bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Conformation of Amylose in Dilute Solution
Authors: Banks W. , Greenwood C. T. 
Published: November 2006

AbstractThe hydrodynamic behaviour of amylose in dilute solution has been examined in detail. Evidence for, and against, the existence in aqueous solution of a conformation which is predominantly helical in character is critically discussed. Proper interpretation of the solution behaviour of amylose shows that the molecule is a statistical, or random, coil having no helical content in neutral, aqueous solution. In such solutions, the presence of complexing agents causes a coil‐to‐helical in character is critically discussed. Proper interpretation of the solution behaviour of in the presence of salt represents a change from random coil to helix, and not as hitherto suggested, a helix‐to‐coil transition.
Absolute und relative Verkleisterungscharakteristik von Stärken. Teil I. Absolute Viskositätsmessung nach dem Searle‐Prinzip
Authors: Winkler S. , Luckow G. , Donie H. 
Published: November 2006

The Absolute and the Relative Gelatinization Characteristics of Starches. Part 1. Absolute Viscosity Measurings (Searle Principle).The rheometric conditions for executing absolute measurings of gelatinization characteristics of potato, maize and wheat starches without change of the preparation container are explained, and the results of coaxial cylinder measurings by “Rotovisko” at the absolute viscograms of the starch pastes are discussed.For absolute measurings of starch viscosities the preparation of the starch dispersions from the suspension of starch granules from the beginning of the swelling process to the formation of the homogeneous phase in turbulent current conditions is necessary; relative viscosities of the preparation phase show the swelling characteristics of the starches.By comparing different instruments of the same type their accuracy of measuring is traced at the absolute viscograms throughout the whole gelatinization range as a function of the rate of shear, and a comparison of starch viscosities by the gelatinization maxima of the absolute viscograms is proposed.
Reaction of Hexamethylphosphorus Triamide with Starch Studies on a new phosphorus starch derivative
Authors: Rosenthal Feiga R. T. , de Araújo Vania M. R. H. 
Published: November 2006

AbstractOn studying the reaction between hexamethylphosphorus triamide and starch, several reaction media were tried aiming to a medium in which derivatives with a low degree of substitution would be obtained. The greatest yield (phosphorus content up to 0.7%) was achieved by refluxing the mixture in organic solvents. The granules of the derivatives so obtained were quite modified. They swell in cold water, are insoluble in organic solvents, are strongly anionic and their gelatinization temperatures decrease with the increase in the degree of substitution. Their pastes, either when cold or hot, present similar viscosity values.
Über die Technologie der Verarbeitung von Maisgrits zu Stärke
Authors: Jahn F. 
Published: November 2006

On the Technology of Processing of Maize Grits to Starch.At the production of maize products of a low fat content, such as corn flakes or brewery grits, there results on principle a very fatty maize grit of a farinaceous structure in a quantity of 12 to 30 % which is hard to sell. From these waste grits there can be manufactured a quality starch, which complies with the quality designations with regard to protein, fat, ash, and viscosity.The process newly developed and applied for a patent was tested in an existing factory. By means of an intensive steeping the steeping time can be reduced to 1/4 to 1/3 of the normal maize steeping time. The steeping water is separated free of starch by means of a special decanter. The fat content of the steeped maize grit reduces thereby down to 1/8 of the original value. The steeped maize grit is ground and the resulting milk is treated further like in a normal starch factory, at which the separation of husks and germs is eliminated.The process enables maize mills to process also soft sorts of maize such as a German maize. In this case there results at the dry grinding a high yield of fine, fatty waste grits. Without further processing to starch the grinding of soft sorts of maize would, therefore, be uneconomical.
Oxidation of Starch by Hydrogen Peroxide in the Presence of UV Light‐Part II
Authors: Harmon Robert E. , Gupta S. K. , Johnson J. 
Published: November 2006

AbstractVarious reaction variables in the hydrogen peroxide oxidation of starch in the presence of UV light have been investigated. Higher carboxyl and carbonyl contents of oxystarches were obtained under acidic than under alkaline conditions. Extent of oxidation was found to increase with time. Increasing the concentration of hydrogen peroxide results in an increase in the carboxyl and carbonyl contents. Apparently, air has no effect on the degree of oxidation whereas, oxygen seems to accelerate it.
A Model for the Structure of Hydroxypropyl Starches
Authors: Leegwater D. C. 
Published: November 2006

AbstractThe exponential relation between degree of substitution (DS) and reducing power of pancreatin digests of hydroxypropyl starches, found in an earlier study, is explained by means of a statistical model. The model is based on the assumption that the hydroxypropyl groups are distributed at random over the starch molecules. It is shown that in that case the reducing power of the pancreatin digests is a function of (1 – DS)j. In this equation j is a constant; from the available data its numerical value was estimated to be 5.3. This result is interpreted as an indication that the pancreatic enzymes act only upon α(1→4) glucosidic chains containing five or more glucopyranose units.
Charakterisierung der Phosphorylase aus Kartoffeln durch Ultrazentrifuge und Gelpermeationschromatographie
Authors: Franken K.‐D. , Keilich G. , Husemann E. 
Published: November 2006

AbstractCharacterization of Potato Phosphorylase by Ultracentrifugation and Gel Permeation Chromatography. Potato phosphorylase was characterized by ultracentrifugation and gel permeation chromatography. The sedimentation constant was determined by sedimentation transport measurements at protein concentrations of 2 to 20 mg/ml. Using the equation of Scholtan the molecular weight of phosphorylase was found to be 200 000. The same value was obtained by gel permeation chromatography.In all experiments the phosphorylase behaved as a homogeneous component, whereas the measurements of sedimentation equilibrium showed a concentration dependence of the molecular weight indicating dissoziation of the phosphorylase protein into two components with a molecular weight of each 90 000. As the dissoziation of the phosphorylase into two subunits didn't bring about either an inactivation or a change of the specific activity the existence of an enzymatically active protein with a molecular weight of 90 000 is to be assumed.
The Effect of some Nitrate Salts on the Thermal Behaviour of Amylose
Authors: Desai D. H. , Patel C. K. , Patel K. C. , Patel R. D. 
Published: November 2006

AbstractIn the course of a series of thermo‐analytical investigations on amylose, attention has been focused on the acid salt catalysts. Studies on the sequence and nature of the chemical changes occuring in amylose during heating have been carried out by using differential thermal analysis (DTA) and thermogravimetric analysis (TGA).A strongly exothermic reaction, with some nitrate salts, was observed accompained by a rapid weight loss, not characteristic of any one of the substances in the mixtures. The exothermic decomposition could be explained as an oxidative attack of NO2on amylose, the former being produced by thermal decomposition of the nitrate salt. The kinetic parameters obtained from DTA are in accord with the results derived from TGA for the catalytic decomposition of amylose.
Absolute und relative Verkleisterungscharakteristik von Stärken. Teil II. Die relative Viskositätsmessung mit dem Schrägflügelkörper und der Einfluß amylolytischer Enzyme auf das Viskogramm
Authors: Winkler S. , Luckow G. , Donie H. 
Published: November 2006

AbstractThe Absolute and the Relative Gelatinization Characteristics of Starches.Part. 2. Relative Measuring of Viscosity by Special Wing Stirrer and the Influence of Amylolytic Enzymes on the Viscogram. The procedure of relative viscosity measurings of starches in the steeping and gelatinization phase by means of a special wing stirrer are described and the measuring results are discussed regarding the viscograms of potato, maize and wheat starch. Examples are given for the viscosimetric measuring of enzyme action. Especially the influence of α‐ and β‐amylase, of amyloglucosidase and papain on the relative viscograms of potato, maize and wheat starch is examined.
Versuche zur Verbesserung der Filtration von Stärkesirup
Authors: Hersiczky A. 
Published: November 2006

AbstractExperiments for Improvement of the Filtration of Starch Syrup. Possibilities for the improvement of starch syrup filtration according to these experimental results do not primarily depend on the type of plant which is used but on composition and the amount of suspended matter in syrups to be filtered. It was found that products of discontinually operating reactors are inhomogeneous. Even in products of 40 DE unsoluted starch could be traced. Laboratory tests have shown that a change of filtration rate of starch hydrolysates in the range below 46 DE is greater than in the range over 46 DE.A connection was found to exist between the degree of degradation and the electro‐kinetic properties. Moreover, it was found that the amount of filtration inhibiting matter cannot be reduced to a level below 5 vol.‐%. For the removal of these gel‐like components a gel separation unit for continual operation was constructed with a maximum capacity of 10 000 l/h. In practical application the apparatus removed 94% of the suspended matter extracted from the upper, middle and lower regions of the tank. Thus, the output of the filter station increased to 30 from 20 tons per day.
Study of the Crosslinking Reaction between Epichlorohydrin and Starch
Authors: Kuniak L. , Marchessault R. H. 
Published: November 2006

AbstractThe crosslinking of starch with epichlorohydrin under homogeneous and heterogeneous conditions has been studied with a particular view of measuring the extent of the side reaction wherein epichlorohydrin is substituted on the starch as a monoether derivative. The extent of this reaction, compared to the diether crosslink, was found to be strongly dependent on the reaction conditions (temperature, time, mole ratio of all reactants) and depending on these from 5 – 25 % of the applied epichlorohydrin is bound in the resulting product as a glycerol monoether substituent. The degree of swelling of the crosslinked starch was shown to be linearly dependent on the molar ratio of water to starch in the reaction mixture.It is shown that starch crosslinking proceeds with remarkable efficiency when epichlorohydrin is applied in the vapour phase. When crosslinking is performed under conditions which maintain the native granule structure the extent of monoether formation is about the same as for homogeneous crosslinking conditions.
Methoden zur Bestimmung des Wassergehaltes der Produkte des Naßvermahlungsprozesses unter Berücksichtigung ihres Einflusses auf die Ausbeuteberechnung
Authors: Meuser F. , Kempf W. 
Published: November 2006

AbstractMethods for Determination of Water Content in Products of Wet Milling Process with Regard to their Influence on the Field Calculation. The Karl‐Fischer‐Titration (KF) of water as described is applicable to all products of wet‐milling processes. The water content of starch hydrolysates including dextrose may be determined in the same way if pyridine is used instead of methanol as extraction solvent. The results obtained by KF‐titration proved to be in sufficient accord with the determination of water content by the oven‐drying‐method at 105°C. The oven‐drying‐method at 130°C seemed to be less suitable because losses of nonaqueous volatile compounds particularly of raw materials are not to be avoided and therefore may effect the results. By this too low dry‐substances of raw materials are obtained, which result into high recoveries when the outputs of wet‐milling‐processes are calculated. The differences between the starch recoveries as obtained in laboratory scale proved to be relatively small (max. 0,6%), however they may be of some importance within the total balance of wet‐mills.
Die rheologische Charakterisierung der Stärkegele
Authors: Djaković Lj. , Dokić P. 
Published: November 2006

AbstractRheological characterization of starch gels is a complicated problem as the measured values represent only an apparent viscosity. They depend on shearing stress respectively shearing rate and thus also on the type of viscosimeter used. Moreover starch gels are thixotropic, which brings about additional difficulties in measuring procedures and reproducibility of measured values.This paper has pointed out the possibilities of rheological characterization of starch gels by the parameters of rheological equations, as well as by the coefficients of thixotropy. Following the values of these parameters and coefficients it is possible to examine the changes in starch gels, caused by different factors (concentration changes, ageing, chemical modifications etc.).
Interaction of Potato Starch with Different Ligands
Authors: Osman‐Ismail F. , Solms J. 
Published: November 2006

AbstractThe formation of complexes of potato starch with 1‐hexanol, 1‐octanol, 1‐decanol, decanal, capric acid, stearic acid, oleic acid, linoleic acid, l‐menthone, l‐menthol and β‐pinene was investigated under equilibrium conditions. Binding parameters were calculated using an equation after Scatchard. The complexes were also examined with X‐ray diffraction measurements. Two types of binding take place, namely inclusion governed by helix formation and interactions with the surface of the helix or with other parts of the macromolecule. The binding constants and the stoichiometric compositions of the complexes were related to the molecular structure of the ligands.
Verarbeitungstechnische Eigenschaften von Inlandmais. 1. Trockenvermahlung
Authors: Bolling H. , Zwingelberg H. 
Published: November 2006

AbstractProcessing Poperties of Local Maize. 1. Dry Milling. The latest statistical informations published by the German Government indicate that about 600.000 t corn were harvested in 1971. That means 51,1 dz per unit of cultivated area with an increase of 20% per year in the corn production.The total amount of corn is used for animal feeding in Germany. Some products derived from maize from types US‐Yellow and Plata are used for cereal breakfast, starch manufacture and in brewing‐industry in other european countries. There is little, if any, available information about physical qualities of corn varieties grown in Germany. Thus, it has been felt of great importance to fill this gap.This work was carried out on 15 varities grown at different localities. The samples were milled into grits, semolina, meal, flour and germs on a Standard‐Corn‐Laboratory‐Mill. The milling products were analysed for their fat content. In general the yield of semolina with a low fat content may be affected by the variety as well as by locality. Some of the German varieties showed higher fractions of low fat content than US‐Yellow did.
Characterization of Colombian Maize Starches
Authors: De Buckle T. S. , Casabianca E. M. , Cárdenas O. S. 
Published: November 2006

AbstractStarch from 18 different Colombian maize varieties was extracted and characterized. Microscopic examination showed that most of the granules were larger than those reported for North American maize starches. Iodine binding capacities corresponded to those of normal maize starch. Limiting viscosity numbers demonstrated a significant increase beginning with Series 300 and gelatinization temperatures showed a tendency to decrease with increasing cultivation altitudes. Pasting curves of starches extracted from Opaque‐2 maize were considerably different from their respective parent hybrids.
Complexes of Starch and its Related Materials with Organic Compounds. Part VIII. Measurement of the Heats of Complex Formation of Cyclodextrins in Aqueous Solutions by Microcalorimeter
Authors: Takeo K. , Kuge T. 
Published: November 2006

AbstractCalorimetric studies have been made on the complex formation of cyclodextrins with triiodide ion or p‐nitrophenolate anion in aqueous solutions by using microcalorimeter. The heats of complex formation of α‐, β‐, and γ‐dextrin, respectively with both the guest compounds were obtained and marked differences in magnitude of the reaction heats were observed for the three dextrins. The association process of the dextrins with the guest compounds in aqueous solutions was briefly discussed with respect to the points of stoichiometry and thermodynamics.
Damaged Starch and Protein Contents in Relation to Water Absorption of Flours of Indian Wheats
Authors: Tara K. A. , Bains G. S. , Finney P. L. 
Published: November 2006

AbstractThe investigation has shown damaged starch to be a significant factor in the high water absorption by 63 straight‐run flours of a number of varieties of Indian wheats. A significantly high positive correlation (r = + 0.81 to + 0.87) was obtained between water absorption and damaged starch contents compared to a value of + 0.50 for water absorption and protein content. The prediction of water absorption from damaged starch and protein contents is discussed.
Studies on Tamarind Kernel Polysaccharides. Part II. Fractionation and Examination of Minor Component Polysaccharides
Authors: Srivastava H. C. , Krishnamurthy T. N. 
Published: November 2006

AbstractTamarind kernel powder has been fractionated by aqueous extraction and by complexing with copper to afford three fractions I—III. Fraction I contains sizable amounts of proteinous matter whereas fractions II and III are almost pure polysaccharides. Methylation of fraction III followed by hydrolysis produces 2,3,5‐tri‐O‐methyl‐L‐arabinose (1 mole); 2,3,4‐tri‐O‐methyl‐D‐xylose (1 mole); 2,3,4,6‐tetra‐O‐methyl‐D‐galactose (1 mole); 2,3,6‐tri‐O‐methyl‐D‐glucose (1 mole); 3,4‐di‐O‐methyl‐D‐xylose (1 mole); and 2,3‐di‐O‐methyl‐D‐glucose (3 moles). The structure of the polysaccharides is discussed in the light of the above results.
Studies on Tamarind Kernel Polysaccharide Part III. Structure of a Dextrin
Authors: Srivastava H. C. , Krishnamurthy T. N. 
Published: November 2006

AbstractTamarind kernel polysaccharide (TKP), isolated by fractionation of tamarind kernel powder, was heated at 153°C for 5 h in presence of 0.074% hydrochloric acid. The resulting product was fractionated to yield a homogeneous dextrin which on hydrolysis produced D‐xylose, D‐galactose and D‐glucose in the molar ratio of 2:1:10. Methylation of the dextrin followed by hydrolysis yielded 2,3,4‐tri‐O‐methyl‐D‐xylose (2 moles); 2,3,4,6‐tetra‐O‐methyl‐D‐glucose (1 mole); 2,3,4,6‐tetra‐O‐methyl‐D‐galactose (1 mole); 2,3,4‐tri‐O‐methyl‐D‐glucose (1 mole); 2,3,6‐tri‐O‐methyl‐D‐glucose (4 moles); 2,3‐di‐O‐methyl‐D‐glucose (4 moles); and 2‐O‐methyl‐D‐glucose (trace amounts). Upon oxidation of the dextrin with sodium metaperiodate, 1.4 moles of the oxidant was consumed with concomitant liberation of 0.38 mole of formic acid. Reduction of the oxopolysaccharide with sodium borohydride followed by acid hydrolysis of the polyol produced erythritol, glycerol and ethylene glycol in the molar ratio of 8:3:2.The above results suggest that the main reaction during dextrinization of TKP is that of hydrolysis. The side branches of the polymer are hydrolyzed to a greater extent than its backbone. Transglycosidation, which is the predominant reaction in starch dextrinization, takes place only to a small extent.
Beseitigung von Geruchsbelästigungen, verursacht durch Trockner in der Maisstärkeindustrie
Authors: Runge H. 
Published: November 2006

AbstractElimination of Odors caused by Dryers in the Corn Starch Industry. The rotary tube dryer is suited for drying pressed hulls. The vapors emitted by the dryer are odorless. Subsequent mixing with steepwater depends essentially on the absorption power of the material. This is best when the hulls, upon leaving the first dryer, still show sufficient moisture and when the inlet moisture at the second dryer — adjusted by dry material recycling — is kept below 35% H2O. The vapors produced when drying the hulls mixed with steepwater emit a distinct odor which can be eliminated by burning the vapors at temperatures above 800 °C, for instance in the furnace of a boiler. The decrease in efficiency during steam generation accounts for about 0.5 to 0.8%. To avoid that the temperature in the boiler falls below the dew point, it is recommended to heat the vapors emitted by the dryer on their way to the boiler furnace. A steam‐heated heat exchanger should be used if washing of the vapors was necessary as otherwise the heating system will be encrusted quickly.
Preparation of Amylose‐g‐Poly (Styrene)
Authors: Patel C. M. , Patel V. M. 
Published: November 2006

AbstractA study on the grafting of styrene on amylose has been made using H2O2 as an initiator and Cr3+, Fe2+, Co2+, Cu2+, Zn2+, and Ag+ ions as catalyst. It has been shown that with Fe2+ ions maximum grafting yield was obtained. The optimum conditions for the preparation of amylose‐g‐poly (styrene) have been set up.
Struktur und Eigenschaften gepfropfter Kartoffelsärke. II. Molekularer Aufbau der Propf‐co‐polymer‐Phase
Authors: Gruber E. , Alloush S. , Schurz J. 
Published: November 2006

Structure and Properties of Grafted Potatoe Starch. II. Molecular Structure of the Graft‐Co‐polymer PhaseThe copolymer molecules of potatoe starch, which had been grafted with poly‐(acrylic) acid and poly(methacrylic) acid resp. by the Scott‐xanthation‐process, consist of a backbone of amylopectin and of side chains of the synthetic polymer. There are always twice as many basic units of the side chain polymer in a molecule as there are anhydroglucose units. In solution the molecules are sphere‐like in shape and they show a relatively high coil density. For an explanation it is proposed, that the amylopectin backbone serves as a matrix for the propagation of the grafting polymerisation reaction. The side chains are lined up along the backbone and they remain attached to it, fixed by weak bonds.
Characterization of Amylose‐g‐Poly (Styrene)
Authors: Patel C. M. , Patel V. M. 
Published: November 2006

AbstractCharacterization of amylose‐g‐poly(styrene) has been carried out employing ultraviolet, differentional thermal analysis, infrared, nuclear magnetic resonance and solubility techniques. It has been concluded that amylose‐g‐poly(styrene) is a true graft copolymer.
The Fine Structure of Corn Starches of Various Amylose‐Percentage: Waxy, Normal and Amylomaize
Authors: Mercier Ch. 
Published: November 2006

AbstractThe fine structure of high‐amylose corn starches has been studied after dispersion of the starch and fractionation into their components amylose and amylopectin. The resulting amylopectin fraction reported in the literature possesses anomalous properties with regard to the waxy and normal amylopectin. However, the experimental results obtained by different authors for determining the structure lead to controversal explanations.Therefore, using an enzymic method, which permits the direct examination of the constitutive chains of the starch, the fine structure of the amylopectin of an amylomaize starch (64% amylose) has been investigated and compared with those of waxy and normal starches. The pullulanase – debranched chains are fractionated by gel permeation and their linearity are checked under the action of β‐amylase. The inner chains of the amylopectin fraction are studied after debranching of the β‐limit dextrins. The results show the identity between amylopectins from waxy and normal starches. The amylopectin fraction of amylomaize has its own structure with longer inner chains than those of waxy‐maize amylopectin.