bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Simplified Colorimetric Method for Determination of Amylose Content in Rice
Authors: Sowbhagya C. M. , Bhattacharya K. R. 
Published: November 2006

AbstractThe colorimetric iodine method of amylose estimation in rice has been simplified. The flour is dispersed in alkali by heating in water bath or by overnight soaking at room temperature. The extract is neutralized before colour development by direct addition of phenolphthalein and decolourizing with dilute acid.No simplified method of defatting (including extraction by methanol at room temperature) was found satisfactory. But apparent amylose content as determined in undefatted milled rice flour was close to 86% of the true value in 46 milled rice samples tested; hence determination without defatting and multiplication of the results with 1.16 was satisfactory for routine and approximate work. The apparent amylose value was, however, dependent on the degree of polish of the rice.Particle size of the flour within reasonable limits had no appreciable effect on the results. The extract was quite stable even when stored in the room temperature.
The Characterisation of Starch and Its Components Part 4. The Specific Estimation of Glucose Using Glucose Oxidase
Authors: Banks W. , Greenwood C. T. 
Published: November 2006

AbstractThe glucose oxidase/peroxidase technique for determining microgram quantities of glucose in aqueous solution has been critically examined. The function of each of the constituents in the solution has been studied, and the relation between time and temperature of incubation determined. Potential errors due to the temperature‐dependent pH‐behaviour of tris buffers, and the presence in the solution to be analyzed of high concentrations of buffer salts, glycerol, and reducing substances, are discussed. The relation between the absorbance, and the type and normality of acid used to stabilize the colour is examined.
Beiträge zur Geschichte der Stärke‐Mikroskopie. 2. Mitt.
Authors: Seidemann Johannes 
Published: November 2006

Contributions to the History of Starch Microscopy. Part 2.An answer to the question, how the different dates for the first detailed microscopie evidence of starch came about is followed by a closer look at the microscopie description and the graphic reproduction of wheat, bean and pea starch by A. van Leeuwenhoek.
Zusammenhang zwischen Konformation der Glucopyranoseeinheiten und Molekülkonfiguration der Amylose
Authors: Szejtli J. 
Published: November 2006

Relationship between the Conformation of the Glucopyranoside Units and the Molecular Configuration of Amylose.As a consequence of the tetrahedral valence angle as well as of the interactions between the H and OH groups attached to the C atoms the most probable form of D‐glucopyranose is the Cl conformation. The rotation around the oxygen‐bridge between the two glucopyranose units in maltose is hindered to such an extent that the existence only of that form seems to be probable, in which all similar substituents are placed on the same side of the molecule. The non‐bonded interaction between H–1 and H–4′ is diminished by a slight twisting of the plane of the two rings about the glucosidic bond in opposite directions. This arrangement renders possible the forming of O–2… O–3′ hydrogen bonds which contributes to the stabilization of the helical structure. Therefore under such conditions when this H bond is stable, the homologues of maltose – amylose too – achieve a helical molecular configuration.
Neuere Untersuchungen über die Lipide der Getreidestärken. I. Einleitung Methodik
Authors: Becker G. , Acker L. 
Published: November 2006

Recent Studies on Lipids of Cereal Starches. Part 1. Introduction and Methodology.A survey on the more recent works in the field of lipids of cereal starches is given. Subsequently, there is a report on the isolation of lipids of cereal starches and their analysis.
Some Observations on the Stability of Amylose and Amylopectin in Aqueous Solution
Authors: Greenwood C. T. , Hourston D. J. 
Published: November 2006

AbstractResults are presented for a series of light‐scattering experiments on the stability of the starch components, amylose and amylopectin, in 0.33 M KCl. Potato, regular maize amylose, and the amylose from two amylomaize starches have been studied. The findings are generally in agreement with previous studies in this area, but in the case of amylopectin, contrary to the findings of Čeh and Vene, no retrogradation has been observed.
Weizenstärkekörner. polarisationsoptisch und elektronenmikroskopisch
Authors: Czaja A. Th. 
Published: November 2006

AbstractIn earlier studies since 1961 [1] the author has observed that the A type starch granules of Wheat and other Hordeae show between crossed Nicols in most cases differentiated polarization crosses. In the center of these there is a little high double refracting disk with a small dark polarization cross. In the broader outer zone, which is not so bright, the armes of the small cross are persued much broader and indistinct.A. D. Evers (1971) has shown with the scanning electron microscope that the development of A type starch granules begins with an initial minute spherical granule, which becomes a „nucleus”︁, and which is progressively surrounded in the equatorial plane by a continually enlarging structure which resembles two lips with a furrow between them. When the lips have surrounded the „nucleus”︁ the thickness and diameter of the granule continue to increase in such a way that the furrow becomes shallower and is present in the mature biconvex structure only as a shallow score.
Studies on the Structure of Leguminosae Starches. 1. Solubility in Dimethyl Sulfoxide and by Enzymatic Action
Authors: Rosenthal Feiga R. T. , Nakamura Takeko 
Published: November 2006

AbstractIn order to elucidate the granular structure of the leguminous starches the speed of solubilization of several starches was determined by digestion with dimethyl sulfoxide and with α‐amylase. By microscopic investigations with normal and polarized light different forms of erosion were observed in the different starches, all of them less intense than those observed in cereal starches.It was concluded that the starch granules of mucunã seeds are the most homogeneous and have the least porous structure, followed by chick pea, jack, lablab and guanda beans. It is supposed that maturation, climate and soil influence the cristallinity of the granules, resulting in different digestibility.
Der fermentative Abbau der Kartoffelstärkekörner
Authors: Czaja A. Th. 
Published: November 2006

AbstractThe Fermentative Degradation of Potato Starch Granules. The difference between the fermentation of the starch granules as a whole in the living cells during germination of the potato tuber and the enzymatic destruction of the isolated starch granules by microorganisms (bacteria or fungi) is once more demonstrated. The last named process results by setting pores or little channels into the substance of the starch granules or following the weaker zones of the sheaths.
A Reassessment of the Chemical Structure of Barley and Wheat Starch Granules
Authors: Bathgate G. N. , Palmer G. H. 
Published: November 2006

AbstractBarley starch exists in two clearly defined populations of large (ca. 25 μ diameter) and small (ca. 5, μ diameter) granules, whilst in wheat there is a range of granule sizes with no similar bimodal distribution. The small granules of barley represent about 90% of the total starch granules by number, but account for only about 10% of the total starch in weight. Fractions containing only large or only small granules have been isolated from both barley and wheat. The small granules from barley have a higher amylose content than the large granules, a higher gelatinisation temperature, and are usually associated with more protein. In contrast, large and small granules from wheat differ only slightly in their respective amylose contents but, like barley differ in gelatinisation temperatures and amounts of associated protein. It is proposed that starch synthesis in the small starch granules of barley is under different genetic control from that in the large granules.
Critical Features of the Morgan Assay of Hydroxyethyl and Hydroxypropyl Substituents in Polysaccharides
Authors: De Belder A. N. , Persson Å. , Markström S. 
Published: November 2006

AbstractThe conditions for obtaining an accurate and reproducible assay of hydroxyethyl and hydroxypropyl substituents in the corresponding polysaccharide derivatives are described. Suitable compounds for standardising the procedure are described.
Einfluß der Klärmittel und ihrer Menge auf die polarimetrische Bestimmung von Kartoffelstärke nach Ewers
Authors: Dudáš F. 
Published: November 2006

AbstractInfluence of Clearing Agents and their Amount on Polarimetric Determination of Potato Starch According to Ewers. According to the results of chemical analysis and its statistical evaluation the Carrez clearing agent at an amount of 1 ml appears to be the most suitable for determination of starch in potatos. Use of sodium molybdate or ammonium molybdate led to lower values in average. Among these two sodium molybdate, as during examination of starch samples, appeared more suitable than ammonium molybdate. Phosphortungstic acid proved the least suitable. Normal as well as basic lead acetate after Horn did not show fully clear results upon revision. This is why they were not used.
5th Plenary Meeting of ISO/TC 93 in Paris
Authors: Kempf W. , Graefe G. 
Published: November 2006

AbstractThis article will report on the course and the result of the 5th Plenary Meeting of Technical Committee 93 of the International Organization for Standardization (ISO) which deals with standardization of analytical methods and test processes in the field of starch and its derivatives and by‐products. By invitation of the French Standardization Committee ”︁Association Française de Normalisation„ (AFNOR) it was held on Thursday 16, March and Friday 17, March, 1972, in Paris. There will be a report on the resolutions which were passed as recommendations in the course of the 2‐days Plenary Meeting as well as on resolutions passed – also as recommendations – by the two Sub‐Committees SC 1 ”︁General Problems„ and SC 3 ”︁Starch Hydrolysates„. The latter committees had been newly constituted by the Central Secretary's office during reorganization of the entire ISO/TC 93 in 1970 without questioning or consent of the technological experts. These committees gathered also in Paris fo the first meeting after their constitution on the 14th and 15th of March.
Influence of Food Emulsifiers on Pasting Temperature and Viscosity of Various Starches
Authors: Krog N. 
Published: November 2006

AbstractThe influence of monoglycerides (DGMS), stearoyl‐2‐lactylates (CSL, SSL), and diacetylated tartaric acid esters of monoglycerides (DATE) on amylograph curves of various starches has been investigated. DGMS gave the greatest increase in pasting temperature of wheat and tapioca starch, followed by SSL, CSL and DATE. The pasting temperature of corn and potato starch was less affected by these emulsifiers. Peak viscosity of wheat starch in distilled water was increased by all emulsifiers, and was decreased in tapioca and potato starch.Both pasting temperature and peak viscosity were strongly influenced by variations in pH, and were to some extent also dependent on ion concentration. In hard tap water the peak viscosity was slightly decreased by the anionic emulsifiers (SSL > CSL > DATE), due to the presence of Ca++ and Mg++ ions, while DGMS gave a higher peak viscosity than in distilled water. DATE seems to be more sensitive to variations in pH or ion concentration than the other emulsifiers.
Degree of Gelatinisation of Cooked Rice
Authors: Birch G. G. , Priestley R. J. 
Published: November 2006

AbstractA method for determining degree of gelatinisation of rice starch or rice flour, based on the amylose/iodine blue value after dispersion in alkali, has been developed. The method can be used to follow the course of cooking of rice under different conditions, and has been checked against a novel infrared technique for relating degree of gelatinisation to the phenomenon of hydrogen bonding.
Studies on the Biosynthesis of Starch Granules. Part 5. Properties of the Starch Components of Normal Barley, and Barley with Sturch of High Amylose‐Content, During Growth
Authors: Banks W. , Greenwood C. T. , Muir D. D. 
Published: November 2006

AbstractChanges in the molecular components of barley starch, from related genotypes of barley differing in amylose‐content, have been investigated over the period of reserve‐starch deposition in the plants. Striking similarities in the changes in amylose‐contents, and in the fine structure of component amylose and amylopectin fractions, were observed over this period, despite the large differences in the types of starch.
Investigations into and an Enzymic Assay Method of Transglucosidase Activity of Commercial Glucoamylase Preparations
Authors: Vámos L. , Rose P. 
Published: November 2006

AbstractAn enzymatic assay method was developed for the quantitative determination of transglucosidase activity in commercial glucoamylase preparations. The method is based on the determination of residual glucose after incubation of the glucoamylase preparation with this substrate under welldefined conditions (pH 4,2 and 30°C). Glucose determination was carried out by the glucose oxidase‐peroxidase method and transglucosidase activity expressed in international enzyme activity units. The over‐all time requirement of the analysis is 3 h with liquid and 26 h with powdered preparations. The variation coefficient was less than 3% in the former and 4% in the latter case. Optimum substrate concentration was found to be 8,3% w/v, higher glucose concentrations markedly inhibited the reaction at 30°C. Temperature optima were observed at 40 and 50°C, respectively, more elevated temperatures up to 60°C caused a strong decrease in activity.
Potentiometric Titration of Chloride in Corn Syrup Using the Chloride Ion Electrode
Authors: Jacin H. 
Published: November 2006

AbstractA potentiometric method for the determination of chloride ion in corn syrup was developed. Chloride is titrated with silver nitrate and the end point determined by a specific chloride‐ion electrode. The method is applicable to normal and deionized corn syrups. The recoveries of added chloride ranged from 97 to 101 percent. The relative standard deviation in a series of six determinations was 0.51%.
Determination of Silica in Corn Syrup
Authors: Jacin H. 
Published: November 2006

AbstractA method for the determination of silica in corn syrup is presented. A silico‐molybdate complex is formed. The interfering phospho‐molybdate is neutralized by the addition of oxalic acid. The silico‐molybdate complex is reduced by 1‐amino‐2‐naphthol‐4‐sulfonic acid to give the heteropoly blue which absorbs at 810 nm. Repeated analysis of a corn syrup gave a value of 17.8 microgram silica per gram of solids and a standard deviation of 0.06 for nine determinations. The recovery of added silica was in the range of 99–103%.
Studies on the Biosynthesis of Starch Granules. Part 7. Compound Granules in Potato Starch
Authors: Banks W. , Greenwood C. T. , Muir D. D. 
Published: November 2006

AbstractThe nature of compound starch granules in potato starch is examined. The relevance of this investigation to the possible formation of potato starch is discussed, and a mechanism for synthesis of compound granules proposed.
Développement des connaissances sur l'ultrastructure du grain d'amidon. I. L'amidon de blé
Authors: Gallant Par D. , Guilbot A. 
Published: November 2006

Developments in Starch Ultrastructure Knowledge. I. Wheat Starch Granules.The observations made by Sandstedt, in 1946, have been precised and explained with considerable improvement of technics for observations, especially with transmission and scanning electron microscopy. In the outline of the present reviewing concerning new developments in the wheat starch ultrastructure knowledge are studied: 1) The development of larger and smaller starch granules, extracted from the endosperm cells or examined in situ; 2) The lintnerization or enzymatic hydrolysis of lenticular shaped wheat starch granules; 3) The hydrolysis of smaller granules of which technological importance is recalled. A tridimensional diagram is given to complete the Buttrose's one, proposed in 1962.
Complexes of Starch and its Related Materials with Organic Compounds. Part. X. X‐Ray Diffraction of Amylose‐Fatty Acid Complexes
Authors: Takeo K. , Tokumura A. , Kuge T. 
Published: November 2006

AbstractX‐ray diffraction analyses of the complexes of amylose with a wide variety of fatty acids were carried out. The unit cell dimensions of the complexes were calculated for both the wet and dry states. Both the 61‐ and 71‐helical conformations of amylose were found in these complexes, and the conformation seems to depend on the linear chain length of the acid molecules. The orthorhombic unit cell was proposed for the 71‐helical structure of the wet complexes. The dibasic acid gave the crystal modification of the complexes exhibiting the diffraction pattern of hexagonal or orthorhombic nature. It was also found that complexations with n‐propionic acid give rise to three kinds of the patterns, depending on the amount of n‐propionic acid added to aqueous solution of amylose.
Etude de l'acidité formée au cours de l'irradiation gamma de l'amidon de maïs
Authors: Athanassiadis Par H. , Berger G. 
Published: November 2006

Study of γ Radioinduced Acidity in Corn Starch.Amounts of radioinduced acids and esters in corn starch have been measured in terms of different conditions of irradiation (dosis, dosis rate, temperature, atmosphere) and of starch characteristics (% water, impurities, kind of glucosidic link) and results have been compared to those given by heat sterilization. Subsequent development of acidity have been checked during the storage at ambient temperature.
Presence d'acide formique dans l'amidon de maïs irradié
Authors: Dauphin J. F. , Athanassiadis H. , Berger G. , Saint‐Lèbe Et L. 
Published: November 2006

AbstractPresence of Formic Acid in Irradiated Maize Starch. Formic acid occurs in relatively large amounts during gamma irradiation of maize starch (100 μg/g/Mrad, in oxygen). It represents the main part of radio‐induced free acidity. We determined the influence of several parameters: irradiation conditions (dose, dose rate, temperature, surrounding gas), storage temperature, starch characteristics (moisture, impurities), heat treatment. A formation process is prosposed.
Gamma‐Irradiated Corn Starches. Alkaline Dispersions for Surface‐Sizing Paper
Authors: Hofreiter B. T. , Russell C. R. 
Published: November 2006

AbstractCorn starch was depolymerized by gamma irradiation (cobalt 60, approximately 1.25 Mrads/h) to prepare reduced viscosity products for surface‐sizing paper. The general effects of irradiation were determined on the extent of starch degradation, as well as dispersion variables. Low levels of irradiation, 0.02 to 0.5 Mrad, had a profound influence on granule swelling and disruption at a pasting temperature of about 90°C as determined in a recording viscometer. Product properties are affected considerably by carbonyl and carboxyl groups even when introduced at levels below 1 mmol/100 g. Carbonyl groups impart alkali sensitivity that produces significant degradation during dissolution in stoichiometric quantities of alkali. Carboxyl groups in starch paper sizes are detrimental because they act as dispersants for fines and fillers in repulped paper. Apparently dispersion in alkali is the most effective way to utilize irradiated starches as surface‐sizing agents. Corn starch irradiated to 2 Mrads and dispersed in alkali improved paper properties as well as a high quality commercial product.
The Characterization of Starch and Its Components. Part 6. A Critical Comparison of the Estimation of Amylose‐Content by Colorimetric Determination and Potentiometric Titration of the Iodine‐Complex
Authors: Banks W. , Greenwood C. T. , Muir D. D. 
Published: November 2006

AbstractThis paper is dedicated to Mr. Ernst Hees, Editor of „Die Stärke”︁ from 1958 until December, 1973, as a token of the esteem with which we regard his work in this capacity. We thank him for his efforts, which have so successfully helped to advance the subject of starch chemistry in all its diverse aspects.The techniques of (i) semi‐micro, differential, potentiometric iodine titration of starch with iodine, and (ii) colorimetric assay of the starch‐iodine complex in solution have been compared as analytical tools for the measurement of the amylose‐content of starches. Although the colorimetric method may be calibrated to give comparable results to the potentiometric assay, the former technique is not applicable to maize starches of high amylose‐content.
Die dielektrischen Eigenschaften der Stärke im Mikrowellenbereich als Grundlage für die Feuchtigkeitsbestimmung
Authors: Mládek J. , Komárek K. 
Published: November 2006

AbstractDielectric Properties of Starch in the Range of Microwaves as a Basis for Determination of Humidity. The change of dielectric properties of starch with change of water content was utilized for continual determination of humidity. For that purpose, the balance method was applied, in order to measure attenuation and phase shift of the electromagnetic wave permeating the material. The 10 GHz‐microwave was generated by means of a reflex klystron. With increasing humidity there is an increase of electric loss. At the same time, the increase of attenuation of the electromagnetic wave in the starch makes possible to find the transitions between free and bound water of capillarity using a correction control circuit an accuracy in measurement of 0,3% absolute is reached.
Starch Xanthide Styrene‐Butadiene Rubbers. Effect of Prolonged Water Immersion
Authors: Buchanan R. A. 
Published: November 2006

AbstractBoth conventionally reinforced and starch xanthide reinforced styrene‐butadiene (SBR) rubbers swell continuously during water immersion without reaching equilibrium and eventually mechanical breakdown occurs. During 90 days of water immersion, starch xanthide‐reinforced SBR swells more than conventionally reinforced SBR, but much less than would be calculated from the volume fraction of starch xanthide and its swelling ratio as measured separate from rubber. Swelling rate of vulcanized starch xanthide‐SBR rubber specimens depends on their shape and is negligible for specimens with low enough surface to volume ratios. Standard tensile test specimens have low cross sections in the break area and provide a sensitive measure for the deleterious effect of prolonged water immersion. The effects after 90 days in water on both swelling and tensile properties of starch xanthide‐SBR are fully reversible by drying test specimens. Starch xanthide‐SBR masterbatch can be compounded either with reactive crosslinking and coupling agents or with low‐cost extenders and fillers to reduce greatly the effect of prolonged water immersion.
Derivatives of High‐Amylose Starch Xanthate in Rubber. Influence of Amylose Content of Starch Upon the Water Resistance of Starch‐Reinforced Styrene‐Butadiene Rubbers
Authors: Katz H. C. , Kwolek W. F. , Buchanan R. A. , Doane W. M. , Russell C. R. 
Published: November 2006

AbstractCrosslinked low‐amylose (0 or 28%) starch xanthates used as reinforcing materials in styrenebutadiene elastomer imparted better dry tensile properties than their high‐amylose (55, 68 or 82%) analogues. After immersion in water for 70h the tensile strength of low‐amylose starch reinforced vulcanizates deteriorated considerably while high‐amylose starch reinforced vulcanizates changed little or not at all. Such variables as xanthate degree of substitution and starch loading influenced curing time and properties. Mode of crosslinking the xanthate significantly affected retention of starch in the coprecipitate, and produced significant variations in curing characteristics, and in such properties as compression set, set at break before immersion in water and tensile strength after water immersion. The method of drying affected compressions set and modulus.