bluuebunny/crossref_metadata_2025 huggingface dataset:
Buffalo Gourd Root Starch. Part III. Effects of Plant Age and Spacing upon the Physico‐chemical and Rheological Properties
Authors: Scheerens J. C. , Dreher M. L. , Bemis W. P. , Berry J. W.
Published: November 2006

Buffalo gourd (Cucurbita foetidissima HBK) starch was previously shown to have potential for incorporation in food products. As annual cropping systems have been suggested to produce the highest starch yield per unit of land and time, a study of the effects of plant age and spacing upon the physico‐chemical and rheological properties was undertaken. Root starch content reached a plateau level (18% of fresh weight) near 2.5 months of growth in 1979, but continued to increase up to 4.5 months of age in 1981. Substantial changes among samples of different age and spacing for other compositional parameters were not observed. However, vine senescense was associated with a decrease in starch level and a concomitant rise in free sugar content. Proximate analysis of starches revealed little variation among samples. Mean granule diameters appeared to increase with increasing plant age. Patterns among samples associated with water binding capacity, alkali number, iodine affinity, inherent viscosity, or gelatinization temperature were not recognized. Internal organization of components within the granule appeared to decrease with increased plant age as shown by the parameters of swelling power, percent solubility, initial pasting temperature, and initial viscosity at 95 °C. All samples formed well developed pastes, which increased viscosity upon cooling, with final gel strength being independent of plant age or spacing.
On the Acid Resistance of Starch Granules
Authors: Nara S. , Sakakura M. , Komiya T.
Published: November 2006

When potato starch was hydrolyzed to form Nägeli amylodextrin by 16% sulfuric acid at 30°C, only the amorphous portion of the starch granules was deteriorated. The crystallinity of Nägeli amylodextrin showing the hydrolysis ratio of 0.22 was 1.28 times as large as that of original starch. The hydrolysis process at above 45°C was given by two exponential equations. The value of acid resistance portion (Co) at 30 and 38°C was 100%, while the values at 45, 50 and 55°C were 67, 38 and 18%, respectively. The high value of Co generally showed the high acid resistance in the various starches. Sweet potato and waxy rice starches were more easily hydrolyzed than other starches, although they gave the relatively high value of Co. Thus, it was slightly more difficult for low acid resistance portion of potato starch to be hydrolyzed than for that of other starches. Moreover, that of waxy rice was easily hydrolyzed.
Herstellung von Phenolharzen unter Verwendung von Stärkeprodukten
Authors: Koch H. , Krause F. , Steffan R. , Woelk H. U.
Published: November 2006

Bei der Herstellung von Phenolharzen vom Novolak‐ und Resol‐Typ wurde die Mitverwendung von Stärken und Stärkehydrolysaten untersucht; die Kohlenhydrate wurden hierbei in situ durch saure Katalyse zu 5‐Hydroxymethylfurfural (HMF) dehydratisiert, das in Gegenwart von Phenol und Formaldehyd in die Harze eingebaut wird. Im Vergleich zu kommerziellen Phenolharzen sind Einsparungen von bis zu 40% Phenol und 65% Formaldehyd möglich. Bei sehr geringen Restmonomergehalten härten die modifizierten Harze mit zunehmendem Kohlenhydrateinbau rascher aus, wodurch eine Beschleunigung technischer Verarbeitungsprozesse möglich erscheint.

Insbesondere Stärkehydrolysate mit unterschiedlichen mittleren Molekulargewichten können gezielt eingesetzt werden, wenn spezielle Eigenschaftsprofile der Harze, wie z. B. Erweichungspunkte, Molekulargewichtsverteilungen, Viskositäten und Vernetzungsverhalten, eingestellt werden sollen.
Starch Microspheres. Microcalorimetric Determination of Kinetics and Heats of Enzymatic Degradation
Authors: Lindberg B. , Engdahl K.‐Å. , Ahlberg P.
Published: November 2006

The enzymatic degradation of crosslinked starch microspheres has been investigated by means of batch microcalorimetry. The thermokinetic parameters and heats of reaction have proved useful for the characterization of the enzymatic degradation properties of starch particles.
Intensification of Amylase Synthesis with Aspergillus niger by Way of Multistage Mutagenization
Authors: Ilczuk Z. , Fiedurek J. , Paszczynski A.
Published: November 2006

Conidia of amylolytically active Aspergillus niger C strain were subjected to four‐stage mutagenization, using different combinations of mutagens in each stage (stage I – UV irradiation + ethyleneimine, stage II – UV irradiation + nitrosomethylurea, stage III – UV irradiation + N‐methyl‐N′‐nitro‐N‐nitrosoguanidine, stage IV – acryflavine). In all, 378 strains were isolated after mutagenization, which were initially evaluated for the total amylolytic activity by the method of test‐tube microculture. Nine most active mutants were then tested in submerged culture determining the activity of glucoamylase and α‐amylase in post‐culture liquid. The activity of α‐amylase increased from over 7 to nearly 31%, and that of glucoamylase from 4 to over 61%.
Studies on the Relationship Between Water‐satured State and Crystallinity by the Diffraction Method for Moistened Potato Starch
Authors: Nara S. , Komiya T.
Published: November 2006

Crystallinity was measured by X‐ray diffraction method and water‐saturated state was determined by means of the moisture contents calculated from the crystallinity for moistened cellulose and potato starch. In the X‐ray diffractograms the upper areas which were separated by the straight line joined the points of intensity at 37° and 4° (8°) of diffraction angle was the relative reflection area in the crystalline and amorphous portions, and the lower area was the background of the non‐relative reflection area. The upper area separated by the smooth curve joined the minimum intensity at 4° to 37° of diffraction angle corresponded to the crystalline portion and the lower area to the amorphous one. The ratio of the crystalline portion to sum of the crystalline and amorphous portions was considered to be crystallinity. Crystallinity of the air‐dried and the moisture‐saturated (28%) samples of cellulose were 0.68 and 0.71, resp. The crystallinity of the air‐dried and water‐saturated (49%) samples of potato starch were 0.24 and 0.32, resp.
Developmental Changes in Starch Properties of Several Endosperm Mutants of Maize
Authors: Inouchi N. , Glover D. V. , Sugimoto Y. , Fuwa H.
Published: November 2006

The properties of starches during development of several endosperm mutants of maize were investigated. Starch contents of normal and waxy (wx) kernels were higher than those of dull (du), sugary‐2 (su2), and amylose‐extender (ae) kernels, and in general the greater increase in starch contents occurred earlier in kernel development. The normal, du, su2, and ae mutants in that order, respectively, increased the apparent amylose concentration of the starches as measured by the “blue value” method. Within each of these genotypes, absorption intensity increased and λ max. of absorption curves shifted to a longer wavelength region with increasing maturity. Waxy starches did not change in either of these properties at any of the developmental stages. Few detectable differences were observed in X‐ray diffraction intensity, gelatinization temperature, heat of gelatinization, and the photopastegrams within these genotypes during development. Exhaustive degradation of starch granules by glucoamylase showed that ae starches were more resistant to amylase than the other starches. Except for wx, the starches tended to be more resistant to amylase with increasing maturity.
Effects of Organic Molecules on the Gelatinization Temperature of Starch
Authors: Oosten B. J.
Published: November 2006

The effects of organic molecules on the gelatinization temperature of starch in water seem to stem from the electron polarizability of those organic molecules. The same fundamental characteristic is the basis of the explanation for the effects of anions on the gelatinization temperature. The proposed hypothesis is capable to explain the familiar phenomena which arise from the interactions between starch and electrolytes.
Determination of Functional Groups in Glucose Isomerase
Authors: Hoschke Á , Balogh K. , László E. , Holló J.
Published: November 2006

Following the introduction and widespread application of immobilized glucose isomerase for the industrial production of isosyrup (HFCS), the most significant challenge facing experts is to solve the problem of increasing the fructose content. In addition to well‐known procedures another approach may be the changing of the equilibrium of the enzymatic reaction by modifying the active centre of the enzyme. Histidyl‐, ϵ‐amino‐, arginyl‐, tyrosyl‐ and tryptophyl‐ amino acid side chains in the active centre have been modified by means of selective protein reagents. The results were evaluated by kinetic methods and the role of functional groups of amino side chains has been determined. A new hypothesis is proposed for the mechanism of enzymatic reactions.
A High Yield of Amylase from Aspergillus niger by the Effect of Gamma Irradiation
Authors: El‐Saadany R. M. A. , Salem F. A. , El‐Manawaty H. K.
Published: November 2006

When irradiated rice starch was used as a media for Aspergillus niger a noticeable increase of amylase production was observed. Molecular degradation of starch molecules did occure, and an increase in starch acidity and solubility was noticed, whereas a marked decrease in viscosity as well as swelling capacity was observed. Gelatinization time and temperature of irradiated starch became shorter or lower resp. These results showed that internal changes in irradiated starch molecules and an alteration in its molecular configuration occured. They may affect the pathway of the growth of the fungi Aspergillus niger. When the amount of amylase was determined by measuring enzyme activity, it was observed that amylases in the irradiated media were higher than in the control media.
Einsatz der Hochdruckhomogenisierung zur Auflösung der Zellstruktur von Stärkekartoffeln
Authors: Meuser F. , Wittig J. , Huster H.
Published: November 2006

Zusammenfassend kann über das neue Hochdruckaufschluß‐Verfahren festgestellt werden, daß es gegenüber der Zerkleinerung mit Reiben eine spezifischere Auflösung der Zellstruktur der Kartoffeln bewirkt, den Anteil an gebundener Stärke in der Pülpe weiter absenkt und den Lufteinschlag in das Reibsel weitgehend verhindert. Daraus resultiert eine höhere Stärkeausbeute und die Möglichkeit, helleres Protein mit einem erheblich herabsetzbaren SO2,‐Verbrauch gewinnen zu können. Daneben bietet das Verfahren weitere Vorteile, die darin bestehen, daß der Prozeßablauf vollautomatisch gesteuert und das Schichtpersonal für die Reibenbelegung eingespart werden kann. Das gesamte System kann einem “Clean in Place” ausgesetzt werden.
Zucker aus Stärke ‐Rückschau und Ausblick
Authors: Tegge G.
Published: November 2006

Die Entwicklung der Stärkeverzuckerung, ihr rasches Fortschreiten durch politische Ereignisse und die Parallelen der Entwicklung der Rübenzuckerindustrie zu Beginn des 19. Jahrhunderts werden beschrieben. Die Stärkezuckerfabrikation bis zum Beginn ihrer Ausübung in industriellen Maßstäben wurde bald im breiteren Rahmen durchgeführt und in die Hände erfahrener Chemiker übergeleitet. Die damit verbundene Industrialisierung zeigte eine Reihe bemerkenswerter Grundlagenkenntnisse. In den 40iger Jahren des vorigen Jahrhunderts tauchten die Druckkonvertierung und die indirekte Beheizung auf. Auch waren zahlreiche Filtrationsverfahren entwickelt worden. Weitere Verbesserungen zeigten sich in der Verdampfer‐ und Entfärbungsarbeit mit Knochenkohle. Die wirtschafliche Entwicklung in Deutschland, in den USA und in der EG wird aufgezeigt und mit Neuentwicklungen wie kontinuierliche Verzuckerung, verbesserte Steuerungstechniken und bestimmte Enzym‐Verfahren in Verbindung gebracht. Abschließend wird eine kurze statistische Betrachtung angestellt und vorausgesagt, daß eine wesentliche Ausweitung der Stärkeverzuckerung von landwirtschaftlichen Strukturen und insbesondere von der Verwendung als Basis für chemische Syntheseprodukte abhängt.
Zentrifugalseparatoren in der Biotechnologie
Authors: Hemfort H. , Kohlstette W.
Published: November 2006

Bioprodukte sind Erzeugnisse lebender Zellen. Ihre Produktion erfolgt in Fermentern. Zur anschließenden Aufbereitung und Isolierung werden gewöhnlich eine Reihe von Methoden der mechanischen Trenntechnik kombiniert. Die Zentrifugation und Filtration haben neben Ultrafiltration, Reverse‐Osmose, Kristallisation, Dialyse u. a. entscheidende Funktion in diesen Prozessen. Zentrifugalseparatoren haben ein breites Anwendungsfeld bei der Ernte der Mikroorganismen und bei der notwendigen Phasentrennung gefunden. Die für die verschiedenen Entwicklungsstufen biotechnologischer Prozesse typischen Ablaufdiagramme werden beschrieben und die dazugehörenden Zentrifugenanlagen gezeigt (z. B. zur Hefe‐, Mononatriumglutamat‐, Einzellerprotein‐Gewinnung, zur Waschmittelenzyme‐, Glucoseisomerase‐ und Antibiotika‐Gewinnung). Auf die Gewinnung von Bioprodukten aus manipulierten Zellen wird hingewiesen.
Steeping of Barley Starch. Effects on Physicochemical Properties and Functional Characteristics
Authors: Lorenz K. , Collins Fort , Kulp K.
Published: November 2006

Starches isolated from 3 barley varieties (Glacier, High‐amylose Glacier, Waxy Compana) were steeped at 25°, 40° and 50°C for 1 and 3 days. Enzyme susceptibilities, water binding capacities, swelling powers, solubilities and gelatinization temperatures were determined. The extent of change in physicochemical properties due to steeping varied with type of barley starch. Generally, gelatinization temperature increased and the range narrowed as the temperature and the duration of incubation at a specific temperature increased. Swelling power was inversely related while solubility was directly related to amylose content. The treatment had little effect on swelling powers but restricted solubilities. Steeping of Glacier and Highamylose Glacier barley starches produced a more pronounced V‐pattern indicating increased amylose‐lipid interaction. Cakes baked with Glacier barley starches treated at 25° and 40°C up to 3 days were acceptable; starch treatment at 50°C caused collapse of cakes. Starch treatment caused high initial consistencies of fillings which were reduced during storage.
A Comparison of the Molecular Properties of Sorghum Starches of Different Origins
Authors: Craig S. A. S. , Stark J. R.
Published: November 2006

The molecular properties of three sorghum starches and their components have been compared by methods involving iodine staining, enzymic degradation and gel chromatography. The starches from the red and chalky varieties were very similar in properties and in amylose to amylopectin ratio, but differed in their molecular weight distribution profiles. The waxy sorghum starch was fractionated by the thymol‐butanol method to yield a small quantity of amylose. The three starch samples were all resistant to dissolution in boiling water but when subjected to physical damage the granules became partly soluble in cold water and almost totally soluble in boiling water.
A Study of Hydroxyethyl Starch. Part II. Degradation‐Sites of Hydroxyethyl Starch by Pig Pancreas α‐Amylase
Authors: Yoshida M. , Kishikawa T.
Published: November 2006

The degradation sites of hydroxyethyl starch (HES) by pig pancreas α‐amylase were determined by gas liquid chromatography. As a result, it was confirmed that HES could be hydrolyzed by α‐amylase only at the glucosidic bond of unsubstituted glucose residues, but not at the bond of 2‐0‐, 3‐0‐, and 6‐0‐hydroxyethylglucose residues. Furthermore, it was suggested that the enzymic degradation rate of HES could be well determined by measuring the reducing power.
Wheat Starch Pasting Measured with a “Minipaster”
Authors: Dengate H. N. , Meredith P.
Published: November 2006

A Minipaster apparatus, based on a Haake Rotary Viscometer, was developed to investigate thermal pasting of aqueous starch suspensions, and to study the effects of varying heating rate, holding time and holding temperature, and of varying starch concentration. Comparison has been made with a Brabender Visco‐amylograph. Attention is drawn to the marked serial dependence of the simple pasting parameters, peak viscosity temperature, peak viscosity, breakdown viscosity and setback viscosity. Relative breakdown and setback, and various ratios of pasting parameters are not markedly superior to the simple parameters as discriminants between starches.
100 Jahre Institut für Stärke‐ und Kartoffeltechnologie
Authors: Kempf W.
Published: November 2006

In dem vorliegenden Beitrag wird über die geschichtliche Entwicklung des Instituts für Stärke‐ und Kartoffeltechnologie in Detmold sowie seiner Vorgänger in Berlin und Detmold in den vergangenen 100 Jahren berichtet, nachdem im Jahre 1883 in dem an der Berliner Invalidenstraße gelegenen Gebäude der Landwirtschaftlichen Hochschule das Laboratorium des Vereins der Stärkeinteressenten in Deutschland gegründet worden war, das 14 Jahre später in den Neubau des Instituts für Gärungsgewerbe in der Seestraße verlegt wurde. Dabei werden die politischen, militärischen und wirtschaftlichen Ereignisse aufgezählt, welche die wechselvolle Entwicklung des Instituts in den folgenden Jahrzehnten besonders nachhaltig beeinflußt haben, sowie die Persönlichkeiten genannt, die für den Aufbau und Ausbau des Instituts von entscheidender Bedeutung gewesen sind. Von diesen verdienen die bisherigen neun Leiter besondere Erwähnung, deren Arbeiten, Leistungen und Erfolge stellvertretend für sämtliche Mitarbeiterinnen und Mitarbeiter beschrieben werden.
Some Properties of the Stem and Pollen Starches of Rice
Authors: Blakeney A. B. , Matheson N. K.
Published: November 2006

Starch was isolated from rice stems, pollen and grain. The stem starches in all varieties were similar and their amylose contents were not correlated with those of the endosperm starches. However, the amylose content of the pollen starches reflected that of the endosperm starches.
Purification of a Bacillus thermoglucosidius Exo‐oligo‐1, 6‐glucosidase by a Simple and Rapid Four‐step Method
Authors: Suzuki Y. , Kano Y. , Nishimura N.
Published: November 2006

A p‐nitrophenyl‐α‐D‐glucopyranoside‐hydrolyzing exo‐oligo‐ 1,6‐glucosidase (dextrin 6‐α‐glucanohydrolase, EC. 3.2.1.10) of a thermophile Bacillus thermoglucosidius was purified to an electrophoretically homogeneous form with a yield of 47% by a rapid and simple four‐step procedure including the enzyme desorption from immunoadsorbents by 3‐M NaSCN. Its specific activity was 421 μmol p‐nitrophenyl‐α‐D‐glucopyranoside hydrolyzed/min/mg protein at 60° C and pH 6.8. The aminoterminal amino acid of the enzyme was determined as methionine.
Synthesis of Amylases by Mixed Cultures of Different Strains of Moulds
Authors: Fiedurek J. , Llczuk Z. , Paszczynski A.
Published: November 2006

Twenty mould strains belonging to 13 species were used to determine the effect of mixed cultures on the synthesis of amylases. In test‐tube microcultures on a rotary shaker 110 pairs of combinations of these strains were studied. In 73 cases they dominated in their amylolytic activity over the weaker strain components in the culture, and in 21 cases also over stronger amylolytic components. Among six strain pairs selected for a more accurate evaluation all showed a higher glucoamylase activity in mixed cultures in comparison with an amylolytically less active component of the culture, and in four cases also in relation to a more active component.
Corn Hull Hydrolysis Using Glucoamylase and Sulfuric Acid
Authors: Osborn D. , Chen L. F.
Published: November 2006

Corn hull from a wet milling process contains 23% starch, 38% hemicellulose, 11% cellulose, 11.8% protein, 1.2% ash, and minor constituents. The starch fraction can be completely hydrolyzed by glucoamylase after the hull is heated with steam for 5 min. The hemicellulose fraction of destarched hull can be further hydrolyzed by sulfuric acid with a solid‐acid ratio of about 30 to 1 and a liquidsolid ratio of about 3 to 1. A process based upon the above findings yields 49 lb. of fermentable sugar (xylose + glucose) per 100 lb. of dry corn hull. The product does not inhibit yeast fermentation.
Glucose Isomerase Immobilized on SiO2‐Carrier with High Productivity
Authors: Weidenbach G. , Bonse D. , Richter G.
Published: November 2006

Subject is a glucose isomerase immobilized on a SiO2‐carrier of defined structure which achieves a productivity of 1: 22000 (22 t TS [42% fructose] per kg enzyme) on standard process conditions. The process parameters (degree of isomerization, temperature, pH‐value, cofactors) as well as inhibitors will be discussed with regard to activity and productivity. The process example shows, that reactors only with a very small column volume are needed because of the high productivity in the isomerization plant. The process is suited for a large‐scale production of isoglucose (HFS).
Highly Soluble β‐Cyclodextrin Derivatives
Authors: Szejtli J.
Published: November 2006

β‐Cyclodextrin is an inclusion complexing agent produced on industrial scale. The low solubility of its complexes is a serious disadvantage in many cases. Substituted β‐Cyclodextrin derivatives are characterized by much higher solubility. Among methylated derivatives the heptakis‐di‐O‐methyl‐β‐Cyclodextrin deserves special attention. In its aqueous solutions many poorly soluble or practically insoluble compounds can be dissolved, whereas the solubility enhancement factor is between 3 and 1 200 depending on the substance. Aqueous injectable solutions can be prepared from highly lipophilic compounds, enzymatic reaction rate of lipophilic substrates can be strongly accelerated, biological absorption of drugs or fat‐soluble vitamins can be enhanced and vaccine production can be augmented up to 100‐fold. Methylated cyclodextrins are able to act as solvents by forming watersoluble inclusion complexes and as phase‐transfer catalysts at free radical polymerization. Low molecular cyclodextrin‐polymers with molecular weight between 2 000 and 10 000 behave similarly. They are very well soluble, retaining their complexing ability. On account of the macromolecular character the diffusion of dissolved and complexed substances is considerably decelerated. By including into a chiral cavity the entrapped molecules become optically active oriented, and therefore their reactions are sterically controlled.
Kinetics of the Benzylation of Potato Starch
Authors: Free H. W. Homan , Joosten G. E. H. , Roelfsema W. A. , Stamhuis E. J.
Published: November 2006

The formation of benzyl ethers of potato starch by etherification with benzyl chloride is base catalyzed and is therefore carried out at high pH. In a suspension of starch granules the rate of starch ether formation is found not to be linearly related to the concentration of hydroxyl ions in the water phase of the suspension. At the same pH widely different rates of reaction can be observed, to be due to the tendency of the starch granules to “absorb” hydroxyl ions when electrolytes are added to the suspension. The rate of formation of the benzyl ether of starch is found to be linearly related to the amount of hydroxyl ions “absorbed” by the starch. The rate of the side reaction leading to benzyl alcohol turned out to be higher in the presence of starch than in water of the same pH.
Cooperative Test on Amylography of Milled‐Rice Flour for Pasting Viscosity and Starch Gelatinization Temperature
Authors: Juliano B. O. , Perez C. M. , Alyoshin E. P. , Romanov V. B. , Bean M. M. , Nishita K. D. , Blakeney A. B. , Welsh L. A. , Delgado L. L. , El Bayâ A. W. , Fossati G. , Kongseree N. , Mendes F. P. , Brilhante S. , Suzuki H. , Tada M. , Webb B. D.
Published: November 2006

An ICC cooperative test on Amylograph viscosity of milled‐rice flour involving 11 laboratories and 4 contrasting rice samples was undertaken to determine the reproducibility of the method. The highest contribution to total variance was from sample followed by laboratory and then sample x laboratory. Only 2 of 9 laboratories showed similar peak viscosities on the samples, only 3 of 8 laboratories had similar cooked paste final viscosities, but none of 7 laboratories had similar cooled paste final viscosities using preground flour and a common method. Use of individual mills to prepare flour for the common method and use of laboratory method with preground flours increased variance due to laboratory and reduced the contribution of sample. Final gelatinization temperature of starch may be readily estimated from the apparent temperature of 20 BU intercept of the Amylograph curve of 20% preground paste from the results of 5 laboratories with 700 g · cm cartridge.
Technological Potential of Some Starch Degrading Yeasts
Authors: Guerzoni M. E. , Lambertini P. , Lercker G. , Marchetti R.
Published: November 2006

The possibility of obtaining lipids for alimentary or pharmaceutical use from starch degrading oleaginous yeasts was considered. The yeast strains, belonging to different species, were selected on the basis of two purposes: (a) microbial conversion of starch in fat material for human consumption; b) production of useful and rare single lipidic fractions such as phospholipids or unusual fatty acids. We worked with two groups of yeasts characterized by two patterns of lipid composition when grown on starch: one capable of accumulating high amounts of total lipids, up to 60–70% of dry weight, and the other capable of synthesizing a large amount of phospholipids. In the first group the phospholipids/triglycerides ratio was only slightly affected by the cultural conditions; in the second group this relationship was not only strongly influenced by the carbon/nitrogen ratio and nitrogen source but also by the rate of starch hydrolysis. In fact the amylase induction phase of the strains was found to be one of the most important factors determining the composition of the lipidic fraction. In the study of regulatory mechanisms controlling the synthesis of the phospholipids and triglycerides in the cells, mutants altered in the lipids biosynthesis and producing increased amounts of phospholipids were also employed.
Rheological Properties of Certain Processed Rice Products
Authors: Chinnaswamy R. , Unnikrishnan K. R. , Bhattacharya K. R.
Published: November 2006

Two popular rice products, namely expanded rice and flaked rice, are prepared from parboiled rice. As about 90% dry weight of milled rice is starch, the behaviour of rice and its products reflects largely the behaviour of its starch. The above precooked rice products which undergo a high degree of thermal and/or mechanical treatment during processing have a high degree of gelatinization and display therefore properties like those of pregelatinized starch. Both expanded rice and flaked rice have high water binding capacity and cold‐swelling properties. Under suitable moisture conditions they undergo retrogradation and show reduced hydration and viscosity. Normal steam‐parboild rice shows much lower viscosity because of a comparatively low degree of starch gelatinization during processing and its subsequent retrogradation. Rheologically the cold slurry of these products indicates a thixotropic system demonstrating time dependent thinning. Further, a dependence on slurry concentration and degree of processing and a yield value behind a certain concentration were also apparent. The cold swelling properties of flaked rice and expanded rice show potential use of their flour as a possible subsitute for pregelatinized starch in food and other industries.
Carbohydrate Make Up of Green, Fully Ripened Pods and Seeds of Leucaena leucocephala
Authors: Arora S. K. , Joshi U. N.
Published: November 2006

The chemical composition of the green, fully ripened pods and seeds of Leucaena leucocephala shows some variation in their nutrient contents in different genotypes. Green pods are a rich source of protein and well comparable with the protein content of leguminous seeds. The structural carbohydrate varies significantly. Green pods are of dual importance to supply fibre and nutrients. The empty fully ripened pods are fibrous. The seeds, besides having rich protein content, have 20 – 25% galactomannan gum which has the potential to be used as a laxative and in vegetable soups. Mimosine content is higher in the green pods, but it is thermolabile.
Probleme der gelchromatographischen Molekulargewichtsbestimmung von Stärkemolekülen
Authors: Klingler R. W.
Published: November 2006

Die Gelpermeationschromatographie (GPC) an porösem Glas (CPG) unter Einsatz eines Differentialrefraktometers ist ein schnelles und vorteilhaftes Verfahren zur Fraktionierung und Charakterisierung von Biopolymeren. Im Rahmen dieser Arbeit wird über die Erfahrungen und die Probleme mit dieser Analysentechnik bei der Untersuchung der Molekülgrößenverteilung von nativen und modifizierten Stärken berichtet und der Einfluß der experimentellen Bedingungen auf das Elutionsverhalten dargestellt. Es wird gezeigt, daß die Anwendbarkeit des Verfahrens und die Aussagekraft der Ergebnisse vom Stärketyp, von der Löslichkeit der Stärke, von der Trenncharakteristik sowie von der Eichung der Säule abhängen.
An ESR Spin Probe Study of Potato Starch Gelatinization
Authors: Windle J. J.
Published: November 2006

Potato starch granules in excess water exhibit three distinct starch‐water stages between approximately 25° to 50°C, 50° to 70°C, and 70° to 90°C corresponding to a pre‐gelatinization, a gelatinization and a post‐gelatinization stage, respectively. The mobility of the absorbed water and the starch‐water interaction in the first two stages depends strongly upon the initial state of hydration of the granules. By the end of the gelatinization stage, the mobility of the water in the gel is the same regardless of the initial state of hydration of the granules. Upon cooling to room temperature the mobility of the gel water decreases to a corresponding viscosity of about an order of magnitude greater than for liquid water.
Production Methods of D‐Mannitol
Authors: Makkee M. , Kieboom A. P. G. , van Bekkum H.
Published: November 2006

The present commercial production of D‐mannitol, a valuable nutritive sweetener, takes place by hydrogenation of 1:1 D‐glucose/D‐fructose mixtures over nickel. The low D‐mannitol yield (25 — 30%), however, asks for the development of alternative procedures. A literature survey of the various production methods is given, including some other possible combinations of known procedures. It is concluded that the simultaneous use of glucose isomerase and copper‐on‐silica (combi‐process) is a promising procedure for the preparation of D‐mannitol from D‐glucose or D‐glucose/D‐fructose syrups.
Enhanced Digital Control of a Mechanical Recompression Evaporator in a Modern Fructose Refinery
Authors: Dietrich D.
Published: November 2006

Fixed‐speed, motor‐driven recompression evaporators are inherently more difficult to bring up from a cold start than variable speed turbine‐driven ones. They also need more careful operator attention during throughout changes. These difficulties are mostly caused by the choking action of the motor driven compressor's main control device the variable turbine‐inlet guide vanes. Compression of fugitive water vapors so far suffers from another problem not encountered during turbo‐compression of gas or air: no reliable simple flow element for compressor discharge is in general use. Thus standard compressor surge control schemes involving measured flow will not work. The method presented involves a two‐tier hierarchial control scheme. The usual flow, pressure, temperature and density loops are directly controlled by electronic analogues of P‐I‐D‐controllers, some even having conventional cascade linkages. Those P‐I‐D‐controllers, in turn, have their setpoints coordinated by a supervisory master computer as though they were all cascaded. The results of the control scheme are intended to the following:

Increased safety during start‐up because not only guide ‐vane opening but also heat‐up and purge‐out are monitored via a consistent algorithm, not left to an operator's whim.

Reliable and safe turn‐down capability of the evaporator over a range of from full to about 1/3 design capacity.

Reduced need for operator attention since the control scheme will handle most plant upsets by itself.

It was mostly the latter of the hoped‐for advantages which prompted development of the method, since the user wanted to keep down the number of highly trained process operators needed to man the centrally‐located control room of the syrup refinery.
Studies on the Functional Characteristics and Digestibility of Starches from Phaseolus vulgaris Biotypes
Authors: Hoover R. , Sosulski F.
Published: November 2006

The functional properties of starches from black bean, kidney bean, navy bean, northern bean and pinto bean, all biotypes of Phaseolus vulgaris, were examined. Starch granule sizes ranged from 22 – 39 μm (length) to 19 – 28 μm (width) and shapes varied from elliptical to oval. Amylose content ranged from 30.2 – 37.3%. A highly ordered crystalline structure of granules (Ca) was suggested by restricted swelling power and solubility, resistance to α‐amylase attack, high gelatinization temperature and stable amylographic viscosities. Moreover, the existence of a crystalline structure of the highest and lowest order of stability among the Phaseolus starches was indicated for pinto bean and black bean, respectively, which were substantially different than those of kidney, northern and navy bean. The higher stability of pinto bean starch indicated a higher degree of associative bonding forces, namely, hydrogen and covalent, between oxygen and hydrogen atoms of closely packed parallel amylose chains. The wide range in amylographic viscosities was a reflection of crystalline stability, amylose exudation, granule swelling and pH of slurry. Gels exhibited a higher degree of retrogradation at +4 °C than at – 15 °C. Scanning electron microscopy showed that α‐amylase‐treated corn starch granules were degraded from the inside out by the formation of large circular holes, whereas those of kidney bean were less extensively degraded and showed only scaling and roughening of the surface as evidence of granule deterioration.
Preparation and Calcium Complexation Properties of a Series of Oxidized Polysaccharides. Structural and Conformational Effects
Authors: Nieuwenhuizen M. S. , Kieboom A. P. G. , van Bekkum H.
Published: November 2006

A number of polysaccharides of the starch type, including maltodextrins and cyclodextrins and some other well‐known polysaccharides have been oxidized by periodate/chlorite (two‐step method) or hypochlorite (one‐step method), yielding ring‐opened polycarboxylates. The oxidation products from the starch type show by far the best calcium complexing properties and have potential application as phosphate substitutes in detergent formulations.

A relatively sharp increase in calcium complexing ability is observed at a degree of polymerization of about ten, whereas just a slight further improvement occurs at higher degrees of polymerization. This phenomenon is explained by the formation of helix structures which contain efficient Ca(II) complexing sites. This idea is supported by 17O NMR measurements showing that oxidized starch type compounds with m > 10 behave as heptadentate ligands.
Structural Characteristics of Gelatinized Starch
Authors: Varriano‐Marston E. , Zeleznak K. , Nowotna A.
Published: November 2006

Descriptions and interpretations of gelatinized starch structure are dependent on electron microscopical sample preparation techniques. Complete destruction of starch granule integrity is effected by slow freezing and fast drying procedures. Fast freezing rates and controlled sublimation of ice are necessary for maximum structural preservation. Solvent dehydration methods produce a film on gelatinized starch granule surfaces so that their porous nature is not revealed. In addition, agglomeration and compaction of the fine fibrous network of starch exudate is effected by solvent dehydration techniques.
Bestimmung der funktionellen Gruppe und des durchschnittlichen Substitutionsgrades von Carboxymethylstärke
Authors: Kessel H.
Published: November 2006

Für die Charakterisierung chemisch modifizierter Stärkederivate ist die Kenntnis ihres Anteiles an funktionellen Gruppen erforderlich. Bei der Carboxymethylstärke ist es die CH2COONa‐Gruppe, deren molare Relation zu den Glucose‐Einheiten des Stärkemoleküls den durchschnittlichen Substitutionsgrad ergibt.

Mit der vorliegenden, für die Fabrikationskontrolle ausgearbeiteten Analysenmethode wird die CH2COONa‐Gruppe der Carboxymethylstärke durch Fällung ihres Kupfersalzes und Rücktitration des überschüssigen Kupfers im Filtrat mit Ethylendiamintetraacetat gegen Murexid‐Indikator bestimmt.
Cyanoethylated Starch Thickeners as Substitutes for Sodium Alginate in Printing with Reactive Dyes
Authors: Hebeish A. , Abdel‐Thalouth I. , Ibrahim M. A. , Elzairy M. R.
Published: November 2006

Cyanoethylated starches were prepared by reacting rice starch with acrylonitrile in presence of sodium hydroxide. The suitability of the modified starches in printing cotton fabrics with reactive dyes was investigated through application of pastes containing cyanoethylated starches and reactive dyes to cotton fabric, fixation of the prints by steaming or thermal treatment, assessment of colour strength and overall fastness properties of the prints, examination of rheological properties and carrying out parallel experiments using sodium alginate, unmodified starch and alkali‐treated starch. Cyanoethylated starches particularly that containing 1.75% N proved to be a potential thickener for printing cotton with reactive dyes.
A Comparative Study of the Effect of Acetylation on Starches of Phaseolus vulgaris Biotypes
Authors: Hoover R. , Sosulski F.
Published: November 2006

Enzyme hydrolysis, X‐ray diffraction, differential scanning calorimetry and Visco/Amylo/Graphy were used to examine the strength of associative bonding forces between starch chains of native legumes. Addition of acetic anhydride resulted in unequal degrees of substitution. Scanning electron microscopy revealed no differences between the external morphology of native and acetylated starches. Similarities in the X‐ray diffraction patterns of native and acetylated starches indicated that acetyl groups mainly entered the amorphous regions. On acetylation, decreases in starch hydrolysis, gelatinization temperatures, enthalpies of gelatinization, extent of viscosity increase during the holding period at 95°C and syneresis, and increases in 95°C viscosity, set‐back and amylose exudation were observed. It appeared the extent of distribution of the acetyl groups between the amylose and the amorphous regions of the amylopectin fraction varied among legume biotypes, and differences existed between legume starches with regard to the ratio of the concentration of the acetyl group at the 2—O position relative to that at 6—O.
Characterization of Pinhão Starch. Part II. Rheological Properties of the Pastes
Authors: Cereda M. P. , Wosiacki G.
Published: November 2006

Pinhão starch paste shows a viscoamylographic pattern that is not usual for cereal or tuber sources, being more closely related to leguminosae starches. The gel is highly resistant to heat and mechanical stirring and it shows a relatively low retrogradation. There is no peak viscosity and the gel is not easily cooked. The opacity is similar to that of cassava starch paste, when hot, and to that of corn, in cold conditions. Viscoelastic characteristics of the paste show a short‐bodied behaviour, more similar to corn starch paste, although some elasticity may be clearly observed. The rheological properties of this starch make it a potential additive for blending with other starches, mainly for use in some processed acid foods submitted to cold storage.
A Comparison of the Susceptibility of Two Commercial Grades of Wheat Starch to Enzymic Hydrolysis and their Resultant Oligosaccharide Product Spectra
Authors: Atkins D. P. , Kennedy J. F.
Published: November 2006

Solutions of two commercial fractions of wheat starch, which are separated by their granule size, have been found to differ both in their susceptibility to hydrolysis by α‐amylase and in the oligosaccaride spectra of their resultant hydrolysates. These effects have been ascribed to a reduced proportion of amylose and a higher degree of (1 → 6) branching identified in the starch of the smaller granules.
Changes in Crystallinity and Gelatinization Phenomena of Potato Starch by Acid Treatment
Authors: Komiya T. , Nara S.
Published: November 2006

The hydrolysis of potato starch by 1‐N H2SO4/30% ethanol aqueous solution at 45°C increased linearly with increasing of hydrolysis time for 14 d. The relative crystallinity of native starch showed 0.343 and 0.350 by symmetrical reflection and transmission techniques, resp. The increasing ratio of relative crystallinity to hydrolysis time corresponded very closely with that of 1/hydrolysis residue up to 14 d. These facts suggest that only the amorphous region of the starch granules will be hydrolyzed by the acid. By differential scanning calorimetry the calorimetric enthalpy of potato starch containing about 200% moisture content was found to stay largely unchanged by acid treatment for 6 d. The swelling power at 70° and 80°C of potato starch reached to the minimum value and, moreover, from the gel‐chromatogram patterns of the acid‐treated starches, the crystalline region of the starch granules may begin to deteriorate slightly by acid treatment for more than 6 d, although the relative crystallinity by the X‐ray diffraction method increased slightly with passing of hydrolysis time.
Analytical Remarks to Explain Some Discrepancies in the Determination of Dry Matter and Starch from Potato Tubers Density
Authors: Samotus B. , Leja M. , Scigalski A. , Dulinski J. , Siwanowicz R.
Published: November 2006

1) Air adsorbed on potato tuber surface can result the accidental error, decreasing the true value of tuber density. Some deviations from normal temperature do not seem to change substantialy the tuber density.

2) The dry matter determination should be precisely reexamined in a special series of experiments. The improper method can introduce a systematic error, increasing or decreasing the results.

3) It is necessary to compare mostly used methods of starch determination in potato tubers and to estimate the possible systematic errors.

4) The various slope of the regression line: dry mater/starch vs. potato density, can be resulted by different factors as follows: the variable intercellular spaces, the proportional systematic errors in analytical determination, the variable dry matter density, and increasing (or decreasing) value of non‐starch substances.

5) The intercellular spaces can result either a constant or a proportional systematic errors in the tuber density determination. They can be eliminated by vacuum infiltration procedure, which should be, however, verified.

6) The dry matter determination seems to be difficult analytical problem and it has not been definitely solved until now.

7) The Maercker's constant has been until now an open question and its variability should be verified from analytical point of view.
Extrusion Cooking in Enzymatic Liquefaction of Wheat Starch
Authors: Reinikainen P. , Suortti T. , Olkku J. , Mälkki Y. , Linko P.
Published: November 2006

Wheat starch was treated for gelatinization, partial liquefaction, and subsequent further hydrolysis by extrusion cooking together with a thermostable Bacillus licheniformis α‐amylase followed by batch incubation of the extrudates at 80°C. The degree of hydrolysis depended on the extrusion feed moisture content, enzyme concentration, mass temperature during extrusion cooking, and the length of the counter screw elements. The degree of hydrolysis was followed both by dextrose equivalent and by molecular weight distribution pattern as determined by high performance gel permeation chromatography. A reaction velocity model was shown to fit well to the kinetic data obtained. The enzyme was only incompletely inactivated by mercuric chloride suggesting the presence of also other than sulfhydryl dependent amylase.
Isosorbide. Preparation, Properties and Chemistry
Authors: Flèche G. , Huchette M.
Published: November 2006

Isosorbide is obtained by dehydration of sorbitol and therefore can be considered as a valuable product from biomass. The acid‐catalyzed reaction gives rise to different anhydro‐compounds, but also to polymer‐like products. Kinetics of sorbitol decrease, followed with the help of HPLC, shows, remarkedly, the different reactions taking place during the dehydration. Physiocochemical properties of isosorbide are also discussed: melting temperature, specific gravity, solubility. Emphasis is put on stereochemistry aspect, pointing out the endo‐exo position of hydroxyl groups versus those of other isomers: exo‐exo for isoiodide and endo‐endo for isomannide. Some other properties such as: hygroscopicity ant thermal stability are also discussed. The chemical reactivity of the molecule is then described and some reactions analyzed, proving the interest of the cyclic conformation. Finally, a review of known applications is presented.
Thiosemicarbazones of Starch Dialdehyde and Their Biological Activity
Authors: Barabasz W. , Chociej J. , Kenit A. , Tomasik P.
Published: November 2006

Starch dialdehyde thiosemicarbazones of various degree of substitution were prepared and their biological activity studied against some saprophytes, fungi and Mycobacterium tuberculosis.
A New Regenerable Immobilized Glucose Isomerase
Authors: Antri R. L. , Auterinen A.‐L.
Published: November 2006

A new, immobilized glucose isomerase high productivity has been developed for isomerization of glucose into high fructose syrups. Soluble glucose isomerase fromStreptomyces rubiginosusis highly purified and electrostatically adsorbed onto a granular DEAE‐cellulose comprised of fibrous DEAE‐cellulose, food grade polystyrene and titania. The same enzyme on fibrous DEAE‐cellulose has been in commercial use in the United States since 1968. Because the soluble enzyme is electrostatically adsorbed to the carrier, the immobilized enzyme can be regenerated after use and the carrier reloaded with fresh soluble enzyme. Regeneration and reimmobilization can be repeated several times thus providing a minimum cost enzyme‐carrier system. The enzyme is tightly bound to the carrier during isomerization. The immobilized isomerase is compatible with bisulfite in the substrate sufficient to stabilize the enzyme and provide a degree of protection against infection at low isomerization temperature. High purity and high specific activity of the soluble enzyme make possible high activity levels for the immobilized enzyme with potencies of up to 1500 IGIU/g. There occurs essentially no elution of color from the immobilized enzyme during start up of isomerization. Due to the combination of low compressibility of the particles and high immobilized activity, productivities greater than 9 metric tons of 42% fructose syrup solidsPerkg of immobilized enzyme are being achieved on a commercial scale.