyzed using 2-DE in combination with MALDI-TOF tandem mass spectrometry. A total of 175 and 304 proteins in leaves and storage roots were identified, respectively. Of these, 122 and 127 common proteins in leaves and storage roots were detected in SC205, SC8 and W14, respectively. There were 11, 2 and 2 unique proteins in leaves, as well as 58, 9 and 12 unique proteins in storage roots for W14, SC205 and SC8, respectively, indicating proteomic changes in leaves and storage roots between cultivated cassava and its wild relatives. These proteins and their differential regulation across plants of contrasting leaf morphology, leaf anatomy pattern and photosynthetic related parameters and starch content could contribute to the footprinting of cassava domestication syndrome. We conclude that these global protein data would be of great value to detect the key gene groups related to cassava selection in the domestication syndrome phenomena.

  12. Domestication Syndrome Is Investigated by Proteomic Analysis between Cultivated Cassava (Manihot esculenta Crantz) and Its Wild Relatives.

    Science.gov (United States)

    An, Feifei; Chen, Ting; Stéphanie, Djabou Mouafi Astride; Li, Kaimian; Li, Qing X; Carvalho, Luiz J C B; Tomlins, Keith; Li, Jun; Gu, Bi; Chen, Songbi

    2016-01-01

    Cassava (Manihot esculenta Crantz) wild relatives remain a largely untapped potential for genetic improvement. However, the domestication syndrome phenomena from wild species to cultivated cassava remain poorly understood. The analysis of leaf anatomy and photosynthetic activity showed significantly different between cassava cultivars SC205, SC8 and wild relative M. esculenta ssp. Flabellifolia (W14). The dry matter, starch and amylose contents in the storage roots of cassava cultivars were significantly more than that in wild species. In order to further reveal the differences in photosynthesis and starch accumulation of cultivars and wild species, the globally differential proteins between cassava SC205, SC8 and W14 were analyzed using 2-DE in combination with MALDI-TOF tandem mass spectrometry. A total of 175 and 304 proteins in leaves and storage roots were identified, respectively. Of these, 122 and 127 common proteins in leaves and storage roots were detected in SC205, SC8 and W14, respectively. There were 11, 2 and 2 unique proteins in leaves, as well as 58, 9 and 12 unique proteins in storage roots for W14, SC205 and SC8, respectively, indicating proteomic changes in leaves and storage roots between cultivated cassava and its wild relatives. These proteins and their differential regulation across plants of contrasting leaf morphology, leaf anatomy pattern and photosynthetic related parameters and starch content could contribute to the footprinting of cassava domestication syndrome. We conclude that these global protein data would be of great value to detect the key gene groups related to cassava selection in the domestication syndrome phenomena.

  13. Growth inhibition of thermotolerant yeast, Kluyveromyces marxianus, in hydrolysates from cassava pulp.

    Science.gov (United States)

    Rugthaworn, Prapassorn; Murata, Yoshinori; Machida, Masashi; Apiwatanapiwat, Waraporn; Hirooka, Akiko; Thanapase, Warunee; Dangjarean, Hatairat; Ushiwaka, Satoru; Morimitsu, Kozo; Kosugi, Akihiko; Arai, Takamitsu; Vaithanomsat, Pilanee

    2014-07-01

    In this study, we report the inhibition of Kluyveromyces marxianus TISTR5925 growth and ethanol fermentation in the presence of furan derivatives and weak acids (acetic acid and lactic acid) at high temperatures. Cassava pulp, obtained as the waste from starch processing, was collected from 14 starch factories located in several provinces of Thailand. At a high temperature (42 °C), the cassava pulp hydrolysate from some starch factories strongly inhibited growth and ethanol production of both K. marxianus (strain TISTR5925) and Saccharomyces cerevisiae (strain K3). HPLC detected high levels of lactic acid and acetic acid in the hydrolysates, suggesting that these weak acids impaired the growth of K. marxianus at high temperature. We isolated Trp-requiring mutants that had reduced tolerance to acetic acid compared to the wild-type. This sensitivity to acetic acid was suppressed by supplementation of the medium with tryptophan.

  14. Brucite nanoplate reinforced starch bionanocomposites

    Science.gov (United States)

    In this paper the mechanical reinforcement in a series of bionanocomposites films based on starch and nano-sized brucite, Mg(OH)2, was investigated. Brucite nanoplates with an aspect ratio of 9.25 were synthesized by wet precipitation and incorporated into starch matrices at different concentrations...

  15. Emissão de folhas e início de acumulação de amido em raízes de uma variedade de mandioca em função da época de plantio Leaf emergence and beginning of starch accumulation in roots of a cassava variety as a function of planting date

    Directory of Open Access Journals (Sweden)

    Alfredo Schons

    2007-12-01

    Full Text Available O número de folhas acumulado (NF na haste principal está associado com o aparecimento de vários estádios de desenvolvimento da cultura da mandioca. O início de acumulação de amido (IAA nas raízes tuberosas da mandioca marca o início da translocação dos fotoassimilados para o principal órgão de reserva nessa espécie. O objetivo deste trabalho foi estimar o filocrono e identificar um indicador morfológico baseado no NF para o IAA em mandioca plantada em diferentes épocas. Um experimento a campo foi conduzido em Santa Maria, RS, Brasil, com quatro épocas de plantio (28/09; 11/10; 16/11 e 27/12/2005. A variedade de mandioca usada foi a "RS 13", plantada em baldes de 12 litros, enterrados no espaçamento com 2,0 x 0,8m. O delineamento experimental foi o inteiramente casualizado com 11 repetições. A soma térmica diária (STd, °C dia foi calculada a partir da emergência e acumulada por: STa = sigmaSTd. O IAA foi determinado nas plantas de cada balde quando uma raiz atingia um diâmetro de 1cm. O NF na data do IAA e o número final de folhas (NFF até o primeiro simpódio também foram determinados. O filocrono variou de 20,3 a 29,5°C dia folha-1 e seus valores foram maiores quanto mais tardio foi o plantio. O NFF variou entre as épocas de plantio, aumentando com o atraso do plantio. O NF no IAA foi similar nas quatro épocas de plantio e ocorreu quando, em média, o NF corresponde a 20,9 (±1,0 folhas.The accumulated number of leaves (NF on the main stem is related to the appearance of several developmental stages in cassava. The beginning of starch accumulation (IAA in the fibrous roots of cassava switches the source/sink ratio because of the translocation of photoassimilates to the major storage organ in this species. This study was aimed at estimating the phyllochron and identifing a morphological indicator based on NF for IAA in cassava grown in several planting dates. A field experiment was carried out in Santa Maria, RS

  16. Two cassava promoters related to vascular expression and storage root formation.

    Science.gov (United States)

    Zhang, Peng; Bohl-Zenger, Susanne; Puonti-Kaerlas, Johanna; Potrykus, Ingo; Gruissem, Wilhelm

    2003-12-01

    Cassava ( Manihot esculenta Crantz) storage roots, organs accumulating large amounts of starch, develop from primary roots via secondary growth. The availability of promoters related to storage-root formation is a prerequisite for engineering root traits in cassava. Two cDNAs, c15 and c54, were identified from a storage-root cDNA library of cassava MCol1505 via differential screening. The transcripts of c15 and c54 were detected in storage roots but not in leaves by Northern analysis. Homology analysis of the deduced amino acid sequences showed that C15 is likely to be related to cytochrome P450 proteins, which are involved in the oxidative degradation of various compounds, while C54 may be related to Pt2L4, a cassava glutamic acid-rich protein. The promoter regions of c15 and c54 were isolated from the corresponding clones in a cassava genomic library. A 1,465-bp promoter fragment ( p15/1.5) of c15 and a 1,081-bp promoter region ( p54/1.0) of c54 were translationally fused to the uidA reporter gene, and introduced into cassava and Arabidopsis thaliana (L.) Heynh. The expression patterns of p15/1.5::uidA and p54/1.0::uidA in transgenic plants showed that both promoters are predominantly active in phloem, cambium and xylem vessels of vascular tissues from leaves, stems, and root systems. More importantly, strong beta-glucuronidase activity was also detected in the starch-rich parenchyma cells of transgenic storage roots. Our results demonstrate that the two promoters are related to vascular expression and secondary growth of storage roots in cassava.

  17. Fermentation and recovery of L-glutamic acid from cassava starch hydrolysate by ion-exchange resin column Produção de ácido L-glutâmico a partir de um hidrolisado de amido de mandioca usando resina de troca iônica

    Directory of Open Access Journals (Sweden)

    K. Madhavan Nampoothiri

    1999-07-01

    Full Text Available Investigations were carried out with the aim of producing L-glutamic acid from Brevibacterium sp. by utilizing a locally available starchy substrate, cassava (Manihot esculenta Crantz. Initial studies were carried out in shake flasks, which showed that even though the yield was high with 85-90 DE (Dextrose Equivalent value, the maximum conversion yield (~34% was obtained by using only partially digested starch hydrolysate, i.e. 45-50 DE. Fermentations were carried out in batch mode in a 5 L fermenter, using suitably diluted cassava starch hydrolysate, using a 85-90 DE value hydrolysate. Media supplemented with nutrients resulted in an accumulation of 21 g/L glutamic acid with a fairly high (66.3% conversation yield of glucose to glutamic acid (based on glucose consumed and on 81.74% theoretical conversion rate. The bioreactor conditions most conducive for maximum production were pH 7.5, temperature 30°C and an agitation of 180 rpm. When fermentation was conducted in fed-batch mode by keeping the residual reducing sugar concentration at 5% w/v, 25.0 g/L of glutamate was obtained after 40 h fermentation (16% more the batch mode. Chromatographic separation by ion-exchange resin was used for the recovery and purification of glutamic acid. It was further crystallized and separated by making use of its low solubility at the isoelectric point (pH 3.2.Pesquisas foram realizadas com o objetivo de produzir ácido glutâmico a partir de Brevibacterium sp. utilizando um substrato disponível na região, a mandioca (Manihot esculenta Crantz. Estudos iniciais, desenvolvidos em shaker, demonstraram que mesmo obtendo elevado rendimento com 85-90 DE (Dextrose Equivalent value, a taxa de conversão máxima (~34% foi obtida usando um hidrolisado de amido parcialmente digerido, i.e. 45-50 DE. As fermentações foram realizadas em um fermentador de 5 L, usando um hidrolisado de amido de mandioca adequadamente diluído, preparado à partir de um valor DE de 85-90. O

  18. Substituição do milho pelo resíduo de fecularia de mandioca sobre o desempenho, digestibilidade e características de carcaça de novilhos confinados = Replacing corn with cassava starch by-products on the performance, digestibility and carcass characteristics of bulls in confinement

    Directory of Open Access Journals (Sweden)

    Maribel Velandia Valero

    2009-10-01

    Full Text Available O efeito de substituição do milho pelo resíduo desidratado de fecularia de mandioca (0; 12,5; 22,8 e 32,7% foi avaliado sobre o desempenho, a digestibilidade e características de carcaça e 32 bovinos mestiços (½ Nelore x ½ Angus de aproximadamente 18 meses de idade e 380 kg de peso vivo. O delineamento experimental foi o inteiramente casualizado, com quatro tratamentos e oito repetições. Foram analisados o ganho médio diário (GMD, rendimento de carcaça (RC, espessura de gordura de cobertura (EGC, área de olho de lombo (AOL, comprimento de perna (CP, espessura de coxão (EC, ingestãode matéria seca (IMS, conversão alimentar (CA, digestibilidade total aparente da matéria seca (DAMS, matéria orgânica (DAMO, proteína bruta (DAPB, energia bruta (DAEB, fibra em detergente ácido (DAFDA e fibra em detergente neutro (DAFDN. O experimento foidesenvolvido durante um período de 56 dias, após 14 dias de adaptação. Os resultados de GMD, RC, CA, EGC, AOL, CP e EC não apresentaram diferenças (p > 0,05 entre os tratamentos. A IMS apresentou redução linear quando o milho foi substituído pelo resíduodesidratado de fecularia de mandioca. Os coeficientes de digestibilidade da MS, MO, PB, EB, FDN e FDA não variaram entre as rações experimentais.The effects of replacing corn with different levels of cassava starch by-products (0; 12.5; 22.8; and 32.7% were evaluated on performance, digestibility and carcass traits of feedlot bulls. Thirty-twocrossbred bulls (½ Nelore x ½ Angus around 18 months of age and 380 kg of body weight were used. A completely randomized design was used, with 4 treatments and 8 replicates. Evaluated traits were: average daily gain (ADG, carcass dressing (CD, backfat thickness (BT, Longissimus area (LDA, leg length (LL and cushion thickness (CT, dry matter intake (DMI, feed conversion ratio (FCR, total apparent digestibility of dry matter (DMDC, organic matter (OMDC, crude protein (CPDC, crude energy (CEDC

  19. Amylopectin small chain glucans form structure fingerprint that determines botanical origin of starch.

    Science.gov (United States)

    Jaiswal, Sarita; Chibbar, Ravindra N

    2017-02-20

    Starch granule size, shape and structure of amylopectin are species specific and influence starch properties and end-use of starch. Amylopectin glucan chain structure was used to predict the starch botanical sources. Mathematical probability for accumulation of small glucan chains DP 6-10 reveal exponential fit curve with maximum R(2) in smallest granule size starches (Chlamydomonas, quinoa, buckwheat). Cereal and cassava showed R(2) of 0.81-0.96 while in pulses and tubers it was less than 0.7. The amylopectin small glucan chains form a unique 'finger print region' that identified starch botanical source. Differential amylopectin chain length distribution (APCLD) graphs between DP 6-80 of all species from Chlamydomonas starch distinguished five structural groups that clustered the 31 analyzed starches into four major patterns. APCLD analyses of amylopectin combined with characteristic pattern of small linear DP (6-9) glucan chains predicted the starch botanical source.

  20. Acid and enzymatic hydrolysis to recover reducing sugars from cassava bagasse: an economic study

    Directory of Open Access Journals (Sweden)

    Woiciechowski Adenise Lorenci

    2002-01-01

    Full Text Available The objective of this work was to study the acid and enzymatic hydrolysis of cassava bagasse for the recovery of reducing sugars and to establish the operational costs. A statistical program "Statistica", based on the surface response was used to optimize the recovery of reducing sugars in both the processes. The process economics was determined considering the values of reducing sugars obtained at laboratory scale, and the operations costs of a cylindrical reactor of 1500 L, with flat walls at the top and bottom. The reactor was operated with 150 kg of cassava bagasse and 1350 kg of water. The yield of the acid hydrolysis was 62.4 g of reducing sugars from 100 g of cassava bagasse containing 66% starch. It represented 94.5% of reducing sugar recovery. The yield of the enzymatic hydrolysis was 77.1 g of reducing sugars from 120 g of cassava bagasse, which represented 97.3% of reducing sugars recovery. Concerning to the time, a batch of acid hydrolysis required 10 minutes, plus the time to heat and cool the reactor, and a batch of the enzymatic hydrolysis needed 25 hours and 20 minutes, plus the time to heat and to cool the reactor. Thus, the acid hydrolysis of 150 kg of cassava bagasse required US$ 34.27, and the enzymatic hydrolysis of the same amount of cassava bagasse required US$ 2470.99.

  1. Efeito da concentração de fibra e parâmetros operacionais de extrusão sobre as propriedades de pasta de misturas de fécula de mandioca e polpa cítrica Effect of the fiber content and operational extrusion parameters on the pasting characteristics of cassava starch and orange pulp mixture

    Directory of Open Access Journals (Sweden)

    Luciana Bronzi de Souza

    2010-09-01

    Full Text Available Para preencher as várias demandas para funcionalidades em produtos alimentícios, a fécula de mandioca misturada à polpa de laranja desidratada foi extrusada sob diferentes condições (0 a 20% de fibras na mistura; (14,6 a 21,4% de umidade e (60,8 a 129 ºC de temperatura de extrusão, objetivando o uso em produtos instantâneos ricos em fibras. A rotação da rosca foi mantida constante em 272 rpm, a abertura da matriz foi 3 mm, a taxa de compressão da rosca foi 3:1 e a taxa de alimentação foi de 150 g/minuto. Os produtos extrusados moídos foram analisados para as propriedades de pasta: viscosidade inicial, pico de viscosidade, quebra de viscosidade, viscosidade final e tendência à retrogradação no Rapid Visco Analyser (RVA, tendo em vista a importância destes parâmetros para este tipo de utilização. Os resultados obtidos mostraram que a porcentagem de fibras foi o parâmetro de maior influência nas propriedades de pasta, e que nas condições de baixo teor de fibras, elevada temperatura e baixa umidade pode ter ocorrido degradação acentuada do amido e solubilização das fibras, levando à redução dos parâmetros de viscosidade.Due the various demands for processed foods with functional ingredients, a mixture of cassava starch and dried orange pulp was extruded under different conditions (0 to 20% of fibers in the mixture; (14.6 to 21.4% moisture; and (60.8 to 129 ºC temperature of extrusion aiming at the use in high fiber instant products. The screw speed was kept constant (272 rpm, the diameter of die was 3 mm, the compression ratio was 3:1, and the feed rate was 150 g/minute. The following pasting properties of the extruded products were analyzed: initial viscosity, peak of viscosity, breakdown, final viscosity, and retrogradation tendency using a Rapid Visco Analyser (RVA in view of the importance of these parameters for such use. The results showed that the percentage of fibers was the greatest variable of influence

  2. Hidratação de tecidos de raízes de mandioca (Manihot esculenta Crantz. e gelatinização do amido durante a cocção Hydration of cassava tissues and starch gelatinization during the cooking process

    Directory of Open Access Journals (Sweden)

    Soraya S. Butarelo

    2004-09-01

    Full Text Available Durante a cocção da mandioca ocorrem modificações físicas e químicas nos tecidos e a textura final é importante para a aceitabilidade e o consumo de mandiocas. A cocção a 80° e em água em ebulição de duas cultivares, aos 12 e 25 meses após o plantio, foi acompanhada determinando-se o ganho de peso (hidratação e o grau de gelatinização das amostras. Gelatinização foi determinada por colorimetria com iodo após dissolução em álcali das amostras cozidas por diferentes períodos de tempo. A 80°C a hidratação e a gelatinização não se completaram, o que ocorreu com a cocção em água em ebulição. O grau de hidratação foi diferente entre cultivares e entre amostras de 12 e 25 meses de plantio e pode ser descrito matematicamente por modelo de ordem zero. Amostras colhidas 12 meses após ao plantio hidrataram mais rápido que aos 25 meses e a cultivar IAPAR-19 Pioneira hidratou mais rápido que a cultivar Catarina Amarela. Quanto mais rápida a hidratação mais rápido o cozimento e quanto maior a hidratação maior o rendimento em produto cozido.Cooking of cassava root tissues causes both physical and chemical modifications and the final texture of the product is important for the acceptability and consumption of the food. Cooking tissue samples at 80° and in boiling water from two cultivars, harvested 12 and 25 months after planting date, was accompanied by determinig weight gain and starch gelatinization of the samples. Starch gelatinization was determined by colorimetry with iodine after solubilization in alkali of samples cooked for different period of times. At 80°C neither hydration or gelatinization were complete, which occurred at in boiling water. Hydration was different between cultivars and harvesting ages and could be described by a zero order mathematical model. Samples harvested 12 months after planting date hydrated faster than the ones harvested after 25 months and IAPAR-19 Pioneira hydrated faster

  3. Obtenção de nanocelulose da fibra de coco verde e incorporação em filmes biodegradáveis de amido plastificados com glicerol

    Directory of Open Access Journals (Sweden)

    Bruna A. S. Machado

    2014-01-01

    Full Text Available Composites strengthened with nanocellulose have been developed with the aim of improving mechanical, barrier, and thermal properties of materials. This improvement is primarily due to the nanometric size and the high crystallinity of the incorporated cellulose. Cassava starch films plasticized with glycerol and incorporated with nanocellulose from coconut fibers were developed in this study. The effect of this incorporation was studied with respect to the water activity, solubility, mechanical properties, thermal analysis, and biodegradability. The study demonstrated that the film properties can be significantly altered through the incorporation of small concentrations of nanocellulose.

  4. Use of Cassava Peel as Carbon Source for Production of Amylolytic Enzymes by Aspergillus niveus

    OpenAIRE

    SILVA, Tony Marcio; ALARCON, Ricardo Fernandes; DAMASIO, Andre Ricardo de Lima; Michelin, Michele; Maller, Alexandre; Douglas C. Masui; TERENZI, Hector Francisco; Jorge, Joao Atilio; Polizeli, Maria de Lourdes T. M.

    2009-01-01

    Aspergillus niveus produced high levels of alpha-amylase and glucoamylase in submerged fermentation using the agricultural residue cassava peel as a carbon source. In static conditions, the amylase production was substantially greater than in the agitated condition. The optimized culture conditions were initially at pH 5.0, 35 degrees C during 48 hours. Amylolytic activity was still improved (50%) with a mixture of cassava peel and soluble starch in the proportion 1:1 (w/w). The crude extract...

  5. Cassava as an energy crop

    DEFF Research Database (Denmark)

    Kristensen, Søren Bech Pilgaard; Birch-Thomsen, Torben; Rasmussen, Kjeld;

    2014-01-01

    , which represent two major agro-ecological environments in the Soudan-zone in Mali. The results reveal that farmers are experienced cassava producers and are interested in an expansion of cassava cultivation for bioethanol production and that suitable areas are available, especially for an expansion...

  6. The effect of the addition of sorbitol and glycerol towards the edible film characteristics of the belitung taro starch and the lime leaves as antimicrobial

    Science.gov (United States)

    Asria, Merry; Elizarni, Samah, dan Selfa Dewati

    2015-12-01

    Plastics have been generally used for food packaging, but plastics using causing environmental problem for as non biodegradable. Resolving the problem need another alternative packaging that environmental friendly such as the edible film as biodegradable packing material. This research intend to determination the effects of sorbitol and glycerol (concentration of 1%, 2%, 3%, and 4%) as addition to the edible film characteristics from the belitung taro starch (Xanthosoma sagitifolium). Lime leaves (Citrus aurantifolia) extract used as an antimicrobial film (2%, 4%, 6%, 8%, and 10% respectively). From the research obtained that using sorbitol has given more rigid and hard film texture, while glycerol provides more elastic and flexible texture. Sorbitol give best performance at 2% where thickness 0.17 mm; tensile strength 41.60 MPa; yield strength 34.28 MPa; modulus of elasticity 7983.71 MPa; and maximum strain 29,8%. While, glycerol (2%) provides thickness 0.18 mm; tensile strength 35.72 MPa; yield strength 30.78 MPa; modulus of elasticity 9065.90 MPa; and maximum strain 14.4% for best performance. SEM and FTIR analysis applied to determine film surface morphology's characterization and determine the functional groups of the film materials. The addition of lime leaves extract as antimicrobial gives the growth inhibition activity against the Staphylococcus aureus bacteria.

  7. Sensorial evolution of cassava flour (Manihot esculenta crantz) added to protein concentrate cassava leaves

    OpenAIRE

    Lima, Elaine C S; Feijo, Márcia B S; Freitas, Maria C J; dos Santos, Edna R; Armando U.O. SABAA-SRUR; Moura, Luciana S M

    2012-01-01

    Cassava is regarded as the nutritional base of populations in developing countries, and flour, product made of cassava, is the most consumed in the world. The cassava leaves are very rich in vegetable proteins, but a big amount is lost in processing the crop. The objective of this study was to do a sensory evaluation of cassava flour to which a protein concentrate obtained from cassava leaves (CPML) was added. The CPML was obtained from cassava leaves by isoelectric precipitation and added to...

  8. Comparative Proteome Analysis of the Tuberous Roots of Six Cassava (Manihot esculenta) Varieties Reveals Proteins Related to Phenotypic Traits.

    Science.gov (United States)

    Schmitz, Gabriela Justamante Händel; de Magalhães Andrade, Jonathan; Valle, Teresa Losada; Labate, Carlos Alberto; do Nascimento, João Roberto Oliveira

    2016-04-27

    Cassava (Manihot esculenta Crantz) is a staple food and an important source of starch, and the attributes of its tuberous root largely depend on the variety. The proteome of cassava has been investigated; however, to date, no study has focused on varieties that reveal the molecular basis of phenotypical characteristics. Therefore, we aimed to compare the proteome of the tuberous roots of six cassava varieties that differed in carbohydrates, carotenoids, and resistance to diseases, among other attributes. Two-dimensional gels showed 146 differential spots between the varieties, and the functional roles of some differential proteins were correlated to phenotypic characteristics of the varieties, such as the amount of carbohydrates or carotenoids and the resistance to biotic or abiotic stresses. The results obtained here highlight elements that might help to direct the improvement of new cultivars of cassava, which is an economically and socially relevant crop worldwide.

  9. Influence of Mucilage Viscosity On The Globule Structure And Stability Of Certain Starch Emulsions

    Directory of Open Access Journals (Sweden)

    Uhumwangho MU

    2005-05-01

    Full Text Available A study was carried out to determine the influence of mucilage viscosity on the globule structure (i.e. size and number of certain starch emulsions. The starches investigated were cassava, potato and maize. The emulsions were prepared by mixing the starch mucilage of a predetermined concentration 4%w/v with arachis oil in the ratio 50:50, using a silverson mixer fitted with a dispersator head. The emulsions were stored at room temperature (28±20C for 7 days. Changes in globule size were monitored by photomicroscopy. Viscosities of the mucilage and those of resulting emulsions were determined using a capillary flow method. The viscosities of the emulsions expressed as time of flow (seconds, were 680 (cassava starch, 369 (potato starch and 270 (Maize starch, and for the mucilage 510 (cassava, 336 (potato and 248 (maize. The corresponding mean globule sizes of the fresh emulsions were (µm 28±6, 42±6 and 45±5 respectively. The increase in globule size during storage (measure of globule coalescence rate was 1.8±0.2µm day -1 (cassava, 3.5±0.2µm day -1 (potato and 4.6±0.3µm day -1 (maize. Thus, a higher viscosity of the dispersion medium is associated with the production of finer and more stable emulsions.

  10. Preparation and Characterization of Release Film from Corn Starch%玉米淀粉基缓释膜的制备及表征

    Institute of Scientific and Technical Information of China (English)

    杨铁金; 王琦; 厉悦; 刘敏; 刘亚红

    2011-01-01

    [ Objective ] The research aimed to study the preparation and characterization of release film from corn starch. [ Method ] The coated fertilizer was prepared by coating material,which was synthesized by corn starch,polyvinyl alcohol (PVA) and additives. Effects of additives included in coating materials on the slow-release fertilizer were studied in detail. The construction of the membrane was analyzed and characterized by IR spectrum and TG. The effectible factors and optimum conditions of the membranes prepared were investigated. [ Result ] The best reaction condition of the preparation of release film from corn starch was as following:starch:PVA = 1∶1 ,PVA content of 15% ,tween of 0.2 ml,urea of 0.5 g, glycerin of 1.5 g, formaldehyde of 2 ml, borax of 0.2 g, evocator of 0.5 %, reaction for 30 min, reaction temperature of 80 ℃.[ Conclusion ] The release film has characteristics of low cost, biodegradation, no pollution.%[目的]研究玉米淀粉基缓释膜的制备条件及特征.[方法]以玉米淀粉与聚乙烯醇为原料,在交联剂的作用下,制得包膜料液,用此料液给尿素涂膜,制得包膜尿素.通过红外光谱时膜的结构进行表征和分析,研究改性淀粉膜的形成条件和影响因素.[结果]制备玉米淀粉基缓释膜的最佳反应条件是淀粉和PVA的质量比为1:1,PVA的含量为15%,吐温0.2 ml,尿素0.5 g,丙三醇1.5 g,甲醛2ml,硼砂0.2 g,引发剂用量0.5%,反应30 min,反应温度控制在80℃.[结论]制备得到的包膜材料具有成本低、可生物降解、无环境污染等特点.

  11. Dark hydrogen fermentation from hydrolyzed starch treated with recombinant amylase originating from Caldimonas taiwanensis On1.

    Science.gov (United States)

    Chen, Shing-Der; Sheu, Der-Shyan; Chen, Wen-Ming; Lo, Yung-Chung; Huang, Tian-I; Lin, Chiu-Yue; Chang, Jo-Shu

    2007-01-01

    Starch is one of the most abundant resources on earth and is suited to serve as a cost-effective feedstock for biological hydrogen production. However, producing hydrogen from direct fermentation of starch is usually inefficient, as the starch hydrolysis is often the rate-limiting step. Therefore, in the present work, enzymatic starch hydrolysis was conducted to enhance the feasibility of using starch feedstock for H2 production. The amylase (with a molecular weight of ca. 112 kDa) used for starch hydrolysis was produced from a recombinant E. coli harboring an amylase gene originating from Caldimonas taiwanensis On1. Using statistical experimental design, the optimal pH and temperature for starch hydrolysis with the recombinant amylase was pH 6.86 and 52.4 degrees C, respectively, at an initial starch concentration of 7 g/L. The hydrolyzed products contained mainly glucose, maltotriose, and maltotetrose, while a tiny amount of maltose was also detected. The enzymatically hydrolyzed products of soluble starch and cassava starch were used as the substrate for dark hydrogen fermentation using Clostridium butyricum CGS2 and Clostridium pasteurianum CH4. The highest H2 production rate (vH2) and yield (YH2) of C. butyricum CGS2 was 124.0 mL/h/L and 6.32 mmol H2/g COD, respectively, both obtained with the hydrolysate of cassava starch. The best H2 production rate (63.0 mL/h/L) of C. pasteurianum CH4 occurred when using hydrolyzed cassava starch as the substrate, whereas the highest yield (9.95 mmol H2/g COD) was obtained with the hydrolyzed soluble starch.

  12. The management of cassava toxicity and its changing sociocultural context in the Kei Islands, eastern Indonesia.

    Science.gov (United States)

    Soselisa, Hermien L; Ellen, Roy

    2013-01-01

    Over a period of 150 years the Kei Islands have undergone environmental change, from rainforest to dryland savanna woodland. This has been accompanied by a shift in starch staple from sago, tubers, and grain to cassava. We show how this has been an effective ecological adaptation with social ramifications, not least the adoption of bitter cassava as a cultural identity marker. One of the problems of bitter cassava diets where people have become dependent upon them in poor parts of the Old World tropics are the effects of toxicity. We show how through a combination of factors and strategies this has not been a major issue in the Kei Islands, and how through a government-assisted agricultural project, attempts are being made to build upon this successful transition. The viability of present trends are evaluated.

  13. Genomics approaches to unlock the high yield potential of cassava, a tropical model plant

    Directory of Open Access Journals (Sweden)

    Shengkui ZHANG,Ping'an MA,Haiyan WANG,Cheng LU,Xin CHEN,Zhiqiang XIA,Meiling ZOU,Xinchen ZHOU,Wenquan WANG

    2014-12-01

    Full Text Available Cassava, a tropical food, feed and biofuel crop, has great capacity for biomass accumulation and an extraordinary efficiency in water use and mineral nutrition, which makes it highly suitable as a model plant for tropical crops. However, the understanding of the metabolism and genomics of this important crop is limited. The recent breakthroughs in the genomics of cassava, including whole-genome sequencing and transcriptome analysis, as well as advances in the biology of photosynthesis, starch biosynthesis, adaptation to drought and high temperature, and resistance to virus and bacterial diseases, are reviewed here. Many of the new developments have come from comparative analyses between a wild ancestor and existing cultivars. Finally, the current challenges and future potential of cassava as a model plant are discussed.

  14. High surface area activated carbon prepared from cassava peel by chemical activation.

    Science.gov (United States)

    Sudaryanto, Y; Hartono, S B; Irawaty, W; Hindarso, H; Ismadji, S

    2006-03-01

    Cassava is one of the most important commodities in Indonesia, an agricultural country. Cassava is one of the primary foods in our country and usually used for traditional food, cake, etc. Cassava peel is an agricultural waste from the food and starch processing industries. In this study, this solid waste was used as the precursor for activated carbon preparation. The preparation process consisted of potassium hydroxide impregnation at different impregnation ratio followed by carbonization at 450-750 degrees C for 1-3 h. The results revealed that activation time gives no significant effect on the pore structure of activated carbon produced, however, the pore characteristic of carbon changes significantly with impregnation ratio and carbonization temperature. The maximum surface area and pore volume were obtained at impregnation ratio 5:2 and carbonization temperature 750 degrees C.

  15. Synthesis of grafted flocculants based on several kinds of starch and its performance in water turbidity removal

    OpenAIRE

    Kaavessina Mujtahid; Distantina Sperisa; Fadilah

    2017-01-01

    Taro starch, cassava starch and also their modified were prepared as a backbone of grafted flocculants. These flocculants were synthesized by combining the properties of synthetic and natural polymer via the ‘grafting to’ method that separated into two stages. The first stage was synthesizing of non-terminated polyacrylamide (nt-PAM) and then followed by the second stage grafting of the nt-PAM onto several kinds of starch. The intrinsic viscosity (η) and average molecular weight (Mv) of starc...

  16. Processing of cassava to produce ethanol - effect of raw material preparation

    Energy Technology Data Exchange (ETDEWEB)

    Greenfield, P.F.; Brooks, R.B.

    1982-06-01

    The effect of disintegration severity on starch hydrolysis and ethanol production from cassava roots and stems has been evaluated. It was found that a considerable fraction of the starch in the roots was made available for hydrolysis with relatively crude processing; all such material was readily fermented. To achieve a very high fermentables yield, either very intensive processing or, preferably, a two stage process, with the second stage being applied only to the oversize material, is required. Whether it is economically viable to process the oversize material further depends on a number of site-specific factors. The two stage option appears the more attractive alternative especially in small to medium size cassava to ethanol plants because of the need to minimise power requirements and thereby steam usage.

  17. Synthesis of grafted flocculants based on several kinds of starch and its performance in water turbidity removal

    Directory of Open Access Journals (Sweden)

    Kaavessina Mujtahid

    2017-01-01

    Full Text Available Taro starch, cassava starch and also their modified were prepared as a backbone of grafted flocculants. These flocculants were synthesized by combining the properties of synthetic and natural polymer via the ‘grafting to’ method that separated into two stages. The first stage was synthesizing of non-terminated polyacrylamide (nt-PAM and then followed by the second stage grafting of the nt-PAM onto several kinds of starch. The intrinsic viscosity (η and average molecular weight (Mv of starches-g-PAM were observed and their molecular structures were analyzed by using Fourier Transform Infra-Red (FTIR. Finally, the obtained flocculants were tested to evaluate their performance for the treatment of the simulated water turbidity containing 10 g of kaolin in 1000 ml of aquadest. The results showed that all the grafted flocculants can be good comparable to some commercial organic flocculants. The percentages of the water turbidity removal for each of backbones are 93.6% (taro starch, 91.2% (cassava starch, 95.3% (modified taro starch and 94.1% (modified cassava starch. It can be highlighted that the modified taro starch exhibited the best performance in water turbidity removal up to 95%.

  18. Redução da hidrofilicidade de filmes biodegradáveis à base de amido por meio de polimerização por plasma Reduction of hydrophilicity of biodegradable starch-based films by plasma polymerization

    Directory of Open Access Journals (Sweden)

    Rossana M. S. M. Thiré

    2004-03-01

    Full Text Available Devido ao baixo custo de produção e excelente biodegradabilidade, o amido constitui-se em matéria-prima promissora para a produção de plásticos biodegradáveis. No entanto, a grande hidrofilicidade dos filmes à base de amido representa uma séria limitação tecnológica à sua comercialização, uma vez que as propriedades dos filmes são afetadas pela variação da umidade relativa do ar durante a sua estocagem ou o seu uso. Neste trabalho, filmes de amido termoplástico foram recobertos com uma fina camada protetora polimérica gerada por intermédio da tecnologia de plasma frio. 1-Buteno e 1,3-butadieno foram utilizados como monômeros para a polimerização por plasma. Os filmes recobertos apresentaram uma redução de até 80% na absorção de água e aumento do ângulo de contato em relação à água. Estes resultados indicaram uma redução significativa na natureza hidrofílica do material à base de amido após o recobrimento.Due to low cost and excellent biodegradability, the use of starch as a raw material for bioplastic production is growing in interest. However, the properties of starch-based materials are affected by relative humidity during their use and storage due to their hydrophilic character. In this work, thermoplastic cornstarch films were coated by cold plasma technology with a protective thin layer in order to reduce water sensitivity. 1-Butene and 1,3-butadiene were used as monomers for plasma polymerization. Coated films presented a reduction of water absorption up to 80% an increase in contact angle related to water. These results indicated that the coating process reduced significantly the hydrophilic nature of the starch-based materials.

  19. Conversion of cassava wastes for biofertilizer production using phosphate solubilizing fungi.

    Science.gov (United States)

    Ogbo, Frank C

    2010-06-01

    Two fungi characterized as Aspergillus fumigatus and Aspergillus niger, isolated from decaying cassava peels were used to convert cassava wastes by the semi-solid fermentation technique to phosphate biofertilizer. The isolates solubilized Ca(3)(PO(4))(2), AlPO(4) and FePO(4) in liquid Pikovskaya medium, a process that was accompanied by acid production. Medium for the SSF fermentation was composed of 1% raw cassava starch and 3% poultry droppings as nutrients and 96% ground (0.5-1.5mm) dried cassava peels as carrier material. During the 14days fermentation, both test organisms increased in biomass in this medium as indicated by increases in phosphatase activity and drop in pH. Ground cassava peels satisfied many properties required of carrier material particularly in respect of the organisms under study. Biofertilizer produced using A. niger significantly (p<.05) improved the growth of pigeon pea [Cajanus cajan (L.) Millsp.] in pot experiments but product made with A. fumigatus did not.

  20. Cloning and characterization of a tuberous root-specific promoter from cassava (Manihot esculenta Crantz).

    Science.gov (United States)

    Koehorst-van Putten, Herma J J; Wolters, Anne-Marie A; Pereira-Bertram, Isolde M; van den Berg, Hans H J; van der Krol, Alexander R; Visser, Richard G F

    2012-12-01

    In order to obtain a tuberous root-specific promoter to be used in the transformation of cassava, a 1,728 bp sequence containing the cassava granule-bound starch synthase (GBSSI) promoter was isolated. The sequence proved to contain light- and sugar-responsive cis elements. Part of this sequence (1,167 bp) was cloned into binary vectors to drive expression of the firefly luciferase gene. Cassava cultivar Adira 4 was transformed with this construct or a control construct in which the luciferase gene was cloned behind the 35S promoter. Luciferase activity was measured in leaves, stems, roots and tuberous roots. As expected, the 35S promoter induced luciferase activity in all organs at similar levels, whereas the GBSSI promoter showed very low expression in leaves, stems and roots, but very high expression in tuberous roots. These results show that the cassava GBSSI promoter is an excellent candidate to achieve tuberous root-specific expression in cassava.

  1. Expression Profiling of Cassava Storage Roots Reveals an Active Process of Glycolysis/Gluconeogenesis

    Institute of Scientific and Technical Information of China (English)

    Jun Yang; Dong An; Peng Zhang

    2011-01-01

    Mechanisms related to the development of cassava storage roots and starch accumulation remain largely unknown. To evaluate genome-wide expression patterns during tuberization, a 60 mer oligonucleotide microarray representing 20 840 cassava genes was designed to identify differentially expressed transcripts in fibrous roots, developing storage roots and mature storage roots. Using a random variance model and the traditional twofold change method for statistical analysis, 912 and 3 386 upregulated and downregulated genes related to the three developmental phases were identified. Among 25 significantly changed pathways identified, glycolysislgluconeogenesis was the most evident one. Rate-limiting enzymes were identified from each individual pathway, for example, enolase, L-lactate dehydrogenase and aldehyde dehydrogenase for glycolysis/gluconeogenesis, and ADP-glucose pyrophosphorylase, starch branching enzyme and glucan phosphorylase for sucrose and starch metabolism. This study revealed that dynamic changes in at least 16% of the total transcripts, including transcription fac-tors, oxidoreductasesltransferaseslhydrolases, hormone-related genes, and effectors of homeostasis. The reliability of these differentially expressed genes was verified by quantitative real-time reverse transcription-polymerase chain reaction. These studies should facilitate our understanding of the storage root formation and cassava improvement.

  2. An evaluation of cassava, sweet potato and field corn as potential carbohydrate sources for bioethanol production in Alabama and Maryland

    Energy Technology Data Exchange (ETDEWEB)

    Ziska, Lewis H.; Tomecek, Martha; Sicher, Richard [United States Department of Agriculture, Agricultural Research Service, Crop Systems and Global Change Lab, 10300 Baltimore Avenue, Building 1, Beltsville, MD 20705 (United States); Runion, G. Brett; Prior, Stephen A.; Torbet, H. Allen [United States Department of Agriculture, Agricultural Research Service, National Soil Dynamics Laboratory, 411 South Donahue Drive, Auburn, AL 36832 (United States)

    2009-11-15

    The recent emphasis on corn production to meet the increasing demand for bioethanol has resulted in trepidation regarding the sustainability of the global food supply. To assess the potential of alternative crops as sources of bioethanol production, we grew sweet potato (Ipomoea batatas) and cassava (Manihot esculentum) at locations near Auburn, Alabama and Beltsville, Maryland in order to measure root carbohydrate (starch, sucrose, glucose) and root biomass. Averaged for both locations, sweet potato yielded the highest concentration of root carbohydrate (ca 80%), primarily in the form of starch (ca 50%) and sucrose (ca 30%); whereas cassava had root carbohydrate concentrations of (ca 55%), almost entirely as starch. For sweet potato, overall carbohydrate production was 9.4 and 12.7 Mg ha{sup -1} for the Alabama and Maryland sites, respectively. For cassava, carbohydrate production in Maryland was poor, yielding only 2.9 Mg ha{sup -1}. However, in Alabama, carbohydrate production from cassava averaged {proportional_to}10 Mg ha{sup -1}. Relative to carbohydrate production from corn in each location, sweet potato and cassava yielded approximately 1.5 x and 1.6 x as much carbohydrate as corn in Alabama; 2.3 x and 0.5 x for the Maryland site. If economical harvesting and processing techniques could be developed, these data suggest that sweet potato in Maryland, and sweet potato and cassava in Alabama, have greater potential as ethanol sources than existing corn systems, and as such, could be used to replace or offset corn as a source of biofuels. (author)

  3. Starch Applications for Delivery Systems

    Science.gov (United States)

    Li, Jason

    2013-03-01

    Starch is one of the most abundant and economical renewable biopolymers in nature. Starch molecules are high molecular weight polymers of D-glucose linked by α-(1,4) and α-(1,6) glycosidic bonds, forming linear (amylose) and branched (amylopectin) structures. Octenyl succinic anhydride modified starches (OSA-starch) are designed by carefully choosing a proper starch source, path and degree of modification. This enables emulsion and micro-encapsulation delivery systems for oil based flavors, micronutrients, fragrance, and pharmaceutical actives. A large percentage of flavors are encapsulated by spray drying in today's industry due to its high throughput. However, spray drying encapsulation faces constant challenges with retention of volatile compounds, oxidation of sensitive compound, and manufacturing yield. Specialty OSA-starches were developed suitable for the complex dynamics in spray drying and to provide high encapsulation efficiency and high microcapsule quality. The OSA starch surface activity, low viscosity and film forming capability contribute to high volatile retention and low active oxidation. OSA starches exhibit superior performance, especially in high solids and high oil load encapsulations compared with other hydrocolloids. The submission is based on research and development of Ingredion

  4. Inducing PLA/starch compatibility through butyl-etherification of waxy and high amylose starch.

    Science.gov (United States)

    Wokadala, Obiro Cuthbert; Emmambux, Naushad Mohammad; Ray, Suprakas Sinha

    2014-11-04

    In this study, waxy and high amylose starches were modified through butyl-etherification to facilitate compatibility with polylactide (PLA). Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy and wettability tests showed that hydrophobic butyl-etherified waxy and high amylose starches were obtained with degree of substitution values of 2.0 and 2.1, respectively. Differential scanning calorimetry, tensile testing, and scanning electron microscopy (SEM) demonstrated improved PLA/starch compatibility for both waxy and high amylose starch after butyl-etherification. The PLA/butyl-etherified waxy and high amylose starch composite films had higher tensile strength and elongation at break compared to PLA/non-butyl-etherified composite films. The morphological study using SEM showed that PLA/butyl-etherified waxy starch composites had a more homogenous microstructure compared to PLA/butyl-etherified high amylose starch composites. Thermogravimetric analysis showed that PLA/starch composite thermal stability decreased with starch butyl-etherification for both waxy and high amylose starches. This study mainly demonstrates that PLA/starch compatibility can be improved through starch butyl-etherification.

  5. Development of cassava cake enriched with its own bran and Spirulina platensis - doi: 10.4025/actascitechnol.v34i4.10687

    Directory of Open Access Journals (Sweden)

    Meire Franci Polonio Navacchi

    2012-10-01

    Full Text Available The cassava cake was developed enriching it with a biomass of Spirulina platensis and a type of bran made out of its own starch. This biomass, a part from being rich in protein, also contains vitamins, essential fatty acids and minerals. Around Umuarama, in the State of Paraná, there is an agricultural/industrial complex annually producing and processing tons of cassava. Baked goods can be elaborated based in cassava as a way to expand the use of this raw material and to produce food free of gluten to celiac people. In this complex a solid byproduct is generated, which is rich in starch and fibres, and because of its low commercial value it is used for animal feed or discarded. The bran was dehydrated and analysed microbiologically as well as physically and chemically so as to be used in applied research. Developed energetic food based on cassava lacks protein, but this can be supplied by adding the biomass of Spirulina platensis. Different formulations of this cassava cake were developed varying the concentration of Spirulina platensis and cassava bran. The formulation that presented the best features received chocolate before being submitted to sensory tests by children in the public education system. The results show an excellent acceptance which made viable the development of this product because of aspects like nutrition, technology and sensorial.

  6. Identification, isolation and quantification of representative bacteria from fermented cassava dough using an integrated approach of culture-dependent and culture-independent methods.

    Science.gov (United States)

    Miambi, Edouard; Guyot, Jean-Pierre; Ampe, Frédéric

    2003-04-25

    The use of denaturing gradient gel electrophoresis (DGGE) and traditional culture-depending methods for examining the bacterial community of traditional cassava starch fermentation were investigated. It appeared that DGGE profiles of total DNA of cassava dough exhibited 10 distinguishable bands. In contrast, DGGE fingerprints of bacteria recovered from enrichment cultures of fermented dough gave variable profiles containing fewer bands. Bands corresponding to five bacterial species detected by direct PCR-DGGE of total DNA from of cassava dough were also observed in DGGE patterns of enrichment cultures. Eighteen strains were isolated from cultures selected on the basis of their DGGE banding patterns. Assessment of bacterial identification by 16S rDNA sequence similarity revealed that band comigration implied sequence identity. Comparison of 16S rDNA sequences of excised DGGE bands and recovered pure culture isolates with those in GENBANK and the RDP databases revealed that representative bacteria of fermented cassava dough were Lactobacillus and Pediococcus species as well as species of Clostridium, Propionibacterium and Bacillus. Some Lactobacillus species detected in dough samples by sequence analysis of DGGE bands were not recovered in any of the five culture media and conditions used. On the other hand, some species recovered as pure cultures from enrichments were not detected by direct DGGE analysis of total bacterial DNA from cassava dough. Our results provide evidence of the necessity to combine both culture-dependent and culture-independent methods for better description of microbial communities in indigenous cassava starch fermentations.

  7. Starch composites with aconitic acid.

    Science.gov (United States)

    Gilfillan, William Neil; Doherty, William O S

    2016-05-05

    The aim of this project is to examine the effectiveness of using aconitic acid (AcA), a tricarboxylic acid which contains a carbon/carbon double bond (CC), to enhance the properties of starch-based films. Starch/glycerol cast films were prepared with 0, 2, 5, 10 and 15wt% AcA (starch wt% basis) and the properties analysed. It was shown that AcA acted as both a cross-linking agent and also a strong plasticising agent. The 5wt% AcA derived starch films were the most effectively cross-linked having the lowest solubility (28wt%) and decreased swelling coefficient (35vol.%) by approximately 3 times and 2.4 times respectively compared to the control film submerged in water (23°C). There was also a significant increase in the film elongation at break by approximately 35 times (compared to the control) with the addition of 15wt% AcA, emphasising the plasticising effect of AcA. However, generally there was a reduced tensile strength, softening of the film, and reduced thermal stability with increased amounts of AcA.

  8. Film with anthocyanins as an indicator of chilled pork deterioration

    Directory of Open Access Journals (Sweden)

    Luana Baptista Golasz

    2013-02-01

    Full Text Available An indicator can be defined as a substance which indicates the presence or absence of another substance or the degree of a certain reaction through characteristic changes, especially color. Therefore, the aim of this work is to evaluate the performance of a bio-based film with anthocyanin as an indicator of chilled pork deterioration. A film made of cassava starch, glycerol, and grape anthocyanins was prepared using the casting technique. Pork loin samples were put in Petri dishes containing an anthocyanin film on the bottom and stored at 4 ºC. Psychrotrophic microorganism count and the pH of the pork loin samples were analyzed for a 14 day- period. At the same time, the films were subjected to colorimetric analysis using D65 illuminant and the CIELAB system. Chroma and hue angle data for these films were evaluated by Anova and Dunnett's test. An increase in the microbial population and in the pH was observed over the storage period as result of pork deterioration. Color changes were also identified in the film. However, only at the beginning of the storage period was it possible to establish a correlation between film color and pork deterioration. The shelf life end-point could not be clearly detected by the film.

  9. 柠檬酸氢二铵改善淀粉浆料成膜性的研究%Study on Size Film Property of Modified Starch with Diammonium Hydrogen Citrate

    Institute of Scientific and Technical Information of China (English)

    沈艳琴; 武海良; 周丹

    2012-01-01

    Effect of using diammonium hydrogen citrate to improve modified starch size film property was discussed. Basic properties of diammonium hydrogen citrate were introduced. Diammonium hydrogen citrate was selected as size mixture plasticizer,adhesion and size film property of modified starch sizing were tested when adding different contents of diammonium hydrogen citrate, then the sized yam were tested. The lest shows that strength, hairiness and wear resistance of pure cotton yam or polyester cotton blended yarn can be improved when adding proper diammonium hydrogen citrate in modified starch. It is considered that size film property can be improved, starch sizing quality can be improved when adding proper diammonium hydrogen citrate in modified starch.%探讨柠檬酸氢二铵在改善变性淀粉浆料浆膜硬脆性上的效果.介绍了柠檬酸氢二铵的基本性能,采用柠檬酸氢二铵作为浆料增塑剂,测试了不同柠檬酸氢二铵含量的变性淀粉浆液的黏附性和成膜性能,并进行了浆纱试验.试验表明,在变性淀粉中加入适量的柠檬酸氢二铵,有助于提高纯棉浆纱和涤棉浆纱的强力、毛羽降低率和耐磨性.认为:柠檬酸氢二铵以适当比例加入到变性淀粉中,能有效改善浆膜性能,提高淀粉浆上浆质量.

  10. Simultaneous non-thermal saccharification of cassava pulp by multi-enzyme activity and ethanol fermentation by Candida tropicalis.

    Science.gov (United States)

    Rattanachomsri, Ukrit; Tanapongpipat, Sutipa; Eurwilaichitr, Lily; Champreda, Verawat

    2009-05-01

    Cassava pulp, a solid by-product from starch processing, is a promising and underused biomass that can be converted to biofuels and other value-added bio-products. In this study, an alternative cassava pulp saccharification process, which utilizes the multi-activity enzyme from Aspergillus niger BCC17849 and obviates the need for a pre-gelatinization step, was developed. The crude multi-enzyme composed of non-starch polysaccharide hydrolyzing enzyme activities, including cellulase, pectinase and hemicellulase act cooperatively to release the trapped starch granules from the fibrous cell wall structure for subsequent saccharification by raw starch degrading activity. A high yield of fermentable sugars, equivalent to 716 mg glucose and 67 mg xylose/g of cassava pulp, was obtained after 48 h incubation at 40 degrees C and pH 5 using the multi-enzyme, which was greater than the yield obtained from the optimized combinations of the corresponding commercial enzymes. The multi-enzyme saccharification reaction can be performed simultaneously with the ethanol fermentation process using a thermotolerant yeast Candida tropicalis BCC7755. The combined process produced 14.3 g/l ethanol from 4% (w/v) cassava pulp after 30 h of fermentation. The productivity rate of 0.48 g/l/h is equivalent to 93.7% of the theoretical yield based on total starch and cellulose, or 85.4% based on total fermentable sugars. The non-thermal enzymatic saccharification process described is more energy efficient and yields more fermentable sugar than the conventional enzymatic process. Furthermore, the process is applicable for production of various bio-products of economic importance.

  11. Effect of starch cross-linking using STMP on properties of starch sizes%STMP交联变性对淀粉浆料性能的影响

    Institute of Scientific and Technical Information of China (English)

    郑浩; 祝志峰

    2013-01-01

    In order to find environmentally friendly cross-linking agents suitable for the modification of cassava starch used for warp sizing for the purposes of replacing the toxic cross-linking agents commonly used in the production of the starch sizes and meeting the demands of viscosity thermal stability of the cooked starch pastes during warp sizing operation, a series of cross-linked starch with different degrees of crosslinking ( DC ) were prepared by using non-toxic sodium trimetaphosphate ( STMP) as the crosslinking agent through varying the feed ratio of STMP to the starch. Influences of DC on the paste viscosity, viscosity and thermal stability, adhesion to fiber, film properties, de-sizing behavior, BOD5 and COD were studied. It was found that STMP crosslinking agent could significantly improve the viscosity thermal stability of starch pastes. DC exhibited marked effects on the viscosity, viscosity thermal stability, adhesion to fiber, properties of starch film and de-sizing behavior, but little effect on the biodegradability. Experiments demonstrated that the cross-linked starch could meet the requirement of warp sizing if the starch was cross-linked to a DC value of 650 AGU/CL by STMP.%为探索适用于淀粉浆料的环保型交联剂,满足经纱上浆中对淀粉浆液黏度热稳定性的要求,替代目前常用的甲醛、环氧氯丙烷等有毒交联剂,以木薯淀粉为原料,无毒的三偏磷酸钠(STMP)为交联剂,通过改变STMP对木薯淀粉的投料比,制备了一系列具有不同交联度(DC)的交联淀粉.研究了交联度对淀粉浆液黏度、黏度热稳定性、黏附性能、浆膜性能、退浆性以及五日生化需氧量(BOD5)和化学需氧量(COD)的影响.结果表明:STMP交联可显著提高淀粉浆料的黏度热稳定性;交联度对淀粉浆液的黏度、黏度热稳定性、黏附性能、浆膜性能及退浆性有显著影响,但对淀粉浆料的生物可降解性影响不大;当采用该交联淀粉用于

  12. Effect of Cassava Flour Characteristics on Properties of Cassava-Wheat-Maize Composite Bread Types

    Directory of Open Access Journals (Sweden)

    Maria Eduardo

    2013-01-01

    Full Text Available Replacement of wheat flour by other kinds of flour in bread making is economically important in South East Africa as wheat is mainly an imported commodity. Cassava is widely available in the region, but bread quality is impaired when large amounts of cassava are used in the bread formulation. Effect of differently processed cassavas (sun-dried, roasted and fermented on composite cassava-wheat-maize bread quality containing cassava levels from 20 to 40% (w/w was evaluated in combination with high-methylated pectin (HM-pectin added at levels of 1 to 3% (w/w according to a full factorial design. Addition of pectin to cassava flour made it possible to bake bread with acceptable bread quality even at concentration as high as 40%. In addition to cassava concentration, the type of cassava flour had the biggest effect on bread quality. With high level of cassava, bread with roasted cassava had a higher volume compared with sun-dried and fermented. The pectin level had a significant effect on improving the volume in high level roasted cassava bread. Crumb firmness similar to wheat bread could be obtained with sun-dried and roasted cassava flours. Roasted cassava bread was the only bread with crust colour similar to wheat bread.

  13. Sensorial evolution of cassava flour (Manihot esculenta crantz) added to protein concentrate cassava leaves.

    Science.gov (United States)

    Lima, Elaine C S; Feijo, Márcia B S; Freitas, Maria C J; Dos Santos, Edna R; Sabaa-Srur, Armando U O; Moura, Luciana S M

    2013-09-01

    Cassava is regarded as the nutritional base of populations in developing countries, and flour, product made of cassava, is the most consumed in the world. The cassava leaves are very rich in vegetable proteins, but a big amount is lost in processing the crop. The objective of this study was to do a sensory evaluation of cassava flour to which a protein concentrate obtained from cassava leaves (CPML) was added. The CPML was obtained from cassava leaves by isoelectric precipitation and added to cassava paste for preparation of flour in three parts 2.5, 5, and 10%. The acceptance test was done by 93 consumers of flour, using hedonic scale of 7 points to evaluate characteristics like color, scent, flavor, bitterness, texture, and overall score. By the method of quantitative descriptive analysis (QDA), eight trained tasters evaluated the following characteristics: whitish color, greenish color, cassava flavor, bitter flavor, characteristic flavor, lumpiness, raw texture, leaf scent, and cassava scent. The acceptability test indicated that flour cassava with 2.5 was preferred. Whitish color, greenish color, cassava flavor, bitter flavor, salty flavor, characteristic flavor, lumpiness texture, raw texture, and the smell of the leaves and cassava flour were the main descriptors defined for flour cassava with CPML has better characteristics.

  14. 载Nisin壳聚糖淀粉复合膜的研制及抑菌效果评价%Preparation and bacteriostasis performance evaluation of chitosan and starch compound film loading Nisin

    Institute of Scientific and Technical Information of China (English)

    李迪; 侯丽娟; 孙庆申; 于艳梅; 韩德权; 杜易阳; 张颍; 王美青; 王汝; 张雅琼

    2012-01-01

    The Nisin-loaded edible films with antibacterial features were prepared using chitosan and starch as film-formers. The structural features and bacterial-static capabilities of the films were characterized and evaluated. The scanning electrical microsopy (SEM) results showed that there were some compatibilities in the Nisin-loaded chitosan/starch compound films. However, the tensile strength of the Nisin-loaded films was lower than that of the blank films. The Nisin-loaded chitosan/starch films showed bacterial-static effects against both Esckerichia coli and Staphylococcus areas. This study provides a theoretical basis for developing safe, biodegradable materials used for food refreshing.%以壳聚糖和淀粉为主要成膜材料,通过向其中添加乳酸链球菌素(Nisin)制备可食性抗菌薄膜,并对膜的结构和抗菌性能进行了评价.载Nisin的壳聚糖淀粉复合膜表面及截面的扫描电镜结果显示,Nisin与膜液有一定的相容性,但是Nisin的添加不同程度地降低了壳聚糖淀粉膜的抗拉强度.载Nisin壳聚糖淀粉膜对细菌中的大肠杆菌和金黄色葡萄球菌均有不同程度的抑制作用.该研究为开发安全、可降解的食品保鲜材料提供一定的理论基础.

  15. Effect of spatial distribution of wax and PEG-isocyanate on the morphology and hydrophobicity of starch films.

    Science.gov (United States)

    Muscat, Delina; Adhikari, Raju; Tobin, Mark J; McKnight, Stafford; Wakeling, Lara; Adhikari, Benu

    2014-10-13

    This study proposes a novel method for improving surface hydrophobicity of glycerol plasticized high amylose (HAG) films. We used polyethylene glycol isocyanate (PEG-iso) crosslinker to link HAG and three natural waxes (beeswax, candelilla wax and carnauba wax) to produce HAG+wax+PEG-iso films. The spatial distributions of wax and PEG-iso across the thickness of these films were determined using Synchrotron-based Fourier transform infrared spectroscopy. The hydrophobicity and surface morphology of the films were determined using contact angle (CA) and scanning electron microscopic measurements, respectively. The distribution patterns of wax and the PEG-iso across the thickness of the film, and the nature of crystalline patterns formed on the surface of these films were found to be the key factors affecting surface hydrophobicity. The highest hydrophobicity (CA >90°) was created when the PEG-iso was primarily distributed in the interior of the films and a hierarchical circular pinnacle structure of solidified wax was formed on the surface.

  16. RESPONSE OF NIGERIAN CASSAVA EXPANSION INITIATIVES TO CLIMATE CHANGES, ECONOMIC GROWTH AND SOME POLICY INSTRUMENT (1970-2012

    Directory of Open Access Journals (Sweden)

    Onwumere Joseph

    2013-10-01

    Full Text Available This study considered the limiting response of Nigeria cassava expansion initiative to climate changes, economic growth and some policy instruments. The presidential initiative to make cassava a foreign exchange earner as well as ensuring that national demand are satisfied has made cassava a significant economic crop and resource input of industrial and international status. Currently, its derivatives such as animal feed, starch, ethanol, cassava chip, cassava flour, cassava liquor etc are in high demand. Having gained international recognition some factors need be examined to ascertain the limiting response of this economic crop some exogenous factors. The specific objectives of interest were to ascertain the response of cassava output expansion to rainfall, temperature, imports, exports, credit allocation to agribusiness, exchange rate, nominal interest rate, inflation and GDP from 1970 – 2012. Also, it examined the short and long run effects of these variables to cassava output so as to know how much adjustment it makes to reach the equilibrium. Secondary data were used for this research work. The technique of data analysis was auto- regressive modeling regression. To capture the long run and short run dynamics of cassava output behavior, the error correction model (ECM using the Engle-Granger methodology was adopted. The result revealed a very high rate of adjustment to long run equilibrium and the variables are correlated which means that impact of each variable on cassava output behavior in the economy is inseparable. The Error correction coefficient of -0.975 measures the speed of adjustment towards long run equilibrium earned the expected negative sign and is statistically significant at 1% risk level. Thus, this study recommends that the emerging cassava economy of Nigeria would be adequately empowered for efficient productivity if the Government stipulate policies that will encourage domestic output expansion to meet the national and

  17. Cassava virus diseases: biology, epidemiology, and management.

    Science.gov (United States)

    Legg, James P; Lava Kumar, P; Makeshkumar, T; Tripathi, Leena; Ferguson, Morag; Kanju, Edward; Ntawuruhunga, Pheneas; Cuellar, Wilmer

    2015-01-01

    Cassava (Manihot esculenta Crantz.) is the most important vegetatively propagated food staple in Africa and a prominent industrial crop in Latin America and Asia. Its vegetative propagation through stem cuttings has many advantages, but deleteriously it means that pathogens are passed from one generation to the next and can easily accumulate, threatening cassava production. Cassava-growing continents are characterized by specific suites of viruses that affect cassava and pose particular threats. Of major concern, causing large and increasing economic impact in Africa and Asia are the cassava mosaic geminiviruses that cause cassava mosaic disease in Africa and Asia and cassava brown streak viruses causing cassava brown streak disease in Africa. Latin America, the center of origin and domestication of the crop, hosts a diverse set of virus species, of which the most economically important give rise to cassava frog skin disease syndrome. Here, we review current knowledge on the biology, epidemiology, and control of the most economically important groups of viruses in relation to both farming and cultural practices. Components of virus control strategies examined include: diagnostics and surveillance, prevention and control of infection using phytosanitation, and control of disease through the breeding and promotion of varieties that inhibit virus replication and/or movement. We highlight areas that need further research attention and conclude by examining the likely future global outlook for virus disease management in cassava.

  18. EXPLORING OPTIMAL FEED TO MICROBES RATIO FOR ANAEROBIC ACIDOGENIC FERMENTATION OF CASSAVA RESIDUE FROM BREWERY

    Directory of Open Access Journals (Sweden)

    Xinying Wang,

    2012-01-01

    Full Text Available Cassava residue from breweries is being generated in large amounts in Guangxi Province of China, and this has potential to cause serious environmental problems if disposed of improperly. Two-stage anaerobic fermentation is a promising method for the treatment of such residue. In this study, the effect of feed to microbes ratio (F/M ratio on the anaerobic acidogenic fermentation of cassava residue was studied to determine the optimal F/M ratio and to maximize the performance in a subsequent methanogenic stage. The experiments were carried out at the F/M ratios of 0.2, 0.61, 1.02, 2.05, 3.07, and 4.09 g cassava-TS/g sludge-VSS in six laboratory-scale, completely stirred, tank reactors (CSTR at mesophilic temperature (35°C. An F/M ratio of 1.02 g cassava-TS/g sludge-VSS resulted in the highest solid removal efficiency and VFA/COD ratio, while starch removal efficiency was still near 100 percent, and acidification was relatively high. As a further benefit, the VFA distribution was more suitable for the subsequent methanogenic fermentation stage.

  19. Bulk H analysis using neutrons for routine quality control of cassava and products

    Energy Technology Data Exchange (ETDEWEB)

    Jonah, S.A., E-mail: jonahsa2001@yahoo.co [Centre for Energy Research and Training, Ahmadu Bello University, Zaria (Nigeria); Okunade, I.O. [Centre for Energy Research and Training, Ahmadu Bello University, Zaria (Nigeria); Abolude, O. [Department of Physics, Ahmadu Bello University, Zaria (Nigeria); Onyike, E.; Inuwa, I.M. [Department of Biochemistry, Ahmadu Bello University, Zaria (Nigeria)

    2011-07-15

    Nuclear and related techniques are useful in addressing the issues of food security and safety facing the world today, via quality control of raw materials and products. In this work, experimental investigations were performed to assess the use of total hydrogen content in cassava and products as a quality control indicator of starch and cyanide contents. The work was carried out using a neutron reflection facility at the Centre for Energy Research and Training, Ahmadu Bello University, Zaria, Nigeria. Cassava samples and products were obtained from retail outlets of Ibadan, Umudike and Zaria, representing three major regions of Nigeria. In general, data obtained indicate a total hydrogen content range of 4.47{+-}0.11-10.71{+-}0.27 wt% for the various samples, including raw, dry and processed cassava. Results show that samples having low hydrogen content are generally rich in cyanide compounds and demonstrate an inverse relationship between hydrogen content and cyanide content. The implication of this is that the neutron reflection facility can be used as a quality control setup for routine determination of hydrogen as an indicator of the cyanide content in cassava and products.

  20. Study on performance increasing of corn starch composite film by pullulanase%用普鲁兰酶改进玉米淀粉基复合膜性能的研究

    Institute of Scientific and Technical Information of China (English)

    陈光; 王香琪; 孙旸; 刘洁心; 徐杨

    2011-01-01

    以玉米淀粉为原料,选用甘油为增塑剂,羧甲基纤维素钠与海藻酸钠复合为增强剂,采用延流法制备玉米淀粉基复合膜.研究增塑剂的种类、用量,增强剂的种类、用量,烘干温度,延流体积等对复合膜性能的影响.普鲁兰酶可使淀粉中的支链淀粉脱支而形成直链淀粉,从而提高淀粉膜的性能.利用正交实验法,以玉米淀粉基复合膜的抗拉强度为指标,研究得出普鲁兰酶对复合玉米淀粉脱支作用时的最佳工艺条件为:酶用量0.8ASPU/g,pH4.5,时间4h,温度60℃.%With corn starch as experimental material,glycerol as plasticizer,sodium carboxy methyl cellulose and sodium alginate composite for strengthening agent,using delay flow for corn starch composite membrane. Both plasticizer and reinforcing agent's types, usages, drying temperature, flow volume etc to the effectiveness of composite membrane's capability were studied.Pullulanase was used to cleave the branching point of amylopectin for preparing starch film.Using the orthogonal trials and measuring tensile strength with corn starch composite film, it was found that the best condition for pullulanase to degrease corn starch was that pullulanase 0.8ASPU/g, pH4.5 ,time 4h,temperature 60℃.

  1. The role of ascorbate peroxidase, guaiacol peroxidase, and polysaccharides in cassava (Manihot esculenta Crantz) roots under postharvest physiological deterioration.

    Science.gov (United States)

    Uarrota, Virgílio Gavicho; Moresco, Rodolfo; Schmidt, Eder Carlos; Bouzon, Zenilda Laurita; Nunes, Eduardo da Costa; Neubert, Enilto de Oliveira; Peruch, Luiz Augusto Martins; Rocha, Miguel; Maraschin, Marcelo

    2016-04-15

    This study aimed to investigate the role of ascorbate peroxidase (APX), guaiacol peroxidase (GPX), polysaccharides, and protein contents associated with the early events of postharvest physiological deterioration (PPD) in cassava roots. Increases in APX and GPX activity, as well as total protein contents occurred from 3 to 5 days of storage and were correlated with the delay of PPD. Cassava samples stained with Periodic Acid-Schiff (PAS) highlighted the presence of starch and cellulose. Degradation of starch granules during PPD was also detected. Slight metachromatic reaction with toluidine blue is indicative of increasing of acidic polysaccharides and may play an important role in PPD delay. Principal component analysis (PCA) classified samples according to their levels of enzymatic activity based on the decision tree model which showed GPX and total protein amounts to be correlated with PPD. The Oriental (ORI) cultivar was more susceptible to PPD.

  2. Substituição do milho pelo resíduo de fecularia de mandioca sobre o desempenho, digestibilidade e características de carcaça de novilhos confinados - DOI: 10.4025/actascianimsci.v31i4.6093 Replacing corn with cassava starch by-products on the performance, digestibility and carcass characteristics of bulls in confinement - DOI: 10.4025/actascianimsci.v31i4.6093

    Directory of Open Access Journals (Sweden)

    Maribel Velandia Valero

    2009-10-01

    Full Text Available O efeito de substituição do milho pelo resíduo desidratado de fecularia de mandioca (0; 12,5; 22,8 e 32,7% foi avaliado sobre o desempenho, a digestibilidade e características de carcaça e 32 bovinos mestiços (½ Nelore x ½ Angus de aproximadamente 18 meses de idade e 380 kg de peso vivo. O delineamento experimental foi o inteiramente casualizado, com quatro tratamentos e oito repetições. Foram analisados o ganho médio diário (GMD, rendimento de carcaça (RC, espessura de gordura de cobertura (EGC, área de olho de lombo (AOL, comprimento de perna (CP, espessura de coxão (EC, ingestão de matéria seca (IMS, conversão alimentar (CA, digestibilidade total aparente da matéria seca (DAMS, matéria orgânica (DAMO, proteína bruta (DAPB, energia bruta (DAEB, fibra em detergente ácido (DAFDA e fibra em detergente neutro (DAFDN. O experimento foi desenvolvido durante um período de 56 dias, após 14 dias de adaptação. Os resultados de GMD, RC, CA, EGC, AOL, CP e EC não apresentaram diferenças (p > 0,05 entre os tratamentos. A IMS apresentou redução linear quando o milho foi substituído pelo resíduo desidratado de fecularia de mandioca. Os coeficientes de digestibilidade da MS, MO, PB, EB, FDN e FDA não variaram entre as rações experimentais.The effects of replacing corn with different levels of cassava starch by-products (0, 12.5, 22.8, and 32.7% were evaluated on performance, digestibility and carcass traits of feedlot bulls. Thirty-two crossbred bulls (½ Nelore x ½ Angus around 18 months of age and 380 kg of body weight were used. A completely randomized design was used, with 4 treatments and 8 replicates. Evaluated traits were: average daily gain (ADG, carcass dressing (CD, backfat thickness (BT, Longissimus area (LDA, leg length (LL and cushion thickness (CT, dry matter intake (DMI, feed conversion ratio (FCR, total apparent digestibility of dry matter (DMDC, organic matter (OMDC, crude protein (CPDC, crude energy (CEDC

  3. Biogas Production Using Anaerobic Biodigester from Cassava Starch Effluent

    OpenAIRE

    Sunarso, S.; B Budiyono; Siswo Sumardiono

    2010-01-01

    IKMs’ factory activity in Margoyoso produces liquid and solid wastes. The possible alternative was to use the liquid effluent as biogas raw material. This study focuses on the used of urea, ruminant, yeast, microalgae, the treatment of gelled and ungelled feed for biogas production, pH control during biogas production using buffer Na2CO3, and feeding management in the semi-continuous process of biogas production that perform at ambient temperature for 30 days. Ruminant bacteria, yeast, urea, ...

  4. Stability of cassava flour-based food bars

    Directory of Open Access Journals (Sweden)

    Erica Caroline da Silva

    2013-03-01

    Full Text Available The consumption of Brazilian cassava has been reduced due to a lack of adjustment to the modern lifestyle. To reverse this trend, new products could be developed specifically targeted to high-value niche markets. Cereal bars stand out as fast food high in nutritional value. A bar formula mimicking cereal bars was prepared using a mixture of Brazilian cassava flour, hydrogenated vegetable fat, dried bananas, ground cashew nuts, and glucose syrup. After being pressed, the bars were dried for 1 hour at 65 °C, packaged in films, and stored under ambient conditions. Its stability was continuously monitored for 210 days in order to ensure its safety and enable its introduction to the market. Texture loss was observed in the packed bars after 90 days of storage, but the sensory characteristics allowed the testers to perceive this tendency after only 30 days of storage. However, chemical, physical, and microbial analyses confirmed that the bars were safe for consumption for 180 days. The results showed that a 45 g cassava flour-based bar enriched with nuts and dried fruits can meet 6% of the recommended daily fiber intake with a caloric value between that of the common cereal bar and that of an energy bar. Adapting the formula with ingredients (fruits, nuts from different regions of Brazil may add value to this traditional product as a fast food.

  5. Determinação da cor, imagem superficial topográfica e ângulo de contato de biofilmes de diferentes fontes de amido Determination of color, topographic superficial image and contact angle of the biofilms of different starch sources

    Directory of Open Access Journals (Sweden)

    Washington Azevêdo da Silva

    2007-02-01

    starch in biofilms. The aim of this work was to study the color variation, the topographic superficial surface by scanning electron microscopy and the water absorption by contact angle of biofilms produced with three different starch sources: potato starch film (PSF, cassava starch film (CSF and maize starch film (MSF with varied concentration: 1, 2 and 3% to prepare biofilms using a complete randomize design with three repetitions. The interaction between starch source and concentration was statistically significant for contact angle whereas it was not significant for color. The color difference was affected by starch source being higher for CSF. As concentration increased in biofilms of potato and cassava, the contact angle decreased in contrast to maize biofilms which remained constant.

  6. Instant blend from cassava derivatives produced by extrusion

    Directory of Open Access Journals (Sweden)

    Fernanda Rossi Moretti Trombini

    2016-03-01

    Full Text Available ABSTRACT: The current research aimed to evaluate the effects of extrusion parameters on the physical characteristics of extruded blends of cassava leaf flour and starch. A factorial central composite design with four independent variables and the response surface methodology were used to evaluate the results of color parameters (L*, a*, b*, water absorption index, water solubility index and paste properties, according to the variations in the leaf flour percentage (1.5 to 7.5%, extrusion temperature (60 to 100ºC, screw speed (175 to 231rpm and moisture (20 to 30%. Extrusion conditions affect color, water absorption and water solubility indexes and paste properties of blends. The intermediate tested conditions of variable parameters lead to obtain extruded products with higher cold viscosity and water absorption index and light color, desirable qualities for rapid preparation products.

  7. Resistance to Sri Lankan Cassava Mosaic Virus (SLCMV) in Genetically Engineered Cassava cv. KU50 through RNA Silencing

    KAUST Repository

    Ntui, Valentine Otang

    2015-04-22

    Cassava ranks fifth among the starch producing crops of the world, its annual bioethanol yield is higher than for any other crop. Cassava cultivar KU50, the most widely grown cultivar for non-food purposes is susceptible to Sri Lankan cassava mosaic virus (SLCMV). The objective of this work was to engineer resistance to SLCMV by RNA interference (RNAi) in order to increase biomass yield, an important aspect for bioethanol production. Here, we produced transgenic KU50 lines expressing dsRNA homologous to the region between the AV2 and AV1 of DNA A of SLCMV. High level expression of dsRNA of SLCMV did not induce any growth abnormality in the transgenic plants. Transgenic lines displayed high levels of resistance to SLCMV compared to the wild-type plants and no virus load could be detected in uninoculated new leaves of the infected resistant lines after PCR amplification and RT-PCR analysis. The agronomic performance of the transgenic lines was unimpaired after inoculation with the virus as the plants presented similar growth when compared to the mock inoculated control plants and revealed no apparent reduction in the amount and weight of tubers produced. We show that the resistance is correlated with post-transcriptional gene silencing because of the production of transgene specific siRNA. The results demonstrate that transgenic lines exhibited high levels of resistance to SLCMV. This resistance coupled with the desirable yield components in the transgenic lines makes them better candidates for exploitation in the production of biomass as well as bioethanol.

  8. Resistance to Sri Lankan cassava mosaic virus (SLCMV in genetically engineered cassava cv. KU50 through RNA silencing.

    Directory of Open Access Journals (Sweden)

    Valentine Otang Ntui

    Full Text Available Cassava ranks fifth among the starch producing crops of the world, its annual bioethanol yield is higher than for any other crop. Cassava cultivar KU50, the most widely grown cultivar for non-food purposes is susceptible to Sri Lankan cassava mosaic virus (SLCMV. The objective of this work was to engineer resistance to SLCMV by RNA interference (RNAi in order to increase biomass yield, an important aspect for bioethanol production. Here, we produced transgenic KU50 lines expressing dsRNA homologous to the region between the AV2 and AV1 of DNA A of SLCMV. High level expression of dsRNA of SLCMV did not induce any growth abnormality in the transgenic plants. Transgenic lines displayed high levels of resistance to SLCMV compared to the wild-type plants and no virus load could be detected in uninoculated new leaves of the infected resistant lines after PCR amplification and RT-PCR analysis. The agronomic performance of the transgenic lines was unimpaired after inoculation with the virus as the plants presented similar growth when compared to the mock inoculated control plants and revealed no apparent reduction in the amount and weight of tubers produced. We show that the resistance is correlated with post-transcriptional gene silencing because of the production of transgene specific siRNA. The results demonstrate that transgenic lines exhibited high levels of resistance to SLCMV. This resistance coupled with the desirable yield components in the transgenic lines makes them better candidates for exploitation in the production of biomass as well as bioethanol.

  9. Resistance to Sri Lankan cassava mosaic virus (SLCMV) in genetically engineered cassava cv. KU50 through RNA silencing.

    Science.gov (United States)

    Ntui, Valentine Otang; Kong, Kynet; Khan, Raham Sher; Igawa, Tomoko; Janavi, Gnanaguru Janaky; Rabindran, Ramalingam; Nakamura, Ikuo; Mii, Masahiro

    2015-01-01

    Cassava ranks fifth among the starch producing crops of the world, its annual bioethanol yield is higher than for any other crop. Cassava cultivar KU50, the most widely grown cultivar for non-food purposes is susceptible to Sri Lankan cassava mosaic virus (SLCMV). The objective of this work was to engineer resistance to SLCMV by RNA interference (RNAi) in order to increase biomass yield, an important aspect for bioethanol production. Here, we produced transgenic KU50 lines expressing dsRNA homologous to the region between the AV2 and AV1 of DNA A of SLCMV. High level expression of dsRNA of SLCMV did not induce any growth abnormality in the transgenic plants. Transgenic lines displayed high levels of resistance to SLCMV compared to the wild-type plants and no virus load could be detected in uninoculated new leaves of the infected resistant lines after PCR amplification and RT-PCR analysis. The agronomic performance of the transgenic lines was unimpaired after inoculation with the virus as the plants presented similar growth when compared to the mock inoculated control plants and revealed no apparent reduction in the amount and weight of tubers produced. We show that the resistance is correlated with post-transcriptional gene silencing because of the production of transgene specific siRNA. The results demonstrate that transgenic lines exhibited high levels of resistance to SLCMV. This resistance coupled with the desirable yield components in the transgenic lines makes them better candidates for exploitation in the production of biomass as well as bioethanol.

  10. The effects of glycerol and guar-xanthan mixture on mechanical and barrier properties of starch based edible films - chemometric analysis

    Directory of Open Access Journals (Sweden)

    Šuput Danijela Z.

    2016-01-01

    Full Text Available The aim of this work was to evaluate the simultaneous effect of glycerol (30%, 40%, 50% and guar-xanthan gum addition (0.1%, 0.3%, 0.5% effect on starch based edible film mechanical and barrier properties. According to Response Surface Methodology, the most influential parameter in the second order polynomial models calculation was the percentage of glycerol, while the linear term of guar-xanthan content was important only for second order polynomial model calculation for tensile strength and water vapor permeability. According to Principal Component Analysis, samples grouping along the first component are primarily due to the content of glycerol, which is also confirmed by ANOVA analysis. According Cluster Analysis, two separate clusters are observed on the dendrogram, which includes the right (with the increased value of tensile strength and the left cluster (with the increased value of elongation break and water vapor permeability. The observed distance the two clusters is considerable (approx. 80. [Projekat Ministarstva nauke Republike Srbije, br. TR-31055: Osmotic dehydration of food - energy and environmental aspects of sustainable production

  11. 不同淀粉对速冻卡通鸡块的品质影响研究%Study on effect of different starch on quality of quick-frozen cartoon chicken

    Institute of Scientific and Technical Information of China (English)

    王杨; 刘欣; 张萍

    2015-01-01

    以速冻卡通鸡块为研究对象,通过对比相同添加量的玉米淀粉、豌豆淀粉、马铃薯淀粉和木薯淀粉在对鸡块品质的影响发现:添加四种淀粉的产品在色泽、滋气味、手感和口感方面差异性不显著;在改善鸡块的弹性方面,木薯淀粉和马铃薯淀粉显著优于豌豆淀粉与玉米淀粉,其中木薯淀粉效果最好。%Quick-frozen cartoon chicken was taken as an object of study. The effects of different addition of the corn starch, pea starch, potato starch and cassava starch on the quality of chicken nuggets were compared. The results showed that there was no significant difference in color, smell, feel and taste of the products added with the four kinds of starches respectively. In the aspect of improving the elasticity of the chicken nuggets, cassava starch and potato starch were obviously better than the pea starch and corn starch. Among them the effect of cassava starch was best.

  12. Karakteristik Edible Film Pati Sagu Alami dan Pati Sagu Fosfat dengan Penambahan Gliserol (Characteristics of Edible Film from Native and Phosphate Sago Starches with the Addition of Glycerol

    Directory of Open Access Journals (Sweden)

    Febby Jeanry Polnaya

    2016-12-01

    Tujuan penelitian ini adalah untuk mempelajari pengaruh penambahan beberapa konsentrasi gliserol pada pembuatan edible film dari pati sagu alami dan pati sagu fosfat terhadap sifat fisik, mekanik dan barrier film. Rancangan yang digunakan adalah rancangan acak lengkap yang terdiri dari dua faktor yaitu perlakuan jenis pati sagu dengan dua taraf perlakuan yaitu: pati sagu alami dan pati sagu fosfat dan tiga taraf konsentrasi gliserol yaitu: 0,5, 1,0 dan 1,5 % (b/b. Peubah yang diamati adalah tensile strength¸ elongasi, daya larut, transparansi, dan laju transmisi uap air. Karakteristik edible film yang dihasilkan meliputi tensile strength adalah 3,05 - 31,49 MPa, elongasi 3,03 - 20,94 %, daya larut 33,44 - 42,43 %, transparansi 0,59 - 4,14 %, dan laju transmisi uap air 7,76 - 15,80 g/m2.jam. Penambahan gliserol menyebabkan elongasi, daya larut, dan laju transmisi uap air meningkat, tetapi tensile strength dan transparansinya menurun. Perlakuan pati sagu fosfat hanya menyebabkan daya larut film meningkat, tetapi tidak untuk sifat-sifat film lainnya. Kata kunci: Edible film; gliserol; pati sagu alami; pati sagu fosfat

  13. Culture conditions for yellow pigment formation byMonascus sp. KB 10 grown on cassava medium.

    Science.gov (United States)

    Yongsmith, B; Tabloka, W; Yongmanitchai, W; Bavavoda, R

    1993-01-01

    An isolate ofMonascus, from a commercial, fermented soybean curd (sufu) was grown on a cassava medium. With medium at an initial pH of 7.0 an orange-red pigmentation was produced but with an initial pH below 4, a light golden pigment was obtained. A medium containing, w/v, 3% cassava starch, 0.4% peptone and 0.1% glutamic acid, with an initial pH of 2.5 was optimal for the production of this yellow pigment, which had a single maximum absorption spectrum at 330 nm. The spectroscopic characterization of the purified yellow pigments demonstrated a monascin-ankaflavin-monascorubrin skeleton.

  14. CAMPURAN PULP TANDAN KOSONG KELAPA SAWIT DAN SELULOSA MIKROBIAL NATA DE CASSAVA DALAM PEMBUATAN KERTAS

    Directory of Open Access Journals (Sweden)

    Khaswar Syamsu

    2014-04-01

    Full Text Available Nowadays, forest-extracted wood cellulose still predominantly serves as raw material for pulp and paper manufacture in Indonesia. Consequently, the deforestation rate has alarmingly increased. The purpose of this research is to study the use of mixed microbial cellulose pulp from nata de cassava and pulp from empty oil palm fruit bunch (EOPFB for paper manufacture. In this research, pulp of nata de cassava’s microbial cellulose was mixed with EOPFB pulp at various proportions. Additives (i.e. 2% alum, 2.5% tapioca starch, and 5% kaolin were added to such mixture. Sheet forming without additives was made as a control. Addition of microbial cellulose tends to increase the physical and strength properties of paper and decrease the capability to absorb water significantly. The mixture of pulp of empty oil palm fruit bunch and microbial cellulose from nata de cassava has a potency to substitute wood pulp for paper manufacture.

  15. Resistant starches.

    Science.gov (United States)

    Jenkins, D J; Kendall, C W

    2000-03-01

    Initially, it was hoped that resistant starches (ie, starches that enter the colon) would have clear advantages in the reduction of colon cancer risk and possibly the treatment of ulcerative colitis. Recent studies have confirmed the ability of resistant starch to increase fecal bulk, to increase the molar ratio of butyrate in relation to other short-chain fatty acids, and to dilute fecal bile acids. However, reduction in fecal ammonia, phenols, and N-nitroso compounds have not been achieved. At this point the picture from the standpoint of colon cancer risk reduction is not clear. Nevertheless, there is a fraction of what has been termed resistant starch (RS1), which enters the colon and acts as slowly digested, or lente, carbohydrate. Foods in this class are low glycemic index and have been shown to reduce the risk of chronic disease. They have been associated with systemic physiologic effects such as reduced postprandial insulin levels and higher high-density lipoprotein cholesterol levels. Consumption of low glycemic index foods has been shown to be related to a reduced risk of type 2 diabetes. Type 2 diabetes has in turn been related to a higher risk of colon cancer, especially colon cancer deaths. If carbohydrate has a protective role in colon cancer prevention, it may lie in the systemic effects of low glycemic index foods. The colonic advantages of different carbohydrates, therefore, remain to be documented. However, there is reason for optimism about the possible health advantages of so-called resistant starches that are slowly digested in the small intestine.

  16. Effect of coating preservation on storage quality of edible fresh cassava%涂膜保鲜对食用鲜木薯品质的影响

    Institute of Scientific and Technical Information of China (English)

    谢江; 查春月; 刘婷; 邓小顺; 古碧; 林莹

    2012-01-01

    In order to improve the quality of fresh cassava during stor age . the preservation effect of fresh cassavas, which was respectively coated with sodium alginate, chitosan, licjuid paraffin, was studied at normal atmospheric temperature. The moisture content, starch con-lent, reducing sugar content, respiration intensity- weight loss rate and decay rate of the fresh cassava were discussed during cassava storage. The results showed that, compared with control group, three kinds of coating pretreatment could reduce changes of quality of fresh cassava during storage at normal atmospheric temperature. A mo rig three kinds of coating pretrcatment, the liquid paraffin coating had the best effect for fresh-keeping of cassava. It could ohviousty inhibit the respiration, water loss, starch hydrolysis and reducing sugar produclion and reduce weight loss rate and decay rate of fresh cassava.%为了提高食用鲜木薯在贮藏期间的质量,研究海藻酸钠、壳聚糖和液体石蜡涂膜剂处理对鲜木薯常温下的贮藏保鲜效果的影响,探讨鲜木薯在贮藏过程中水分含量、淀粉含量、还原糖含量、呼吸强度、失重率和腐烂率的变化规律.结果表明:在常温条件下,和空白组相比3种涂膜剂均能减缓鲜木薯在贮藏期间的品质变化.3种涂膜剂中,液体石蜡的保鲜效果最佳,能明显抑制鲜木薯呼吸作用、水分的散失、淀粉的水解和还原糖的产生,减缓鲜木薯失重和腐烂.

  17. Quality evaluation of stiff porridges prepared from Irish potato (Solanum tuberosum) and pigeon pea (Cajanus cajan) starch blends.

    Science.gov (United States)

    Abu, Joseph Oneh; Enyinnaya, Chinma Chiemela; James, Samaila; Okeleke, Ezinne

    2012-06-01

    Quality attributes of stiff porridges prepared from Irish potato and pigeon pea starch blends were studied. Starches were extracted from Irish potato and pigeon pea using a wet extraction method. Various ratios of the starches were mixed and analyzed for chemical, functional and pasting properties. The starch blends were then prepared into stiff porridges for sensory evaluation using a 20-man sensory panel. Substitution of Irish potato starch with pigeon pea starch led to increases in protein (0.15 to 1.2%), fat (0.26 to 0.56%) and ash (0.30 to 0.69%) while the amylose content of the starch blends decreased (from 23.8 to 18.4%) respectively. Functional properties such as bulk density (0.75 to 0.60 g/cm(3)), water absorption capacity (3.1 to 2.6 g water/ g sample) and dispersibility (58.6 to 42.7%) decreased significantly (P stiff porridges were not adversely affected by pigeon pea starch inclusion. Therefore it should be possible to incorporate up to 50% of low digestible pigeon pea starch into Irish potato starch from legumes such as pigeon pea as alternatives to cassava starch in the preparation of stiff porridges. Such porridges made from Irish potato and legume starches could provide additional incentive for individuals requiring decreased and or slow starch digestibility such as diabetics.

  18. Development and utilization of cassava residue as feed resource%木薯渣作为饲料资源的开发与利用

    Institute of Scientific and Technical Information of China (English)

    黄萍; 齐仁立

    2012-01-01

    木薯渣是木薯加工过程中产生的下脚料,富含大量盼纤维和淀粉。近年来,木薯渣作为饲料资源进行开发和利用能够使其变废为宝。减少对环境的破坏,受到了国内外的普遍重视。其中微生物发酵处理能够使木薯渣的粗纤维降解,改善适口性,提高饲料转化率。本文就木薯渣的营养特点、加工处理和在畜禽养殖中的应用等作一概括和总结。%Cassava residue is the remainder of cassava starch. In recent years, cassava residue has been applied as utilization can increase the economic value of cassava residue The microbial fermentation is an ideal process to degradate processing, which the feed resource has rich fiber and for development. Its and reduce the damage to environment. the crude fiber in cassava residue and improve palatability as well as the feed conversion rate. This paper summarized the nutrition characteristic, the processing and the application in livestock and poultry of cassava residue

  19. Gluten-free dough-making of specialty breads: Significance of blended starches, flours and additives on dough behaviour.

    Science.gov (United States)

    Collar, Concha; Conte, Paola; Fadda, Costantino; Piga, Antonio

    2015-10-01

    The capability of different gluten-free (GF) basic formulations made of flour (rice, amaranth and chickpea) and starch (corn and cassava) blends, to make machinable and viscoelastic GF-doughs in absence/presence of single hydrocolloids (guar gum, locust bean and psyllium fibre), proteins (milk and egg white) and surfactants (neutral, anionic and vegetable oil) have been investigated. Macroscopic (high deformation) and macromolecular (small deformation) mechanical, viscometric (gelatinization, pasting, gelling) and thermal (gelatinization, melting, retrogradation) approaches were performed on the different matrices in order to (a) identify similarities and differences in GF-doughs in terms of a small number of rheological and thermal analytical parameters according to the formulations and (b) to assess single and interactive effects of basic ingredients and additives on GF-dough performance to achieve GF-flat breads. Larger values for the static and dynamic mechanical characteristics and higher viscometric profiles during both cooking and cooling corresponded to doughs formulated with guar gum and Psyllium fibre added to rice flour/starch and rice flour/corn starch/chickpea flour, while surfactant- and protein-formulated GF-doughs added to rice flour/starch/amaranth flour based GF-doughs exhibited intermediate and lower values for the mechanical parameters and poorer viscometric profiles. In addition, additive-free formulations exhibited higher values for the temperature of both gelatinization and retrogradation and lower enthalpies for the thermal transitions. Single addition of 10% of either chickpea flour or amaranth flour to rice flour/starch blends provided a large GF-dough hardening effect in presence of corn starch and an intermediate effect in presence of cassava starch (chickpea), and an intermediate reinforcement of GF-dough regardless the source of starch (amaranth). At macromolecular level, both chickpea and amaranth flours, singly added, determined

  20. Cultivation of oyster mushrooms on cassava waste

    NARCIS (Netherlands)

    Sonnenberg, A.S.M.; Baars, J.J.P.; Obodai, M.; Asagbra, A.

    2015-01-01

    Cassava is a major food crop for approximately 700 million people, especially in African countries. A large quantity of waste is produced during processing of cassava, mainly consisting of tuber peels. Although previous research has shown that these peels can be an ingredient for substrate to cultiv

  1. Amphoteric Starch in Simultaneous Process Preparation with Box-Behnken Design for Optimal Conditions

    Directory of Open Access Journals (Sweden)

    Sopa Cansee

    2008-01-01

    Full Text Available Cassava starch was chemically modified to produce an amphoteric starch. The amphoteric starch was prepared in a simultaneous process which was evaluated in relation to four factors: temperature (45-55 °C, 3-chloro-2-hydroxypropyltrimethylammonium chloride (CHPTAC, 4-12% and sodium tripolyphosphate (STP, 2-8% concentrations, and reaction time (2-6 h. The extent of amphoteric starch produced was determined by the degree of substitution (DS of the nitrogen content and percentage of phosphorus content. In addition, a quantitative response of yield and whiteness as well as pasting characteristics were tested. Response surface analysis showed that the DS (0.01-0.05 increased with increasing temperature, CHPTAC and reaction time. The phosphorus content (0.09-0.34% followed a parabolic shape with all of the factors. Consequently, the response surface methodology appears to be a powerful technique to determine the optimal conditions for the production of amphoteric starches.

  2. 黄姜渣提取淀粉的成分及颗粒结构分析%Analysis on the Composition and Structure of Starch Granules from Dioscorea zingibrensis

    Institute of Scientific and Technical Information of China (English)

    杨铖; 毛楠; 籍国东

    2011-01-01

    [Objective] The aim was to analyze the the composition and structure of starch granules from Dioscorea zingiberensis. [Method] High-quality Dioscorea zingiberensis starch was extracted from the residues of yellow ginger diosgenin processing by physical separation technology,and then the composition and structure of starch granules from Dioscorea zingiberensis was analyzed. [ Result ] The water content of Dioscorea zingiberensis starch was close to that of cassava starch; its starch purity was similar to those of cassava starch and potato starch in the market;its protein content was lower than that of cassava starch and potato starch,and lipid content was lower than that of potato starch, while its amylose content was higher than those of cassava starch and potato starch. So Dioscorea zingiberensis starch had better quality than cassava starch and potato starch. Dioscorea zingiberensis starch granules were caky ,had rough surface,larger and uniform sizes,and granules diameters were 15 -25 μm. Acid hydrolysis showed that the granule may be a hollow structure ,and the hollows alternately distributed in the crystalline region and amorphous region of the granule. [ Conclusion]The research provides reference for the application of Dioscorea zingiberensis in food industry.%[目的]分析黄姜渣提取淀粉的成分及颗粒结构.[方法]利用物理分离方法从黄姜生产皂素的废渣中提取优质黄姜淀粉,分析了其主要成分和颗粒结构.[结果]黄姜淀粉的含水量与木薯淀粉接近;其淀粉含量与木薯淀粉和马铃薯淀粉接近;其蛋白质含量低于其他2种淀粉;其脂肪含量低于马铃薯淀粉;其直链淀粉含量则高于其他2种淀粉,品质更优.SEM分析表明,黄姜淀粉颗粒呈饼状,表面较粗糙,颗粒较大且较均匀,粒径在15~25 μm.酸水解分析表明,黄姜淀粉颗粒可能为中空的,且在颗粒内部结晶区和无定形区是交替分布的.[结论]该研究为黄姜淀粉在食品行业的应用提供了参考.

  3. Hidrofilicidade de filmes de amido/poli(butileno adipato co-tereftalato (Pbat adicionados de tween 80 e óleo de soja Hydrophilicity of starch and poly(butylene adipate-co-terephthalate (Pbat films containing tween 80 and soybean oil

    Directory of Open Access Journals (Sweden)

    Renata P. Herrera Brandelero

    2013-01-01

    Full Text Available A incorporação de amido ao polímero poli (butilenoadipatoco-tereftalato (PBAT através de blendas com alto teor de amido pode ser uma alternativa para obter embalagens biodegradáveis, minimizar custos e o uso de recursos não renováveis. No entanto, a adição de amido aumenta a permeabilidade ao vapor de água (PVA. A incorporação em filmes com amido de substâncias como óleos vegetais e surfactantes pode diminuir a hidrofilicidade, favorecendo as aplicações destes como embalagens. A hidrofilicidade dos filmes elaborados por blendas de amido/PBAT adicionados de óleo de soja (OS e tween 80 (TW foi avaliada considerando o efeito do OS e TW nas isotermas de sorção dos filmes, na PVA e nos coeficientes de difusão (Dw e solubilidade (β do vapor de água. Filmes com OS com ou sem TW apresentaram menor quantidade de água de sorção, sendo os filmes com menores quantidades de OS e sem TW menos hidrofílicos e menos permeáveis aos vapores de água. A adição de OS reduziu os valores de β e Dw dos filmes de amido/PBAT. O efeito foi relacionado com o aumento das porções hidrofóbicas e da compatibilidade entre o amido e PBAT na presença de OS.Incorporating starch into the poly(butylene adipate-co-terephthalate (PBAT polymer by means of blends with high starch contents is a possible option for producing biodegradable packaging using renewable resources and reducing costs. However, the addition of starch increases the water vapour permeability (WVP. The incorporation of substances as lipids and surfactants can reduce the hydrophilicity of films containing starch, favouring their use as packaging. The hydrophilicity of films produced from blends of starch/PBAT with added soybean oil (SO and tween 80 (TW was studied. The effects of these substances on the sorption isotherm, on the WVP and on the water vapour diffusion (Dw and solubility (β coefficients of the films were evaluated. The water sorption in films with SO, with or without TW

  4. Effect of Plasticizers on Physical and Mechanical Properties of Potato Starch- based Composite Films%增塑剂对马铃薯淀粉基复合膜物理机械性能的影响

    Institute of Scientific and Technical Information of China (English)

    贾超; 王利强; 卢立新; 赵艺程

    2012-01-01

    Potato starch based composite films were prepared by casting using potato starch, pullulan, gelatin as film forming material, calcium chloride as cross-linking agent, and glycerol, sorbitol, and polyethylene glycol as plasticizer. The effects of three kinds of plasticizers on physical and mechanical properties of composite films were studied. The results showed that tensile strength and Young's modulus of the composite films decrease significantly with plasticizer contents; elongation increases significantly with glycerol and sorbitol contents; effect of polyethylene glycol on elongation is not obvious; water vapor permeability and water solubility of composite films increase with plasticizer contents; polyethylene glycol can reduce the light transmission rate of the composite films significantly.%以马铃薯淀粉、普鲁兰多糖、明胶为成膜物质,氯化钙为交联剂,甘油、山梨醇、聚乙二醇为增塑剂,采用流延法制备了马铃薯淀粉基复合膜,研究了3种增塑剂对复合膜物理机械性能的影响。结果表明:复合膜的抗拉强度和弹性模量均随增塑剂含量的增加而显著减小,断裂伸长率随甘油和山梨醇含量的增加而显著增加,聚乙二醇对其影响不显著;复合膜的水蒸气透过率和水溶性均随增塑剂含量的增加而增加;聚乙二醇能够显著降低复合膜的透光率。

  5. A novel process for direct production of acetone-butanol-ethanol from native starches using granular starch hydrolyzing enzyme by Clostridium saccharoperbutylacetonicum N1-4.

    Science.gov (United States)

    Thang, Vu Hong; Kobayashi, Genta

    2014-02-01

    In this work, a new approach for acetone-butanol-ethanol (ABE) production has been proposed. Direct fermentation of native starches (uncooked process) was investigated by using granular starch hydrolyzing enzyme (GSHE) and Clostridium saccharoperbutylacetonicum N1-4. Even the process was carried out under suboptimal condition for activity of GSHE, the production of ABE was similar with that observed in conventional process or cooked process in terms of final solvent concentration (21.3 ± 0.4 to 22.4 ± 0.4 g/L), butanol concentration (17.5 ± 0.4 to 17.8 ± 0.3 g/L) and butanol yield (0.33 to 0.37 g/g). The production of solvents was significantly dependent on the source of starches. Among investigated starches, corn starch was more susceptible to GSHE while cassava starch was the most resistant to this enzyme. Fermentation using native corn starch resulted in the solvent productivity of 0.47 g/L h, which was about 15 % higher than that achieved in cooked process. On the contrary, uncooked process using cassava and wheat starch resulted in the solvent productivity of 0.30 and 0.37 g/L h, which were respectively about 30 % lower than those obtained in cooked process. No contamination was observed during all trials even fermentation media were prepared without sterilization. During the fermentation using native starches, no formation of foam is observed. This uncooked process does not require cooking starchy material; therefore, the thermal energy consumption for solvent production would remarkably be reduced in comparison with cooked process.

  6. 增塑剂甘油对甘薯淀粉膜性能的影响研究%Effect of Glycerol Plasticizer on the Properties of Sweet Potato Starch -Based Films

    Institute of Scientific and Technical Information of China (English)

    刘鹏飞; 孙圣麟; 王文涛; 侯汉学; 董海洲

    2015-01-01

    采用甘油作为增塑剂制备甘薯淀粉膜,研究了甘油/淀粉比对甘薯淀粉膜性能的影响。结果表明:加入甘油后,淀粉糊各特征点黏度值发生不同程度的变化;随着甘油量的增加,膜的断裂伸长率和水蒸气透过率呈递增的趋势,淀粉膜的热封性能逐步得到提高,抗拉强度呈递减的趋势;随着甘油的加入,膜的透光率增大;甘油分子与淀粉分子之间有较弱的作用,在2θ=14.8°处产生了一个新的峰;淀粉颗粒的分散和分布随着甘油的加入有明显改善,淀粉膜表面变得平整;紫外老化试验表明随着甘油量的增加,延缓了淀粉膜的老化作用。当甘油/淀粉比在0.3/1~0.4/1之间时,甘油和淀粉的相容性较好,甘油对淀粉有较好的塑化效果。%Sweet potato starch (SPS)-based films have been prepared with glycerol as plasticizer.The influ-ence of glycerol /starch of different ratios on the films properties has been studied in the paper.The results showed that the glycerol could significantly change SPS pasting characteristics.With the increase of glycerol content,the e-longation at break,as well as the water vapor permeability gradually increased,while the tensile strength gradually decreased.The films exhibited a better heat endurance with the increasing content of glycerol.The addition of glycer-ol could raise the light transmission of films.The glycerol and starch molecules had weaker interaction;a new peak was produced after the addition of glycerol,between the 2 theta,at 14.8°.The dispersion and distribution of the starch granules were improved significantly,and the surface of the films became smooth since adding glycerol.The retrogradation of the films was delayed by the increasing content of the glycerol.These results indicated that the glyc-erol has a good compatibility and rather better plasticizing effect with the starch matrix when the ratios of glycerol /starch

  7. Development of Jackfruit Crackers: Effects of Starch Type and Jackfruit Level

    Directory of Open Access Journals (Sweden)

    Nor Afizah Mustapha

    2015-01-01

    Full Text Available Crackers are one of the convenient and inexpensive snacks that have high market potential.  Most of the commercial crackers are carbohydrate-rich and normally considered as a low value-added product.  In this study, innovative value added crackers made of jackfruit were developed.  The effect of starches (sago and cassava and levels of jackfruit (30 and 50%, w/w on characteristics of the crackers were investigated.  Physicochemical properties of the products at each predetermined processing steps (steaming, drying and frying; bulk density, expansion ratio, color and carotenoid contents were measured.  A decrease in jackfruit level resulted in crackers with lower bulk density (0.26 to 0.41 g/cm3 and higher volume expansion ratio (2.84 to 4.66 cm3.  Blending the cassava and sago starch at 1:1 ratio resulted in lower bulk density and higher expansion ratio compared to crackers made with a single type of starch.  The L* and b* values decreased with drying and frying process, indicative of Maillard reactions.  The higher L* value was influenced by the starch content, while higher jackfruit led increased the b* values, attributed to the presence of pigments in the fruit.  Total carotenoid contents of fried crackers increased following steaming process, ranging from 0.061 to 0.199 mg/100g and samples made with blend of sago and cassava has the highest carotenoid contents.  A jackfruit level of 30% (w/w made with blend of sago and cassava starches (1:1 produced fried crackers with the most acceptable physicochemical characteristics.  Crackers with improved nutritional value can be developed by incorporating jackfruit, thus expanding the conventional use of the fruit.

  8. 改性淀粉/PVA生物降解塑料膜的制备及表征%Preparation and characterization of biodegradable plastic film from modified starch/PVA

    Institute of Scientific and Technical Information of China (English)

    董明; 郝艳玲; 范福海

    2013-01-01

    以氧化改性过后的马铃薯淀粉为原料,经过交联、增塑、增强后,采用流延的方法制备生物降解塑料膜,研究了改性淀粉、丙三醇、甲醛、尿素、聚乙烯醇、反应温度等因素对模力学性能的影响.结果表明,影响膜强度主要因素为丙三醇的含量,其次为甲醛、改性淀粉、尿素的量、反应时间及聚乙烯醇的量.最佳条件为:水100 mL,改性淀粉3.3g,尿素1.0g,聚乙烯醇1.2g,甲醛1.6 mL,丙三醇0.6 mL,反应时间110 min.在此条件下,制得膜的拉伸强度为20.05 MPa,断裂伸长率为65%.%We take oxidation modified potato starch as raw material, after the step of cross linking, plasti-cing and reinforcing, to prepare biodegradable plastic film by the method of continuation flow membrane. Effects of modified starch, glycerol, formaldehyde, urea, polyvinyl alcohol, reaction temperature, and other factors on capability of the plastic film were researched. The results shows that the main factor on effecting film strength is amount of glycerin, secondly, the amount of formaldehyde, modified starch, urea, the reaction time and the amount of polyvinyl alcohol. The optimum conditions were as follows; H2O 100 mL, modified starch 3.3 g, urea 1.0 g, polyvinyl alcohol 1.2 g, formaldehyde 1.6 mL, glycerol 0.6 mL, reaction time is 110 min. Under this condition, the tensile strength of this film is 20.05 MPa, and the elongation at break is 65%.

  9. Study on film mechanical properties and adhesion-to-fibers of APAM/starch blends%APAM/淀粉共混薄膜力学性能及粘合强度的研究

    Institute of Scientific and Technical Information of China (English)

    屈磊; 祝志峰

    2014-01-01

    Amphoteric polyacrylamide( APAM)was synthesized using acrylamide( AM),acrylic acide (AA)and acryloxyethyltrimethyl ammonium chloride(DAC)as copolymeric monomers in aqueous sys-tem. Then,adhesion of APAM/starch blends to cotton and polyester fibers were studied and tensile prop-erties of APAM/starch film were explored. It was found that the incorporation of APAM into starch could significantly improve the adhesion of the blends to the fibers. The adhesion strength increased with the in-crease in proportion of APAM. The incorporation was able to mitigate the brittleness of starch film and produce toughing effect on the film. And it was also helpful to reduce the time required to break in water, raised moisture absorption of the film,and increased its water-swelling power,which was easy to desizing of the blends in textile production.%以丙烯酰胺( AM)、丙烯酸( AA)和丙烯酰氧乙基三甲基氯化铵( DAC)为共聚合单体,通过水溶液聚合合成两性聚丙烯酰胺( APAM),然后探索了它与淀粉的共混比对纤维粘合强度的影响,研究了这种共混物的薄膜性能。研究结果表明,APAM与淀粉共混后能够明显改善对棉和涤纶纤维的粘合强度,随着APAM用量的增加,对棉和涤纶纤维粘合强度逐渐增大;通过与APAM的共混,能够降低淀粉膜的脆性,对淀粉膜具有增韧作用;并能缩短淀粉膜的水溶时间、增加吸湿率和水溶胀率,有利于纺织退浆。

  10. Aroma interactions with starch

    DEFF Research Database (Denmark)

    Jørgensen, Anders Dysted

    Starches are used to enhance aroma perception in low-fat foods. Aroma compounds can bind physically to the starch in grooves on the surface or they can form complexes inside amylose helices. This study has been divided into two parts: one part regarding binding of aromas to starches and their aroma......-release, and another part regarding stimulation of a fungal secretome using different carbohydrates. In the first part, nine aromas and one aroma-mixture were mixed with nine different starches, including genetically modified starches. The objective of this sub-project was to bind aromas to the starches to 15 weight......-percent. Aroma binding was tested on both amorphous starches and on native starch granules. A series of aldehydes and alcohols were also tested for binding to the starches. The aromas with the highest volatility were positively retained by starch, whereas for aromas with a lower volatility the starch had...

  11. Biodegradable starch-based polymeric materials

    Science.gov (United States)

    Suvorova, Anna I.; Tyukova, Irina S.; Trufanova, Elena I.

    2000-05-01

    The effects of low-molecular-weight additives, temperature and mechanical action on the structure and properties of starch are discussed. Special attention is given to mixtures of starch with synthetic polymers, e.g., co-polymers of ethylene with vinyl acetate, vinyl alcohol, acrylic acid, cellulose derivatives and other natural polymers. These mixtures can be used in the development of novel environmentally safe materials (films, coatings, packaging materials) and various articles for short-term use. The bibliography includes 105 references.

  12. Production of multiple extracellular enzyme activities by novel submerged culture of Aspergillus kawachii for ethanol production from raw cassava flour.

    Science.gov (United States)

    Sugimoto, Toshikazu; Makita, Tomohiro; Watanabe, Koutaro; Shoji, Hiroshi

    2012-04-01

    Cassava is a starch-containing root crop that is widely used as a raw material in a variety of industrial applications, most recently in the production of fuel ethanol. In the present study, ethanol production from raw (uncooked) cassava flour by simultaneous saccharification and fermentation (SSF) using a preparation consisting of multiple enzyme activities from Aspergillus kawachii FS005 was investigated. The multi-activity preparation was obtained from a novel submerged fermentation broth of A. kawachii FS005 grown on unmilled crude barley as a carbon source. The preparation was found to consist of glucoamylase, acid-stable α-amylase, acid carboxypeptidase, acid protease, cellulase and xylanase activities, and exhibited glucose and free amino nitrogen (FAN) production rates of 37.7 and 118.7 mg/l/h, respectively, during A. kawachii FS005-mediated saccharification of uncooked raw cassava flour. Ethanol production from 18.2% (w/v) dry uncooked solids of raw cassava flour by SSF with the multi-activity enzyme preparation yielded 9.0% (v/v) of ethanol and 92.3% fermentation efficiency. A feasibility study for ethanol production by SSF with a two-step mash using raw cassava flour and the multi-activity enzyme preparation manufactured on-site was verified on a pilot plant scale. The enzyme preparation obtained from the A. kawachii FS005 culture broth exhibited glucose and FAN production rates of 41.1 and 135.5 mg/l/h, respectively. SSF performed in a mash volume of about 1,612 l containing 20.6% (w/v) dry raw cassava solids and 106 l of on-site manufactured A. kawachii FS005 culture broth yielded 10.3% (v/v) ethanol and a fermentation efficiency of 92.7%.

  13. Characterization of an 18,166 EST dataset for cassava (Manihot esculenta Crantz) enriched for drought-responsive genes.

    Science.gov (United States)

    Lokko, Y; Anderson, J V; Rudd, S; Raji, A; Horvath, D; Mikel, M A; Kim, R; Liu, L; Hernandez, A; Dixon, A G O; Ingelbrecht, I L

    2007-09-01

    Cassava (Manihot esculenta Crantz) is a staple food for over 600 million people in the tropics and subtropics and is increasingly used as an industrial crop for starch production. Cassava has a high growth rate under optimal conditions but also performs well in drought-prone areas and on marginal soils. To increase the tools for understanding and manipulating drought tolerance in cassava, we generated expressed sequence tags (ESTs) from normalized cDNA libraries prepared from dehydration-stressed and control well-watered tissues. Analysis of a total of 18,166 ESTs resulted in the identification of 8,577 unique gene clusters (5,383 singletons and 3,194 clusters). Functional categories could be assigned to 63% of the unigenes, while another approximately 11% were homologous to hypothetical genes with unclear functions. The remaining approximately 26% were not significantly homologous to sequences in public databases suggesting that some may be novel and putatively specific to cassava. The dehydration-stressed library uncovered numerous ESTs with recognized roles in drought-responses, including those that encode late-embryogenesis-abundant proteins thought to confer osmoprotective functions during water stress, transcription factors, heat-shock proteins as well as proteins involved in signal transduction and oxidative stress. The unigene clusters were screened for short tandem repeats for further development as microsatellite markers. A total of 592 clusters contained 646 repeats, representing 3.3% of the ESTs queried. The ESTs presented here are the first dehydration stress transcriptome of cassava and can be utilized for the development of microarrays and gene-derived molecular markers to further dissect the molecular basis of drought tolerance in cassava.

  14. Cassava; African perspective on space agriculture

    Science.gov (United States)

    Katayama, Naomi; Njemanze, Philip; Nweke, Felix; Space Agriculture Task Force, J.; Katayama, Naomi; Yamashita, Masamichi

    Looking on African perspective in space agriculture may contribute to increase diversity, and enforce robustness for advanced life support capability. Cassava, Manihot esculentaand, is one of major crop in Africa, and could be a candidate of space food materials. Since resource is limited for space agriculture in many aspects, crop yield should be high in efficiency, and robust as well. The efficiency is measured by farming space and time. Harvest yield of cassava is about 41 MJ/ m2 (70 ton/ha) after 11 months of farming. Among rice, wheat, potato, and sweet potato, cassava is ranked to the first place (40 m2 ) in terms of farming area required to supply energy of 5 MJ/day, which is recommended for one person. Production of cassava could be made under poor condition, such as acidic soil, shortage of fertilizer, draught. Laterite, similar to Martian regolith. Propagation made by stem cutting is an advantage of cassava in space agriculture avoiding entomophilous or anemophilous process to pollinate. Feature of crop storage capability is additional factor that determines the efficiency in the whole process of agriculture. Cassava root tuber can be left in soil until its consumption. Cassava might be an African contribution to space agriculture.

  15. 木薯渣发酵饲料的工艺筛选%Screening of technology in cassava slag fermentation feed

    Institute of Scientific and Technical Information of China (English)

    艾必燕; 刘长忠; 陈建康; 杨扬; 米本中; 黄倩妮; 樵星芳

    2012-01-01

    Using cassava slag as the main raw material, with aspergillus, trichoderma viride and rhizopus R2 for fermentation strains, the test is to optimize cassava slag fermentation technology producing tropina feed. The appropriate conditions of cassava slag fermentation are that adding amount of liquid spawn is 3%, adding amount of nitrogen source is 10%, fermentation temperature is 37 ℃, fermentation time is 4 days. Cassava slag is a mixture, its highest level of non-nitrogen compounds is 78.7%, main component is soluble starch compounds (such as monosaccharide and starch), but its crude protein content is very low, amino acid composition is extremely uneven, it has poor effect to feed cassava slag directly, so most of the cassava slag cannot be used, which not only causes the waste of resources, but also seriously pollutes environment. Processing cassava slag into feed materials can make full use of the waste in starch industry, it is favorable to the environment protection, and it also can significantly reduce the cost of feed, improve the utilization value and economic benefits of cassava slag.%以木薯生产中产生的废渣为主要原料,以黑曲霉、绿色木霉和根霉R2为发酵菌种,优化木薯渣发酵生产菌体蛋白饲料的工艺.初步确定了木薯渣发酵的适宜条件,即液体菌种添加量为3%,氮源添加量为20%,发酵温度37℃,发酵时间为4d,经试验验证,此发酵条件下发酵饲料中粗蛋白含量较高,可达到蛋白饲料对蛋白质含量的要求.通过处理木薯渣变为动物的饲料原料,不仅可充分利用淀粉工业的废弃物,有利于环境保护,而且可显著降低饲养成本,从而提高了木薯渣的利用价值和经济效益.

  16. Cassava Processing: Safety and Protein Fortification

    OpenAIRE

    2012-01-01

    Cassava (Manihot esculenta Crantz) is an important and cheap source of carbohydrate in tropical regions, particularly in Sub-Sahara Africa. Cassava as a human food is a good source of energy as it has a comparable high energy density of about 610 kJ/100 g fresh root. The crop has growth advantages and production can take place in soil where other crops such as maize, sorghum and sweet potatoes cannot grow. In the region, cassava is used mainly by the farmers themselves as a subsistence crop b...

  17. Green natural rubber-g-modified starch for controlling urea release.

    Science.gov (United States)

    Riyajan, Sa-Ad; Sasithornsonti, Yodsathorn; Phinyocheep, Pranee

    2012-06-05

    The hydrophilicity of natural rubber (NR) was improved by grafting with modified cassava starch (ST) (NR-g-ST) by using potassium persulfate (K2S2O8) as a catalyst. The modified ST was added to NR latex in the presence of Terric16A16 as a non-ionic surfactant at 60 °C for 3 h and cast film on a glass plate to obtain NR-g-ST. The chemical structure of NR-g-ST was confirmed by FTIR. The swelling ratio of NR-g-ST was investigated in water and results showed that the swelling ratio of the modified NR decreased as function of ST. In addition, the tensile strength of the modified NR in the presence of modified ST at 50 phr was the highest value. Also, the thermal stability modified NR-g-ST was higher than of NR/ST blend confirmed by TGA. Finally, the NR-g-ST was used a polymer membrane for controlling urea fertilizer and it easily degraded in soil. This product with good controlled-release and water-retention could be especially useful in agricultural and horticultural applications.

  18. Utilização de filmes plásticos e comestíveis na conservação pós-colheita de melão amarelo Utilization of PVC film and edible films to extend the postharvest conservation of yellow melons

    Directory of Open Access Journals (Sweden)

    Patrício F Batista

    2007-12-01

    Full Text Available Este trabalho teve como objetivo prolongar a vida pós-colheita de melões do tipo amarelo cv. AF-682, por meio da atmosfera modificada obtida com filme plástico de PVC e filmes comestíveis à base de cera de carnaúba (50% e fécula de mandioca (1, 2 e 3%. Para o revestimento dos frutos com embalagem plástica utilizou-se filme de PVC com 10 mm de espessura, aderente e esticável, colocado em camada única, na superfície de cada fruto. Após serem revestidos pelos filmes os frutos foram armazenados em temperatura ambiente de 29± 2ºC e 64±1% UR por 20 dias, sendo em intervalos de cinco dias submetidos às avaliações: massa individual, firmeza da polpa, teor de sólidos solúveis totais, acidez titulável e pH. Utilizou-se delineamento inteiramente casualizado com seis repetições em esquema fatorial 6x4, sendo 6 tratamentos de conservação e 4 períodos de armazenamento. Nenhum dos tratamentos avaliados é recomendável para aumentar a conservação pós-colheita de melão amarelo. Os frutos revestidos com fécula de mandioca a 3% e filme de PVC apresentaram processo iniciais característicos de fermentação e podridão a partir de 15 dias de armazenamento em temperatura ambiente.This work aimed to extend the postharvest life of yellow melons cv. AF-682 through modified atmosphere techniques obtained with PVC film and edible films such as carnauba wax (50% and cassava starch (1, 2 and 3%. Fruits were wrapped with one layer of adherent and stretchable PVC film with 10 mm width. After covering, fruits were stored at 29± 2ºC and 64±1% UR for 20 days. At a 5-day interval, fruits were evaluated for individual weight, pulp firmness, total soluble solids content, titratable acidity and pH. The trial was carried out in a complete randomized design, with six replications in a factorial scheme 6x4, with six treatments and four storage periods. The use of PVC film and edible films are not recommended to extend postharvest conservation of

  19. Comparasion of iles-iles and cassava tubers as a Saccharomyces cerevisiae substrate fermentation for bioethanol production

    Directory of Open Access Journals (Sweden)

    KUSMIYATI

    2010-01-01

    Full Text Available Kusmiyati (2010 Comparasion of iles-iles and cassava tubers as a Saccharomyces cerevisiae substrate fermentation for bioethanol production. Nusantara Bioscience 2: 7-13. The production of bioethanol increase rapidly because it is renewable energy that can be used to solve energy crisis caused by the depleting of fossil oil. The large scale production bioethanol in industry generally use feedstock such as sugarcane, corn, and cassava that are also required as food resouces. Therefore, many studies on the bioethanol process concerned with the use raw materials that were not competing with food supply. One of the alternative feedstock able to utilize for bioethanol production is the starchy material that available locally namely iles-iles (Amorphophallus mueller Blum. The contain of carbohydrate in the iles-iles tubers is around 71.12 % which is slightly lower as compared to cassava tuber (83,47%. The effect of various starting material, starch concentration, pH, fermentation time were studied. The conversion of starchy material to ethanol have three steps, liquefaction and saccharification were conducted using α-amylase and amyloglucosidase then fermentation by yeast S.cerevisiaie. The highest bioethanol was obtained at following variables starch:water ratio=1:4 ;liquefaction with 0.40 mL α-amylase (4h; saccharification with 0.40 mL amyloglucosidase (40h; fermentation with 10 mL S.cerevisiae (72h producing bioethanol 69,81 g/L from cassava while 53,49 g/L from iles-iles tuber. At the optimum condition, total sugar produced was 33,431 g/L from cassava while 16,175 g/L from iles-iles tuber. The effect of pH revealed that the best ethanol produced was obtained at pH 5.5 during fermentation occurred for both cassava and iles-iles tubers. From the results studied shows that iles-iles tuber is promising feedstock because it is producing bioethanol almost similarly compared to cassava.

  20. Physicochemical properties of yam bean starch%凉薯淀粉的理化性质研究

    Institute of Scientific and Technical Information of China (English)

    张喻; 章丽琳; 曾嵘; 曾希珂

    2016-01-01

    The granular morphology and size,solubility,swelling power,pasting property and other physicochemical properties of starches from yam bean were analyzed by comparing the similarities and differences with corn,cassava and potato starches. The results indicated that most of yam bean starch granules were irregular polygon,and granule sizes were smaller than the other three kinds of starches, which varied from 3~11 μm with the average was 8 μm. The solubility and swelling power were higher than those of cassava and corn starches,but lower than those of potato starches,which increased with the rise of temperature. Gelatinization temperature of yam bean starch was 80 ℃,which was higher than the other three kinds of starches. Peak viscosities were less than those of potato and cassava starches, but higher than those of corn starches. Thermal stability of yam bean starches was the strongest. Aging abilities were stronger than those of potato and corn starches,but smaller than those of cassava starches. The transparency of yam bean starches was very low and it was easy to coagulation sink. The apparent viscosity of yam bean starches was small,showing the phenomenon of shear thinning. The freeze–thaw stability of yam bean starches was very bad. The gel hardness,chewiness,cohesion and adhesion of yam bean starches were far lower than those of potato and cassava starches,higher than those of corn starches and gel elasticity of yam bean were the lowest.%以玉米淀粉、木薯淀粉和马铃薯淀粉为对照,分析了凉薯淀粉的颗粒形貌及大小、溶解度、膨胀度和糊化特性等理化性质。结果表明:凉薯淀粉颗粒形状多为不规则多边形,少数为圆形,粒径范围为3~11μm,平均粒径为8μm,小于其他三种淀粉;溶解度和膨胀度比木薯淀粉和玉米淀粉高,比马铃薯淀粉低,且随温度升高,溶解度和膨胀度显著增大;糊化温度为80℃,高于其他三种淀粉,峰值黏度小于

  1. Processing surface sizing starch using oxidation, enzymatic hydrolysis and ultrasonic treatment methods--Preparation and application.

    Science.gov (United States)

    Brenner, Tobias; Kiessler, Birgit; Radosta, Sylvia; Arndt, Tiemo

    2016-03-15

    The surface application of starch is a well-established method for increasing paper strength. In surface sizing, a solution of degraded starch is applied to the paper. Two procedures have proved valuable for starch degradation in the paper mill: enzymatic and thermo-oxidative degradation. The objective of this study was to determine achievable efficiencies of cavitation in preparing degraded starch for surface application on paper. It was found that ultrasonic-assisted starch degradation can provide a starch solution that is suitable for surface sizing. The molecular composition of starch solutions prepared by ultrasonic treatment differed from that of starch solutions degraded by enzymes or by thermo-oxidation. Compared to commercial degradation processes, this resulted in intensified film formation and in greater penetration during surface sizing and ultimately in a higher starch content of the paper. Paper sized with ultrasonically treated starch solutions show the same strength properties compared to commercially sized paper.

  2. Energy Value of Cassava Products in Broiler Chicken Diets with or without Enzyme Supplementation.

    Science.gov (United States)

    Bhuiyan, M M; Iji, P A

    2015-09-01

    This study investigated the metabolizable energy (ME) intake, net energy of production (NEp), heat production (HP), efficiencies of ME use for energy, lipid and protein retention as well as the performance of broiler chickens fed diets based on cassava chips or pellets with or without supplementation with an enzyme product containing xylanase, amylase, protease and phytase. The two products, cassava chips and pellets, were analysed for nutrient composition prior to feed formulation. The cassava chips and pellets contained 2.2% and 2.1% crude protein; 1.2% and 1.5% crude fat; and 75.1% and 67.8% starch, respectively. Lysine and methionine were 0.077%, 0.075%, and 0.017%, 0.020% protein material, respectively, while calculated ME was 12.6 and 11.7 MJ/kg, respectively. Feed intake to day 21 was lower (pproduction was highest (pproduction, and the nutritive value of such diets can be improved through supplementation of enzyme products containing carbohydrases, protease, and phytase.

  3. A new alkalophilic isolate of Bacillus as a producer of cyclodextrin glycosyltransferase using cassava flour

    Directory of Open Access Journals (Sweden)

    Sheila Lorena de Araújo Coelho

    2016-03-01

    Full Text Available Abstract Cyclodextrin glycosyltransferase (CGTase catalyzes the conversion of starch into non-reducing cyclic sugars, cyclodextrins, which have several industrial applications. This study aimed to establish optimal culture conditions for β-CGTase production by Bacillus sp. SM-02, isolated from soil of cassava industries waste water lake. The optimization was performed by Central Composite Design (CCD 2, using cassava flour and corn steep liquor as substrates. The maximum production of 1087.9 U mL−1 was obtained with 25.0 g L−1 of cassava flour and 3.5 g L−1 of corn steep after 72 h by submerged fermentation. The enzyme showed optimum activity at pH 5.0 and temperature 55 °C, and maintained thermal stability at 55 °C for 3 h. The enzymatic activity was stimulated in the presence of Mg+2, Ca+2, EDTA, K+, Ba+2 and Na+ and inhibited in the presence of Hg+2, Cu+2, Fe+2 and Zn+2. The results showed that Bacillus sp. SM-02 have good potential for β-CGTase production.

  4. Hyperphosphorylation of cereal starch

    DEFF Research Database (Denmark)

    Carciofi, Massimiliano; Shaik, Shahnoor Sultana; Jensen, Susanne Langgård

    2011-01-01

    Plant starch is naturally phosphorylated at a fraction of the C6 and the C3 hydroxyl groups during its biosynthesis in plastids. Starch phosphate esters are important in starch metabolism and they also generate specific industrial functionality. Cereal grains starch contains little starch bound......-type phenotype. Transgenic cereal grains synthesized starch with higher starch bound phosphate content (7.5 (±0.67) nmol/mg) compared to control lines (0.8 (±0.05) nmol/mg) with starch granules showing altered morphology and lower melting enthalpy. Our data indicate specific action of GWD during starch...... biosynthesis and demonstrates the possibility for in planta production of highly phosphorylated cereal starch....

  5. 正交试验法研究淀粉-壳聚糖可食性包装膜的力学性能%Study on Mechanical Properties of Starch-chitosan Edible Packaging Film

    Institute of Scientific and Technical Information of China (English)

    方健; 卢虹; 方艳平; 符克丽

    2009-01-01

    采用溶液共混后流延的方法制备淀粉-壳聚糖可食性包装膜,运用正交试验法研究了壳聚糖质量分数、乙酸体积分数、淀粉质量分数、共混时间、甘油比例等因素对包装膜力学性能的影响.根据正交试验结果,壳聚糖质量分数、乙酸体积分数、甘油比例对包装膜的抗张强度和伸长率影响最为显著.当壳聚糖质量分数2%,乙酸体积分数6%,淀粉质量分数2%,共混时间10 min,甘油质量比例35%时,共混膜的力学性能相对最优.%Starch-chitosan edible packaging films were prepared by solution and tape casting method. Mechanical properties of EPF were studied with orthogonal test method and the influence of chitosan concentration, acetic acid concentration, starch concentration, blending time, and glycerine proportion on the mechanical properties of the film was analyzed. The results showed that chistosan concentration, acetic acid concentration, and glycerine proportion were the important factors for the tensile strength and elongation of EPF. The optimized condition was chitosan concentration 2 %, acetic acid concentration 6 %, starch concentration 2%, blending time 10 min, and glycerine proportion 35%.

  6. 阿魏酸对马铃薯淀粉基复合膜性能的影响%Effect of ferulic acid on properties of potato starch-based composite films

    Institute of Scientific and Technical Information of China (English)

    贾超; 王利强; 卢立新; 谢甲有

    2013-01-01

    以马铃薯淀粉、普鲁兰多糖、明胶为成膜物质,甘油为增塑剂,阿魏酸为交联剂,采用流延法制备马铃薯淀粉基复合膜,研究了阿魏酸含量对复合膜物理机械性能的影响.结果表明:阿魏酸能够改善复合膜的机械性能和阻湿性能,减小复合膜的水溶性,但会显著降低复合膜的透光率,且使复合膜的颜色发黄.其中,添加1%阿魏酸的复合膜性能较好,其抗拉强度为14.33MPa,断裂伸长率为9.36%,水蒸气透过率为4.52g· mm·m-2·d-1·kPa-1,水溶性为28.46%,透光率为77.37%.%Potato starch-based composite films were obtained by casting using potato starch, pullulan, gelatin as film-forming material,glycerol as plasticizer,ferulic acid as cross-linking agent.The effect of the contents of ferulic acid on physical and mechanical properties of composite films were investigated.The results showed that ferulic acid improved the mechanical properties and moisture barrier properties of the composite films, reduced the water-solubility of the composite films. However, it reduced the light transmission rate of the composite films significantly,and made the color of the composite films yellow.The properties of composite films containing 1% ferulic acid were better, the tensile strength was 14.33MPa, elongation at break was 9.36%, water vapor permeability was 4.52g·mm·m-2·d-1·kPa-1, water- solubility was 28.46%, light transmission rate was 77.37%.

  7. Irradiated gelatin-potato starch blends: evaluation of physicochemical properties

    Energy Technology Data Exchange (ETDEWEB)

    Inamura, Patricia Y.; Regis, Wellington; Mastro, Nelida L., E-mail: nlmastro@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Macromolecular polysaccharides of large chains as starch can interlace with gelatin modifying their mechanical resistance. In this work, biodegradable bovine gelatin-potato starch blends films were developed using glycerol as plasticizer. Three formulations of gelatin/starch proportions (w/w) were used (1:0; 3:1; 1:1) and casting was the chosen method. The dried samples were then submitted to ionizing radiation coming from an electron beam (EB) accelerator with doses of 20 and 40 kGy, at room temperature, in the presence of air. Mechanical properties such as puncture strength and elongation at break were measured. Color measurements, water absorption, moisture, and film solubility were assessed. The results showed that starch addition to films based on gelatin as well as irradiation affected physical and structural properties of the films. Although the increase of starch content in the mixture led to decrease of the puncture force even in samples irradiated with the higher dose, there was a decrease of water absorption of films with the increase of the dose, and also by the higher starch content. Samples irradiated at 20 kGy presented higher moisture and film solubility. The methodology developed in this paper can be applied to other composite systems to establish the best protein:starch ratio, and the contribution of the radiation crosslinking in each specific case. (author)

  8. RNAi-mediated resistance to Cassava brown streak Uganda virus in transgenic cassava.

    Science.gov (United States)

    Yadav, Jitender S; Ogwok, Emmanuel; Wagaba, Henry; Patil, Basavaprabhu L; Bagewadi, Basavaraj; Alicai, Titus; Gaitan-Solis, Eliana; Taylor, Nigel J; Fauquet, Claude M

    2011-09-01

    Cassava brown streak disease (CBSD), caused by Cassava brown streak Uganda virus (CBSUV) and Cassava brown streak virus (CBSV), is of new epidemic importance to cassava (Manihot esculenta Crantz) production in East Africa, and an emerging threat to the crop in Central and West Africa. This study demonstrates that at least one of these two ipomoviruses, CBSUV, can be efficiently controlled using RNA interference (RNAi) technology in cassava. An RNAi construct targeting the near full-length coat protein (FL-CP) of CBSUV was expressed constitutively as a hairpin construct in cassava. Transgenic cassava lines expressing small interfering RNAs (siRNAs) against this sequence showed 100% resistance to CBSUV across replicated graft inoculation experiments. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis showed the presence of CBSUV in leaves and some tuberous roots from challenged controls, but not in the same tissues from transgenic plants. This is the first demonstration of RNAi-mediated resistance to the ipomovirus CBSUV in cassava.

  9. Understanding the role of plasticisers in spray-dried starch

    NARCIS (Netherlands)

    Niazi, Muhammad Bilal Khan; Zijlstra, Mark; Broekhuis, Antonius A.

    2013-01-01

    Amorphous thermoplastic starch (TPS) films were produced by compression moulding of solution spray-dried TPS powder and by direct solution casting. Oxidised potato starch was used as a feedstock for production of plasticised formulations containing glycerol or urea, or their combinations with maltod

  10. Characteristics of raw starch degrading alpha-amylase from Bacillus aquimaris MKSC 6.2 associated with soft coral Sinularia sp.

    NARCIS (Netherlands)

    Puspasari, Fernita; Nurachman, Zeily; Noer, Achmad Saefuddin; Radjasa, Ocky Karna; van der Maarel, Marc J. E. C.; Natalia, Dessy

    2011-01-01

    Partially purified alpha-amylase from Bacillus aquimaris MKSC 6.2, a bacterium isolated from a soft coral Sinularia sp., Merak Kecil Island, West Java, Indonesia, showed an ability to degrade raw corn, rice, sago, cassava, and potato starches with adsorption percentage in the range of 65-93%. Corn h

  11. 机械活化醋酸酯淀粉的制备及其生物降解塑料膜性能%Preparation of mechanical activated starch acetate and performance research of the biodegradable plastic films

    Institute of Scientific and Technical Information of China (English)

    陈渊; 黄祖强; 谢祖芳; 朱万仁; 伍念荣

    2011-01-01

    In order to improve properties of starch-based biodegradable plastic films, the mechanical activated starch acetate (MASA) was synthesized from mechanical activated maize starch (MAS) with activation time for 1.0 h. At the same time, the biodegradable plastic films were produced by thermal gelatinization of starch suspensions blending MASA with degree of substitution and polyvinyl alcohol (PVA). By Fourier transform infrared spectrogram (FTIR),differential scanning calorimetry (DSC) and scanning electron microscopy (SEM), the microstructure, particle shape,thermal stability were studied. The mechanical properties and biodegrade ability of the MASA/PVA were investigated by comparing with those of native starch acetate (SA). The results indicated that the microstmcture and particle shape changed greatly and thermal property of MASA increased compared with those of MAS and native starch. The properties of MASA/PVA were better than those of SA/PVA, and the tensile strength of the MASA/PVA with MASA (DS=0.1) was 3.56 MPa, the breaking elongation was 146.22% before soaking in water, and the absorption of water was 134.79% after 24 h. Hot water resistance properties was good, and the rate of biodegradation was 45.90% in the soil after 20 days. The mechanical activation pretreatment effectively improved the properties of biodegradable plastic films.%为了有效提高淀粉基生物降解塑料的性能,本试验对机械活化1.0 h的玉米淀粉(MAS)进行酯化改性,制备了机械活化醋酸酯淀粉(MASA)及机械活化醋酸酯淀粉/聚乙烯醇的牛物降解塑料膜(MASA/PVA),用傅立叶红外光谱仪(FTIR)、差示扫描量热仪(DSC)、扫描电镜(SEM)分别对MASA的结构、热稳定性、形貌等进行测试和表征,并与原醋酸酯淀粉/聚乙烯醇生物降解塑料膜(SA/PVA)对比研究了塑料膜的力学性能和生物降解性能.结果表明,机械活化淀粉经酯化改性后,结构和形貌都有很大的改变,热性能提

  12. Starch nanocrystals and starch nanoparticles from waxy maize as nanoreinforcement: A comparative study.

    Science.gov (United States)

    Bel Haaj, Sihem; Thielemans, Wim; Magnin, Albert; Boufi, Sami

    2016-06-05

    The morphological, structural and thermal behavior of starch nanocrystals (SNCs) extracted from waxy maize starch through an acid hydrolysis were compared with those of starch nanoparticles (SNPs) obtained through an ultrasound treatment starting from the same waxy maize starch. The SNPs were found to be completely amorphous, slightly smaller and had no surface charge, whereas the SNCs had the expected platelet-like morphology with a negative surface charge introduced as a result of the use of sulphuric acid in the acid hydrolysis step. SNCs also showed better thermal stability than SNPs in the presence of water. As a result of their platelet-like morphology, the SNCs performed better in reinforcing a polymer film. On the other hand, SNPs reduced the transparency of the nanocomposite films to a lesser extent than the SNCs due to their smaller size.

  13. Production of methane by co-digestion of cassava pulp with various concentrations of pig manure

    Energy Technology Data Exchange (ETDEWEB)

    Panichnumsin, Pornpan [The Joint Graduate School of Energy and Environment, King Mongkut' s University of Technology Thonburi, Thungkru, Bangkok 10140 (Thailand); Excellent Center of Waste Utilization and Management, National Center for Genetic Engineering and Biotechnology, Bangkhuntien, Bangkok 10150 (Thailand); Nopharatana, Annop [Pilot Plant Development and Training Institute, King Mongkut' s University of Technology Thonburi, Bangkhuntien, Bangkok 10150 (Thailand); Ahring, Birgitte [AAU, Copenhagen Institute of Technology, Lautrupvang 15, 2750 Ballerup (Denmark); Chaiprasert, Pawinee [School of Bioresources and Technology, King Mongkut' s University of Technology Thonburi, Bangkhuntien, Bangkok 10150 (Thailand)

    2010-08-15

    Cassava pulp is a major by-product produced in a cassava starch factory, containing 50-60% of starch (dry basis). Therefore, in this study we are considering its potential as a raw material substrate for the production of methane. To ensure sufficient amounts of nutrients for the anaerobic digestion process, the potential of co-digestion of cassava pulp (CP) with pig manure (PM) was further examined. The effect of the co-substrate mixture ratio was carried out in a semi-continuously fed stirred tank reactor (CSTR) operated under mesophilic condition (37 C) and at a constant OLR of 3.5 kg VS m{sup -3} d{sup -1} and a HRT of 15 days. The results showed that co-digestion resulted in higher methane production and reduction of volatile solids (VS) but lower buffering capacity. Compared to the digestion of PM alone, the specific methane yield increased 41% higher when co-digested with CP in concentrations up to 60% of the incoming VS. This was probably due to an increase in available easily degradable carbohydrates as the CP ratio in feedstock increased. The highest methane yield and VS removal of 306 mL g{sup -1} VS{sub added} and 61%, respectively, were achieved with good process stability (VFA:Alkalinity ratio < 0.1) when CP accounted for 60% of the feedstock VS. A further increase of CP of the feedstock led to a decrease in methane yield and solid reductions. This appeared to be caused by an extremely high C:N ratio of the feedstock resulting in a deficiency of ammonium nitrogen for microbial growth and buffering capacity. (author)

  14. Characterization of chestnut (Castanea sativa, mill starch for industrial utilization

    Directory of Open Access Journals (Sweden)

    Ivo Mottin Demiate

    2001-03-01

    Full Text Available Studies were conducted to characterize the chestnut and its starch. Chemical composition of the chestnuts showed high level of starch. Moisture level in the raw nuts was around 50g/100g in wet basis and starch content, around 80g/100g in dry basis; other nut flour components were protein (5.58 g/100g, lipid (5.39 g/100g, crude fiber (2.34 g/100g and ash (2.14 g/100g. Starch fraction was chemically characterized in order to identify the granule quality as compared with those of cassava and corn. This fraction showed more lipids and proteins than the other starches. Chestnut starch granules showed peculiar shape, smaller than the control starches and low amount of damaged units. Chemical composition concerning amylose : amylopectin ratio was intermediate to that presented by cassava and corn starch granules. Water absorption at different temperatures as well as solubility were also intermediate but closer to that presented by cassava granules. The same behavior was observed in the interaction with dimethyl-sulfoxide. Native starch granules and those submitted to enzymatic treatment with commercial alpha-amylase and also with enzymes from germinated wheat were observed by scanning electronic microscopy. Water suspensions of chestnut starch granules were heated to form pastes that were studied comparatively to those obtained with cassava and corn starches. Viscographic pattern of chestnut starch pastes showed a characteristic profile with high initial viscosity but peak absence, high resistance to mechanical stirring under hot conditions and high final viscosity. There was no way to compare it with the paste viscographic profiles obtained with the control starches. Chestnut starch pastes were stable down to pH 4 but unstable at pH 3. The water losses observed in the chestnut starch pastes after freeze-thaw cycles showed more similarity to the pattern observed in corn starch pastes as well as clarity and strength of the gel. In general the results

  15. Imidazole-based deep eutectic solvents for starch dissolution and plasticization.

    Science.gov (United States)

    Zdanowicz, Magdalena; Spychaj, Tadeusz; Mąka, Honorata

    2016-04-20

    Potato starch and high-amylose starch were treated with imidazole-based deep eutectic solvents (DESs) as dissolution and plasticization media. Beside imidazole (IM) for two-component DESs preparation choline chloride (CC), glycerol (G) or carboxylic acids (citric or malic) were used. An influence of water content in starch (as well as an extra water in the starch/DES system) on polymer dissolution and plasticization processes was investigated. Dissolution and gelatinization of starch in DESs were followed via DSC and laser scanning microscopy. A rheometric characteristics revealed an influence of starch/DES system storage time on the plasticization process. The tendency to recrystallization of compression-molded-starch films was evaluated using XRD technique. High dissolution and plasticization effectiveness of CC/IM and G/IM and a low tendency to film retrogradation of thermoplasticized starch were noted.

  16. Effect of starch particles on foam stability and dilational viscoelasticity of aqueous-foam

    Institute of Scientific and Technical Information of China (English)

    Yongqiang Zhang; Zhidong Chang; Wenli Luo; Shaonan Gu; Wenjun Li; Jianbo An

    2015-01-01

    Surface dilational rheological behavior and foam stability of starch/surfactant mixed solutions were studied at differ-ent starch concentrations and constant surfactant concentration. The results show that dilational viscoelasticity modulus, dilational elasticity modulus and dilational viscosity modulus increase with the concentration of starch particles. Foam stability increases with dilational viscoelasticity. Foam strength also increases with starch concentra-tion. Starch particles play a positive effect on foam stability and dilational viscoelasticity and the effect becomes more significant as drainage proceeds. Film pictures indicate that the film with 20%(by mass) starch particles is thicker than that without starch. Starch particles gather in Plateau border and resist drainage, making the foam more stable. © 2014 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. Al rights reserved.

  17. Enzymatic modification of starch

    DEFF Research Database (Denmark)

    Jensen, Susanne Langgård

    In the food industry approaches for using bioengineering are investigated as alternatives to conventional chemical and physical starch modification techniques in development of starches with specific properties. Enzyme-assisted post-harvest modification is an interesting approach to this, since...... branching connecting larger chain segments. In case of high BE activity this transfer happened prior to hydration and phase separation. The starch substrates thereby became locked in their granular structure and blocked furher access of BE. Transferase-based modification of starch has today almost...... exclusively been conducted on gelatinized starch. This study provides a new concept for transferase-based modification of starches in granular state....

  18. Preparation and Properties of Starch Based Biodegradable Water Retaining Film for Cultivating Lentinus edodes%淀粉基香菇菌棒用生物降解保水膜的制备和性质

    Institute of Scientific and Technical Information of China (English)

    樊燕鸽; 张娟梅; 赵俊宏; 李文锋; 侯益民

    2016-01-01

    The biodegradable water retaining film prepared by polyvinyl alcohol(PVA),oxidized starch and stearic acid was used in mushroom-stick instead of plastic bags. The film were investigated by X-ray diffraction. The mechanical properties,biodegradable properties and condition adaptability were studied. Test results showed that it has well mechanical properties,biodegradability,breathability and can preserve moisture while PVA:oxidized starch was 6∶4,stearic acid was 4%,water-retaining agent was 6%. The film of none-cutting was used in mushroom-stick can save resources and labor. It’s green and safe.%以聚乙烯醇、氧化淀粉、硬脂酸为主要原料制备可生物降解保水膜,替代塑料袋应用于香菇菌棒的保水。采用X-射线衍射仪对该生物降解保水膜进行结构表征,并对其使用性能和环境适应性进行研究。结果表明:当硬脂酸4%,PVA与氧化淀粉比例为6∶4(质量比),保水助剂6%时,该膜具有良好的力学使用性能、保水透气性和生物降解性,应用于香菇种植过程中不需人工剪口,不仅节约资源和劳动力,而且安全环保。

  19. Gas Transmission and Water Vapor Transmission Properties of High-Amylose Corn Starch/Chitosan Edible Film%高直链玉米淀粉-壳聚糖复合膜透气透水性能研究

    Institute of Scientific and Technical Information of China (English)

    陈琼; 邱礼平; 马细兰

    2011-01-01

    In this experiment, edible films from high-amylose com starch (HACS) and chitosan (CS) were developed by casting film-solution on leveled trays. The effects of ratio of starch to chitosan, glycerol dosage and methylcellulose (MC) dosage on CO2 and O2 transmission, water vapor transmission (WVT) of edible films were investigated. The result showed that the edible composite fihns had the lowest CO2 and O2 transmission and lower WVT when the ratio of chitosan and content of glycerol reach 2:1. The value of CO2 and O2 transmission increase to the highest and then decrease, and WVT increased while the ratio of chitosan and content of glycerol continued decrease. The increase of content of glycerol improved the CO2, O2 transmission and WVT of edible films first, and then decreased gradually. The addition of 2% methylcellulose decreased the gas permeability properties of the edible film to the lowest When the content of methylcellulose was between 4% and 6%, WVT of the edible film reached the lowest.%本文以高直链玉米淀粉(HACS)和壳聚糖(CS)为基本材料,甘油为增塑剂,甲基纤维素(MC)为增强剂制备可食性复合膜,研究了高直链玉米淀粉与壳聚糖的配比、甘油的添加量以及甲基纤维素的添加量对复合膜的透气透水性能的影响.结果表明,HACS:CS为2:1时,膜的CO2透过量和O2透过量最低,水蒸气透过量(WVT)也处于较低水平.随着HACS:CS的降低,膜的CO2透过量和O2透过量增加到最大值再降低,而WVT值呈增大趋势.甘油量的增加使复合膜的CO2透过量和O2透过量先增加后降低,而WVT变化趋势与透气量一致.MC的添加量为2%时,HACS/CS复合膜的透气量最低,而在MC添加量4%~6%时,膜的WVT最低.

  20. Phenotypic Approaches to Drought in Cassava: Review

    Directory of Open Access Journals (Sweden)

    Emmanuel eOkogbenin

    2013-05-01

    Full Text Available Cassava is an important crop in Africa, Asia, Latin America and the Caribbean. Cassava can be produced adequately in drought conditions making it the ideal food security crop in marginal environments. Although cassava can tolerate drought stress, it can be genetically improved to enhance productivity in such environments. Drought adaptation studies in over three decades in cassava have identified relevant mechanisms which have been explored in conventional breeding. Drought is a quantitative trait and its multigenic nature makes it very challenging to effectively manipulate and combine genes in breeding for rapid genetic gain and selection process. Cassava has a long growth cycle of 12 - 18 months which invariably contributes to a long breeding scheme for the crop. Modern breeding using advances in genomics and improved genotyping, is facilitating the dissection and genetic analysis of complex traits including drought tolerance, thus helping to better elucidate and understand the genetic basis of such traits. A beneficial goal of new innovative breeding strategies is to shorten the breeding cycle using minimized, efficient or fast phenotyping protocols. While high throughput genotyping have been achieved, this is rarely the case for phenotyping for drought adaptation. Some of the storage root phenotyping in cassava are often done very late in the evaluation cycle making selection process very slow. This paper highlights some modified traits suitable for early-growth phase phenotyping that may be used to reduce drought phenotyping cycle in cassava. Such modified traits can significantly complement the high throughput genotyping procedures to fast track breeding of improved drought tolerant varieties. The need for metabolite profiling, improved phenomics to take advantage of next generation sequencing technologies and high throughput phenotyping are basic steps for future direction to improve genetic gain and maximize speed for drought tolerance

  1. Phenotypic approaches to drought in cassava: review.

    Science.gov (United States)

    Okogbenin, Emmanuel; Setter, Tim L; Ferguson, Morag; Mutegi, Rose; Ceballos, Hernan; Olasanmi, Bunmi; Fregene, Martin

    2013-01-01

    Cassava is an important crop in Africa, Asia, Latin America, and the Caribbean. Cassava can be produced adequately in drought conditions making it the ideal food security crop in marginal environments. Although cassava can tolerate drought stress, it can be genetically improved to enhance productivity in such environments. Drought adaptation studies in over three decades in cassava have identified relevant mechanisms which have been explored in conventional breeding. Drought is a quantitative trait and its multigenic nature makes it very challenging to effectively manipulate and combine genes in breeding for rapid genetic gain and selection process. Cassava has a long growth cycle of 12-18 months which invariably contributes to a long breeding scheme for the crop. Modern breeding using advances in genomics and improved genotyping, is facilitating the dissection and genetic analysis of complex traits including drought tolerance, thus helping to better elucidate and understand the genetic basis of such traits. A beneficial goal of new innovative breeding strategies is to shorten the breeding cycle using minimized, efficient or fast phenotyping protocols. While high throughput genotyping have been achieved, this is rarely the case for phenotyping for drought adaptation. Some of the storage root phenotyping in cassava are often done very late in the evaluation cycle making selection process very slow. This paper highlights some modified traits suitable for early-growth phase phenotyping that may be used to reduce drought phenotyping cycle in cassava. Such modified traits can significantly complement the high throughput genotyping procedures to fast track breeding of improved drought tolerant varieties. The need for metabolite profiling, improved phenomics to take advantage of next generation sequencing technologies and high throughput phenotyping are basic steps for future direction to improve genetic gain and maximize speed for drought tolerance breeding.

  2. Starch and cellulose nanocrystals together into thermoplastic starch bionanocomposites.

    Science.gov (United States)

    González, Kizkitza; Retegi, Aloña; González, Alba; Eceiza, Arantxa; Gabilondo, Nagore

    2015-03-01

    In the present work, thermoplastic maize starch based bionanocomposites were prepared as transparent films, plasticized with 35% of glycerol and reinforced with both waxy starch (WSNC) and cellulose nanocrystals (CNC), previously extracted by acidic hydrolysis. The influence of the nanofiller content was evaluated at 1 wt.%, 2.5 wt.% and 5 wt.% of WSNC. The effect of adding the two different nanoparticles at 1 wt.% was also investigated. As determined by tensile measurements, mechanical properties were improved at any composition of WSNC. Water vapour permeance values maintained constant, whereas barrier properties to oxygen reduced in a 70%, indicating the effectiveness of hydrogen bonding at the interphase. The use of CNC or CNC and WSNC upgraded mechanical results, but no significant differences in barrier properties were obtained. A homogeneous distribution of the nanofillers was demonstrated by atomic force microscopy, and a shift of the two relaxation peaks to higher temperatures was detected by dynamic mechanical analysis.

  3. 淀粉成膜性和疏水性对表面施胶包装纸的影响%Effects of Film Forming and Hydrophobic Properties of Starches on Surface Sized Packaging Paper

    Institute of Scientific and Technical Information of China (English)

    Anna Jonhed; Caisa Andersson; Lars Jarnstrom; 张莉

    2009-01-01

    The effect on mechanical and barrier properties upon addition of glycerol to temperature-responsiv ehydrophobically modified(HM) potato starch was studied on free films. The addition of glycerol lowered the glass transition temperature, the storage modulus and the water vapor permeability(WVP) for the HM starch films. The HM starch phase separates upon cooling below an upper critical temperature into a solid and a liquid phase. Adding glycerol to the warm starch solution had an inhibiting effect on the particulate precipitation. Substrates surface sized with respect to barrier properties; WVP, contact angle and Cobb values. Hydroxypropylated starch was used as a reference. Cobb values and WVP results on surface-sized substrates indicated that the film formation properties of the starches were 6f great importance for the final surface properties. Good film formation properties were essential for the gas barrier and water resistance while they were less important for high contact angles. The WVP decreased as the glycerol content of the sizes increased, but no sufficient water vapor barriers could be obtained. The HM starches investigated in this work provided good oxygen barrier and the contact angles indicated a hydrophobic character of the surface. The role of the precipitate was investigated, and surface sizing with the precipitate gave low WVP and high contact angles despite its poor film-forming properties under the experimental conditions. Cobb60 values were slightly improved for HM starch with increasing glycerol content over glycerol-free sizing.%本文研究了添加甘油对疏水改性木薯淀粉膜力学性能及阻隔性能的影响,甘油的添加降低了疏水改性淀粉膜的玻璃转化温度、储能模量及水蒸气透过量.当温度低于临界温度上限时,疏水改性淀粉将会出现固态及液态两种形式.热的淀粉溶液中加入适量的甘油可以抑制淀粉微粒的沉淀.与羟丙基淀粉相比,疏水改性淀粉中添

  4. Analysis of the Character of Film Decomposition of Starch Acetate (SA) Coated Urea by Infrared Spectrum%红外光谱分析醋酸酯淀粉包膜尿素膜降解特征

    Institute of Scientific and Technical Information of China (English)

    李东坡; 武志杰; 梁成华; 陈利军; 张玉兰; 聂彦霞

    2012-01-01

    The degradability characteristics of film with 4 kinds of starch acetate coated and inhibitors amended urea were analyzed by FTIR, which was purposed to supply theoretical basis for applying starch acetate coated urea fertilizers in farming. The result showed that the chemical component, molecule structure and material form of the membrane were not changed because of adding different inhibitors to urea. The main peaks of the film degradation process were brought by the H-O, -OH, CO2, C-O , -CH2, -CH3, C-O, C-O-H and C-O-C vibrancy in asymmetry and symmetry. In brown soil, the trend of absorbing value of the most high peak was 0>15>30>60>90>120>150>310 d. The infrared spectra of 4 kinds of fertilizers were not different remarkably, and the film