bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Critical Assessment of the Parameters Affecting the Official EC “Ewers” Method for the Determination of Starch
Authors: Kennedy J. F. , Stevenson D. L. , White C. A. 
Published: November 2006

AbstractThe Ewers method for the measurement of starch is currently the official EEC method for the measurement of starch purity. In this communication a critical assessment of variables affecting the Ewers method has been undertaken. It was found that the degree of hydrolytic degradation which occurs during the solubilisation of starch prior to polarimetric measurements is of crucial importance in the starch purity values obtained. Factors which influence the degree of hydrolytic degradation include hydrochloric acid concentration to a large extent, and heating and cooling times to a lesser extent. It has been shown also that the clarifing reagent of Carrez, which is used in Ewers method for the removal of other chiral molecules such as protein, etc, adsorbs lower molecular weight malto‐oligosaccharides leading to reduced starch purity values. For a series of starches with varying amylose: amylopectin ratios it was found that high amylopectin starches performed much better in Ewers method than high amylose starches. It is concluded that Ewers is not an acceptable satisfactory method for starch measurement on which to base quality control or eligibility for rebate and refund schemes.
Oxidation of Maltodextrins and Starch by the System Tungstate‐Hydrogen Peroxide
Authors: Floor M. , Schenk K. M. , Kieboom A. P. G. , van Bekkum H. 
Published: November 2006

AbstractThe potential of the aqueous system sodium tungstate‐hydrogen peroxide for glycol‐cleavage oxidation of maltodextrins, starch and trans‐1,2‐cyclohexanediol as a model compound has been evaluated. The peroxotungstate species formed in this medium effect oxidation of the glucose units via two major pathways: (i) glycol‐cleavage of the C2–C3 diol moieties in internal glucose units, followed by (undesired) hydrolysis of the ring‐opened intermediate and (ii) stepwise decarboxylation at the reducing terminal glucose unit until the glycosidic bond is reached. Both reaction types yield glucose oligomers terminated by erythronic acid at the former reducing end, which is an important fraction (up to 40%) of the oxidation product. Decomposition of hydrogen peroxide to oxygen and water is an inevitable side reaction.
Alternative Route to Non‐ammonia Caramels of High Tinctorial Strength
Authors: Sikora M. , Tomasik P. 
Published: November 2006

AbstractThe results of caramelization of highly saccharified starch syrup in the presence of α‐hydroxy and α‐amino acids and their sodium salts are presented, Sodium salt of glycine as the catalyst provides the caramel of the highest tinctorial strength.
Studies on Modified Tamarind Kernel Powder. Part I: Preparation and Physicochemical Properties of Sodium Salt of Carboxymethyl Derivatives
Authors: Prabhanjan H. 
Published: November 2006

AbstractSodium salt of 0‐carboxymethyl derivatives of tamarind kernel powder (TKP), at different levels of substitution, was prepared in iso‐propanol medium. The derivatives were characterised by degree of substitution (DS), intrinsic viscosity and elution profile (GPC). Alkaline solutions, purified by alcohol precipitation showed higher intrinsic viscosity due to an alkali soluble fraction. Solution properties of the derivatives as a function of DS were found to be affected both by the substituent groups as well as by the alkali used for derivatization. Swelling power, solubility and tolerance to organic solvents of the derivatives increased with increasing carboxymethylation. The interaction properties of TKP with calcium chloride and sodium tetraborate were found to be reversed upon carboxymethylation.
Acylierter Weizenkleber als Cobindemittel in Papierstreichfarben
Authors: Kersting H. J. , Kempf W. 
Published: November 2006

AbstractWeizenkleber kann in nativer Form aufgrund seiner strukturbedingten Eigenschaften nicht für technische Applikationen genutzt werden. Aus diesem Grunde muß der Kleber durch chemische Methoden so aufgearbeitet werden, daß er den gewünschten technischen Anforderungen entspricht. Aufarbeitungsverfahren, Einflußgrößen sowie papiertechnische Anforderungen hinsichtlich eines Einsatzes von Weizenkleber in Papierstreichfarben sind Gegenstand dieses Artikels. So konnte durch unsere Untersuchungen gezeigt werden, daß chemisch modifizierter Weizenkleber als Cobindemittel in Papierstreichfarben eingesetzt werden kann, da er in einigen wichtigen technischen Eigenschaften, wie dem Fließverhalten, der Rupffestigkeit sowie des Wasserrückhaltevermögens, sich gegenüber einem industriellen Standard‐Cobindemittel gleichwertig oder sogar teil‐weise überlegen erweist.
Enzymatic Hydrolysis of Amaranth Flour — Differential Scanning Calorimetry and Scanning Electron Microscopy Studies
Authors: De La Rosa A. P. Barba , Paredes‐López O. , Cárabez‐Trejo A. , Ordorica‐Falomir C. 
Published: November 2006

AbstractHigh‐protein amaranth flour (HPAF) and carbohydrate rich fraction (CRF) were produced from raw flour in a single‐step process using a heat‐stable α‐amylase preparation. Protein content of flour increased from 15 to about 30 or 39% at liquefaction temperatures of 70 or 90°C, respectively, and 30 min hydrolysis time. CRF exhibited 14–22 DE. Enzymatic action at 70°C increased endotherm temperatures and gelatinization enthalpy of HPAF, in relation to gelatinized flour, as assessed by differential scanning calorimetry (DSC). Hydrolysis at 90°C did not affect significantly (P > 0.05) DSC peak temperature. It is suggested that these changes in DSC performance might result from differences in amount and type of low‐molecular weight carbohydrates and residual starch. Scanning electron microscopy (SEM) demonstrated that hydrolysis temperature changed substantially the structural appearance of flour particles. HPAF and CRF might find applications as dry milk extender and sweetener, respectively.
Some Properties of Amaranthus paniculatas (Rajgeera) Starch Pastes
Authors: Singhal Rekha S. , Kulkarni Pushpa R. 
Published: November 2006

AbstractThe lysine rich high protein seeds of A. paniculatas (Rajgeera) are reported to contain 50–60% of waxy starch, concentrated in the endosperm. However its food related properties are comparatively unknown. In the present work, paste viscosity, paste clarity, freeze‐thaw stability and effect of shear on the viscosity of A. paniculatas starch paste have been studied and compared to corn starch. Also included are the stability of Rajgeera starch paste under pressure cooking (30 min, 15 lb pressure) and acidic conditions (pH 6.98—1.76). Rajgeera starch was found to have a higher paste viscosity, lower paste clarity and high freeze‐thaw stability than corn starch. Both Rajgeera and corn starch underwent thinning on being subjected to mechanical shear. Rajgeera starch withstood pressure cooking conditions admirably, but was found to be sensitive to acidic conditions.
Crystallinity of Raw Rice Starch Granules as Indexed by Corrosion with Hydrochloric Acid and Amylase
Authors: Juliano B. O. , Perez C. M. 
Published: November 2006

AbstractAfter 15 d in 2.2N HCl at 35°C, residual starch of 34 granular rice starches differing in apparent amylose content (AC) and final gelatinization temperature (GT) ranged from 1.3 to 20.8% and was verified to correlate significantly with GT (r = 0.69**) and AC (r = 0.44**). Residual starch after 5 h corrosion with crude Chalara paradoxa amylase ranged from 0 to 29.4% and also correlated significantly with GT (r = 0.45**) and AC (r = 0.70**). The amounts of residual starch after Lintnerization and after C. paradoxa amylase digestion were significantly correlated (r = 0.72**).
Influence of Monoglycerides of Different Chain Lengths on Texture and Flavor of Breads Made with Waxy Cornstarch
Authors: Hartunian‐Sowa S. M. , White P. J. , Batres L. V. 
Published: November 2006

AbstractThe addition of monoglycerides (MGs) monolaurin (ML), monomyristin (MM), monopalmitin (MP), and monostearin (MS)) to a model system bread made from waxy cornstarch was studied for their effects on delaying staling. The model system breads containing 0.5% of a MG and a control bread containing no MG were prepared five different times and stored at room temperature for 1, 3, and 6 days. A sensory panel measured changes in firmness, stale flavor, and moistness, and an Instron universal testing machine (model 1122) was used to indicate firmness of the samples. The volumes of the loaves were measured on day 1 for the five replications. Results indicated that the addition of MGs to the model system breads decreased firmness and stale flavor and increased moistness compared with the control bread. Breads containing MM and MP were rated significantly (p<0.05) less firm and less stale on days 1 and 6 and more moist on day 1 than the breads containing MS and the control bread. In general, as the molecular weight (MW) of the MGs increased, the firmness (by Instron) of the breads also increased, and the volume of the loaves decreased. The control bread had the highest Instron firmness value and the lowest volume when compared with the breads containing MGs.
Studies on Mutagenicity of Caramel
Authors: Barabasz W. , Brzózka Ł. , Krzeczek J. , Tomasik P. 
Published: November 2006

AbstractCaramels laboratory‐prepared by thermolysis of pure α‐D‐glucose, D‐fructose and sucrose as well as of these sugars with some nitrogen‐containing and nitrogen‐free catalysts were tested against Escherichia coli strains. These caramels exhibit free‐ radical character independently of the mode of their preparation. Biological functions of Escherichia coli in 10 subsequent generations grown without caramel and with caramel added to a nutrient broth were tested in a standard scope of 15 biological tests. Neither growth nor biological functions of all generations of this bacterium were influenced by caramels added.
Halbkornmethode zur Bestimmung des Amylosegehalts in Gerste
Authors: Schwank U. , Jacobi A. , Drawert F. , Fischbeck G. 
Published: November 2006

AbstractFür die pflanzenzüchterische Nutzung von Amylosemutanten ist eine Methode, die den Amylosegehalt eines Einzelkorns messen kann, von Bedeutung. In der vorliegenden Arbeit wird eine potentiometrische Titration zur Amylosebestimmung an einem halben, reifen Gerstenkorn beschrieben und die Auswertung der Titrationskurven diskutiert. Mit Hilfe der dargestellten Methode gelingt eine Einteilung verschiedener Gerstensorten und ‐linien in Genotypen mit unterschiedlichem Amylosegehalt.
Studies on Applicability of Amaranthus paniculatas (Rajgeera) Starch for Custard Preparation
Authors: Singhal R. S. , Kulkarni P. R. 
Published: November 2006

AbstractA. paniculatas or Rajgeera has been shown to contain 50–60% of waxy starch, having an extremely small granule size of 1–2 μm, and higher paste viscosity than corn starch. Studies on utilisation of Rajgeera starch for custard preparations showed it to be unsuitable for such purpose because of interactions among the various ingredients used in the formulation.
Production of Cyclodextrins by Simultaneous Actions of Two CGTases from Three Strains of Bacillus
Authors: Kaneko Takahiro , Yoshida Masahiro , Yamamoto Mikio , Nakamura Noboyuki 
Published: November 2006

AbstractA moderate thermophile, which produces a large amount of extracellular and thermostable cyclomaltodextrin glucanotransferase, was isolated from soil samples at hot spring areas in Japan. The isolate (A‐147), that grew at 30–60°C with an optimum at 45–50°C, was identified as a strain of Bacillus coagulans. The enzyme, which was most active at pH 6.5 and 60°C, was stabilized by 2–3 mM Ca2+, and degraded about 40% (as dry basis) of 13% (w/w) potato starch solution into cyclodextrins composed of α‐ and β‐cyclodextrins dominantly at 74°C and pH 6.5 in the presence of 3 mM Ca2+. The ratio of α‐, β‐ and γ‐cyclodextrins was almost constant (2:2.6:1) during all stages of the reaction. By simultaneous actions of two enzymes from the bacterium and other 2 kinds of Bacillus, starch hydrolysates containing various amounts and rations of cyclodextrins were produced from starch.Ein mäßiges Thermophiles, das eine große Menge an extracellulärer und thermostabiler Glucanotransferase produziert, wurde aus Bodenproben in Heißquellengebieten von Japan isoliert. Das Isolat (A‐147), das bei 30–60°C mit einem Optimum von 45–50°C wuchs, wurde als ein Stamm von Bacillus coagulans identifiziert. Das bei pH 6,5 und 60°C aktivste Enzym wurde durch 2–3 mM Ca2+ stabilisiert und baute etwa 40% (TS) einer 30%igen (w/w) Kartoffelstärkelösung zu Cyclodextrin ab, bestehend aus α‐ und β‐Cyclodextrin, vorwiegend bei 74°C und pH 6,5 in Gegenwart von 3 mM Ca2+. Das Verhältnis von α‐, β‐ und γ‐Cyclodextrinen war nahezu konstant (2:2,6:1) während sämtlicher Reaktionsschritte. Durch gleichzeitige Einwirkung von zwei Enzymen aus dem Bakterium und zwei anderen Arten von Bacteria wurden Stärkehydrolysate hergestellt, die verschiedene Mengen und Verhältnisse an Cyclodextrinen enthielten.
Two‐Dimensional Nuclear Magnetic Resonance Studies of Starch and Starch Products
Authors: McIntyre Deane D. , Vogel Hans J. 
Published: November 2006

AbstractThe use of two‐dimensional Nuclear Magnetic Resonance (NMR) spectroscopy as applied to studies of starch, starch products and glycogen is reported. The use of both homonuclear correlation (COSY, relay‐COSY and HOHAHA) and heteronuclear correlation (HMQC, HETCOR) experiments is discussed. This approach makes it possible to obtain complete assignments of the proton NMR spectra of these polysaccharides. This is not possible from 1‐D spectra due to excessive overlap of the non‐anomeric proton signals. The resulting assignments are useful in obtaining structural information regarding starch and related products. Moreover, the greater inherent resolution of the two‐dimensional spectra can reveal the presence of low molecular weight carbohydrates (glucose, maltose etc.) in dextrin samples, thus providing information about carbohydrate composition.
Subsite Structure of Rhizopus niveus Glucoamylase, Estimated with the Binding Parameters for Maltooligosaccharides
Authors: Ohnishi Masatake 
Published: November 2006

AbstractBased on Kd and Ki for maltosaccarides Gn (n = 1 ± 7) and on a specified mode of their binding, the intrinsic affinities A1, A2, –, Ai at subsites i (i = 1 ± 5), were tried to estimate for glucoamylase from Rhizopus niveus. Previously, we have evaluated the apparent values Ai using Km and k0 on the enzyme‐catalyzed hydrolysis for Gn, where A1 is nearly 0 kcal/mol. Thus A1, which was found here 3.3 kcal/mol, may be cancelled out with the heat, which is consumed for the hydrolytic cleavage of a substrate glucosyl bond.
Kinetic Characterization of Chimeric Cyclomaltodextrin Glucanotransferase from Genes of Two Alkalophilic Bacillus
Authors: Kaneko Takahiro , Nakamura Nobuyuki , Horikoshi Koki 
Published: November 2006

AbstractThe chimeric CGTase, which was constructed genetically with two β‐CD forming type enzyme genes of different species of alkalophilic Bacillus, was characterized by comparing with the actions of parent enzymes. The final composition of CDs in the reaction digest from starch by the chimeric enzyme, especially in the yield of α‐CD, was different from those by parent enzymes, and total yields of CDs by these enzymes were almost the same. The chimeric enzyme catalyzed the formation of β‐CD as a major action from starch, the rapid synthesis of α‐CD from other CDs and maltooligosaccharides and the slow degradation and interconversion of α‐CD to others. From these results, the role of second and third segments in the enzyme molecules was discussed.
An Electron Diffraction Study on Whole Granules of Lintnerized Potato Starch
Authors: Chanzy Henri , Vuong Roger , Jésior Jean Claude 
Published: November 2006

AbstractPotato starch granules which had been lintnerized for 10 d in 2.2 N HCL at 35°C, embedded in Nanoplast and cross sectioned with a low angle diamond knife having an angle of 33.7° have been studied by electron diffraction. The sections were apparently defect free. When they were surveyed under frozen hydrated conditions by transmission electron microscopy in diffraction mode, they gave electron diffractograms typical of B starch. Central sections gave fiber diagrams, whereas noncentral or tangential sections gave strongly arced or even continuous ring diagrams. This technique, if it can be extended to other starch systems, will enable more detailed studies to be made of the crystalline ultrastructure of starch and the organization of the amylose fragments within the starch granule.
The Combined Effect of Oxidation and Carbamoylethylation on the Rheological Properties of Maize and Rice Starches
Authors: Ragheb A. , Refai R. , El‐Thalouth I. Abd , Hebeish A. 
Published: November 2006

AbstractThe combined effect of oxidation and etherification on the molecular structure of starch was investigated. Maize and rice starches were used. Oxidation was effected using sodium hypochlorite while etherification was performed by reacting starch with acrylamide in presence of sodium hydroxide; this reaction is known as carbamoylethylation. The extent of the latter, expressed as % N, was found to increase by decreasing the molecular size of starch through oxidation. The carbamoylethyl starches so obtained could be precipitated by ethanol and they are soluble in water irrespective of the kind of starch. On the other hand, results of rheological properties indicated that they are governed mainly by the molecular size of starch. Oxidized starches with relatively high molecular size exhibit thixotropic behaviour. The degree of thixotropy decreases and changes into pseudoplasticity as the molecular size of starch decreases. The results also indicated that at constant rate of shear the apparent viscosity of carbamoylethyl starches decreases as the molecular size decreases. Furthermore, the rheological properties of carbamoylethyl starch pastes undergo considerable changes and so does the apparent viscosity when these pastes were stored for 3 days.
Lipids and Rheological Properties of Starch. Part II: The Effect of Granule Surface Material on Viscosity of Wheat Starch
Authors: Nierle W. , El Bayâ A. W. , Kersting H. J. , Meyer D. 
Published: November 2006

AbstractThe extraction of wheat starch with ethanol reduced the protein content from 0.4 to 0.3%. Wheat starch extracted with 1% SDS containing 1% 2‐ME or with 1% SDS gave no staining with amido black, indicating that most of starch surface protein has been separated. TLC of lipids extracted from starch without gelatinization showed that ethanol extracted considerable amounts of starch lipids such as lysophosphatidyl choline, lysophosphatidyl ethanolamine and free fatty acids. After extraction with SDS and especially with SDS + 1% 2‐ME only some starch granules were deformed. In this starch some changes have been observed also on the granules surface by REM. The extraction resulted also in considerable changes in rheological properties of extracted starches. The starch samples were characterized thermodynamically also.
Effects of Nixtamalization and Grinding Conditions on the Starch in Masa
Authors: Gomez Marta H. , Waniska Ralph D. , Rooney Lloyd W. 
Published: November 2006

AbstractStarches from corn and sorghum masas were solubilized in water and their molecular characteristics were studied with high‐performance, size‐exclusion chromatography (HPSEC). Rheological properties of masa (smoothness, plasticity and cohesiveness) that are developed during lime‐cooking, steeping and grinding of cereals were correlated to the starch solubility. Corn and sorghum were processed at different cooking times and grinding conditions; and the starch in masa was extracted with water at 85°C and 120°C for HPSEC analysis.Starches from corn and sorghum masas were affected in a similar way by the nixtamalization process; however, sorghum starch was more soluble than corn starch in flour and masa. Alkaline‐cooking, steeping and stone‐grinding did not depolymerize the cereal starch. All masas contained less than 10% soluble solids of which 30 to 50% was starch solubilized. Soluble solids increased with longer cooking time and finer grinding. About 50% of the insoluble starch, which remained in the particulate solids of masas was solubilized in water at 120°C. The remaining starch was indispersible because either the starch remained inside endosperm pieces or inside gelatinized and retrograded gels.Several granular and molecular forms of starch were present in masa as a result of partial gelatinization, i.e. uncooked, swollen, and annealed starch granules, and soluble and retrograded amylose. Retrogradationo f starch polymers occurred during steeping of cooked corn and during cooling of masa after grinding. Masa, a unique dough system, resulted from a network of starch polymers, uncooked and partially gelatinized starch granules supporting the rest of the kernel components into a continuous phase of water.
Kinetic Properties of the Rhizopus Glucoamylase and Bacillus α‐Amylase, which are Immobilized on Cellulofine
Authors: Ohnishi Masatake , Iwata Ken , Tomita Takayo , Nishikawa Ukiko , Hiromi Keitaro 
Published: November 2006

AbstractGlucoamylase from Rhizopus niveus was immobilized on Cellulofine, a kind of cellulose gel, to construct an enzyme‐Cellulofine structure, of which the molar activities k0 for maltose and for soluble starch were found almost equal to 4 and 1/9 times, respectively, of those found with the intact enzyme. Liquefying Bacillus α‐amylase was fixed to make another enzyme‐Cellulofine structure, of which ratio of the molar activities, k0 (modified)/k0 (intact) for an oligomer substrate maltohexaose is much larger than those for high‐polymer substrates, amylose and soluble starch. These findings suggest that the substrate specificity of the amylase‐Cellulofine structure is improved to be useful for the enzyme‐catalyzed hydrolysis of saccharides having small degree of polymerization.
Synthesis of Thermostable Alpha‐Amylase by Bacillus Isolate R–8
Authors: Jamuna R. , Ramakrishna S. V. , Bindu C. 
Published: November 2006

AbstractAn indigenous isolate Bacillus R–8 was found to produce thermostable β‐amylase. The enzyme yield was highest during the stationary phase of the culture. Maximum production of 100 units per ml was achieved in the maltose medium and also in the alkaline conditions of fermentation. It has been observed that the rate of enzyme formation was highest (2.8 units/g of cells/h) with glucose under neutral conditions. The variations in the fermentation parameters which have resulted in the significant difference in terms of total enzyme production and the rate of enzyme formation have been discussed.
Studies on Semi‐technical Separation of Mung Bean Starch
Authors: Haase Norbert U. , Tegge Günther , Thu Nguyen Manh 
Published: November 2006

AbstractStarch of mung beans is the raw material for high grade glass noodles, but until now industrial starch separation is often less efficient. For testing new fields of commercial use it is of benefit to experiment with very pure starches. Regarding this, possibilities of starch isolation on a semi‐technical scale are described, which resulted in most pure starches. Crude protein content could be lowered down to 0.3% and crude fibre content down to 0.5% dry matter base.