bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of Pinhao Starch. Part III: Hydration of the Granules and Susceptibility to Enzymatic Hydrolysis
Authors: Wosiacki G. , Grossa P. , Cereda M. P.
Published: November 2006

The granules of the starch isolated from pinhao showed a higher cold water binding capacity as compared to the values found for the starch granules from corn and from cassava. The swelling power and the solubility of pinhao starch granules, studied in the temperature range 65 to 95°C showed some similarity with that of corn starch granules. Enzymatic treatment under cold conditions was unable to disrupt their granular integrity. As observed by viscometric analysis, however, in the temperature range 50 to 95°C, pinhao starch granules showed higher susceptibility to amylolytic attack than corn starch granules, reaching the same level of viscosity decrease observed for cassava starch granules.
Electron Microscopic Study of Products Containing β‐Cyclodextrin
Authors: Hódi K. , Aigner Z. , Fahr F. , Kata M.
Published: November 2006

The advantageous properties of cyclodextrin (CD) derivatives have been applied in various fields of drug production. Their presence in physical powder mixtures increases the flow characteristics, which can be improved still further if isodimensional particles and homogeneous dispersive products are produced by spray‐embedding. An account is given of an electron microscopic study of such products.
Preparation of Crosslinked Starch Beads as a Medium for Gel Filtration
Authors: Chaudhari M. R. , Kamath N. D. , Bhide S. V. , Kale N. R.
Published: November 2006

Potato starch is dispersed in sodiumhydroxide and fine emulsion is obtained by stirring in liquid paraffin at 80°C. The emulsion is crosslinked with epichlorohydrin in presence of sodium borohydride to obtain thermostable beads. Beads of uniform size were obtained by sedimentation under gravity. Mixtures of proteins such as bovine serum albumin (BSA) and cytochrome c can be separated on columns (Ø 2.5 × 25.0 cm) packed with these beads. The elution profiles are similar to that of Sephadex G‐100.
Effects of Aliphatic Alcohols on Formation of Cyclodextrin from Soluble Starch by Bacillus macerans Cyclodextrin Glucanotransferase
Authors: Shiraishi Fumihide , Kawakami Koei , Marushima Hiroshi , Kusunoki Koichiro
Published: November 2006

Effects of aliphatic alcohols such as ethanol, n‐butanol and n‐decanol on the formation of cyclodextrin (CD) from soluble starch by Bacillus macerans cyclodextrin glucanotransferase (CGTase) were experimentally studied at 50°C and pH 6.0. The addition of such aliphatic alcohols caused an increase in α‐CD yield, which extent was remarkable in n‐butanol. From the incubation of α‐CD with CGTase, such an increase was found to be due to a restriction on further transglycosylation of α‐CD into β‐CD by CGTase imposed by the aliphatic alcohols.
Solubility of Maltose in Water in the Presence of Glucose and Maltotriose
Authors: Schartges D. , Berglund K. A.
Published: November 2006

Maltose is used in various forms in the food and pharmaceutical industries. Maltose syrups produced by enzymatic starch conversion usually contain impurity sugars, e.g. glucose, maltotriose, and higher saccharides, which affect the solubility of maltose. Using a simple refractometric technique, solubility data for the pure and impure maltose systems were determined. Glucose and maltotriose were found to decrease the equilibrium concentration of maltose but increase the total dissolved solids concentration.
A Study of Factors Affecting Amylose Content of Sorghum Determined by an Automated Method
Authors: Ring S. H. , Akingbala J. O. , Rooney L. W.
Published: November 2006

Several factors affecting the amylose content of sorghum, as determined by an automated iodine‐blue complex method, were evaluated. Isolation of starch reduced the optimum solubilization time of the endosperm starch by 36 h. Amylose as % of isolated starch was significantly greater than amylose as % in the endosperm. However, amylose as % of starch in endosperm (“apparent” amylose content) was highly significantly correlated (r = 0.79) with amylose as % of isolated starch (“true” amylose content) that it could be used for screening sorghum in a breeding program. Pericarp and testa colors significantly affected the measurable amylose of unpearled sorghum flour. The environment of growth and maturation of the grain also affected the amylose content of sorghum.
Development of an Alternate Route for the Hydrolysis of Cassava Flour
Authors: Abraham T. Emilia , Sreedharan V. P. , Ramakrishna S. V.
Published: November 2006

Moldy wheat bran as such is used as a source of amyloglucosidase enzyme (EC 3.2.1.3) in the hydrolysis of cassava flour. 92–94% of glucose was obtained in the hydrolysate after 16 h of hydrolysis. The process was found to be economical compared to the hydrolysis using commercially available liquid enzymes.
An Objective Illustration of the Inadequacy of the Official EC “Ewers” Method for the Determination of Starch
Authors: Kennedy John F. , Stevenson David L. , Junel Kornelia
Published: November 2006

The Ewers method for starch determination is currently the Official EEC method for measurement of starch purity. In this communication we demonstrate that the use of trifluroacetic acid for solubilisation of starch prior to polarimetric measurements is preferred over the use of mineral acids since the degree of hydrolytic degradation observed with this reagent was minimal compared to mineral acids, thereby giving improved starch purity values. Of particular concern we demonstrate that the Ewers method is non‐specific in that the addition of an epichlorohydrin cross‐linked dextran as an adulterant enhances the value of starch purity obtained. The Ewers method however was able to detect agarose and carboxymethyl cellulose added to starch as adulterants.

It is concluded that the Ewers method is not an acceptably satisfactory method for starch purity measurement on which to base quality control or eligibility for rebate and refund schemes.
Toward a New Generation of Glucose Isomerases Through Genetic Engineering
Authors: Sicard P. J. , Leleu J.‐B. , Tiraby G.
Published: November 2006

Streptomyces violaceoniger glucose isomerase (GI) was originally developed in 1973 when expectations about the future of HFCS in Europe were great. Improvement of the original strain CBS 409—73 obliged to consider the possible utilizations of genetic engineering as the best possible way for obtaining hyperproduction of the enzyme. The structure gene of GI was cloned and transferred in an integrating plasmid PUT 220 derived from pIJ 702. The sequence of the gene was determined and compared to the aminoacid sequence of the purified glucose isomerase. Crystallization of the enzyme was achieved and its 3‐D structure established; S. volaceoniger GI is normally existing as a tetramer with 4 identical sub‐units of 388AA each. The monomer includes a (alpha‐beta) 8 barrel sub‐structure and a large hydrophobic loop involved in the formation of dimers. Simultaneously, structural analysis of S. olivochromogenes GI revealed a great similitude with S. violaceoniger GI, though the former could exist as a dimer.

In view of this situation and considering that because of a high level of homology, both enzymes presented significant differences in their functional properties, hybrid molecules were constructed and site directed mutagenesis utilized to create new GI species with modified properties.
Purification and Properties of Inulinase from Arthrobacter globiformis S64—1
Authors: Haraguchi K. , Hayashi K. , Kasumi T.
Published: November 2006

A bacterium, Arthrobacter globiformis S64—1, produced an inulinase in the culture broth. The enzyme was purified 442‐fold by DEAE‐Toyopearl chromatographies. It showed maximal activity at 40°C and pH 6.5. The enzyme activity was inhibited strongly by Hg2+, Fe3+, Cu2+ and EDTA. The molecular weight of the enzyme was estimated to be 100,000 by SDS‐PAGE. The isoelctric point of the enzyme was estimated to be 4.8 by isoelectric focusing on a polyacrylamide gel. The enzyme degraded inulin through an exo‐type reaction.
Dibenzalsorbitol as an Example of Sucrochemistry from Sorbitol
Authors: Flèche Guy
Published: November 2006

Whereas its renewable source, vegetal carbon will trend more and more to be considered as a starting raw material for organic synthesis. Although cellulose is proportional the first in volume, starch shows the most industrial development to versatile polymers and molecules due to chemical and biochemical conversions. However, chemistry of saccharides and polyols is made tedious because of the polyfunctionality. This last point leads to a specific reactional strategy built up with protection of reactional groups. Time‐consuming and uneconomical steps have sometimes dissuaded industrial researchers from developing new molecules. So, development of new synthetic routs and catalysts with specific separation tools will open the door to a new generation of products comming from sucrochemistry, with better yields and improved selectivity. In order to illustrate this new way, acetalisation of sorbitol with benzaldehyde has been chosen. An inverse phase transfer catalysis (PTC) is used and comparison with a traditional catalysis is made. After reviewing different operational factors, emphasize is put on the highest selectivity obtained with a PTC.
Glucose Production from Maltohexaose as a Substrate by the Bacterial Alpha‐amylase‐catalyzed Reaction. Its Time Courses Obtained by a Theoretical and an Experimental Approaches
Authors: Iwata Ken , Ohnishi Masatake , Hiromi Keitaro
Published: November 2006

Based on the subsite structure of an α‐amylase from Bacillus subtilis, production of glucose from a substrate maltohexaose in the amylase‐catalyzed reaction was theoretically predicted as a function of time. The theoretical time course was found consistent with the experimental results, which were obtained by the determination of a product glucose with a commercial assay‐kit. Hence, glucose, product from a substrate maltohexaose, will be a useful probe for the amylase‐catalyzed reaction.
Cereal Grains: A Study of Their α‐1,4‐α‐1,6 Glucopolysaccharide Composition
Authors: Curá José A. , Krisman Clara R.
Published: November 2006

The glucopolysaccharides containing α‐1,4 and α‐1,6 linkages present in the endosperm of mature cereal seeds (corn, wheat and rice) were fractionated according to their branching degree. An already published method [19] was used to specifically estimate the α‐1,6 linked glucoses involved in the branching points. The following features were found:

a) Starches from different tissues vary in their relative amount of amylose and amylopectin. b) Amylose is present either as a strictly linear or additionally as a lowly branched polysaccharide. c) Amylopectins with a rather wide range of branching degrees were detected. A redefinition of the starch α‐1,4—α‐1,6 glucopolysaccharides based on their λmax and percentages of glucoses in branching points was introduced. A linear correspondence between brauching points and the maximum absorption (λmax) in the presence of Krisman's iodine reagent was obtained.
Eigenschaften und Anwendungsmöglichkeiten von Erbsenstärken. Teil 1: Eigenschaften
Authors: Stute R.
Published: November 2006

Während Erbsen und Erbsenmehle seit Jahrtausenden Bestandteil der menschlichen Ernährung sind, bemüht man sich erst seit wenigen Jahren um die Gewinnung von Erbsenstärken. Besonders interessant ist der im Vergleich zu den üblichen Stärken höhere und einen Bereich von 30% bis über 90% abdeckende Amylosegehalt der Erbsenstärke. Industriell hergestellt wird bisher nur die glatte, rund‐ovale Körner aufweisende Palerbsenstärke (Amylosegehalt 32–37%). Bei den Markerbsen (Amylosegehalt >46%) sind viele der technischen Schwierigkeiten bei der Stärkegewinnung auf die Form und den Aufbau der Stärkekörner zurückzuführen. Typisch für Erbsenstärken sind eine höhere Säure‐, Enzym‐ und Scherstabilität und ein erhöhtes Gelbildungsvermögen. Trotz eines nur wenig verschiedenen Amylosegehaltes bestehen gerade auch in bezug auf diese Eigenschaften sowie bezüglich Viskosität und Gelbildung große Unterschiede zwischen den bisher industriell in Kanada bzw. Dänemark hergestellten Palerbsenstärken.
Eigenschaften und Anwendungsmöglichkeiten von Erbsenstärke Teil 2: Anwendungsmöglichkeiten
Authors: Stute R.
Published: November 2006

Die Anwendungsmöglichkeiten von Erbsenstärken ergeben sich weitgehend aus ihren spezifischen Eigenschaften. Wie viele Stärken mit einer Kornstruktur vom C‐Typ besitzen diese Stärken ein begrenztes Quellvermögen, das parallel läuft mit einer erhöhten Scher‐, Enzym‐ und Säurestabilität. Darüber hinaus liegt auf Grund des im Vergleich zu anderen industriell hergestellten Stärken höheren Amylosegehaltes eine deutlich erhöhte Gelbildungsneigung vor. Auf Basis dieser charakteristischen Eigenschaften zeichnen sich die folgenden Anwendungen ab:

Die Herstellung von Gelen (z. B. Puddingen), für die im Vergleich zu Maisstärke 50% weniger Stärke benötigt wird.

Die Verwendung im Extruder zur Herstellung extrudierter Produkte oder Instant‐Stärken, wobei der bei anderen Stärken auftretende signifikante Viskositätsverlust bei Erbsenstärken nicht auftritt.

Für die Herstellung von Quellstärken oder von Frucht‐ und Gemüseflocken, die nach Rehydratation eine pülpige Textur aufweisen und die eine beträchtliche Stabilität auch noch bei Kochtemperatur besitzen.

Für die Herstellung von pülpigen Produkten unter Anwendung der Schwammtechnologie (Einfrieren, Auftauen). So hergestellte Produkte verlieren auch nach längerer Kochzeit ihre pülpige Textur nicht.

Für die Produktion von Quellstärken mit gelbildenden Eigenschaften, die als solche oder für die Herstellung verschiedener Instant‐Desserts mit einer flanartigen Textur Verwendung finden können.

Auf Grund der Tatsache, daß Erbsenstärken sich deutlich von den traditionellen Stärken (Mais, Weizen, Kartoffel, Tapioka) unterscheiden, ist es sehr wahrscheinlich, daß weitere Anwendungen gefunden werden, doch wie bei allen neuen Rohstoffen können neue Einsatzmöglichkeiten nur über entsprechend intensiv betriebene Anwendungstests gefunden werden, was erfahrungsgemäß einiger Zeit bedarf.
Physico‐Chemical Characteristics of Starches from Sal (Shorea robusta) and Dhupa (Vateria indica) Seeds
Authors: Tharanathan R. N. , Reddy G. Changala , Muralikrishna G.
Published: November 2006

Pure, white starches were isolated in ∼30% yields from defatted sal and dhupa meals. Both starches consisted of granules of varying size and shape characteristics, and contained considerable amounts of protein and lipid constituents. C 18:1, C 16:0 and C 18:0 were the major fatty acids present in both free and bound lipid fractions; whereas the latter in addition contained C 18:2 (∼20%). Both starches exhibited two‐stage swelling in water; for sal starch the solubility was markedly lower but its swelling power was considerably higher. In DMSO the sal starch was readily soluble but not dhupa starch (only ∼20% solubility). The hot paste viscosity as well as set back viscosity of dhupa starch was much higher in comparison to those by sal starch. Very highly purified sal starch virtually exhibited no hot paste viscosity, and behaved like amylopectin‐rich material. The latter had only 1.5% amylose as against of ∼24% in original sal starch. X‐Ray powder patterns revealed sal starch to be of A‐type and dhupa starch to be of B‐type. Both the starch granules were susceptible for in vitro attack by human salivary α‐amylase.
Untersuchungen zur Amylosebestimmung in proteinreichen Stärkerohstoffen, insbesondere Erbsen
Authors: Haase Norbert U. , Kempf Wolfgang
Published: November 2006

Die beabsichtigte Nutzung amylosereicher Stärkearten erfordert verschiedene Formen der Amylosebestimmung. Neben exakten Laboratoriumsverfahren sind dabei einfach durchführbare Tests relevant. Da die Leguminosenstärken diesbezüglich kaum untersucht worden sind, wurde zunächst die Genauigkeit der amperometrischen Iodtitration überprüft. Daran schloß sich die Entwicklung einer vereinfachten Aufarbeitung an. Für Routinekontrollen wurde die Eignung eines adaptierten Schnelltests im Vergleich zu Ergebnissen der Iodtitration ermittelt.
5‐Hydroxymethylfurfural (HMF). A Review Focussing on its Manufacture
Authors: Kuster B. F. M.
Published: November 2006

The acid‐catalysed dehydration of hexoses results in the formation of 5‐hydroxymethylfurfural (HMF). Fructose and inulin are especially good starting materials. A review is given of the many methods to produce HMF. The reaction kinetics are dealt with in the sections: raw material, hydrolysis and reversion, catalysts, reaction temperature and time, the concentration and the risk of polymerization and the solvent and HMF stability. Manufacturing processes are illustrated for fructose as the starting material: aqueous systems with homogeneous acid catalysis or those using ion‐exchangers as catalyst, systems using dimethyl sulfoxide as the solvent and those using other organic solvents. A short treatment is given on processes starting with glucose, work up procedures and the formation of levulinic acid and otherin situ‐formed HMF‐derivatives.
Systemanalytische Betrachtung der Derivatisierung von Stärke mit einem Kochextruder als Reaktor
Authors: Meuser Friedrich , Gimmler Norbert , Oeding Jens
Published: November 2006

Es wird eine methodische Vorgehensweise vorgestellt, mit der die systemanalytische Untersuchung des Einflusses der Extrusionsbedingungen auf den Verlauf der Derivatisierung von Kartoffelstärke zu kationischer Stärke und zu Carboxymethylstärke untersucht wird. Die Vorgehensweise lehnt sich an eine für die Extrusion von Stärke und stärkehaltige Rohstoffe entwickelte systemanalytische Betrachtung des Extrusionsvorgangs an. Mit Hilfe von Regressionsrechnungen wird gezeigt, daß auch bei der Derivatisierung der Stärke ein funktionaler Zusammenhang zwischen den Prozeß‐ und den wichtigsten Systemparametern (Produkttemperatur, spezifische mechanische Energieeinleitung, mittlere Verweilzeit) besteht. Mit diesen drei Systemparametern allein kann jedoch der Zusammenhang zwischen den Systemparametern und den Strukturparametern, wobei hier insbesondere der Wirkungsgrad der chemischen Reaktion (R. E.) als bedeutender Strukturparameter untersucht wurde, nicht beschrieben werden. Eine Korrelationsrechnung mit dem Wassergehalt als viertem Systemparameter resultierte in einer hinreichend genauen Beschreibung der funktionalen Beziehung zwischen den Systemparametern und der R. E., von welcher der Substitutionsgrad direkt abhängt. Diese vierdimensionale Abhängigkeit läßt sich jedoch graphisch nicht darstellen. Deshalb wurde die weiterführende systemanalytische Betrachtung zunächst unter der Voraussetzung eines konstanten Wassergehalts durchgeführt. Im Sinne des beschriebenen systemanalytischen Modells wurde als exemplarische physikalisch‐chemische Eigenschaft der durch Extrusion hergestellten Derivate die Kaltkleisterviskosität (KKV) in die Betrachtung miteinbezogen. Mit dem Ziel, Extrusionsbedingungen zu finden, die eine maximale R. E. ermöglichen, wurde die graphische Darstellung der Abhängigkeit der R. E. von den Systemparametern über das untersuchte Versuchsfeld hinaus extrapoliert. Kontrollversuche zeigten jedoch, daß die erhaltenen Regressionsgleichungen die Verhältnisse außerhalb des untersuchten Bereiches nicht hinreichend genau beschrieben.
Gelatinization of Starch During Preparation of Indian Unleaved Flat Breads
Authors: Sidhu Jiwan S. , Seibel Wilfried , Meyer Dietrich
Published: November 2006

The comparison of starch granule deformation and extent of starch gelatinization in a few common Indian unleavened flat breads (Chapati, Parontha and Poorie) was made. The starch granule swelling was evaluated by scanning electron as well as polarized light microscopy. The peak viscosity in Haake rotary viscosimeter and hydration capacity were used for comparing the extent of starch gelatinization in crust and crumb of these baked products. Although a few of the starch granules on the outside of crust, maintained a weak outline those in the crumb area gave only a matrix of gelatinized starch. The extent of starch gelatinization was reflected by the related increase in hydration capacity of these products. However, the peak viscosity values were found to be inversely related to the extent of starch gelatinization. As compared to crumb, a higher extent of browning was observed in the crust. Water absorption, type of cereal, mode and efficiency of heat transfer were found to control the extent of starch gelatinization in these baked products.
Glucoamylase Biosynthesis by Cells of Aspergillus niger C58‐III Immobilized in Sintered Glass and Pumice Stones
Authors: Fiedurek J. , Lobarzewski J.
Published: November 2006

A simple method of A. niger C58‐III cell immobilization is described. This strain produces extracellular glucoamylase. According to the proposed method A. niger spores were first immobilized by adsorption in sintered glass Rasching rings (RR) or pumice stones (PS). Growing out from spores, A. niger cells produced extracellular glucoamylase. This technique facilitates the culture growth in a filamentous spongy structure of the supports with a continuous accumulation of biomass. After every 24 h it was possible to obtain culture liquid rich in glucoamylase. This procedure can be repeated 30 times using the same sample of immobilized A. niger culture without any loss of glucoamylase activity in the liquid medium. In a 96 h period immobilized A. niger cells produced 300 units × ml−1 whereas a shake culture of this fungus produced only 186 units × ml−1.
Rheological Behaviour of Thixotropic Starch and Gelatin Gels
Authors: Djaković L. J. , Sovilj V. , Milošević S.
Published: November 2006

Thixotropic behaviour of starch, gelatin and mixed starch/gelatin gels was investigated by different rheological methods by means of the rotational viscosimeter with coaxial cylinders. Influence of different factors (gel composition, preparation temperature, gel age, homogenization and viscosimeter rotor acceleration) on the coefficients of thixotropy and parameters of the flow equation was considered. The recovery of destructed gels was followed by Doherty‐Hurd method, but also a modified method was developed and applied for determination of some specificities in the rheological behaviour of starch and gelatin gels.
Physicochemical Properties of Canna edulis Starch — Comparison with Maize Starch
Authors: Soni Purshottam L. , Sharma Harshwardhan , Srivastava Harish C. , Gharia Mahendrasinh M.
Published: November 2006

Starch from the rhizomes of Canna edulis was isolated, purified and its physico‐chemical properties are compared with maize starch. Scanning electron microscopy of the granules show that they are oval to eliptical in shape. It has low contents of lipids, ash and proteins, and has significantly higher content of amylose. It displays low water‐binding capacity and gelatinization temperature. Swelling and solubility are higher when compared with maize starch. Brabender viscosity of C. edulis starch is more than three times higher than maize starch and has shown no thinning. It retrogrades more than maize starch.
Fine Structure of Mung Bean Starch: An Improved Method of Fractionation
Authors: Oates C. G.
Published: November 2006

Laboratory isolated mung bean starch was fractionated into its amylose and amylopectin components using a modified procedure. The resulting products were shown to be both homogeneous and more susceptible to the hydrolyzing enzymes commonly used for structural analysis. The fine structure of the fractions was investigated using hydrolytic enzymes, chemical analysis and gel filtration chromatography. Differences in amylose/amylopectin fractions isolated by the modified and conventional extraction procedures were apparent. The unit chain length of amylopectin, DPn and limiting viscosity number of amylose were all lower for samples isolated by the modified method. In contrast the enzymatic hydrolysis of both the amylose and amylopectin fractions was improved for the material extracted by the modified method, low levels of branching and a unit chain distribution by gel filtration chromatography of the two overlapping populations with average degree of polymerization of 42 and 14 was obtained.
Production of Low Substituted Cassava Starch Acetates and Citrates
Authors: Agboola S. O. , Akingbala J. O. , Oguntimein G. B.
Published: November 2006

Starch acetates and citrates were prepared by treating starch with sodium hydroxide at room temperature with and without 1% concentrated sulphuric acid (per dry weight of starch) as catalyst. Starch acetates were obtained by varying the reaction time (2h, 4h, 6h and 8h) while starch citrates were obtained using citric acid monohydrate conentrations of 5, 10, 15 and 20% (per dry weight of starch). The yields of acetylated starches were greater than those of the starch citrates. Use of catalyst significantly increased the rate and extent of acetylation. Also there were progressive increases in the acetyl values of the catalysed reaction with time. Citrate substitution in catalysed and uncatalysed reactions were not significantly different at citric acid concentrations higher than 10%.
Investigation on Changes in Physical and Technological Properties of Water Soluble Sizing Agents During the Ultrafiltration Process. Part I: Ultrafiltration of Hydroxy Propyl Starch
Authors: Bayazeed A. , Trauter J.
Published: November 2006

The effect of ultrafiltration (UF) operation on the stability of a sizing agent based on starch has been studied. Hydroxypropyl starch (HPS) has been used as a water soluble modified starch. The investigation was carried out in two categories:

effect of UF time (the concentration of the solution was kept constant by recirculating the permeate), and

raising the concentration by discharging the permeate.

The changes in the HPS solution properties were assessed by investigating the rheological properties (apparent viscosity as a function of filtration time, temperature and activation energy of flow) and molecular properties (Infra‐Red spectroscopy (IR), number of average molecular weight (Mn) and molecular weight distribution). The investigation was carried out on HPS solutions before, after and during the ultra‐filtration process. The results indicated that some degradation takes place during UF process.
Glucose Production from Treated Sago Starch Granules by Raw Starch Digesting Amylase from Penicillium brunneum
Authors: Haska Nadirman , Ohta Yoshiyuki
Published: November 2006

Several microorganisms have been found to produce raw starch digesting amylase. We have isolated Penicillium brunneum from sago palm tree at a sago processing site, which was used as a source of starch digesting amylase. All the raw starch digesting enzymes were effective for cereal starches, but root starches and sago starch were resistant to the enzyme reaction.

Treatment of sago starch by heating to temperature below gelatinization temperature at lower pHs resulted in an increase in the ability of enzyme to digest sago starch granules. Heating to 60°C at pH 2.0 resulted in a conversion rate of sago starch granules to glucose near to the conversion rate of raw corn starch to glucose. At higher concentration, the degree of hydrolysis of treated sago starch granules was about 275% as compared to that of untreated sago starch granules.

Addition of the enzyme in large amount or small portion at various time intervals was found effective in the hydrolysis of treated sago starch granules.
Starch Properties of the Sweet Potato, Diploid Ipomoea trifida (H. B. K.) Don. and Tetraploid Hybrids
Authors: Shiotani I. , Nishimura A. , Yamanaka S. , Taki M. , Yamada T.
Published: November 2006

Starch properties were studied of two sweet potato cultivars (Tamayutaka and Minamiyutaka, both 2n=6x=90), two diploid (2n=2x=30) clonal strains of Ipomoea trifida (H. B. K.) Don. and their three tetraploid (2n=4x=60) hybrids (A200, A201 and A202). Starch size, iodine‐absorption spectra, amylose contents in GPC analysis, pasting properties and X‐ray powder diffraction patterns of the starches were investigated. The two I. trifida strains had smaller starch granules than those of the cultivars. The wavelength of maximum absorption and the extinction coefficients at 550, 600 and 650 nm were quite similar to each other among the cultivars and diploid strains. Amylose contents of 27% and 29% in the diploid strains were higher than those of the two cultivars. Amylose ratios of the two amylose subfractions were also compared among the starches. Starches of the diploid strains showed higher pasting temperatures and lower viscosities than the sweet potato starches. A Cb pattern of X‐ray diffraction was shown by the cultivars while the diploid strains showed a Ca pattern. Starches of the tetraploid hybrids exhibited the properties rather close to the respective sweet potato parents.
Rheological Studies on Potato Starch Pastes at Low Concentrations. Part III: Simplified Measurements of Absolute Characteristics of Pasting
Authors: Janas Piotr
Published: November 2006

Results of measurements of pasting characteristics of starch which are carried out in the rotatory viscometer with co‐axial cylinders may be expressed in absolute viscosity units. The measurements can significantly be simplified if the rotor of the construction presented in this paper is applied. The rotor may play the role of a stirrer and the measurement cylinder at the same time. The work conditions (stirring ‐ measurement) may be alternated, without any additional manipulations in the measurement system, only by a change of a angular velocity of the rotor. The rotor of the construction presented here can be also useful in rheology measurements of dispersion which sedimentates.
Comparative Efficiency of Techniques for Recovery of Ethanol from Pulpy Substrate Fermented in Solid Phase
Authors: Jaleel S. A. , Srikanta S. , Ghildyal N. P. , Lonsane B. K.
Published: November 2006

The recovery of ethanol from fermented pulp of tapioca fibrous residues by hydraulic pressing in three stages with interstage water addition lead to 79.68% relative recovery but the concentration of the ethanol in the pooled extract was nearly 60.53% of that present in the fermented pulp. The lower concentration of ethanol in extract obtained by percolation technique and poor extraction efficiency associated with other recovery processes are unacceptable from economic point of view.
Viscosity and Flow Properties of Cooked Milled Rice Slurries
Authors: Siscar‐Lee J. J. H. , Juliano B. O. , Baños Los , Tsuji S. , Chikubu S. , Faure J.
Published: November 2006

The applicability of a microcone plate viscometer for measuring some rheological properties of cooked milled rice slurries was studied on milled rices differing in cooked rice texture properties. Viscosity and flow parameters of 10 or 12.5% boiled milled rice slurries were estimated by Power Law Model with a Wells‐Brookfield RVTCP microcone plate viscometer with 2.4 cm diam. 1.565° cone at 25°C and compared with data from other methods. Cooking of the sample was critical in obtaining reproducible results. Selected pairs of samples of similar amylose contents differing in cooked‐rice texture properties by sensory and instrument methods differed also in Power Law parameters flow behavior index n and consistency coefficient m. Apparent viscosity at 10 and 20 rpm may be used to index m, but not n. Differences in m and apparent viscosity were not always those predicted by other texture indexes. Alkali spreading value at adjusted KOH concentrations may be useful in texture differentiation among rices with similar values in 1:7% KOH.
Changes of Relative Crystallinity of Potato Starch Under Gamma Irradiation
Authors: Cieśla Krystyna , Gwardys Ewa , Z̊öltowski Tadeusz
Published: November 2006

Indices of relative crystallinity of starch samples after gamma irradiation in dry form or in potatoes have been determined by differential and integral methods and compared with those calculated for corresponding reference samples. In the case of dry samples, the diminution of relative crystallinity was observed after gamma ray irradiation. In the case of starch samples extracted from irradiated potatoes, the influence of drying conditions was additionally observed. The diminution of relative crystallinity seems to be accompanied by destruction of long‐range ordering as observed by SAXS experiment.
Preparation and Characterization of Cationexchange Starches Containing Carboxyl Groups
Authors: Khalil M. I. , Farag S. , Hebeish A.
Published: November 2006

Rice starch was first crosslinked using epichlorohydrin. The crosslinked starch was then subjected independently, to graft polymerization with acrylonitrile (AN) and cyanoethylation reactions. The poly (AN)‐starch graft copolymer and the cyanoethyl starch so obtained were treated with sodium hydroxide to effect conversion of the cyanide groups of the modified starches into carboxyl groups via alkaline hydrolysis. It was found that the alkaline treatment results in decrement in the nitrogen content and increment in the carboxyl content. The magnitude of both contents is determined by sodium hydroxide concentration as well as duration and temperature of the treatment. It was also found that beside conversion of the cyanide groups to carboxyl groups, alkaline hydrolysis brings about cleavage of ether linkage of the copolymer and the cyanoethyl starch. This was evidenced by large difference observed between the sum of the substituents before and after hydrolysis. In this regard, cleavage of the ether linkage is greater with cyanoethyl starch than the poly (AN)‐starch graft copolymer. The potential value of the hydrolyzed modified starches to serve as cation exchanger was assessed through measurements of critical properties such as durability, swellability, pKa values and ion exchange capacity.
Investigation on Changes in Physical and Technological Properties of Water Soluble Sizing Agents During the Ultrafiltration Process. Part II: Ultrafiltration of Carboxy Methyl (Potato) Starch
Authors: Bayazeed A. , Trauter J.
Published: November 2006

The present work was undertaken to achieve two aims

the recoverability of carboxy methyl starch (CMS) from the diluted solutions (desizing solutions) by using the ultra‐filtration (UF) technique,

the extent of changes in the physical and mechanical properties of CMS as sizing agent after the UF recovery.

In order to investigate the effect of UF recovery on CMS properties, the diluted CMS solution was subjected to two UF cycles during the recovery, and the end product of each cycle was intensively examined. The investigations are included: the characteristic UF factors (rejection “R”, and flux of permeate “V”), viscosity, average molecular weights, molecular weight distribution (MWD), and the mechanical properties (adhesive force, weaving properties as abrasion percent AG “dust and fluff”, and clinging factor TK). The obtained results showed that:

The efficiency of the UF recovery of CMS is higher in the second than the first UF cycle.

The viscosity of CMS is:

lower after than before the first UF cycle,

higher after than before the second UF cycle.

The average molecular weight determinations are indicated the occurrence of degradation in CMS molecules.

The MWD are shifted towards unity after the UF recovery.

The changes in the mechanical properties of CMS after the UF recovery are:

Adhesion force decreased.

Abrasion % (dust and fluff) decreased.

Clinging factor TK increased.
Corn Starch (α1,4‐α1,6) Glucopolysaccharides ‐ Correlation Between Amylose: Amylopectin Ratios and Physical Properties of the Grains
Authors: Krisman Clara R. , Alfredo Curá J.
Published: November 2006

The starch components from corn inbreads and hybrids, mature seeds of commercial interest, were fractionated according to their branching degree. The amount and structural properties of them was determined, allowing a better definition of the polysaccharides present in each fraction. The methodology used allowed the visualization of the introduction of some traits if they result in a structural change of the starch components. It is, therefore, suggested that it is possible to predict the endosperm type related to hardness. A linear correspondence was obtained between amylose % and % of endosperm type floury or horny.
Reaction of Some Polysaccharides with Biogenic α‐Amino Acids
Authors: Bαczkowicz Matgorzata , Sikora Marek , Tomasik Piotr , Zawadzki Włodzimierz
Published: November 2006

Potato starch, cellulose and shells of cocoa seeds were thermolyzed with several biogenic α‐amino acids. It was found that the reaction proceeds slowly (more readily with cellulose than with potato starch) and within some hours of the reaction aromas are developed which resemble either secondary food or flower aromas. Their nature depends on all polysaccharide applied, α‐amino acid used and duration of the process. α‐Amino acids detriorate the structure of polysaccharide. In the case of potato starch 96–98% water soluble dextrins are obtained.
Solubility Behavior of Granular Corn Starches in Methyl Sulfoxide (DMSO) as Measured by High Performance Size Exclusion Chromatography
Authors: Jackson David S.
Published: November 2006

The extent of corn starch dispersibility and the relative molecular solubility of amylose and amylopectin in methyl sulfoxide (DMSO) were determined. Granular corn starches with <l, 25, 53, and 70% amylose were dispersed in 0–100% DMSO (in water) solutions at 30°C for 30 min. Maximum dispersibility for all starches (98%) was obtained when 90% DMSO/10% water was used; regular (normal) dent corn starch was equally dispersed in solutions with 88–94% DMSO. Molecular solubility, the presence of individual molecules of amylose and amylopectin, of starches was also measured (after centrifugation and filtration) by high performance size‐exclusion chromatography (HPSEC). Starches were dispersed in 90% DMSO and heated for 10 min at temperatures of 35–120ºC. At low temperatures, high coefficients of variation resulted from additional DMSO solubilization after treatment. At 120ºC, 70% amylose starch was >90% solubilized, while waxy starch was only 47% solubilized. When starches were treated for 18–89 h in 90ºC DMSO, solubility stopped increasing after 67 h. High amylose starch (70%) was mostly solubilized, but 53% amylose, waxy and regular starches could only be fully solubilized after exposure to shear. Amylopectin molecules appeared more susceptible to shear induced depolymerization than amylose. The percent amylopectin in the high amylose starches reflected that as determined by iodine binding analysis and the manufacturer; while the percent amylopectin in regular starch was too low (manufacturers: 75%, HPSEC: 65%). Undispersed components were mostly amylopectin. Since amylose is fully solubilized, however, the HPSEC can be used to quickly determine percent amylose in starch.
Carbohydrates of Red Gram dhal in Varieties Having Differences in Cooking Time
Authors: Nagaraja G. M. , Salimath P. V.
Published: November 2006

Twelve varieties of red gram with varying cooking times were studied for chemical make‐up and carbohydrate profile. Water‐soluble polysaccharides and pectic complexes were isolated from a easy‐cooking (HY‐3C) and a difficult‐cooking (GS‐1) variety of red gram and their chemical composition was studied. Content of xylose, mannose and uronic acid was more in difficult‐cooking variety. The pectic complex obtained from both the varieties was subjected to chromatography on DEAE‐cellulose. Fractionation profile and composition of the isolated fractions were different and were mainly due to xylose and mannose. Starches were isolated from these two varieties and their physicochemical characteristics showed that the solubility and swelling power of starches in water and solubility in DMSO were more in easycooking variety. Brabender viscograph studies of the flours showed linear relationship between viscosity and cooking time. Poor‐cooking varieties showed higher viscosity.
Latentiation of Chemotherapeutic Agents. Part I: Synthesis of Oxidized Starch Imine Derivatives and Antimalarials
Authors: Ferreira Elizabeth I. , Cruz Maria L. , Korolkovas Andrejus
Published: November 2006

With the purpose of obtaining animalarial prodrugs, oxidized starch derivatives with antimalarials were prepared. Imines with one drug, sulfonamide or pyrimidine, were synthesized and submitted to usual spectrometric analysis, IR. UV and 1H NMR. With these analysis it was concluded that the following compounds were obtained: derivatives of sulfamethoxazole(ML7), sulfisoxazole(ML8) sulfameter(ML11) and trimethoprim(ML13). Only sulfameter derivative was curative in 100% of mice infected with Plasmodium berghei at 50 mg/weight kg dosis.
Molecular Weight Characterization and Gelling Properties of Acid‐Modified Maize Starches
Authors: Pessa Erkki , Suortti Tapani , Autio Karin , Poutanen Kaisa
Published: November 2006

The reduction in the molecular weight distribution during acid hydrolysis of ordinary and waxy maize starch occured in two stages: first amylopectin degraded to intermediate high molecular weight polysac‐charides, secondly, these were further hydrolyzed. The amylose moiety of ordinary and high‐amylose starch was not affected very much by the hydrolysis conditions used (0.1–1 M HCI, 40°C, 0.3–4 h), but the gelling properties of starch weakened. The amylopectin degradation products, probably branched dextrins, were shown to hinder the gel formation of amylose in the starch pastes.
Poly(Acrylic Acid)‐Starch Composites. A Key for Improving Sizeability and Desizeability of Starch from Cotton Textiles
Authors: Hebeish A. , El‐Rafie M. H. , Higazy A. , Ramadan M. A.
Published: November 2006

Maize and rice starches were independently polymerized with acrylic acid (AA) using potassium permanganate/citric acid initiation system. The dependence of total conversion (grafting and homopolymerization) on AA, potassium permanganate and citric acid concentrations, time and temperature of polymerization and rate of stirring were studied. Based on the results appropriate conditions for preparation of poly(AA)‐starch composites were established. While the total conversion increased by increasing AA concentration from 10% to 30%, based on weight of starch (ows), maximum total conversion occured upon using 0,2% potassium permanganate along with 0.025% citric acid, ows, for 10 min at 40°C and stirring rate of 300 r. p. m. It was further disclosed that: (a) the total conversion for maize starch is higher than rice starch, (b) the apparent viscosity of the composite increases by increasing AA concentration from 10% to 30% and polymerization temperature from 30°C to 50°C, (c) for 10% AA concentration the composite consists of 97.67 starch and 2.33% poly‐(AA) of which 1.36% is grafted whereas for 30% AA concentration the composite consists of 79.3% starch and 20.7% poly(AA) of which 3.2% is grafted, (d) the sizeability of native starches is considerably improved after polymerization with AA and (e) size removal from cotton fabric with the composites to ca. 80% while wize removal from cotton fabric sized with native starches amounts to ca. 20%.
Structural Characteristics of Hydroxypropyl Potato Starch Granules Depending on Their Molar Substitution
Authors: Kim H. R. , Hermansson A.‐M. , Eriksson C. E.
Published: November 2006

The structural changes of potato starch granules, caused by hydroxy‐propylation, were studied using light microscopy. The starch samples used consisted of a native potato starch, hydroxypropyl potato starches with varying molar substitution (M. S.) and a hydroxypropyl and cross‐linked potato starch. The structural characteristics of the samples were evaluated by comparing the colour intensities of thin sections of samples stained with iodine and Schiff's reagent. The manner of loss of birefringence of samples in 5 M aqueous urea under polarized light was observed as well. The results obtained by three different methods were found to be similar to each other, suggesting that the central region of the potato starch granule is where hydroxy‐propylation mainly takes place or where hydroxypropyl groups are mainly distributed. The results can provide an explanation for the altered pasting properties of hydroxypropyl potato starches depending on their M. S.
A Kinetic Study of the Hydrolysis of Maltodextrin by Soluble Glucoamylase
Authors: Nagy E. , Bélafi‐Bakó K. , Szabó L.
Published: November 2006

The hydrolysis of maltodextrin with lower average degree of polymerization oligosaccharides was studied using purified glucoamylase enzyme. According to the experimental results a complex kinetic model of the reaction was developed by taking into account the concentration changes of the different reacting oligosaccharide species up to maltoheptaose. The values of the Michaelis‐Menten constants, Km,n (from Km,2 up to Km,7) were determined by the Line‐weaver‐Burk method, while the maximal reaction rate, vmax,n (vmax,2 ‐ vmax,7) was obtained by parameter estimation from the experimental concentration of oligosaccharides versus time curves obtained by maltodextrin hydrolysis.
The Modification of Starch by High Pressure. Part I: Air‐ and Oven‐dried Potato Starch
Authors: Kudta Ewa , Tomasik Piotr
Published: November 2006

Air and oven‐dried potato starch was compressed at 0.8–1.2 × 109 Pa for 60 to 600s. Structural studies have shown that observed changes are both pressure and time dependent. The amylopectin shell of starch grains is the component which suffers most essential but rather random damage. The high pressure of 1 × 109 Pa seems to cause some repolymerization of dextrin formed first under compression. The 1.2 × 109 Pa pressure causes further damage of the structure with ordering of the molecules into more crystal‐like matter. The compression of the air‐dried starch provide the formation of hard solid gels.
Identification and Quantitation of Hydroxypropylation of Starch by FTIR
Authors: Forrest Brad
Published: November 2006

FTIR spectrocopy was used to detect hydroxypropylation in modified starches. Use of derivative difference spectroscopy enabled development of a method for estimating the degree of substitution. Infra‐red spectra of a hydroxypropylated starch, and its unmodified precursor are acquired. The second derivative of the difference spectrum between the two is calculated, and the area of the peak centred at 2974cm−1 is estimated. This yields hydroxypropyl value after comparison with a calibration curve.
Alkali Extraction of Starch from Corn Flour
Authors: Mistry A. H. , Schmidt S. J. , Eckhoff S. R. , Sutherland J. W.
Published: November 2006

The alkali steeping process was tested for extraction of starch from degerminated yellow corn flour. The effect of three process parameters, alkali concentration (0.1 and 0.4%), steep temperature (25 and 55°C) and steep time (30 and 90min) were evaluated for their effect on yield, protein and sodium contents of starch. Two‐level full factorial design was used to investigate the process. The experimental results indicated that starch yield increased with increasing steep temperature and at low alkali concentration. All main effects and interactions were found to have significant effect on protein content in the extracted starch. The sodium content of the starch was effected by the three main effects and the three two‐factor interaction effects. Conditions were identified that simultaneously produced a high starch yield, low protein and sodium contents were 0.1% alkali steep at 55°C for 30 min.