bluuebunny/crossref_metadata_2025 huggingface dataset:
Enzymic Hydrolysis and Industrial Importance of Barley β‐Glucans and Wheat Flour Pentosans
Authors: McCleary B. V. , Gibson T. S. , Allen H. , Gams T. C.
Published: November 2006

Mixed linkage β‐glucane and pentosanes (mainly arabinoxylanes) are the major endosperm cell‐wall polysaccharides of barely and wheat respectively. These polysaccharides, although minor components of the whole grain, significantly affect the industrial utilization of these cereals. The modification of barley corns during malting requires the dissolution of the β‐glucane in the cell‐wall of the starch endosperm. High β‐glucane concentration in wort and beer effect the rate of filtration and can also lead to precipitate or gel formation in the final product. In a similar manner, pentosane is thought to cause filtration problems with wheat starch hydrolysates by increasing viscosity and by producing gelatinous precipitate which blocks filters. Ironically, it is this same viscosity building and water binding capacity which is considered to render pentosanes of considerable value in dough development and bread storage (anti‐staling functions). In the current paper, some aspects of the beneficial and detrimental effects of pentosanes and β‐glucane in the industrial utilization of wheat and barley are discussed. More specifically, enzymic methods for the preparation, analysis and identification of these polysaccharides and for the removal of their functional properties, are described in detail.
Vergleichende Kernresonanzuntersuchungen der Wasserbindungsverhältnisse von Stärke und rohen Kartoffelstücken während der Trocknung
Authors: Kuhn K. , Kruschak W. , Lechert H.
Published: November 2006

Bei der Hitze‐Feucht‐Behandlung von nativer Stärke beobachtet man bei Temperaturen um 60°C eine reversible Quellung, die sich durch das Auftreten zum Teil isotrop orientierter Wasserbeweglichkeiten auszeichnet. Dabei kann das Wasser entweder nur die äußere Amylopektinschicht lockern oder aber auch in das Innere des Stärkekorns vordringen und sich in weniger fest gebundener Form mit der Amylose assoziieren.

Dieses Verhalten ist offenbar von ausschlaggebender Bedeutung bei der Warmlufttrocknung von Kartoffeln.

Neben dem Austrocknen der Randschichten des Trocknungsgutes, was eine Verringerung des Selbstdiffusionskoeffizienten in diesen Bereichen zur Folge hat und wodurch der Wasseraustritt erschwert wird, läßt sich eine weitere Einflußgröße auf die Trocknungsgeschwindigkeit beobachten, die eng mit dem oben erwähnten Verhalten der Stärke gekoppelt ist. Schon zu Beginn der Trocknung beobachtet man, daß das Wasser in der Zelle an Beweglichkeit zunimmt (Mobilisierung) und daraufhin in die Mitte der Kartoffel transportiert wird. Wenn das Trocknungsgut etwa eine Temperatur von 50–60°C erreicht hat, beginnt die Stärke zu quellen und Wasser wird dadurch immobilisiert. Zum Teil wird es auch in die bestehenden Strukturen eingeschlossen und bleibt dort relativ beweglich. Diese Vorgänge lassen sich mit der Kernresonanzspektroskopie verfolgen. Mit ihr sind Aussagen über unterschiedliche Beweglichkeiten von Wasser und dessen Mengenverhältnissen zugänglich.

Die Immobilisierung des Wassers läßt sich durch das Absinken des aw‐Wertes der Hitze‐Feucht behandelten Stärkeproben, als auch durch ihre verringerte Austrocknungsgeschwindigkeit nachweisen.
Alkaline Degradation of Monosaccharides Part VII. A Mechanistic Picture
Authors: De Bruijn J. M. , Kieboom A. P. G. , van Bekkum H.
Published: November 2006

Recent data on the alkaline degradation of monosaccharides have been used to develop a mechanistic picture of the alkaline degradation of monosaccharides. It appears that the degradation of monosaccharides themselves, particularly ketoses, is directed by the reaction conditions. So, the extent of retro‐aldolization of ketoses largely determines the amount of lactic acid formed whereas the benzilic acid rearrangement/α‐dicarbonyl cleavage/aldolization ratio of α‐dicarbonyls further influences the composition of the C1‐C6 acid part of products as well as the total amount of oligomeric products.
Herstellung und Anwendung von Zuckerkulör aus Stärkeprodukten
Authors: Smolnik H.‐D.
Published: November 2006

Zuckerkulöre sind stark dunkelbraune bis schwarze sirupartige Flüssigkeiten oder pulverförmige Produkte, die zur Färbung von Lebensmitteln verwendet werden. Sie werden nach speziellen Verfahren durch kontrollierte Hitzeeinwirkung auf handelsübliche Zuckerarten hergestellt. Zur Beschleunigung der Karamelisation können zugelassene technische Hilfsstoffe eingesetzt werden.

Aufgrund ihrer funktionellen Eigenschaften werden sie zweckmäßigerweise in 4 Klassen eingeteilt: magnified image Als Ausgangsmaterial für die Herstellung dienen vorwiegend Stärkeabbauprodukte wie Stärkezucker oder Glucosesirup. In der Bundesrepublik Deutschland belaufen sich Herstellung und Verbrauch auf etwa 10000 t/Jahr.
X‐Ray Diffraction of Starches Isolated from Yellow Corn, Sorghum, Sordan and Pearl Millet
Authors: Allah M. A. Abd , Foda V. H. , Mahmoud R. M. , Arab A. A. Abou
Published: November 2006

X‐ray analysis of starch isolated from yellow corn, sorghum (Giza 3 and 114) sordan 79 and pearl millet was carried out. The calculated “d” spacing reinforced the pattern of diffraction as “A” type. The general pattern of the X‐ray diffraction of the tested samples showed symmetric configuration with a specified diffracting angle for each sample. While no significant difference between the “d” spacing of the two types of sorghum Giza 3 and 114 was noticed, a sharp diffraction angle at “d” spacing of 5.9111 Å was observed in sordan 79.
Dehydration Artefacts in Gelatinized Starches
Authors: Bowler P. , Evers A. D. , Sargent J.
Published: November 2006

Scanning electron microscopy of swollen starch granule systems is valuable for interpretation of structural changes, but the results obtained must be interpreted with caution. The two major drying systems used, solvent exchange and lyophilization, both produce artefacts but of different types. The presence of pores on specimens prepared by lyophilization has often been interpreted as a true feature of the granule structure, but our experience suggests that this is incorrect. Furthermore, we consider that the fibrillar structure present in preparations of lyophilized starch solubles results from ice crystal formation effectively concentrating, in the remainder of the solution, solute which is subsequently preserved as a dry web.
Acceptor Molecule of Granular‐bound Starch Synthase from Sweet‐potato Roots
Authors: Baba T. , Yoshii M. , Kainuma K.
Published: November 2006

In order to elucidate acceptor molecule of starch synthase bound to starch granules, the enzyme from sweet‐potato roots was reacted with ADP‐ and UDP‐[14C]‐glucose, and the reaction products were structurally characterized. The radioactivity of the products was released as [14C]‐maltose by β‐amylase. The [14C]‐glucose incorporation was found to be mostly in amylopectin component. However, approximately 30 and 20% of total radioactivity transferred from ADP‐ and UDP‐[14C]‐glucose, respectively, were also present in a molecule with a lower molecular weight than that of amylose component. The radioactivity was incorporated into the much longer unit‐chains of amylopectin than into the usual chains. These results indicate that starch synthase bound to sweet‐potato starch granules transfers glucose from ADP‐ and UDP‐glucose into specific outer chains of amylopectin component, and that the incorporation of the glucose into a short‐chain amylose molecule is simultaneously catalyzed by the starch synthetase.
Bestimmung der funktionellen Carbamoylgruppe in Carbamatstärken und Carbamatphosphatstärken
Authors: Kessel H.
Published: November 2006

Carbamatstärken sind Ester der Carbamidsäure. Sie enthalten, gebunden an die Glucoseeinheiten der Molekülkette, Carbamoyl als funktionelle Gruppe. CONH2 ist durch Hydrolyse vom Stärkemolekül abspaltbar. Das dabei äquivalent freigesetzte Ammoniak wird mit Wasserdampf in vorgelegte Borsäure destilliert und mit 0,05‐M Schwefelsäure titrimetrisch bestimmt. Aus dem Analysenergebnis kann der durchschnittliche Substitutionsgrad und Veresterungsgrad des Derivates berechnet werden.

Die Wirksamkeit der Analysenmethode wird an zwei Urethanen, einer Carbamatstärke und einer Carbamatphosphatstärke dargelegt, die Reproduzierbarkeit durch den Wiederholstreubereich gekennzeichnet.
Studies on Purification and Kinetics of Glucose Isomerase on Hydrolysates of Starch
Authors: El‐Sahy K. M. , Siliha H. A. , Fahmy A. H.
Published: November 2006

Glucose isomerase was produced from Streptomyces phaeochromogenes by aerobic fermentation at 28°C for 24 h. The crude enzyme was obtained by disintegrating the harvested cells. Ammonium sulphate at a saturation of 0.65 gave the maximum enzyme recovery 89.4%) from the crude extract, while acetone gave 66.4% at a concentration of 3/1 (v/v). The crude enzyme extract was purified by concentration, dialysis, precipitation with ammonium sulphate, passing through a column of Amberlite, and then the eluate was treated with acetone to precipitate the enzyme. The kinetic behavior was studied and it was found that optimum D‐glucose concentration was 0.8‐M. No change in Km value was observed, while Vmax was affected.
Maltulose Formation During Saccharification of Starch
Authors: Dias F. F. , Panchal D. C.
Published: November 2006

Maltulose precursors are produced due to chemical isomerization of the reducing end glucose units during enzyme liquefaction and autoclaving of starch in the enzyme‐enzyme process of glucose manufacture. The precursors are hydrolyzed during subsequent saccharification with amyloglucosidase to form maltulose as one of the products. Temperature, pH and DE of the liquefied starch during autoclaving and α‐amylase treatment are important factors in controlling precursor formation, low temperature, low pH and low DE resulting in less maltulose formation. Acid liquefaction prior to saccharification does not result in maltulose precursor formation. Blocking of the reducing end glucose unit by hydrogenation to sorbitol prevents the formation of maltulose; maltitol is produced instead.
Change in Digestibility of Raw Starch by Gamma‐Irradiation
Authors: Kume T. , Tamura N.
Published: November 2006

Irradiation effect on digestion of raw starch by glucoamylase has been investigated as a basic research for application of radiosterilization on uncooked starch fermentation. The digestibility of raw tapioca starch decreased with an increase in dose while that of other starches such as wheat, corn, sweet potato and potato were little changed by irradiation. Tapioca starch granules coagulated by irradiation and were sedimented rapidly in suspension. The coagulation of irradiated tapioca starch granules can be dispersed completely by ultrasonic treatment. These results show that the decrease in digestion of raw tapioca starch depends on the coagulation of starch granules but other factors also contribute because the recovery of digestibility by ultrasonic treatment was not complete.
Functional Characteristics of the Mucilaginous Polysaccharides Derived from Cowpea (Vigna sinensis), Black Gram (Phaseolus mungo) and Linseed (Linum usitatissimum)
Authors: Muralikrishna G. , Bhat U. Ramadas , Tharanathan R. N.
Published: November 2006

The cowpea polysaccharides had the maximum viscosity at around pH 6 and it decreased with increase in temperature but increased with increase in concentration. Both black gram and cowpea polysaccharides stabilized against thermal disruption the foam formed by the surface active proteins. Black gram starch and the mucilage together showed greater foam stability, probably due to enhanced viscosity caused by synergistic interactions between these polysaccharides. Gelatinization temperature as well as the peak and set back viscosities of wheat starch were considerably decreased by adding either the black gram or the linseed polysaccharide. In farinograph experiments the black gram polysaccharide exhibited a strengthening effect on wheat flour dough, whereas the linseed polysaccharide resulted only in an increased water absorption. Extensographic data indicated increased resistance and decreased extensibility of wheat flour dough by the addition of black gram and linseed polysaccharides.
Properties of Starch Obtained from Frozen and Thawed Potato Tubers
Authors: Golachowski A.
Published: November 2006

Starch separated from frozen potato tubers differed from that separated from unfrozen material in the initial pasting temperature and viscosity of 7% pastes. The starch separated from frozen and thawed potato tubers was characterized by higher temperatures of pasting than starch obtained from unfrozen potato tubers. Moreover, it showed some differences in granularity, phosphorus, calcium, sodium and potassium content as well as viscosity of 7% pastes in comparison with starch obtained from unfrozen potato tubers.
Application of a Multi‐enzyme Complex in the Utilization of Potato Pulp
Authors: Slomińska L. , Starogardzka G.
Published: November 2006

Attempts of desintegration of potato pulp by use of a multi‐enzyme complex a new enzyme preparation of Novo Industri A/S have been made. The research was to help in the utilization process of potato pulp by means of dehydration and hydrolysis of containing starch. The results of experiments show the influence of the multi‐enzyme complex on the decrease of viscosity and the increase of dry substance content of the enzyme‐treated potato pulp. The action of liquefying and saccharifying enzymes on multi‐enzyme complex pretreated potato pulp yields a higher degree of liquefaction and saccharification.
Functional Properties of Okra (Hibiscus esculentus) Mucilage
Authors: Bhat U. Ramadas , Tharanathan R. N.
Published: November 2006

From immature okra pods a mucilage was isolated. The native mucilage, although not soluble in water and various salt solutions, was easily solubilized (∼ 80%) in aqueous sodium borohydride solution (1%). The viscosity of the borohydride‐soluble fraction was maximum at a pH range of 4–6, it exhibited a pseudoplastic behaviour and its viscosity decreased on adding water‐soluble additives. However, with maltodextrin an increase in viscosity was noticed, which may be the result of hydrogen bonding interactions. The fraction exhibited foam stabilizing and gelling properties, and a “strengthening effect” on soft wheat dough, as shown by farinography and extensograph experiments.
Differential Scanning Calorimetry Properties and Paper‐Strength Improvement of Cationic Wheat Starch
Authors: Craig S. A. S. , Seib P. A. , Jane Jay‐Lin
Published: November 2006

Cationic derivatives of normal corn and wheat starch were produced and investigated. Differential scanning calorimetry showed that substitution lowered the starch gelatinization temperature, the gelatinization endotherm, and the temperature of amylose‐lipid V‐complex dissociation. Substitution lowered the starch‐iodine color and inhibited precipitation of the amylose‐alcohol complex by standard fractionation techniques. Cationic derivatives of normal corn and wheat starch gave similar improvements in dry strength of paper when added at the wet‐end.
Composition of the Low Temperature Precipitate from Commercial High Dextrose Equivalent Maltodextrins and the Kinetics of its Formation
Authors: Kennedy J. F. , White C. A. , Noy R. J. , Steadb J. A.
Published: November 2006

Analysis of the precipitate formed from 50% w/w solutions of maltodextrins with high dextrose equivalents shows that oligosaccharides with degrees of polymerization of 11 and above are the major components with no evidence for the presence of small oligosaccharides with degrees of polymerization up to 7. Fast precipitating batches of commercial high dextrose equivalent maltodextrins give precipitates which contain almost constant amounts of oligosaccharides with degrees of polymerization 8 to 10, irrespective of the time of storage. For slower precipitating batches the contribution of these oligosaccharides increases with the time of storage. Analysis of the water content of the precipitate resulted in values within the range 40 to 48% w/w. This indicates that a constant gel/solvated precipitate structure exists for both fast and slow precipitating samples. Photomicroscopy of the precipitate, stained with iodine/potassium iodide, indicates that it consists of essentially spherical particles ranging from 1.0 to 8.5 μm diameter. The particle distribution is non Gaussian with approximately 90% of the particles having diameters less than 3.5 μm. The mean diameter was found to be 2.4 μm.

A study of the kinetics of the precipitation reaction showed that it cannot be considered as a single chemical reaction with zero or first order kinetics. By considering the reaction as the formation and growth of crystals in mother liquor an Avrami exponent of between 2 and 3 was obtained indicating that the reaction represents three dimensional crystal growth with instantaneous nucleation. The effect of the mean molecular weight and molecular weight distribution on the kinetics is discussed and compared to the better documented systems of bread staling and amylose retrogradation.
Thermostabile Bindung von Aromastoffen an Stärke. Teil 2: Bindung von Menthol durch Autoklavieren
Authors: Schmidt E. , Maier H. G.
Published: November 2006

Die Herstellung thermostabiler Sorbate aus Menthol und Stärken, modifizierten Stärken sowie β‐Cyclodextrin durch Autoklavieren wird beschrieben. Die gebundene Menge steigt im allgemeinen mit dem Gehalt an Amylose und beträgt maximal 80 g/kg. Mit Amylomaisstärke (49% Amylose) wurde ein 34‐Faktorenversuchsplan durchgeführt und statistisch ausgewertet. Das berechnete Maximum der Mentholsorption betrug 64,5 g/kg bei 163°C, 10 bar, 5 min und 55% Wassergehalt. Gründe für die schlechtere Bindung bei höherer Temperatur und niedrigem Wassergehalt werden diskutiert.
The Effect of Phosphoric Acid Bound with Potato Starch on Its Starch Gelatinization
Authors: Yamada T. , Morimoto Y. , Hisamatsu M. , Komiya T.
Published: November 2006

A series of potato starch substituted with proton, potassium and calcium ion were prepared with washing method by hydrogen chloride solution, and their properties were compared with that of native starch on viscograph. After viscograph test, these samples were subjected to gel chromatography and compared with that of non‐test samples. It was proved by GPC pattern analysis that with the starch substituted with proton some extent of hydrolysis took place during viscographic measurement process. The role of phosphoric acid bound with starch in this hydrolysis was discussed in relation to its content, locus and distribution in the amylopectin molecule.
Purification and Characterization of a Maltotriogenic α‐Amylase I and a Maltogenic α‐Amylase II Capable of Cleaving α‐1,6‐Bonds in Amylopectin
Authors: Suzuki Y. , Nagayama T. , Nakano H. , Oishi K.
Published: November 2006

Extracellular α‐amylases I and II, produced by a facultative thermophile Bacillus thermoamyloliquefaciens KP 1071 capable of growing at 30–66°C, were purified to homogeneity. α‐Amylase I consisted of a single polypeptide with methionine residue at the NH2‐terminus. α‐Amylase II consisted of two equivalent polypeptides each comprising a methionine at the NH2‐terminus. α‐Amylase I hydrolyzed endotypically α‐1,4‐bonds in glycogen, amylopectin and β‐limit dextrin, but not their α‐1,6‐bonds. α‐Amylase II degraded amylopectin and β‐limit dextrin in exo‐fashion by cleaving preferentially α‐maltose units from the non‐reducing ends and hydrolyzing their α‐1,6‐branch points. α‐Amylase II hydrolyzed maltotriose, phenyl‐α‐maltoside, α‐ and β‐cyclodextrins and pullulan, whereas α‐amylase I had no activity for all these sugars. α‐Amylases I and II hydrolyzed maltotetraose, maltopentaose, α‐limit dextrin and amylose, but they were inactive for maltose, isomaltose and panose. It was suggested that α‐amylase I is the most thermostable type of hitherto known maltotriogenic endo‐acting α‐amylases, and α‐amylase II is the first maltogenic exo‐acting α‐amylase able to split α‐1,6‐bonds in amylopectin.
Characterization of Starch from Bread Aged at Different Temperatures
Authors: Zeleznak K. J. , Hoseney R. C.
Published: November 2006

A series of bread samples stored at various temperatures (4°, 25°, and 40°C) were analyzed by differential scanning calorimetry (DSC) to determine if retrogradation (quantified by DSC enthalpy values) and storage temperature were correlated. The increase in enthalpy values during storage time was dependent on storage temperature. However, the rate of recrystallization was not linear at any of the temperatures studied. The net result was that the enthalpy values tended to converge with time, irrespective of storage temperature. Another effect of the increased storage temperature was an increase in the peak temperature (Tp) of the amylopectin endotherm. This indicates either that storage temperature affects the type of crystal being formed as the starch recrystallizes, or that annealing of crystals occurs at the higher storage temperatures. X‐ray diffractometry of starch isolated from the crumb gave similar diffraction patterns indicating no difference in crystal type among the treatments. In addition, the DSC endotherm became sharper at the higher temperatures. Thus, the increase in Tp was apparently the result of annealing of the crystals at the higher storage temperatures.
Effect of Hydrolysis Conditions of Cassava on the Oligosaccharide Profile and Alcohol Fermentation
Authors: Abraham T. Emilia , Krishnaswamy C. , Ramakrishna S. V.
Published: November 2006

Various hydrolysis procedures for saccharification of cassava starch were tried to maximise glucose content in the hydrolysate. The malto‐oligosaccharide profiles from HPLC analysis of hydrolysates prepared by acid, acid‐enzyme and enzyme‐enzyme showed that the hydrolysate prepared by acid contains malto‐oligosaccharides up to DP10, whereas with acid‐enzyme and enzyme‐enzyme process their presence is negligible. A commercial hydrolysate showed less amount of glucose and various sugars up to DP10. The fermentability of hydrolysates were compared and enzyme‐enzyme hydrolysate is found to be best.
Chain Length Distribution of Amylopectins of Several Single Mutants and the Normal Counterpart, and Sugary‐1 Phytoglycogen in Maize (Zea mays L.)
Authors: Inouchi N. , Glover D. V. , Fuwa H.
Published: November 2006

β‐Limit dextrins of starches of normal (nonmutant), amylose‐extender (ae), dull (du), sugary‐2 (su2) and waxy (wx) maize, and phytoglycogen of sugar‐1 (su1) maize were prepared. The β‐limit dextrins were successively debranched by isoamylase and pullulanase, and followed by quantitative gel‐filtration.

The ratio of A to B chains for the ae starch appeared to be high and that for su1 phytoglycogen was low. The ratio of short B to long B chains for the du starch was high and that for the ae starch appeared to be low. The phytoglycogen did not contain long B chains. The unit chain‐length distribution of amylopectins of the normal, wx, and su2 starches were similar. Fine structures of maize amylopectins and su1 phytoglycogen were modeled and described.
Mobility of Water in Starch‐Sucrose Systems Determined by Deuterium and Oxygen‐17 NMR
Authors: Richardson S. J. , Baianu I. C. , Steinberg M. P.
Published: November 2006

The molecular mobility of water in a starch‐sucrose system was determined by deuterium (2H) and oxygen‐17 (17O) high‐field Nuclear Magnetic Resonance (NMR) spectroscopy. The starch‐sucrose system was composed of freeze‐dried starch:sucrose (FSS) (90:10) in deuterium oxide or enriched oxygen‐17 water over the solids concentration range of 10 to 93% solids. The NMR transverse relaxation rate (R2) and peak behavior were analyzed in terms of solids concentration and water activity. R2 of the FSS system is compared to the R2 of starch and sucrose systems alone. The relaxation behavior of the 2H and 17O were compared for FSS, starch and sucrose. The results led to the conclusion that the best NMR methodology for the investigation of water mobility is provided by 17O NMR.
Eigenschaften der Triticalestärke am Beispiel polnischer Triticalesorten
Authors: Palasiński M. , Fortuna T. , Gambuś H. , Nowotna A.
Published: November 2006

Der hohe Stärkegehalt der Triticalekörner gibt Anlaß zu der Vermutung, daß dieses Getreide auch als guter Rohstoff für die Stärkegewinnung dienen kann. Daher wurden zahlreiche polnische Triticale‐Stämme und ‐Sorten auf die wichtigsten physikalisch‐chemischen Eigenschaften ihrer Stärke, wie Korngrößenverteilung, Wasserbindungsvermögen, Wasserlöslichkeit und Verkleisterungscharakteristik untersucht. Die Stärken vieler untersuchter Triticale‐Stämme und ‐Sorten verfügen über für die Stärkeindustrie interessante Eigenschaften. Im Vergleich zu Weizen scheint Triticale gut als Rohstoff für die Lebensmittelindustrie und besonders zur Stärkegewinnung geeignet zu sein. Dafür sprechen ein hoher Korn‐ und Stärkeertrag, günstige Korngrößenverteilung sowie die Viskositäten und hohen Reinheitsgrade der isolierten Stärken.
Effects of Starch Particle Size and Protein Concentration on Breadmaking Performance
Authors: Lelievre J. , Lorenz K. , Meredith P. , Baruch D. W.
Published: November 2006

Starch granules of three size classes were prepared from a New Zealand wheat by sedimentation fractionation. Each was recombined with gluten from the same wheat at protein concentrations of 8%, 12% and 16%, and test baked. The pup loaves were judged for volume, crust and crumb characteristics. Sliced crumb was physically tested in compression and shear. There appeared to be a differing optimum starch size fraction for each protein concentration; that is, there was interaction between protein and starch in forming loaf texture and volume. The most notable result is that the starch fraction greatly and directly affected the toughness or bite of the breadcrumb, but only affected the softness of chew in a complex manner dependent on the protein level. The percentage of protein had large effects on both bite and chew properties as expected.
Application of Cyclodextrins in the Chromatography
Authors: Szejtli J.
Published: November 2006

The central cavity of the cylinder‐shaped cyclodextrin molecules behaves as an empty molecular capsule: it can accomodate so called ‘guest molecules’ of appropriate size, shape and polarity. The stability of the formed inclusion complexes is however very different. This is the basis of the separation of various substances by cyclodextrins. The separation can be realized by non‐chromatographic methods or by chromatographic methods. The present review summarizes the utilization of cyclodextrins and their derivatives in gas‐liquid and gas‐solid‐, gel‐, inclusion‐, thin‐layer‐, affinity‐, and high performance liquid chromatography.
Preparation of Long‐Chain Alkyl D‐Glucosides by Alcoholysis of 1,2:5,6‐Di‐O‐Isopropylidene‐α‐D‐Glucofuranose
Authors: Straathof A. J. J. , Romein J. , van Rantwijk F. , Kieboom A. P. G. , van Bekkum H.
Published: November 2006

The acid‐catalysed conversion of 1,2:5,6‐di‐O‐isopropylidene‐α‐D‐glucofuranose (1) in 1‐butanol was studied using HPLC, 1HNMR, and 13C NMR. The course of the reaction, which involved six compounds containing isopropylidene groups, was elucidated. Eventually an anomeric mixture of butyl D‐glucosides was formed. Sulfuric, methanesulfonic, and tetrafluoroboric acid, an ion‐exchange resin (–SO3H), and a silica‐alumina catalyst showed different selectivities and catalytic activities. The ion‐exchange resin was the catalyst of choice, yielding up to 90% butyl D‐glucoside. Conversion of 1 in 1‐octanol gave a reaction mixture from which octyl α‐D‐glucopyranoside could be crystallised in 30% yield. An almost quantitative yield of the latter compound, however, was obtained by recycling the mother liquor. This procedure also avoids wasting of the ionexchange resin catalyst and the excess of octanol. 1‐Decanol and 1‐dodecanol gave crystalline α‐D‐glucopyranosides by the same method.
New Methods for Determination of Starch Gelatinisation Temperatures
Authors: Leszczyński W.
Published: November 2006

Two objective methods for determination of starch gelatinisation temperatures have been worked out. The microscopic method includes the recording of the loss of birefringence in starch granules under the conditions of progressively increasing temperatures. The conducting method enables the recording of changes in the intensity of electric current passed through gelatinising starch suspension. The temperatures are read from the curves plotted by a recorder. The new methods have proved to be fast and simple in operation. Moreover, they guarantee adequate precision of the results. The equipment necessary to carry out the tests is small in size and easy to adjust to ordinary laboratory devices.
Amylograph Pasting Behaviour of Cereal and Tuber Starches
Authors: Leelavathi K. , Indrani D. , Sidhu J. S.
Published: November 2006

The pasting characteristics in terms of peak viscosity (P), hot paste viscosity (H), cold paste viscosity (C) and at the selected fixed peak viscosities, the various ratios i.e., breakdown (H/P), setback (C/P), total setback (C/H) and relative breakdown, BDr, (P‐H)/(C‐H) to distinguish the starches from different species, are reported. Important differences in these characteristics among various starches have been observed. The amount of soluble amylose present in a starch, significantly affected its tendency for retrogradation. The breakdown (H/P), setback (C/P), total setback (C/H) ratios and especially the relative breakdown (BDr) can be made use of in distinguishing the starches from different species of wheat.
Varietal Differences in Properties Among High Amylose Rice Starches
Authors: Juliano B. O. , Villareal R. M. , Perez C. M. , Villareal C. P. , Baños Los , Takeda V. , Hizukuri S.
Published: November 2006

Among three high‐amylose starches differing in gel consistency, the hard gel starch (IR42), corresponding to harder cooked rice, had higher amylograph consistency and setback, higher gel viscosity in 0.2 N KOH and higher alkali viscograph peak than starch with soft (IR32) or medium (IR36) gel consistency. IR42 starch had less extractable starch and amylose in boiling water than IR32 and IR36 starches. The three starches had similar amyloses; the differences in gel consistency were due to the amylopectin fraction. IR42 amylopectin had higher iodine affinity, more long‐chain linear fractions on isoamylase debranching and gel filtration or 1‐butanol precipitation, and less DPn 16–17 fraction than IR32 and IR36 amylopectins.
Vergleichende Untersuchungen zur Erbsenstärkeisolierung auf naßtechnischem Wege
Authors: Haase N. U. , Kempf W. , Tegge G. , D'heur U.
Published: November 2006

Körnererbsen enthalten Stärken, die abhängig von der Sorte über sehr hohe Amyloseanteile verfügen. Für die bisher weitgehend fehlenden analytischen Untersuchungen derartiger Stärken müssen vorab möglichst gute Isolierungen durchgeführt werden. Deshalb wurden in der vorliegenden Untersuchung die drei Verfahren der Flutung, der Zentrifugation und der Extraktion einander gegenübergestellt, wobei die Proteinabtrennung besonderes Gewicht einnahm. Ein kurzzeitiger Kontakt der vermahlenen Erbsen mit Natronlauge führte sowohl bei der Flutung als auch bei der Zentrifugation zu einer vergleichbar hohen Stärkequalität, doch lag der Wirkungsgrad der Stärkeabtrennung bei der Flutung um 30% höher. Die Extraktion fiel gegenüber den beiden anderen Methoden bezüglich der verwendeten Meßkriterien deutlich ab. Ein zusätzlich vorgenommener Sortenvergleich wies darauf hin, daß die Stärke aus Palerbsen besser abtrennbar ist als die aus Markerbsen.
Catalytic Properties of Bacillus megaterium Amylase
Authors: David M.‐H. , Günther H. , Röper H.
Published: November 2006

A new amylolytic enzyme from Bacillus megaterium is described, which is produced as a trace contaminant in a complex protein mixture, with β‐amylase as the major enzyme. By genetic engineering, the productivity could be increased by a factor 10000, and the enzyme is free of other amylases. Compared to pullulanase, which catalyses pullulan degradation to maltotriose, B. megaterium amylase (BMA) does not attack 1,6‐linkages and hydrolyses pullulan exclusively to panose. Furthermore, it hydrolyses crosslinked Phadebas starch, used for determination of α‐amylases and it also catalyses transfer reactions. Those are strongly enhanced in presence of suitable acceptors, which can be sugar molecules with the same configuration as dextrose in C2, C3, C4‐position. In the industrial dextrose process, about 1% of oligosaccharides remains from starch which is difficult to be hydrolysed, thus reducing yield and quality of the final product. The structure elucidation showed 35% 1,6‐linkages being present. These oligosaccharides can be degraded and eliminated by BMA through panosyl transfer to dextrose, under formation of 63‐α‐glucosylmaltotriose, which is degraded by glucoamylase to dextrose.
Properties of Starches Isolated from Western Samoan Breadfruit Using a Traditional Method
Authors: Tumaalii F. , Wootton M.
Published: November 2006

Starches were isolated from the pulp of seven varieties of mature Western Samoan breadfruit using a traditional method. Proximate analysis, starch damage and amylose contents were measured. Isolated starches were further examined by image analyser to determine particle size distribution and by X‐ray diffraction. Gelatinisation was studied by Visco‐Amylograph, and by swelling power and solubilisation during heating in water. The starches were as low in non‐starch materials except protein (0.37‐ 1.08%) as commercial starches from most other sources. Breadfruit starch showed the B‐type X‐ray diffraction pattern common in tuberous starches and resembled potato starch in its gelatinisation behaviour. Variations in particle size, gelatinisation behaviour, starch damage and amylose level existed between starches from the different varieties and would influence selection as a starch for specific purposes.
Auswirkungen einer Feuchtkonservierung von Mais auf die Stärkequalität
Authors: Haase N. U. , Kempf W.
Published: November 2006

Die Maisstärkegewinnung aus einheimischem Körnermais ist mit Einschränkungen möglich. Aufgrund von Feuchtegehalten der Körner zwischen 30 und 40% bei der Ernte wurde statt einer Trocknung eine Feuchtkonservierung erprobt. Bei den Versuchen mit Natriumhydrogensulfit traten hinsichtlich der qualitativen Aspekte der isolierten Stärken über die Versuchsdauer von 24 Wochen keine wesentlichen Unterschiede zu nicht gelagerten Referenzstärken auf. Die Silierung von Maiskorn‐Spindel‐Gemischen in Form einer Milchsäuregärung führte ebenfalls zu Stärken einer gleichmäßig guten Qualität. Somit sind beide Formen der Feuchtkonservierung als vorgeschaltete Lagerungsverfahren der Maisstärkegewinnung geeignet.
Absolute Measurements of the Rheological Properties of Gelatinized Starches.
Authors: Windhab E. , Tegge G. , Tiemeier U.
Published: November 2006

Die Beschreibung des rheologischen Verhaltens von Stärkepasten wird im allgemeinen auf der Grundlage von Messungen vorgenommen, welche nur die empirische Beurteilung zulassen. Der Grund dafür ist die Verwendung von Meßgeräten, die keine rheometrische Strömung realisieren. Unter Verwendung von Absolutrheometern (Rotations‐und Kapillarrheometer) ist es möglich, bei Berücksichtigung der rheologischen Parameter, Zeitverhalten (Thixotropie) und Wandgleitverhalten, reproduzierbare geräteunabhängige Fließfunktionen zu bestimmen. Die Fließgrenze verkleisterter Stärkepasten als wichtiger charakteristischer Parameter zur Kennzeichnung der “dickenden” Wirkung wurde mittels einer neu entwickelten Meßeinrichtung gemessen. Auf der Grundlage dieser Meßtechnik erfolgte die Quantifizierung des Einflusses der Parameter: Kochzeit, Stärkekonzentration, Stärkeart, Temperatur und Alter der Stärkepaste auf die rheologischen Kenngrößen der Stärkepasten.
Benefits of Bacillus megaterium Amylase in Dextrose Production
Authors: Hebeda R. E. , Styrlund C. R. , Teague W. M.
Published: November 2006

A Bacillus meguterium amylase (BMA) has the ability to convert branched saccharides to a form that is easily hydrolyzed by glucoamylase. Concequently, dextrose production can be improved by using a combination of BMA and glucoamylase in saccharification. Benefits provided by BMA are similar to those achieved with a debranching enzyme. For instance, BMA is effective in increasing dextrose yield, while at the same time, nearly eliminating tetra‐ and higher saccharides. BMA can also be used to increase saccharification rate, reduce glucoamylase dosage, or maintain normal dextrose level at higher solids. Benefits of BMA have been quantified by evaluating the enzyme in combination with glucoamylase using typical industrial saccharification conditions.
Graft Copolymerization of Acrylonitrile on to Guar Gum by Hydrogen Peroxide Initiation
Authors: Raval D. K. , Patel R. G. , Patel V. S.
Published: November 2006

Grafting of acrylonitrile on to guar gum by hydrogen peroxide initiation in aqueous media was achieved at different reaction conditions. Effects of hydrogen peroxide concentration and the amount of guar gum on grafting parameters have been discussed. Increasing H2O2 concentration (i. e. from 5 mmol to 20 mmol) increased the conversion of monomer and % add‐on, whereas the average molecular weight of grafts and the grafting frequency decreased. An increase in the amount of guar gum also increased the conversion of monomer and grafting frequency but decreased the % add‐on and increased the average molecular weight of the grafts. The graft copolymer is also characterized by infrared spectrophotometry.
Coupling Reaction of Bacillus macerans Cyclodextrin Glucanotransferase on Glucosyl‐α‐cyclodextrin and Glucose
Authors: Kobayashi S. , Ashraf H.‐R. Lee , Braun P. , French D.
Published: November 2006

Treatment of glucosyl‐α‐cyclodextrin with radioactive glucose in the presence of Bacillus macerans cyclodextrin glucanotransferase, yielded radioactive maltose, maltotriose, and four kinds of glucosyl branched oligosaccharides. The branched oligosaccharides formed had identical Rf values as those of branched oligosaccharides of 5‐8 glucose unit on paper chromatography using the solvent system of 1‐butanol: pyridine: water (6/4/4), (Fractions B5‐B8). Individual oligosaccharides were isolated and their structures determined using the action of porcine pancreatic α‐amylase, β‐amylase, pullulanase, isopullulanase and glucoamylase. The structure of the main component of the fraction B5 was 64‐O‐α‐glucosylmaltotetraose, B6 was 64‐O‐α‐glucosylmatopentaose, B7 was 65‐O‐α‐glucosylmaltohexaose, and B8 was 66‐O‐α‐glucosylmaltoheptaose. Fraction B8, which formed at the initial stage of the reaction, contained 64, 65 and 66‐O‐α‐glucosylmaltoheptaose. Reducing end 14C‐labelled 64‐O‐α‐glucosylmaltotetraose was degraded to 63‐O‐α‐glucosylmaltotriose and radioactive glucose by the exhaustive action of Bacillus macerans cycloamylose glucanotransferase, and 63‐O‐α‐glucosylmaltotriose was completely non‐reactive to the enzyme. From these results, we proposed a model of the active site of the enzyme.
Beseitigung von Weizenstärkeindustrie‐Abwässern – Ein Wirtschaftlichkeitsvergleich
Authors: Witt W. , Kröner H.
Published: November 2006

Die Produktion von Weizenstärke spielte an der Gesamtstärkeproduktion aus Mais, Kartoffeln und Weizen in der Vergangenheit eine untergeordnete Rolle. Neue Verfahrenstechniken zur Gewinnung von Weizenstärke sowie entsprechende EG‐Marktregelungen lassen die Produktion von Stärke aus Weizen bzw. Weizenmehl in jüngster Zeit interessanter erscheinen. Aufgrund der größeren Verarbeitungsleistung in Weizenstärkefabriken sind daher alternative Abwasser‐Behandlungsmethoden zu der Verregnung gefragt. Hier sind zu nennen die vollbiologische Reinigung in einer Belebungsanlage, die Eindampfung, Filtration, Eiweißkoagulation, Vermarktung als Viehfutter, Fermentation und die anaerobe Reinigung. Welche dieser Abwasserbehandlungsmethoden sich großtechnisch durchsetzen, hängt nicht nur von der Verfahrenstechnik und der Reinigungsleistung, sondern auch wesentlich von der Wirtschaftlichkeit ab. Hier rückt in letzter Zeit die anaerobe Reinigung organisch hochbelasteter Abwässer immer mehr in den Vordergrund. Ein Vergleich der verschiedenen Behandlungsmethoden zeigt, daß die Kosten sehr stark vom Abwasserfaktor, d. h. der Abwassermenge pro Tonne verarbeitetes Mehl, und den Strom‐ bzw. Energiekosten abhängig sind. Bei der Berechnung der Kosten müssen Kosten für eine evtl. Nachklärung in einer kommunalen Kläranlage und Erlöse für Biogas oder Konzentrat berücksichtigt werden.
Change in Digestibility of Gamma‐Irradiated Starch by Low Temperature Cooking
Authors: Kume T. , Rahman Saifur , Ishigaki I.
Published: November 2006

Combination effect of irradiation and low temperature cooking on starch digestibility has been investigated as a basic research for application of radiosterilization on starch fermentation. The digestion of corn starch by glucoamylase after cooking at low temperature was enhanced by γ‐irradiation and the required cooking temperature was decreased from 75‐80°C to 65°C by 25 kGy. Gelatinization of starches except tapioca starch was enhanced by irradiation and it corresponds to the digestibility. The digestibility of potato starch which has a high viscosity was especially enhanced at low temperature cooking because the viscosity was markedly decreased by irradiation. These results show that the irradiation of starches is useful not only for the sterilization of fermentation broth but also for the enhancement of digestion.
Structure and Properties of Water Chestnut (Trapa natans L. var. bispinosa Makino) Starch
Authors: Hizukuri S. , Takeda Y. , Shitaozono T. , Abe J. , Ohtakara A. , Takeda C. , Suzuki A.
Published: November 2006

The Brabender amylogram (6% concentration) of water chestnut (Trapa natans L. var. bispinosa Makino) starch showed that its pasting temperature was 71°C and its viscosity was low (max, 310 B. U.) which remained constant during heating and increased slightly on cooling. The starch showed a Cc or Ca type X‐ray diffraction pattern, and the susceptibility of the granules to amylases was intermediate between those of corn and potato starches. The number‐ and weight‐average degrees of polymerization (D.P.) of the amylose were 800 and 4210, respectively. The apparent d. p. distribution was 160–8090. The amylose was composed of 3 components differing in molecular size and the number of chains, and 89%, by number, of the molecules were linear. The amylopectin contained 44 ppm of phosphorus, and its number‐ and weight‐average chain lengths were 22 and 26, respectively.
Gel Chromatography of Residue and Extract Obtained from Starch Granules by Hot Aqueous 1 ‐Butanol Solution Treatment
Authors: Taki M. , Suzuki K. , Taki A. , Hisamatsu M. , Yamada Tetsuy A.
Published: November 2006

Starch granules of corn starches (normal, waxy, amylo and amylowaxy) and potato starch were treated with hot aqueous solution saturated with 1‐butanol and fractionated. These fractionated starches were subjected to an advanced gel chromatography with a column system of Toyopearl HW 75 F. Amylose of normal maize and potato starches was perfectly leached out from the granules, but that of amylo maize was not perfectly extracted. Amylo and amylowaxy maize starches were proved to have large amount of low‐molecular weight material. Normal and amylo maizes, and potato starches contained a high‐molecular‐weight material recognized as amylose type, and it is strongly suggested that amylopectin of normal maize is not same as that of waxy maize. It was found that the GPC analysis was a very important step to estimate an amylose content since a part of amylopectin made a precipitable complex with 1‐butanol.
Effect of the Hard‐to‐Cook Phenomenon on Some Physicochemical Properties of Bean Starch
Authors: Paredes‐López O. , Maza‐Calviño E. C. , Montes‐Rivera R.
Published: November 2006

Two bean varieties of outstanding agronomic performance were seeded, harvested and a portion stored for 135 days under high temperature and humidity. These varieties were Negro Qro and Canario with black and light yellow seeds, respectively. Hard‐to‐cook (HTC) defect developed in aged seeds as assessed by the Mattson cooker and Instron texturemeter. Fresh and HTC beans were used in order to determine physicochemical changes in starch and to evaluate its contribution in textural defects. The damaged starch content, water absorption and swelling were higher for isolated starches from HTC seeds than for the controls. Starch damage was generated by enzymatic attack and/or by mechanical action during milling. Pasting properties examined with the Brabender viscograph showed that peak viscosity increased and stability and retrogradation capacities declined after storage. These results might be ascribed to the starch damage and also to changes undergone by the residual impurities of isolated starches. In agreement with the previous observations, scanning electron microscopy of starch isolated from HTC samples revealed the presence of some swollen granules and many others with fissures, while those from controls had smooth surfaces and with no evidence of damage. Differential scanning calorimetry (DSC) evaluations showed that gelatinization temperatures and transition enthalpies were not significantly influenced by storage; results in agreement with birefringence studies. It is suggested that the changes in the starch from defective seeds were not sufficient to modify the gelatinization performance.
Rheological Properties of Leucaena glauca Gum in Aqueous Solutions
Authors: Raval D. K. , Patel R. G. , Patel V. S.
Published: November 2006

The flow properties of Leucaena glauca gum solutions were studied in the range of shear rates 1.5 to 1310 s−1, using a rotational viscometer Rheotest 2. The flow behaviour of aqueous solutions of the polysaccharide is pseudoplastic, and transition from Newtonian to pseudoplastic behaviour occurs in the low shear rate range at concentrations of interest to the industry. The flow of polysaccharide solutions is described by equation of state proposed by M. M. Cross. The basic rheological parameters, like zero shear rate viscosity (ηo), infinite shear rate viscosity (ηα) and a constant associated with the rupture of linkages (α) were calculated applying simple and established relations. The effect of concentration and temperature on rheological parameters have been studied. The Cross equation is found to be applicable to the data with a good degree of accuracy over a wide range of shear rates.
Synthesis and Properties of Polyacrylamide‐Starch Graft Copolymers
Authors: Hebeish A. , Bayazeed A. , El‐Alfy E. , Khalil M. I.
Published: November 2006

Graft polymerization of acrylamide onto rice starch was investigated under different conditions using potassium persulphate, benzoyl peroxide or potassium permanganate as initiator. This has led to establishment of the most appropriate grafting conditions for each of these initiators. Under these conditions grafting was characterized by two rates regardless of the initiator used. The first rate occurred during the initial stages of polymerization while the second during the later stages. The first rates of grafting for the three initiators were very close indicating the insignificant effect of the nature of the initiator on grafting during the initial stages of the reaction. On the other hand, the second rates of grafting exhibited the order: potassium persulphate < benzoyl peroxide < potassium permanganate, reflecting the role played by the nature of initiator during the later stages of the reaction. Substantial differences in solubility were observed between polyacrylamide‐starch graft copolymers and unmodified starch as well as among copolymers prepared using the three initiators. Although the copolymers acquired higher solubility percent than the unmodified starch, yet nature of initiator, graft yield, structural changes in the copolymer occuring during grafting and the temperature of solubility measurement determined the solubility percent. Copolymers prepared using benzoyl peroxide or potassium persulphate showed lower viscosity than the unmodified starch. The opposite was the case with respect to copolymer prepared using potassium permanganate.