bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on Rye Starch Properties and Modification. Part I: Composition and Properties of Rye Starch Granules
Authors: Schierbaum Friedrich , Radosta Sylvia , Richter Manfred , Kettlitz Bernd , Gernat Christine 
Published: November 2006

AbstractRye is considered as a potential raw material for starch industry. Starting from a survey of technical procedures of isolating starches from rye‐flour and ‐grits investigations will be reported, which were performed on pilot plant‐ and laboratory‐isolated rye starches. The present paper deals with its granule appearance and composition.A distribution of granule size between small granules (⩽ 10 μ − 15%) and large granules (⩾ 11 … ⩽ 40 μ − 85%) is typical for the totality of the starches. Differing distributions depend on the conditions of isolation: the entity of starch containing samples resulted from the laboratory procedures under investigation. Large‐granule starch preparations were isolated in the pilot plant: the centrifuge‐overflow contains the small‐granule fraction which is high in impurities. Granule crystallinity amounts to 16%. The crystalline component ‐ like in wheat and triticale starches ‐ consists predominatly of A‐polymorph ‐ with up to 9% of the B‐type. The isotherms of water exchange are of the cereal type.The contents of minor constituents largely relate to the small granule fraction which assembles the majority of crude protein, pentosans and lipids, which are difficult to removeLarge granule samples may be produced in high purity (⩽ 0,2% crude protein)
. Lipid components in all fractions influence the results of linear chain‐iodine interactions and they must be removed to proceed from apparent to absolute polysac‐charide indices. The absolute amylose contents amount to ∼ 25% for large granule samples and to 20–21% for small granule samples. The average chain‐length of iodine binding helical regions was determined with 220–240 AGU.
On Crystallinity in Cereal and Tuber Starches
Authors: Muhrbeck Per 
Published: November 2006

AbstractThe size and shape of the crystalline regions of wheat and potato starch were analyzed by X‐ray line broadening. It was found that wheat A‐ and B‐granules contained almost identical roughly spherical crystallites, about 100Å in size. Potato starch crystallites showed about the same dimensions in the different directions, but were somewhat smaller than wheat starch. The crystallite size agreed well with literature values of the radial length of the amylopectin cluster.
Measurements of the Refractive Index Increment on Hydroxyethyl Starch as a Basis for Absolute Molecular Weight Determinations
Authors: Kulicke Werner‐Michael , Kaiser Uwe , Schwengers Dieter , Lemmes Rolf 
Published: November 2006

AbstractSolutions of hydroxyethyl starch are used as a blood plasma substitute. If their physiological efficiency is to be optimized, they need to be accurately characterized in terms of their molecular weight and its distribution. The absolute determination of molecular weight and molecular weight distribution by means of light scattering require a knowledge of the refractive index increment. Although numerous investigations of the refractive index increment of hydroxyethyl starch have already been published, the results vary significantly due to the use of different samples and the choice of different measuring parameters. There was therefore an urgent need to examine the extent to which the refractive index increment depends on molecular parameters, the experimental method used and the type of processing. Here it was found that different sample preparations result in different contents of solid matter, so that an exact determination of the quantity is required. Hydroxyethyl starches in the molecular weight range of about Mw = 200.000 g/mol and varying degrees of substitution between DS 0.38 and 0.50 which are regarded as optimal for clinical use give a refractive index increment of dn/dc633nm = 0.146 = 0.005 cm3/g (solvent: H2O/0.02% NaN3; T = 25°C).
Thin‐Boiling and Nongelling Adhesive Prepared from Maize and Wheat Starches
Authors: Chung Koo Min , Seib Paul A. 
Published: November 2006

AbstractTo prepare thin‐boiling and nongelling adhesives, granular wheat and corn starches were thinned by treatment with aqueous hydrochloric acid or sodium hypochlorite and then hydroxypropylated with propylene oxide. Chlorine oxidation gave more rapid chain cleavage and whiter products with better freeze‐storage stability than acid‐treatment. Under the same depolymerization conditions, wheat starch was converted to a low viscosity granular starch more rapidly than corn starch. The best adhesive, judged by bonding strength, viscosity stability, and freeze‐thaw stability, resulted from wheat or corn starch oxidized with 0.82% Cl at pH 8.0 for 1 h followed by hydroxypropylation to molar substitution (M.S.) ∼ 0.07.
Seasonal Effects on the Physico‐chemical Properties of Starch from Four Cultivars of Cassava
Authors: Asaoka M. , Blanshard J. M. V. , Rickard J. E. 
Published: November 2006

AbstractFour varieties of cassava plants were cultivated at CIAT in Colombia 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‐ray 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.
Studies on Sago Starch. Part I: Characterization and Comparison of Sago Starches Obtained from Metroxylon sagu Processed at Different Times
Authors: Sim S. L. , Oates C. G. , Wong H. A. 
Published: November 2006

AbstractThis paper reports on a study undertaken to determine some of the factors responsible for the variability shown by sago starch, which at present severely limits the commercial value of this material. Two batches of sago starch extracted from Metroxylon sagu species were characterized physicochemically and structurally. One batch was white in colour while the other was reddish‐brown. The latter contained significantly more protein (0.06%) than the former (0.015%). Non‐proteinaceous material constituted 40% of the total nitrogen in the former. The ionic contents of the two batches of starch exhibited a similar ion profile except for the following striking differences. The white batch contained 20‐fold more phosphorus and 15‐fold more aluminium whilst the reddish‐brown batch contained double the quantity of iron and calcium. The solubility and swelling capacity of both batches were also different. Amylographic representation was used to reveal the strength of starch granules during pasting. Scanning electron microscopy disclosed different degrees of pitting between the two batches, the morphology of which were also shown to be disparate. Flow curves also displayed significant differences in the rheological behaviour.
Perspective Study of Vinyl Grafting onto Leucaena glauca Seed Gum and Guar Gum by Hydrogen Peroxide Initiation
Authors: Raval O. K. , Patel M. V. , Patel R. G. , Patel V. S. 
Published: November 2006

AbstractGraft copolymerization of various vinyl monomers onto Leucaena glauca seed gum has been performed using hydrogen peroxide as the initiator in aqueous slurry. Guar gum grafts also have been prepared to compare graftability of both the gums as they are structurally related to each other. To study the grafting behaviour of vinylic monomers towards the polygalactomannans the reaction conditions were kept constant for all the sets. The choosen monomers were acrylonitrile, methylmethacrylate, acrylamide, styrene, methacrylic acid and acrylic acid. The reaction products were characterized by grafting parameters like percent grafting, grafting frequency, grafting efficiency along with thermogravimetric and infra‐red spectroscopic analysis.
Studies on Rye Starch Properties and Modification. Part II: Swelling and Solubility Behaviour of Rye Starch Granules
Authors: Radosta Sylvia , Kettlitz Bernd , Schierbaum Friedrich , Gernat Christine 
Published: November 2006

AbstractRye starch shows the typical inhibited swelling behaviour of triticeae starches with an onset of swelling at rather low temperature (50–55°C). Swollen rye starch granules exist as individuals even after swelling at 100°C. The total dispersion of rye starch needs temperatures above 120°C with pressure cooking. On heating of the rye starch suspension preferentially amylose is leached. Defatting of rye starch exhibits no influence on swelling power but results in higher solubility and in increased amylose leaching. The drying procedures applied here resulted in stronger assoziation of the polymer molecules in the starch granule leading to higher swelling temperatures and a reduced solubility. Shiftings of the crystalline/ amorphous‐ratio of the starch granules as caused by different drying procedures, had no influence on the results of swelling power investigation but the highest swelling enthalpy as well as Brabender viscosity were exhibited by a sample dried at room temperature. It is proved to be possible to change the swelling behaviour of rye starch to “potato starch type” by slight chemical modification like succination.
Mechanism of Hydrolysis of the Treated Sago Starch Granules by Raw Starch Digesting Amylase from Penicillium brunneum
Authors: Haska Nadirman , Ohta Yoshiyuki 
Published: November 2006

AbstractWe have prepared raw starch digesting amylase from Penicillium brunneum, which is similar to other raw starch digesting enzymes, and is effective in hydrolyzing raw cereal starches, but not effective for raw sago starch and raw root starches. Treatment of sago starch granules before incubation with the enzyme by heating to below gelatinization temperature at low pH condition was effective in improving the hydrolysis. Observation by scanning electron microscope showed that structure of treated sago starch granules at 60°C pH 2.0 for 2h was not changed. Observation under polarized light showed the birefringence clearly was preserved. However, viscosity of treated sago starch granules decreased. After incubation with the enzyme, untreated starch granules corroded and several holes were seen on the surface of granule. Enzyme action on the treated starch granules resulted in much higher intensity of degradation and the holes deepened into the interior of granules. Analysis of the product of this process showed that mainly glucose was produced from the hydrolysis of treated or untreated sago starch granules by crude enzyme. But on gelatinized sago starch other types of sugars were formed during enzyme reaction.
Digestibility of Sweet Potato Raw Starches by Glucoamylase
Authors: Noda Takahiro , Takahata Yasuhiro , Nagata Tadahiro , Monma Mitsuru 
Published: November 2006

AbstractThree crude glucoamylase preparations from Rhizopus sp., Chalara paradoxa and Aspergillus sp. K‐27 were used to determine the digestibility of raw starches from eight sweet potato varieties. Granule sizes and amylose contents were also measured. The average granule sizes ranged between 10.5 and 14.2 μm. The amylose contents varied between 18.2 and 21.8%. The hydrolysis rates for the raw starches by any of the three glucoamylases were similar. However, starch of the variety Hi‐starch had a slightly lower hydrolysis rate than other starches when Rhizopus sp, enzyme was used.
Flow Behaviour of Mung Bean Starch Pastes
Authors: Oates C. G. , Lee W. P. 
Published: November 2006

AbstractThe rheological properties of mung bean starch pastes were characterised using a co‐axial rotational viscometer. The flow curves of pastes were typical of a viscoplastic shear thinning behaviour, no yield value was evident and the pastes showed unusual resistance to high shear forces. The rheological properties of these pastes were thought to result from the combined influence of intact swollen granules and an extensive extragranular network of exuded amylose.
Fractionation of Starch Amylopectin and Amylose by High Performance Gel Filtration Chromatography
Authors: Kennedy J. F. , Rivera Z. S. , Lloyd L. L. , Warner F. P. 
Published: November 2006

AbstractA gel filtration chromatographic method has been developed which is capable of fractionating amylose and amylopectin in starch. Three GFC columns (2 × 4000 A and 1 × 300A PL Separation Sciences, Polymer Laboratories Ltd,) are used in series using sodium chloride solution as eluent. Minimal sample preparation is involved which includes a preliminary wetting of powder starch with ethanol followed by dissolution with sodium hydroxide. Since the solvent system is aqueous, cooked starch samples are analysed by direct dissolution with sodium hydroxide. The method shows promise as a rapid technique in elucidating starch structure.
Studies on Starch Granules Digestion by α‐Amylase
Authors: Sreenath Hassan K. 
Published: November 2006

AbstractRaw corn starch was partially digested with commercial α‐amylase for a short period of 7–8 h at 25°C to obtain granular pitting. The patterns of granular digestion was observed by light and scanning electron microscopy (SEM). The main soluble products of starch digestion were glucose, maltose and higher oligosaccharides. In vitro digestion of starch was discontinued on the basis of nature of granular pitting and relative release of glucose in the reaction mixture. The pitted starch was obtained with high yields and found to be warm water soluble.
The Dehydration of Fructose Towards 5‐Hydroxymethylfurfural Using Activated Carbon as Adsorbent
Authors: Vinke P. , van Bekkum H. 
Published: November 2006

Abstract5‐Hydroxymethylfurfural (HMF) can be selectively adsorbed onto activated carbon with loadings up to 30% (w/w), depending on the type of carbon used. Adsorption isotherms of HMF on several types of carbon and in different solvents are presented. Activated carbon is used in in the dehydration of fructose towards HMF in order to suppress the formation of side‐products (e. g. levulinic acid). A dehydration set‐up in which the formation and adsorption of HMF take place at different temperatures is presented. The HMF is recovered by extraction of the loaded activated carbon with organic solvent.
Physicochemical Studies on Starches Isolated from Plantain Cultivars, Plantain Hybrids and Cooking Bananas
Authors: Eggleston Gillian , Swennen Rony , Akoni Stephen 
Published: November 2006

AbstractStarches from mature, unripe fruit pulp of plantain cultivars (Musa supp., AAB group) representing the wide variability in Africa, tetraploid and diploid plantain hybrids and starchy cooking bananas (Musa spp., ABB group) were isolated and characterised. In general, studies revealed very compact irregularly shaped and sized granules, with low amylose content (9.11–17.16%), highly resistant to bacterial α‐amylase attack; Brabender amylograms showed very restricted swelling type patterns with great stability and negligible retrogradation. Results indicate that differences in physico‐chemical properties exist amongst the three Musa fruit group starches. Plantains represent a chemical/molecular homogeneous group, but heterogeneous for granule structure. Ploidy level affected hybrid properties. ABB cooking bananas starches exhibited highly pronounced restricted swelling and high gelatinisation and pasting temperatures, indicating a more ordered, very strongly bonded granule structure; chemical and physical properties varied considerably within the ABB genotype.
Modifications of Urethane‐Foam Formulations Using Zea mays Carbohydrates
Authors: Cunningham R. L. , Carr M. E. , Bagley E. B. , Nelsen T. C. 
Published: November 2006

AbstractFour carbohydrates derived from Zea mays (corn), ordinary cornstarch, two high‐amylose starches (one instant starch), and canary dextrin, were substituted partially (8–30%) for polyether polyol in rigid polyurethane foams. Because of different carbohydrate water contents the level of substitution was chosen for each carbohydrate to maintain uniform water contents in the foams. In addition, a lower level of canary dextrin was added to one formulation to evaluate the effect of water addition. With the exception of the dextrin‐filled foams, which were similar in density to the controls, the carbohydrate‐filled foams were more dense (0.0280–0.0296 versus 0.0272 g/cm3). Substitution of 8% of the polyether polyol with Amalean I (high‐amylose starch) increased the density by 9%. With 15–16% substitution of the polyether with instant starch or dextrin, the compressive strength values of the foams were 10–16% lower than for the control foams. Exchanges of 8–16% polyether with any of the four carbohydrates resulted in 3–4% and 4–5% increases in volumes after 14 days of accelerated aging under thermal (70°C, ambient RH) and humid (38°C. 97% RH) conditions, respectively. The lowest priced carbohydrate, cornstarch, substituted at the 10% level for the polyether provided foams exhibiting 4% less compressive strength and similar insulating value than the control foams without carbohydrate. Since the polyether polyol is ten times more expensive than cornstarch, further study of utilizing corn‐derived carbohydrates as polyols in foam formulation is merited.
Composition of Polydextrose® Before and After Intestinal Degradation in Rats
Authors: Radosta Sylvia , Boczek Peter , Grossklaus Rolf 
Published: November 2006

AbstractThe alternative carbohydrate Polydextrose® was separated by gel permeation chromatography (GPC) with an aminomodified silicagel and by high performance liquid chromatography (HPLC) on a silvercharged cation exchanger. It has been proved that Polydextrose® contains about 32% oligomers with a degree of polymerization of up to four. Because of the great variability of binding types between the glucose monomers, a satisfactory chromatographic separation is not yet possible. The degradation of Polydextrose® in the small intestine of rats is an accidental event; there are no especially resistent molecules in this process. Within 3 h after oral administration, the spectrogram of high‐and low‐molecular fractions of Polydextrose® was not changed by digestion in the small intestine irrespective the visible decrease of glucose. Thus, this study gives new insights into the molecular composition of Polydextrose®.
Studies on Sweet Potatoes. Part I: Changes in the Carbohydrates During Processing
Authors: Susheelamma N. S. , Reddy G. Changala , Rukmani C. S. , Tharanathan R. N. 
Published: November 2006

AbstractThe qualitative and quantitative changes in the nature of different carbohydrate fractions of sweet potatoes (hard and soft cooking types), after dry (baking and toasting) and wet (steaming) processing have been studied. Maltose, glucose and fructose were the predominant sugars in the ethanol soluble fraction. The total sugar and amylose contents significantly decreased in the ethanol insoluble residues. This was supported by the decrease in blue value and the absorption maxima of the iodine complex.
Hydrothermal Modification of Starches: The Difference between Annealing and Heat/Moisture ‐Treatment
Authors: Stute Rolf 
Published: November 2006

AbstractAnnealing and heat/moisture‐treatment both cause a physical modification of starches without any gelatinization, or any other damage of the starch granules with respect to size, shape or birefringence only via a controlled application of heat/moisture. Since with respect to the application properties (gelatinization. viscosity etc.) almost idential modifications can be obtained with both treatments, there was no exact differentiation between the two treatments types.By application of both treatments as well as a combination of both to potato starch it could be demonstrated that both treatments cause completely different alterations of the internal granule structure. From the interpretation of the Brabender viscosity, the sorption isotherm, the DSC‐curves and the X‐ray diagrams it could be confirmed that a heat/moisture‐treatment always means a structure alteration from a B‐type in the direction of an A‐type structure, whereas within annealing processes the property alteration have to be explained by a modification of the binding forces between the crystallites and the amorphous matrix.
Flow Cytometric Determination of Light Scattering and Absorbance Properties of Starch Granules
Authors: Jones Robert J. , Srienc Friedrich , Roessler Jeffrey , Paul St. 
Published: November 2006

AbstractTreatment of samples of digested endosperm with SDS resulted in a homogenous suspension of single starch granules that was suitable for analysis by flow cytometry without altering their refractive properties. Flow cytometry can be used for more rapid and accurate enumeration of starch granules than can be achieved with a hemocytometer as with the latter the number of starch granules seems to be underestimated. Moreover, flow cytometric analysis based on forward angle light scatter (FALS) and absorbance properties revealed that there are at least three unique subclasses of starch granules that appear during kernel development. The first subclass contained mainly small granules (2–5 μm) whereas the second subclass generally consisted of large granules (> 5 μm). However, within a given size, there were two distinct subpopulations with significantly different absorbance properties. The physiological or physicochemical significants of these subclasses warrant further investigation.
USDA Research on Starch‐Based Biodegradable Plastics
Authors: Doane William M. 
Published: November 2006

AbstractResearch on starch‐based biodegradable plastics began in the 1970's and continues today at the National Center for Agricultural Utilization Research (NCAUR) in Peoria, IL. Technology has been developed for producing extrusion blown films and injection molded articles containing 50% and more of starch. Extrusion processing of compositions containing starch and other natural polymers to provide totally biodegradable plastics is being investigated. Starch grafted with thermoplastic side chains is under commercial development to provide injection molded items with a broad range of compositions and properties. The mechanism of biological degradation and the rate and extent of biodegradation of starch containing plastics in various environments is studied to enhance development and acceptance of biodegradable plastics.
Analysis of the Amylolytic Enzyme System of Clostridium thermosulfurogenes EM1: Purification and Synergistic Action of Pullulanases and Maltohexaose Forming α‐Amylase
Authors: Spreinat Andreas , Antranikian Garabed 
Published: November 2006

AbstractDuring growth of C. thermosulfurogenes EM1 on starch, seven forms of pullulanase and one form of α‐amylase were detected after gel electrophoretic separation of proteins. By determining the isoelectric points and N‐terminal sequences of various pullulanase species it was evident that no structural differences exist between these proteins. These pullulanases hydrolyzed α‐1,4‐ and α‐1,6‐linkages in various soluble sugar polymers causing their breakdown to maltose and maltotriose. Unlike these enzymes, the α‐amylase produced by C. thermosulfurogenes EM1 preferentially attacked non‐soluble starch. The main product of hydrolysis was maltohexaose. The combined action of pullulanases and α‐amylase on native starch showed synergistic effect. This synergistic effect was not observed if soluble starch was used as substrate.
Maltodextrin Hydrolysis with Glucoamylase Immobilized in Polyacrylamide Gel
Authors: Yankov D. , Peeva L. , Beschkov V. 
Published: November 2006

AbstractThe immobilization of glucoamylase by entrapping in a polyacrylamide gel has been studied. The optimum values of pH and temperature for the immobilized enzyme have been determinated. The influence of worked off cycles, substrate concentration and initial degree of hydrolysis on the final conversion of starch have been investigated.