bluuebunny/crossref_metadata_2025 huggingface dataset:
New Carbohydrate Derivatives from Biotechnical and Chemical Processes
Authors: Röper H. , Koch H.
Published: November 2006

Starch, its derivatives and hydrolysis products are well established as industrial products for the food and technical industries. More advanced products, based on starch, are available today, manufactured by biotechnical and chemical processes. They comprise a variety of monomeric compounds like polyols, hydroxycarboxylic acids, glycosides and their derivatives obtained by esterification, etherification and amination. In addition, interesting oligomeric and polymeric products are accessible, based on starch and its derivatives. Selected examples of these products are described as well as their respective production methods. For some products the chemicals synthesis will be compared with the fermentation route, analysing the relative advantages and disadvantages of both. The wide application potential of these “new” products is illustrated with reference to their use in different industries, e. g. in the manufacturing and processing of resins, polymers, detergents, cosmetics, pharmaceuticals and processed foods. Special emphasis will be given to the structural peculiarities of these carbohydrate derivatives, for example chirality, which enables them to act as unique intermediates in the production of biologically active products.
Synthesis of O‐Glycopeptiden
Authors: Paulsen H. , Adermann K. , Merz G. , Schultz M. , Weichert U.
Published: November 2006

Glycosyl halides of 2‐azido‐2‐deoxy‐D‐galactose derivatives can be selectively coupled to α‐glycosides with the hydroxyl groups of L‐serine and L‐threonine derivatives. Using adequate protecting groups further reactions with any amino acid are possible with the obtained carbohydrate amino acid compounds after the deprotection of the N‐ or C‐terminus. Among others examples from the field of glycophorines and interleukine‐2 are described. This method is also suitable for the synthesis of glycopeptides on solid support.
Perspektiven für zuckerhaltige Amphiphile mit Amid bindung
Authors: Pfannemüller Beate
Published: November 2006

Für die Herstellung von zuckerhaltigen Amphiphilen ist die Amidverknüpfung der präparativ einfachste Weg. Durch Reaktion der Aldonsäurelactone von Glucose und Maltose mit Alkylaminen, bzw. der N‐(2‐aminoethyl)aldonamide mit Fettsäuren im Bereich c6‐C20 wird die molekulare Struktur und die hydrophil‐hydrophobe Zusammensetzung systematisch variiert. Es wurden Produkte mit ein oder zwei nicht substituierten Amidbindungen sowie N‐methylierte Produkte hergestellt.

Aufgrund der starken Wasserstoffbindungen zwischen den Amidbrücken und den Zuckerkopfgruppen im hydrophilen Teil bilden sich in wäßriger Lösung hochgeordnete Aggregate: (a) Stabile Monolayer (C12‐C20), die für die Herstellung von technischen Membranen geeignet sind; (b) Gele aus verdünnter Lösung (C6‐C10), die nach elektronenmikroskopischen Untersuchungen aus einem lockeren Netzwerk von regelmäßig vertwisteten helicalen Strängen bestehen; (c) Lyotrop flüssig‐kristalline Phasen in konzentrierteren Lösungen, besonders ausgeprägt bei den N‐methylierten Proben (C10), oder Produkten mit einer Disaccharid Kopfgruppe und längeren Alkylkette (C16‐C18). Im letzteren Fall dominiert der Einfluß der hydrophoben Wechselwirkung zwischen den Alkylketten.

Die Versuche geben ein Beispiel, wie man die Eigenschaften von Produkten für verschiedene Anwendungsbereiche durch chemische Modifizierung nach Wunsch einstellen kann. Man erkennt ebenfalls, welch wichtige Rolle die Zuckerkopfgruppen der Glycolipide in biologischen Systemen spielen.
The Effect of Germination on Chickpea Starch
Authors: Fernandez M. L. , Berry J. W.
Published: November 2006

Chickpea and germinated chickpea starches were isolated and studied to identify changes in starch attributable to the germination process. They were characterized through physicochemical properties, digestibility in vitro, and appearance in scanning electron photomicrographs. Iodine binding capacity did not change significantly, indicating retention of the amylose/amylopectin ratio during germination. The gelatinization temperature range decreased sharply from 63–70°C to 55–63°C, however, suggesting important changes in intragranular structure. Water binding capacity increased more than 17%, and acidity increased from pH 5.9 to 5.2. Germination sharply increased the susceptibility of chickpea starch to digestibility by α‐amylase, but no change in the appearance of scanning electron micrographs could be attributed to germination.
Anmerkungen zur Qualität der Erbsenstärke
Authors: Haase N. U. , Kempf W.
Published: November 2006

Die Erschließung neuer Märkte für die Stärkeindustrie bedingt zum Teil Stärkequalitäten, die von den klassischen Stärken nicht erbracht werden. Erbsenstärke kann hier erfolgreich eingesetzt werden, wie unsere Untersuchung zeigt. Zu beachten ist aber dabei, daß sich die Stärken der beiden Unterarten sativum (Palerbse) und medullare (Markerbse) der botanischen Art Pisum sativum L. (Erbse) erheblich voneinander unterscheiden. Charakteristisch für Palerbsen ist nach unseren Untersuchungen ein Stärkegehalt von ca. 50% i.TS, während Markerbsen lediglich Werte um 30% i. TS erreichen. Bezüglich der Korngröße weisen die Palerbsenstärken einen Anteil von über 50% im Feinkornbereich auf, die Markerbsenstärken fast 100%. Die Amylosegehalte liegen bei der Palerbsenstärken mit etwa 40% bereits deutlich über den Werten der klassischen Stärken, doch werden diese Gehalte von den Markerbsenstärken mit über 70% Amylose noch erheblich überschritten.
In vitro Digestibility of Cereal and Legume (Phaseolus vulgaris) Starches by Bovine, Porcine and Human Pancreatic α‐Amylases Effect of Dietary Fiber
Authors: Socorro M. , Levy‐Benshimol A. , Tovar J.
Published: November 2006

The effect of heat treatment and dietary fiber from whole and dehulled black bean (Phaseolus vulgaris) seeds on digestibility of various starches by bovine, porcine and human pancreatic α‐amylases was studied. Corn, rice, wheat and black bean starch digestibility increased after heating. The degree of hydrolysis of black bean starch ranged between 56 and 83% of the values obtained for cereal starches depending on the enzyme used. Enzyme activity was: human‐ > porcine > bovine regardless of the substrate employed. Dietary fiber decreased starch digestibility by porcine enzyme. This effect was more marked when whole grain fiber was used. Black bean and rice starch digestibility by human amylase was not affected by fiber, while corn and wheat starch hydrolysis was slightly inhibited. The use of the human enzyme is recomended for in vitro amylolysis assays. Attention is called on the difficulties of extrapolating results obtained with animal enzymes to humans.
Transglycosidation Reactions Following Heat Treatment of Starch – Effects on Enzymic Digestibility
Authors: Siljeström M. , Björck I. , Westerlund E.
Published: November 2006

Chemical modifications in starch following heat treatment at low moisture content was studied in relation to enzymic availability of the starch. The samples, native wheat starch and a soluble starch (according to Zulkowsky), were heated with or without addition of levoglucosan (1,6‐anhydro‐β‐D‐glucopyranose), a highly reactive compound proposed to be active in transglycosidation reactions. The modifications induced by heat treatment significantly reduced the digestibility of starch in vitro. The decrease in available starch was not accompanied by any increase in dietary fibre, suggesting that the carbohydrate fragments remaining after enzymic digestion were of low molecular weight.

The starch in the heated material was highly fragmented and chemical characterization by 1H‐nuclear magnetic resonance spectroscopy and methylation analysis revealed the formation of new non‐starch linkages mainly β‐(1→4) and β‐(1→6). It is probable that the introduction of non‐starch linkages reduces the enzymic access also of several adjacing α‐glucosidic bonds. Thus, it could explain the 7% decrease in in vitro availability after 4 h heat treatment of wheat starch.
Characterization of Pullulanase and α‐Amylase Activities of a Thermus sp. AMD33
Authors: Nakamura N. , Sashihara N. , Nagayama H. , Horikoshi K.
Published: November 2006

Thermostable Thermus sp. AMD 33 pullulanases (I and II) capable of cleaving α‐1,6‐links in pullulan as well as α‐1,4‐glucosidic linkages in amylose were purified to electrophoretically homogeneous states. Relative molecular masses and pI values were determined as 135,000 (I and II) by SDS‐PAGE and 4.2 (I) and 4.3 (II) by isoelectric focusing, respectively. The pullulanase and α‐amylase activities of the purified enzyme II responded similarly to temperature and pH, with optima at 70°C and pH 5.5–6.0. Both activities were activated by Ca2+ and inhibited by Hg2+, Fe3+, NBS, DBS, SDS and urea to almost the same extent. Both activities were also inhibited competitively by CDs. Enzyme II catalyzed the hydrolysis of α‐1,6‐glucosidic linkages in maltosyl‐ and maltotriosyl‐α‐CD as well as that of α‐1,4‐bonds in amylose and related linear malto‐oligosaccarides larger than maltotriose, but exhibited no action on panose, isopanose or glucosyl α‐CD.
A Study of Native and Chemically Modified Potato Starch. Part II: Digestibility in the Rat Intestinal Tract
Authors: Björck I. , Gunnarsson A. , Østergård K.
Published: November 2006

The in vivo digestibility of the following chemically modified potato starch derivatives was evaluated in rats; distarch phosphate (DSP), acetyl di‐starch phosphate (ADSP) and hydroxypropyl di‐starch phosphate (HPDSP). Unmodified potato starch was used as reference. The starches were studied raw and after gelatinization by drum‐drying. The extent of in vivo digestion was evaluated through balance experiments in normal rats (apparent digestibility) and in rats treated with an antibiotic drug to suppress hind‐gut fermentation (true digestibility). Starch digestibility was calculated from direct measurement of starch in feed and faeces. Three different methods for starch analysis were compared.

The apparent digestibility of raw potato starches was low, ranging from 50 (HPDSP) to 84% (ADSP). The true digestibility of gelatinized unmodified potato starch was essentially complete and was not affected to any appreciable extent as a result of cross‐linking or acetylation. In contrast, etherification with hydroxypropyl significantly reduced the extent of digestion and absorption to a low level, about 50%, which was not significantly different from that with the corresponding raw material. Thus, the digestibility of the HPDSP derivative was not improved by gelatinization. The maldigested hydroxypropylated starch fraction was only metabolized to a limited degree by the hind‐gut microorganisms.
Chemical and Enzymatic Modifications of the Pasting Properties of Legume Starches
Authors: Sosulski F. , Waczkowski W. , Hoover R.
Published: November 2006

Refined legume starches were evaluated for their Brabender Visco/Amylograph properties in their native form and after chemical and enzymatic pretreatment during incubation for 20 h at room temperature. Although exhibiting the characteristic restricted paste viscosities of legume starches, native lentil starch showed much higher viscosity parameters than navy bean starch while field pea starch had very low, stable viscosities. Pretreatments with mineral acids, alkali or enzymes failed to significantly alter the amylographs of the 8% slurries (w/v). Removal of surface lipids on the refined starch granules with propanol/water (3:1 v/v) or chloroform/methanol (2:1 v/v) increased paste viscosities substantially, as did the complexation of the starches with palmitic acid or glyceryl monopalmitate. None of the treatments resulted in complete dissolution of the starch granules and the modified starches showed no improvement in gel syneresis during storage.
Swelling and Rheological Studies of Some Starch Hydrogels
Authors: Kulicke W.‐M. , Aggour Y. A. , Nottelmann H. , Elsabee M. Z.
Published: November 2006

Hydrogels with moderate water retention capacity and salt stability have been prepared from starch, oxidized starch, and amylopectin all crosslinked with epichlorohydrin. The swelling power was measured in water and in various salt solutions of different concentrations. The swelling capacity decreases with increasing both the crosslinker and the polymer concentration. The plateau modulus (G′p) of the prepared gels was determined from complex dynamic viscosity measurements. G′p was measured as a function of the epichlorohydrin and polymer concentrations. The loss modulus (G″) for the prepared gels was also measured and was always found to be almost zero. The molecular weight between two entanglement points (mesh width) was estimated from the G′p values. The ratio between the number of elastically effective entanglement points, calculated from the G′p values, and that calculated from complete conversion of the cross‐linker was also estimated for various gels. It was found that this ratio is very small (0.2–0.7%) for gels prepared with 10 wt‐% starch, it increases however to 13% at higher starch concentration of 25 wt‐%.
Some Properties of Starches of Sugary‐1; Brittle‐1 Maize (Zea mays L.)
Authors: Ninomya Y. , Okuno K. , Glover D. V. , Fuwa H.
Published: November 2006

Starch granules were prepared from mature kernels of sugary‐1 (su1) [sweet corn hybrid P39–5XP51—B] and its brittle‐1 (bt1), sugary‐1; brittle‐1 (su1; bt1), and normal counterparts. Amylose percentage and the distribution of linear chains of amylopectin were determined by gel filtration after debranching of the starches with Pseudomonas isoamylase. Pasting characteristics by differential scanning calorimetry (DSC) and starch‐granule susceptibility to amylase were also investigated. Starch granules of su1; bt1 maize are of a high‐amylose type, easily digestible, and have lower gelatinization temperature and smaller heat of gelatinization than those of the other three genotypes. Results obtained suggested that bt1 is epistatic to su1 for pasting characteristics of starch by DSC. However, su1 is epistatic to bt1 for the ratio of fraction III to fraction II of amylopectin, and amylose content and starch‐granule susceptibility to amylase are affected by both su1 and bt1 genes.
Nature of Starch Crystallinity in Parboiled Rice
Authors: Mahanta Charu Lata , Ali S. Z. , Bhattacharya K. R. , Mukherjee P. S.
Published: November 2006

A‐type X‐ray diffraction spectra of raw rice was weakened upon mild parboiling and completely disappeared in moderately severe parboiled rice. A feeble V pattern of lipid‐amylose complex appeared in its place. There was no unambiguous evidence of a B‐type spectra of retrograded starch, although partial and weak B‐like spectra could be seen. Differential scanning calorimetry showed that raw rice flour and starch had a large gelatinization and a small lipid‐amylose endotherm, the latter disappearing after defatting. The gelatinization endotherm first decreased and eventually disappeared in samples with moderately severe parboiling, but a small lipid‐amylose endotherm was visible in most parboiled rice samples. On the whole, parboiled rice appeared largely amorphous with only minor crystallinity, and the peculiar properties of parboiled rice could not be definitely ascribed to a definite crystalline form of starch.
Enzymatic Modification of Low Conversion Starch Products
Authors: Slominska L.
Published: November 2006

Recently produced low conversion starch products (maltodextrins) contain relatively low level of mono‐ and disaccharides such as glucose and maltose. A study on obtaining starch hydrolyzates containing significant amounts of glucose and maltose without fundamental change of their dextrose equivalent was conducted. The influence of glucogenic and maltogenic amylases (NOVO) on low conversion starch products was investigated by measurement of their sugar composition, viscosity, filterability, iodine absorbance value and turbidity. The results show different properties of novel starch hydrolyzates depending on the enzymes used.
Amaranth Starch ‐ Isolation and Partial Characterization
Authors: Paredes‐López O. , Schevenin M. L. , Hernández‐López D. , Cárabez‐Trejo A.
Published: November 2006

Starch was isolated from a new amaranth variety (Amaranthus hypochondriacus Mercado type) with outstanding agronomic traits. Some of its physicochemical and functional properties were comparable to a maize starch sample. After annealing, both starches exhibited little change in gelatinization peak temperature as assessed by differential scanning calorimetry. It is suggested that this behaviour might be due to the high amylopectin content of the amaranth starch and to a previous annealing effect undergone by the commercial sample during the isolation procedure. Amaranth starch granules showed by scanning electron microscopy a polygonal shape.
In vitro and in vivo Digestion of High‐Amylose Type Starch Granules
Authors: Fujita S. , Glover D. V. , Okuno K. , Fuwa H.
Published: November 2006

In vitro and in vivo digestion of high‐amylose type starch granules from sugary‐2 (su2), amylose‐extender (ae), and dull (du) maize endosperms by salivary and pancreatic α‐amylase of rats were investigated. From the results of in vitro starch granule digestion by both α‐amylases, we found a strong correlation between the starch‐granule digestibility and the wavelength at the maximum absorbance λmax, nm of the absorption spectra of starch‐iodine complexes. While the digestibility of the starch granules, which were isolated from the stomach, small intestine, and cecum of rats fed on diets containing either normal, su2, or ae starch‐granules, during passage through the mouth to the stomach of rats was calculated by using the regression equation obtained from the in vitro trials. We calculated 32–40,47–68, and 7–15% degradation of starch‐granules from normal, su2, and ae endosperms, respectively. The relative order of digestibility of starch‐granules in vivo was su2normalae, respectively, which agrees with the previous in vitro studies.
Effects of Sodium Caseinate on the Rheological Properties of Starch Pastes
Authors: Lelièvre J. , Husbands J.
Published: November 2006

Effects of sodium caseinate on the rheological properties of starch‐water pastes have been measured under steady shear conditions. In all cases a power law equation was found to describe the variation of viscosity with shear rate. The sodium caseinate increased the viscosity of the starch pastes and a starch‐sodium caseinate synergistic effect occurred. Sodium caseinate caused the swollen starch particles in pastes to increase in volume. It is suggested that this is one of the factors responsible for the observed effects of sodium caseinate on rheological behavior.
Production of Maltosyl β‐Cyclodextrin by a Bioreactor System with Pullulanase Immobilized on Partially Deacetylated Chitin
Authors: Hisamatsu M. , Yamada T.
Published: November 2006

Thermostable pullulanase (EC 3.2.1.41) from Bacillus acidopullulyticus was well immobilized on partially deacetylated chitin (PDAC‐35) with glutaraldehyde. The immobilized enzyme showed the ability of producing maltosyl β‐cyclodextrin (6‐α‐maltosylcyclomaltoheptaose) through a reverse action in a reaction mixture containing high concentration of maltose and β‐cyclodextrin, and a bioreactor system with the immobilized enzyme could produce the branched cyclodextrin more efficiently than the native enzyme. The reaction mixture was passed through a charcoal column to remove large amounts of maltose, and cyclodextrins adsorbed in the column were eluted with ethanol solutions. β‐Cyclodextrin, maltosyl β‐Cyclodextrin, and dimaltosyl β‐cyclodextrin were separated by using a ODS or a GPC column.
Starch Granule‐Bound Proteins and Polypeptides: The Influence of the waxy Mutations
Authors: Goldner W. R. , Boyer C. D.
Published: November 2006

Proteins are found as integral components of starch granule structure. The starch granule‐bound proteins from the endosperm of nonmutant (normal) and waxy (glutinous) cereals were extracted and subsequently separated by electrophoresis on denaturing SDS‐polyacrylamide gels. The silver stained gels revealed that for cereals the waxy protein (starch granule‐bound starch synthase) was approximately 60 kD. The cereals containing the waxy mutation do not show this protein. Compared to the nonmutant genotypes of other cereals, the waxy protein of barley, Hordeum vulgare is greatly diminished. Based on this observation, there may be reason to suspect that starch synthesis in barley varies from that of other cereals. There are minor homologous proteins among the cereals studied, including, maize, teosinte, rice, millet, sorghum, and barley. Starch granules from all cereal genotypes studied exhibited a minor protein at 68 kD. Most (81%) genotypes showed a 65 kD protein, which may correspond to a minor isozyme of starch granule‐bound starch synthase. Minor proteins occurred at 70 kD and 72 kD in 71% and 57% of the genotypes studied, respectively. The minor proteins could be isozymes of starch granule‐bound starch synthase or the proposed granule‐bound forms of branching enzyme and oligosaccharide synthase.
Alkali Gelatinisation of Wheat Starch
Authors: Wootton M. , Ho P.
Published: November 2006

Alkali gelatinisation of wheat starch was found to depend on starch and alkali concentration and was faster at higher temperatures and higher alkali/starch ratios. Viscosity of an alkaline starch slurry continued to increase after both in vitro digestibility and soluble amylose reached maximum values. Despite extensive granule swelling, deformation and bursting, birefringence was retained to some degree indicating differences in mechanism between alkali and heat gelatinisation.
Kombinierte enzymatische Stärkehydrolyse
Authors: Nebesny E.
Published: November 2006

Aus Untersuchungen geht hervor, daß die gemeinsam verwendeten Glucoamylase AMG 300 L® und Pullulanase Promozyme 200 L® in Mengen, die den in dem Präparat Dextrozyme 225/75 L Novo® enthaltenen Mengen angenähert sind, bereits nach 48 h die durch α‐Amylase verflüssigte Stärke verzuckern und, ähnlich wie Dextrozyme®, bis zu 98 DE ergeben. Die chromatographische Analyse zeigte, daß die die Glucoamylase unterstützende Pullulanase am wirksamsten ist, wenn sie gleichzeitig mit Glucoamylase gegeben wird. Daraus ergibt sich, daß Pullulanase die α‐1,6‐Bindungen leichter in niedermolekulare Dextrinen hydrolysiert als in den nach Einwirkung von Glucoamylase entstandenen Oligosacchariden G5 bis G7. Beim optimalen Verhältnis der Glucoamylase und Pullulanase zur verflüssigten Stärke gibt es im Medium nach 8 h Hydrolyse nicht nur keine Isozucker (Isomaltose, Panose), sondern auch keine Oligosaccharide ab G5 und Dextrine. Bei der Hydrolyse der mit α‐Amylase verflüssigten Stärke wurden mit dem Enzympräparat aus Pilzen (Fungamyl 800 L Novo®) in Mengen von 0,02–0,08%/TS, und schon nach 8 h Hydrolyse wurden 36 bis über 60% Maltose i. TS der Hydrolysate bei nur Spuren an Glucose erreicht.
Fermentation of Cassava Starch Hydrolysate with Immobilised Cells of Saccharomyces cerevisiae
Authors: Vijayagopal K. , Balagopalan C.
Published: November 2006

Fermentation of cassava starch hydrolysate with immobilised cells of Saccharomyces cerevisiae (Strain 2177) was carried out. Kieselguhr and brick powder were the substrates used for immobilisation of yeast cells. The pattern of fermentation was followed by the rate of fall in reducing sugar content and the cell growth. The results obtained showed that variations in the immobilised yeast cell preparations did not produce any effect on the rate of reduction of sugars during the fermentation. The final cell densities obtained after 48 h also did not depend on the initial immobilised cell concentration. However it was shown that fermentation could be completed in 48 h. It was also evident from the results that the cells were alive on the support used for immobilisation even after 4 cycles of fermentation.
Enhancement of Tinctorial Strength of Non‐ammonia Caramels
Authors: Sikora M. , Tomasik P. , Palasińlski M.
Published: November 2006

The enhancement of the tinctorial strength of caustic caramel was successfuly attempted by means of magnesium oxide applied in a catalytic amount. Also other catalysts were tested. Other changes occuring on the improving procedure were checked. Some enhancement of the tinctorial strength could be achieved by passing caramel through columns packed with anion exchangers.
The Effect of Substrate Diffusion Factor on Immobilized α‐Amylase
Authors: Tarhan L.
Published: November 2006

α‐Amylase of Bacillus subtilis was immobilized on acrolein‐styren copolymers of spongy and non‐spongy structures which had been modified with hexamethylenediamine followed by glutaraldehyde. Optimum bonding rates were determined from the immobilization experiments carried out with different amounts of α‐amylase, pH‐activity relationships, variation of reaction rates with the time due to the substrate diffusion limitation factor and the observed Km values were evaluated.
On the Origin of a Low Angle Spacing in Starch
Authors: Oostergetel Gerrit T. , van Bruggen Ernst F. J.
Published: November 2006

The structure of starch granules from different botanical sources was studied by transmission electron microscopy and small‐angle X‐ray diffraction. Electron micrographs of negatively stained starch granule fragments show a rippled fibrous structure. The ripples are interpreted as being stacks of thin crystalline lamellae comprising the linear α‐(1→4) chains of the amylopectin. Optical diffraction analysis of the electron micrographs showed that the spacing of the ripples varies from 9.2 nm in potato starch to 10.4 nm in barley starch. This correlates well with the position of a Bragg peak at appr. 10 nm measured by small‐angle X‐ray diffraction. These observations indicate that the Bragg peak arises from the alternating amorphous and crystalline regions seen as ripples in the electron micrographs.
Microstructure of Cotyledon Cells from Hard‐to‐Cook Common Beans
Authors: Cárabez‐Trejo A. , Paredes‐López O. , Reyes‐Moreno C.
Published: November 2006

Two bean cultivars (FM‐240 and FM‐297) were seeded in the same location, harvested and cleaned. One portion was stored for 120 days under high temperature and humidity, and another was soaked in an acetate buffer (pH 4.0–4.1. 37°C) for 5 h. Hard‐to‐cook (HTC) defect developed in both conditions as assessed by the Mattson bean cooker. Slices of bean cotyledons were prepared to study microstructural changes as a result of the HTC condition using light and scanning electron microscopy. There were some remarkable differences in some of these changes generated by both hardening procedures. Uncooked samples hardened by storage showed smooth starch granules without any apparent deformation and somewhat similar to the control, whereas by the chemical procedure these granules were clearly deformed. Cotyledon cell separation was produced when fresh samples were cooked. Cells were smaller and separation was not as evident in HTC samples from the two procedures compared to previous fresh samples. The chemical hardening technique appeared to make more rigid the cotyledon cell structure.
Raw‐starch Digestion by Chalara paradoxa Immobilized in Calcium Alginate Gels
Authors: Monma Mitsuru , Kagei Norio , Kainuma Keiji
Published: November 2006

The spores of raw starch digesting fungus Chalara paradoxa were entrapped in calcium‐alginate beads and preincubated in growth medium. The fungus devoloped a mycelium layer below and on the gel bead surface so that nutrition and oxygen in this area had direct contact with mycelia. The fungus on the bead could produce amylase and could digest raw corn starch continuously for 40 d with corn steep liquor as a nitrogen source.
Affinity Purification of Amylases on Cyclodextrin‐Sepharose Columns
Authors: Subbaramiah K. , Sharma R.
Published: November 2006

The relative affinity of α‐ and β‐cyclodextrin columns for amylases were evaluated. While both α‐ and β‐cyclodextrin columns bound α‐amylase, there was no affinity binding of β‐amylase. These columns can be used to separate α‐amylase from β‐amylase enzyme present in higher plants.
Raw Starch Digestion by α‐Amylase and Glucoamylase from Chalara paradoxa
Authors: Monma Mitsura , Yamamoto Yoshihiro , Kagei Norio , Kainuma Keiji
Published: November 2006

Glucoamylase and α‐amylase of Chalara paradoxa were separated by hydrophobic column chromatography using butyl‐Toyopearl 650M. The α‐amylase showed the highest activity at pH 5.5 and 45°C, and was stable in the pH range of 5.5–6.5 and at temperatures lower than 40°C. The glucoamylase showed the highest activity at pH 5.0 and 45°C, and was stable in the pH range of 4.0–7.5 and at temperatures lower than 45°C. The molecular mass of the α‐amylase and glucoamylase estimated by SDS polyacrylamide gel electrophoresis was 80,000 and 68,000, respectively. Both glucoamylase and α‐amylase could digest more effectively raw rice starch and raw corn starch than raw sago starch and raw potato starch. 2% raw rice starch in 10 ml solution was digested by more than 90% by 100 units of each amylase. When these amylases were used combined, raw corn starch was more effectively digested than they were used singly. This cooperative action in raw corn starch digestion was also observed when. C. paradoxa α‐amylase and R. niveus glucoamylase were combined.
Starch as Stilt Material in Carbonless Copy Paper ‐ New Developments
Authors: Nachtergaele W. , van Nuffel J.
Published: November 2006

For several reasons, calibrated wheat starch is by far the best performing stilt material in carbonless copy paper. Due to its size selection and its nice globular shape, it gives excellent stilt functionality at relatively low doses compared to native wheat starch. Less binder is needed and better copy quality obtained. It also has better runability properties than calibrated cellulose powder.

For high speed running coating machines, involving a very intensive drying, a thermo‐resistant calibrated wheat starch has been developed. This starch assures that also in the future, starch will stay the best performing stilt material for carbonless copy paper. Besides the classical advantages, such as better copy quality, the thermoresistant wheat starch offers some extra advantages, e. g. lower binder consumption.
Polymer‐Water Interaction of Maltodextrins. Part II: NMR Study of Bound Water in Liquid Maltodextrin‐Water Systems
Authors: Radosta S. , Schierbaum F. , Yuriev W. P.
Published: November 2006

The NMR relaxation times T1 and T2 for starch polysaccharides in solution were employed for the characterization of bound and free water. The “Solomon equations” were taken for the calculation of the amount of bound water in maltodextrin‐water systems. The amount of monomolecular bound water in maltodextrin solutions and gels is independent on the state in the same order of magnitude as estimated for maltodextrin powders from water vapour sorption isotherms. With increasing temperature between 1°C and 60°C a slight decrease of bound water was found.
Carbohydrate Compositions and Molecular Structure of Dextrins in Enzymatic High Conversion Starch Syrups
Authors: Nebesny E.
Published: November 2006

35% DS potato starch slurry liquefied with bacterial α‐amylase to 13,6 DE was saccharified with a combination of fungal α‐amylase and glucoamylase at different enzyme dosages ratios. Saccharification was carried out 44 h at 55°C and pH 5.0. DE‐value, carbohydrate compositions, molecular structure of dextrins and viscosity at 35°C were investigated in starch hydrolyzate samples taken after 4, 8, 20, 32 and 44 h. In dependence on the ratio of enzyme dosages of fungal α‐amylase to glucoamylase and on hydrolysis (DE) progress, changes in carbohydrate composition, decrease of molecular weight and number of dextrin branchings were observed and in dependence on them viscosity of hydrolyzate solutions decreased.
Use of the Rapid‐Visco‐Analyzer to Measure Starch Pasting Properties. Part I: Effect of Sugars
Authors: Deffenbaugh L. B. , Walker C. E.
Published: November 2006

The Rapid Visco‐Analyzer (RVA) was used to measure the effects of dextrose, sucrose, corn syrup solids and polydextrose on maize, tapioca and wheat starch pasting properties. The addition of 1 part sugar: 1 part starch tended to decrease peak viscosity, whereas peak viscosity increased at higher sugar concentrations (up to 4 parts sugar: 1 part starch). Time to onset of viscosity increase and time to peak viscosity increased as sugar concentrations increased. Dextrose, sucrose and corn syrup solids increased the maximum setback viscosity, of the starches, but polydextrose reduced setback viscosity. As the molecular weights of the sugars increased, the effects generally increased for maize and tapioca starches but not for wheat starch. Pasting property parameters measured in the RVA concurred with data obtained using other viscometers or by other techniques previously reported. The RVA is useful as an alternative tool for studying starch pasting properties and the effects of food ingredients on starch performance.
Kochextrusion von Stärke mit Hydrokolloiden
Authors: Kuhn M. , Elsner G. , Gräber S.
Published: November 2006

Bei der Kochextrusion von Maisstärke mit den Hydrokolloiden Xanthan, Gummi arabicum, Johannisbrotkernmehl und Carrageen zeigte das System aus Maisstärke mit Xanthan bei Xanthan‐Anteilen von 5–30% herausragende Eigenschaften. Bisher war zwar in der Lösung eine Interaktion von Xanthan mit Galactomannan über die β‐1,4‐verknüpften Polysaccharid‐Hauptketten beschrieben worden. Jetzt zeigte sich, daß auch unter den Bedingungen der Kochextrusion eine kooperative Verknüpfung der β‐1,4‐D‐Glucanketten des Xanthans mit den α‐1,4‐D‐Glucanketten der Stärke erfolgen kann. Hinweise darauf ergaben Messungen des Drucks und des Drehmoments während der Kochextrusion in Abhängigkeit vom Xanthangehalt. Weiterhin zeigen Kochextrudate aus Maisstärke mit Xanthan ein auffallend hohes Wasserbindevermögen und interessantes Viskositätsverhalten, so daß derartige Produkte die Funktion einer neuen Klasse von Hydrokolloiden erfüllen.
Production and Properties of Starch Phosphates Produced by the Extrusion Process
Authors: Salay Elisabete , Ciacco Cesar F.
Published: November 2006

Corn starch was phosphated on a Brabender single screw extruder at different extrusion temperatures, sodium tripolyphosphate (STP) concentration and pH of the medium. The highest degree of substitution (DS) was obtained at extrusion temperature of 200°C, STP concentration equal or superior of 1.4g/100mL of water and pH of 8.5. The DS was related to paste clarity while the extrusion process, to the water absorption index and water solubility index, independently of the DS.
Behaviour of Oxidized Starches Towards Cyanoethylation
Authors: El‐Thalouth I. Abd , Ragheb A. , Refai R. , Hebeish A.
Published: November 2006

Starch of different molecular sizes brought about by oxidation of maize and rice starches were cyanoethylated under identical conditions. The degree of cyanoethylation, expressed as % N, was found to depend mainly on the molecular size of starch irrespective of its kind. As the molecular size decreases the degree of cyanoethylation increases. Cyanoethyl starches are water soluble and can be precipitated by ethanol. It was also found that the rheological properties are determined by the nitrogen content of cyanoethyl starch. When the latter acquires low nitrogen content, it exhibits non‐Newtonianpseudoplastic behaviour. On the other hand, cyanoethyl starches with higher nitrogen content are characterized by non‐Newtonianthixotropic. At constant rate of shear, the apparent viscosity of cyanoethyl starches is directly related to its molecular size. Storing of pastes prepared from these cyanoethyl starches for 7 d exerts considerable influence on rheological properties and apparent viscosity of these derivatives.
Utilisation of Amaranthus paniculatas (Rajgeera) Starch in Salad Dressing
Authors: Singhal Rekha S. , Kulkarni Pushpa R.
Published: November 2006

Studies on utilisation of Amarantus paniculatas starch in salad dressings showed it to be more stable than corn starch. This is attributed to waxy nature of A. paniculatas starch.
Oxidized Starch as a Hardening Agent in the Gelatin‐Immobilization of Living Yeast Cells
Authors: De Alteriis Elisabetta , Parascandola Palma , Scardi Vincenzo
Published: November 2006

Periodate‐oxidized starch (oxystarch) was shown to be a good substitute for formaldehyde or glutaraldehyde as hardening agents in an immobilization procedure of microbial cells within gelatin. In fact, contrary to both aldehydes, oxystarch has no antimicrobial activity so that the immobilized cells retain their viability. Cell loading and mechanical stability of the immobilizates make them suitable for operations in continuous bioreactors.
Quinoa (Chenopodium quinoa) Starch — Physico‐chemical Properties and Functional Characteristics
Authors: Lorenz K.
Published: November 2006

Starch was isolated from quinoa (Chenopodium quinoa) for a study of physico‐chemical properties, functional characteristics and a comparison with starches from wheat, barley, wild rice, amaranth and potatoes. Quinoa starch granules range in size from 0.6 to 2.0 μm and are found within the cells of the seed as single entities or as compound structures of spherical or oblong aggregates. Quinoa starch exhibited a higher Amylograph viscosity, a greater waterbinding capacity and a greater swelling power compared to wheat‐ or barley starch. The gelatinization temperature range of quinoa starch was slightly higher than that of wheat‐ or barley starch. Amylose content was lower. As a thickening agent for fillings, quinoa starch performed better than other starches in the study. However, breads and cakes baked with quinoa starch were of poor quality. Volumes were lower, the grain non‐uniform with thick cell walls and the texture dense and compact. The overall performance of quinoa starch in baked goods was similar to that of other non‐cereal starches (amaranth‐ and potato starch).
Use of the Rapid Visco‐Analyzer to Measure Starch Pasting Properties part II: Effects of Emulsifiers and Sugar‐Emulsifier Interactions
Authors: Deffenbaugh Lynn B. , Walker C. E.
Published: November 2006

The Rapid Visco‐Analyzer (RVA) was used to study the effects of sucrose ester (SE) emulsifiers and a propylene glycol ester (PGE) emulsifier on starch cooking properties. Maize, tapioca and wheat starches were affected to different degrees by F‐160 SE with a hydrophil‐lipophil balance (HLB) of 15. Up to a concentration of 0.05 parts emulsifier to 1 part starch, the F‐160 SE increased peak viscosity, time to peak and maximum setback viscosity of the starches. These data suggested that the SE functioned by forming a clathrate complex with the starch molecules. When cooking properties of maize starch were studied in the presence of SEs with HLB 6, 11 and 15, the effects of the SE did not appear to be directly related to HLB. The PGE did not appear to form a clathrate complex with wheat starch, as indicated by a decrease in peak viscosity and time to peak. Cooking properties of the starches were also measured in the presence of sugars (dextrose, sucrose, corn syrup solids and polydextrose) at a level of 2 parts sugar to 1 part starch, plus emulsifiers at a ratio of 0.02:1. Peak viscosity, time to peak and maximum setback viscosity were affected synergistically in the presence of both sugar and emulsifier as compared to additive effects of the two ingredients acting alone. Although reaction mechanisms could not be defined from the data obtained, the RVA proved useful for quickly demonstrating the effects of multiple ingredients on starch cooking properties.
Synthesis of Poly(Methacrylic Acid‐)Starch Graft Copolymers Using Mn‐IV‐Acid System
Authors: Khalil M. I. , Mostafa Kh. M. , Hebeish A.
Published: November 2006

When starch was treated with KMnO4 solution, MnO2 was deposited overall the starch. The amount of MnO2 deposited relied on the KMnO4 concentration. Subjecting the MnO2‐containing starch to a solution consisting of monomer (methacrylic acid, MAA) and acid (citric, tartaric, oxalic or sulphuric acid) resulted in formation of poly(MAA)‐starch graft copolymer. The magnitude of grafting, expressed as meq. ‐COOH/100 g starch, was determined by amount of MnO2 deposited, MAA concentration, temperature and duration of polymerization as well as kind and concentration of the acid. Incorporation of cations such as Fe+3, Cu+2 and Li+1 had a significant effect on grafting. The highest extent and rate of grafting were obtained with citric acid and the least with sulphuric acid; tartaric acid stood in‐mid‐way position. The magnitude of grafting increased as the acid concentration increased till a certain concentration beyond which grafting levelled off. Similar trend was observed when the magnitude of grafting was related to the amount of MnO2 deposited. The extent and rate of grafting increased by raising the polymerization temperature from 30° to 50°C then decreased by raising the temperature further from 60° to 70°C. On the other hand, grafting enhanced significantly by addition of Fe+3, Cu+2 or Li+1 and followed the order Fe+3 > Cu+2 > Li+1. A tentative mechanism for grafting of starch with MAA using MnO2‐acid system was elucidated.
The Role of Starch in Biodegradable Thermoplastic Materials
Authors: Röper Harald , Koch Helmut
Published: November 2006

The increasing garbage mountain is more and more recognized as an ecological threat. Space for landfills is limited and additional incineration capacities require high capital investments and pose additional envrironmental problems. In the FRG from total annual 14 million t of household waste, 700,000 t are non‐degradable plastic materials (polyolefines, polystyrene and polyvinylchloride), especially for packaging. Different strategies are being followed to reduce the 5% plastics in household waste: prevention, recycling, chemical valorization, thermic utilization (incineration) and use of degradable polymers. The latter are reviewed in detail: chemical modification of classical polymers into photo‐ and chemo‐degradable materials, physical mixing of 6–20% granular starch with polyethylene or polypropylene, coprocessing of more than 50% disintegrated starch with hydrophilic polymers like polyacrylate or polyvinylalcohol to biodegradable films for agricultural mulch or carrying bags, thermoplastic extruded starch with plasticiser containing more than 90% starch for blister packaging and disposables for fast food and finally biodegradable polyesters like poly‐hydroxybutyric acid (PHB) and polylactic acid, produced by fermentation processes.
Preparation, Characterisation, and Rheological Behaviour of Starch‐Sodium Trimetaphosphate Hydrogels
Authors: Kulicke W.‐M. , Aggour Y. A. , Elsabee M. Z.
Published: November 2006

Ionic biopolymer hydrogels were prepared by the cross‐linking of starches with sodium trimetaphosphate in alkaline medium at 40°C for 2 hours. The swelling capacity is relatively high — up to 310 g H20/g polymer. Salt solutions have a marked influence, and result in shrinkage but not in a total collapse. The effect of both the cross‐linker and substrate concentrations on the swelling and rheological properties was investigated. The influence of temperature and NaOH concentration on the rheological behaviour suggests that they are both significant in determining the gel properties because of the readiness of the diester phosphate bonds to undergo hydrolysis. The molecular weight between two entanglement points (Me) and the effectiveness of cross‐linking [ne(r)/ne(t)] were estimated from the observed Gp′ values, and those calculated from complete conversion of the cross‐linker. The effectiveness of cross‐linking lay between 0.2 and 2.74% for 10% wlw gels, and reached a maximum of 48.1% at the higher substrate concentration of 20% wlw. 13C‐NMR signals from the anhydroglucose units became broader and decreased in intensity with rising cross‐linker concentration due to the restricted motion arising from the additional bonding.
Polymer‐Water Interaction of Maltodextrins. Part III: Non‐freezable Water in Maltodextrin Solutions and Gels
Authors: Radosta S. , Schierbaum F.
Published: November 2006

The non‐freezability of a portion of the water in maltodextrin solutions and gels was taken as a measure for polymer‐water interactions. The amount of non‐freezable water was determined by measuring the melting enthalpy of freezable water in dependence on polymer concentration by means of DSC. The amount of non‐freezable water or the water binding capacity of the maltodextrins depends on their mean molecular mass and distribution of molecular masses. The higher the P̄n the higher is the amount of non‐freezable water at high polymer concentrations. The aggregation of polysaccharide molecules does not change the amount of non‐freezable water. The gelation in connection with phase separation effects only a weak change in the mobility of free freezable water. Overriding and accidental physical and chemical variables of influence are discussed with respect to the totality of polymer‐water interactions in maltodextrins.
Conformation and Flexibility of Starch Polysaccharides in Solution
Authors: Neszmélyi A. , Holló J.
Published: November 2006

Recent results are surveyed concerning the average conformation of starch polysaccharides in solution. Special regard is given to possible detection of helical segments by high resolution NMR spectroscopy combined with theoretical energy calculations.
Supramolecular Structure of Legume Starches Revealed by X‐Ray Scattering
Authors: Gernat Ch. , Radosta S. , Damaschun G. , Schierbaum F.
Published: November 2006

The X‐ray wide‐angle scattering patterns of legume starches are attributed to the C‐type in contrast to the A‐ and B‐type of cereal and root starches. Starting from the question if this C‐pattern is to be considered as a mixed A‐ and B‐type or as an independent X‐ray wide‐angle diffractogram. examinations have been performed with starches from Vicia faba and Pisum sativum in comparison with pure A‐ and B‐type starches from maize and potato. The phase proportions in the crystalline parts of the C‐starches were calculated by means of a linear regression method. The pea starch is composed of 38.6% type B and 61.4% type A, and for the starch of bean we calculated 17.0% type B and 83.0% type A. By these results as well as by the high values for the correlation coefficients it is proved that the starch C‐polymorph is a mixture of A‐ and B‐unit cells. The legume starches consist of starch granules of pure A‐type as well as of pure B‐type in varying relations.
Carboxymethylation of Starch and Oxidized Starches
Authors: Hebeish A. , Khalil M. I. , Hashem A.
Published: November 2006

Research was designed to tailor polymeric materials for specific utilization, namely sizing of cotton textiles by making use of maize starch and rice starch. Hence both starches were subjected independently to oxidation with potassium persulphate to obtain starches with different molecular sizes. The original starches and the oxidized starches were then partially carboxymethylated with monochloroacetic acid under the catalytic influence of sodium hydroxide. In this way the molecular structure of starch, i.e., the molecular weight of the polymeric backbone and substituents present thereon, could be controlled. Results signify the following: (a) persulphate oxidation yields mixed type (acidic/reducing) of oxidized starch since the latter contains both carbonyl and carboxyl groups; (b) the extent of oxidation relies on the severity of the conditions used but it is certain that maize starch is more susceptible towards oxidation than rice starch due mainly to structural differences; (c) oxidation of starch prior to carboxymethylation enhances the amenability of starch to carboxymethylation regardless of the kind of starch used and; (d) when applied as sizing agents, carboxymethyl starches derived from oxidized starches proved to be the best and the original starches the least while oxidized starches stood in mid‐way position.