bluuebunny/crossref_metadata_2025 huggingface dataset:
The Automatic Control of Starch Drying Process
Authors: Boruch M. , Brzeziński S. , Pałlka A. , Pierzgalski T.
Published: November 2006

The way of automatic control of potato starch drying by means of steering revolutions of vacuum dehydrator has been worked out and described. A special electronic worm sensor for the continuous measurement of starch humidity has been designed and constructed. Humidity of starch was determined by measurement of its conductance. The influence of temperature upon the humidity measurement was compensated in an electronic system by means of a thermistor. The system for automatic control of starch drying is characterized by the following parameters: measuring range 17–23% H2O; accuracy of measurement and control of humidity η0.3% H2O.
The Effect of Monoglycerides on Amylose Complexing During a Potato Granule Process
Authors: Hoover R. , Hadziyev D.
Published: November 2006

Palmitic and stearic acid types of commercially available monoglycerides were assessed for their ability to complex amylose in a simulated Add‐Back potato granule process. Monoglycerides, applied as hydrated gels (pH 2.3–7.1) and microbead powders, had α‐ and ß‐crystal forms, respectively, as proved by x‐ray diffraction and IR‐spectroscopy. Their ability to complex amylose was followed by determining the complexing index of model systems consisting of lintnerized starch, starch grains or whole potato tissue subjected to semipilot scale precooking, cooling, steam‐cooking and mash‐mixing steps. The α‐form and the palmitic acid type of monoglyceride were superior for amylose insolubilization. SEM micrographs were used to determine the effect of added monoglycerides on the extent of amylose leaching and on heated starch grain integrity.
Some Properties of Whole‐Cell Glucose Isomerase Immobilized in Polyacrylamide Gel by Radiation
Authors: Bachman S. , Gębicka L. , Gasyna Z.
Published: November 2006

The whole‐cell glucose isomerase was immobilized by the method of block polymerization of acrylamide initiated by 60Co irradiation. Some properties of immobilized glucose isomerase were studied under various reaction conditions, in respect of its use as industrial catalyst. It was established that Co2+ ions did not increase stability of the immobilized enzyme at pH above 8.0. The half‐life of the immobilized glucose isomerase was found to be 24 days at 60°C.
Production and Physico‐chemical Properties of Isomerized Glucose Syrups I. Sweetness
Authors: Dziedzic S. Z.
Published: November 2006

Glucose syrups of 21, 45, 65 and 100% D. E. were isomerized using a Novo Sweetzyme isomerase over 24 h. The reaction was followed by high‐pressure liquid chromatography (hplc). Syrups with 49–52% isomerized glucose syrups were obtained. The sweetness of the glucose syrups was determined before and after isomerization in terms of threshold, and relative sweetness to a 5% sucrose standard solution at varying concentrations. Significant increases (up to two‐fold) were shown for both high and low D. E. syrups upon isomerization.
A Study on the Condensation of Sorbose with Acetone: Catalysis by Macroporous Ion Exchange Resins
Authors: Nair P. R. M. , Shah P. M. , Sreenivasan B.
Published: November 2006

A study on the condensation of L‐sorbose with acetone to form 2,3‐4,6‐di‐o‐isopropylidene sorbose (diacetone sorbose, DAS) in the presence of various macroporous cationic exchange resins (sulfonic acid type based on styrene and divinyl benzene copolymers) has been carried out. The condensation rates were found to be dependent on the characteristics of the resins such as surface area and percent crosslinking. The formation of DAS was found to increase with increase in temperature and decrease with increase in particle size of the sorbose. On continuous use of the resins in the reaction the catalytic activity is found to decrease.
Starch Lipids: A Reappraisal
Authors: Morrison W. R.
Published: November 2006

It is proposed that lipids on the surface of starch granules should be called “starch surface lipids”, and that those inside the granules should be called “internal starch lipids”. Starch surface lipids appear to be derived from the “non‐starch lipids” which are either free or bound to proteins in the starch‐bearing tissues. In cereals the internal starch lipids are exclusively monoacyl lipids, and they are quite different in composition from the starch surface lipids and non‐starch lipids. In some recent publications lipids purporting to be internal starch lipids evidently include substantial quantities of non‐starch or surface lipids.
Differential Scanning Calorimetry Studies on the Crystallinity of Ageing Wheat Starch Gels
Authors: Longton J. , Legrys G. A.
Published: November 2006

The ageing of wheat starch gels stored at 4°C, 21°C and 30°C was examined by differential scanning calorimetry. Kinetics of the crystallisation process were studied using the Avrami model where it was found that the experimental data fitted the model more satisfactorily when the Avrami exponent was less than unity. At higher storage temperature the starch crystals appeared more symmetrically perfect. Addition of wheat flour pentosans to 50% starch gels did not significantly affect the kinetics of ageing. The extent of crystallisation during the ageing process depends on the moisture content of the starch gel. Crystallinity of the starch gel, measured in the temperature range 306–346°K does not occur if the solids content is below 10% or above 80% and a bell shaped curve is obtained. Reduction of the moisture content of the starch fraction of baked goods either directly or indirectly using materials competing for water, might therefore reduce the staling problem.
Role of Lactic Acid in Corn Steeping and Its Relation with Starch Isolation
Authors: Roushdi M. , Fahmy A. A. , Mostafa M.
Published: November 2006

Corn grains were steeped in fresh SO2 solution (300 ppm), old SO2 solution (100 ppm, 0.55 g lactic acid per 100 ml) and fresh SO2 with chemically pure lactic acid (100 ppm SO2 + 0.55 g lactic acid per 100 ml). The water absorption rate in all trials using old SO2 or low SO2 with lactic acid in the first stage of the steeping process was higher. The solubilization and diffusion of protein was stronger in corn grains steeped completely in old SO2 or low fresh SO2 with lactic acid. Such treatments gave the highest starch recovery with lowest protein content in the isolated starch. The low starch content in hulls and fibers confirms the important role of lactic acid in presence of a low concentration of SO2 (0.01%).
Note on the Hydrolysis of Amylose by beta‐Amylase
Authors: Ghiasi K. , Hoseney R. C.
Published: November 2006

Amylose is thought to be a slightly branched polymer with a ß‐amylolysis limit of about 78%. Treating amylose with a mixture of the debranching enzyme pullulanase and ß‐amylase will give 100% conversion to maltose. Interesting one does not obtain 100% conversion if the enzymes are used sequentially. We have found that amylose retrogrades and becomes insoluble while being incubated with pullulanase. Minimum debranching time will give 100% ß‐amylolysis, which we think explains the previously reported need to use the enzymes simultaneously.
Biomasse — nachwachsende Energie
Authors: Schreier K.
Published: November 2006

Die Grenzen des Wachstums – die Erschöpfung der Energiequellen, insbesondere von Öl und Gas – die Koppelung von Wachstum und Energieverbrauch – die notwendigen Verschiebungen von Energiekonsum und Produktion aus den Industriestaaten in die Länder der Dritten Welt – die Umweltproblematik durch Intensivindustrialisierung – alle diese Probleme werden seit 15 Jahren, mit ständig steigender Intensität, von Technologen, Ökonomen und Ökologen vorgetragen, von Wirtschaft und Politik jedoch nicht, bzw. in einem viel zu geringem Ausmaß zur Kenntnis genommen. Heute ist festzustellen, daß durch das verspätete bzw. nicht erfolgte Einsetzen entsprechender Maßnahmen die Dimensionen der Energiekrise und ihr zeitlicher Verlauf bereits derart kritisch sind, daß eine evolutionäre Neuordnung unseres gesamten Wirtschafts‐ und Gesellschaftssystems immer problematischer, bzw. immer unwahrscheinlicher wird. Energie aus Biomasse ist neben der Atomenergie in den Industriestaaten eine mögliche Entlastung dieser kritischen Situation. Dies gilt sowohl für die Länder der Dritten Welt als auch für die Industriestaaten. Die Technologie für die Umwandlung von Biomasse ist weit fortgeschritten, weitere entscheidende Entwicklungsschritte, wie z. B. Cellulose‐Hydrolyse, sind in nächster Zeit zu erwarten. Die Produktion von Biomasse für Energiezwecke steht – im Gegensatz zur Umwandlungstechnologie – erst am Beginn der Entwicklung. Aus den gegebenen Randbedingungen heraus ist es notwendig, die Entwicklungsarbeiten für die Produktion von Biomasse rasch voranzutreiben. Neben Zucker‐ und Stärkepflanzen herkömmlicher Art müssen in den nächsten Jahren Zucker‐ und Stärkepflanzen mit hohem Energieinhalt und hoher Flächenleistung produziert werden. Besondere Bedeutung für die Energieproduktion in großen Dimensionen kommt unter unseren europäischen klimatischen Bedingungen aus Gründen der Lagerfähigkeit dem Körnermais zu. Für die Energieproduktion in kleinen Dimensionen (Energieversorgung der Landwirtschaft) müssen ausgewählte Fruchtfolgen als Rohstoffbasis dieser Betriebe herangezogen werden.
Characterization of Starch from Ginger Root (Zingiber officinale)
Authors: Reyes F. G. R. , D'Appolonia B. L. , Ciacco C. F. , Montgomery M. W.
Published: November 2006

Starch has been isolated from ginger root in 12.3% yield. The starch that contained 22.2% amylose had a density of 1.517 g/cm3 and an A type x‐ray diffraction pattern. Solubility studies revealed low swelling power and solubility in water, and reduced solubility in dimethyl sulfoxide and in potassium hydroxide, suggesting homogeneous and strong bonding forces maintaining the granular matrix. Information from the Brabender amylogram indicated a relatively high initial pasting temperature (80°C) and resistance to mechanical shear upon gelatinization, resembling, those starches modified by crosslinking.
Properties of Residual Starches of Sugary‐2 and Sugary‐2 Opaque‐2 Maize Following Amylase Hydrolysis
Authors: Ikawa Y. , Glover D. V. , Iida M. , Takaya T. , Fuwa H.
Published: November 2006

Properties of residual starches of sugary‐2 opaque‐2 and sugary‐2 maize starch granules hydrolyzed with glucoamylases were investigated. A crude and two crystalline glucoamylases were used. The amylopectin fractions of both starches hydrolyzed easier than that of amylose with all enzymes. Residual starches hydrolyzed by the crude glucoamylase accumulated low‐molecular weight materials, which was not observed in residual starches attacked by crystalline glucoamylase. It was suggested that in the crude enzyme the contaminating α‐amylase caused the accumulation of the minified fraction. It is also suggested that the crystalline region of sugary‐2 opaque‐2 starch may consist of a mixture of A‐type and B‐type patterns. Evidence for this was from observation of the changes in X‐ray diffraction patterns of residual starch following amylase and acid hydrolysis.
Untersuchungen über den Einfluß der organischen und mineralischen Düngung auf die Viskositätseigenschaften der Kartoffelstärke
Authors: Putz B.
Published: November 2006

Bei der Untersuchung der Frage, ob über die mineralische Düngung eine gezielte Kartoffelstärkequalität bereits auf dem Felde hergestellt werden kann, zeigte sich zunächst die besondere Bedeutung der Jahreswitterung, des Anbaustandortes und der Sorte für die Verkleisterungstemperatur, die Heißviskosität und die Kaltviskosität der Kartoffelstärke. Gegenüber diesen Einflüssen war derjenige der mineralischen Düngung minimal. Es zeigte sich, daß die Stärkequalitätsfaktoren nur langfristig über eine Anhebung des P2O5‐Gehaltes des Bodens in geringem Maße positiv beeinflußt werden können. Gezielte Stärkequalitäten lassen sich über die Düngung der Kartoffel somit nicht erzeugen. Daraus resultiert, daß Anbauer von Stärkekartoffeln die mineralische Düngung auf einen optimalen Knollen‐ und Stärkeertrag ausrichten sollten.
Änderung des Gehaltes an Phosphor, Calcium und Magnesium in Kartoffelstärke durch verschiedene Düngungsbedingungen
Authors: Miča B.
Published: November 2006

Die Qualität der Kartoffelstärke wird durch die Anwesenheit von Phosphor, Calcium und Magnesium beeinflußt. Daher ist es zweckmäßig, ihren Gehalt in der Stärke zu bestimmen. Da die Menge dieser Elemente in der Stärke offenbar durch die Düngungsbedingungen beeinflußt wird, wurden dreijährige Feldversuche entsprechend ausgewertet. Gegen Ende der Vegetation erhöhte sich der Phosphorgehalt in der Stärke. Ca‐ und Mg‐Gaben verminderten den Phosphorgehalt während der Reifephase. Die in den früheren Vegetationsabschnitten festgestellten größeren Unterschiede zwischen den Düngungsvarianten verminderten sich während der Reife. Änderungen im Calciumgehalt wurden durch unterschiedliche Düngungsbedingungen hervorgerufen. Zum Ende der Vegetation verminderte sich der Calciumgehalt der Stärke. In der Reifephase wurde im Durchschnitt auch ein geringerer Magnesiumgehalt in der Stärke festgestellt als in der Vollblüte. Im Vergleich zur Abblühphase wurde nur bei gemeinsamen Gaben von Ca und Mg eine Erhöhung des Magnesiumgehaltes festgestellt. Die Wirkung von Mg‐Gaben stand in enger Beziehung zur Höhe der N‐, P‐, K‐Gaben und zur Vegetationsphase.
Preparation and Evaluation of Hydroxyethyl Starch
Authors: El‐Hinnawy S. I. , Fahmy A. , El‐Saied H. M. , El‐Shirbeeny A. F. , El‐Sahy K. M.
Published: November 2006

Hydroxyethyl starches were prepared by reaction of potato and corn starches with ethylene oxide. The degree of substitution (DS) was determined by the acetylation method and was 0.02 to 0.20 per glucose unit. Determination of position of the alkoxyl groups by thin layer chromatography indicates that 85% of the groups were attached to C2. Periodic oxidation of the hydroxyethyl starch indicated decrease with the increase of DS due to the resistance of C2–3 substituted glycol to cleavage. The iodine adsorption decreased with increasing DS. Therefore iodine adsorption could be taken as a measure of the degree of modification of starch molecule.
Scanning Electron Microscopy of Enzyme Digested Varagu Starch Granules
Authors: Paramahans S. V. , Tharanathan R. N.
Published: November 2006

Amylolytic susceptibility of a native varagu starch granule was followed chemically and microscopically. Scanning electron microscopy revealed that attack by salivary α‐amylase resulted in a gradual erosion of the surface followed by granule penetration at certain locations. Attack by glucoamylase, on the other hand, was more uniform, and resulted in pitting and depressions all over the surface.
Cereal‐ and Root Starch Modification by Heat‐Moisture Treatment. II. Functional Properties and Baking Potential
Authors: Lorenz K. , Kulp K.
Published: November 2006

Functional baking properties of heat‐moisture treated starches (barley, triticale, red millet, arrowroot, cassava) described in preceding paper* are given. The bread and cake baking potential of cereal starches was adversely affected by the treatment. Although the quality of breads and cakes failed to match that of untreated wheat starch, the treatment improved tuber starches, suggesting that the molecular order of starches is an important factor in starch baking quality. Thickening properties tested with pie fillings demonstrated adverse effects of the treatment on this starch property.
Infrared and X‐Ray Analysis of Hydroxyethyl Starch
Authors: El‐Hinnawy S. I. , El‐Saied H. M. , Fahmy A. , El‐Shirbeeny A. E. , El‐Sahy K. M.
Published: November 2006

The effect ob substituted groups in hydroxyethyl starches with variable degrees of substitution on the conformation of starch molecules was investigated by the infrared and X‐ray analysis. The highest substitution with alkoxyl groups caused the shifting of the equatorial anomeric groups of glucose units to the axial position due to strain effect in the rings of monomers. The X‐ray analysis showed that the volume of unit cell of starch was increased 4.3% with the highest substitution of corn starch. This improved the penetration of dye molecules in the coating of textiles.
Viscosity and Gelatinization Characteristics of Hydroxyethyl Starch
Authors: El‐Hinnawy S. I. , El‐Saied H. M. , Fahmy A. , El‐Shirbeeny A. E. , El‐Sahy K. M.
Published: November 2006

Viscosity and gelatinization characteristics of corn and potato starches as well as their hydroxyethyl derivatives were investigated. The inherent viscosity increased from 164 in native corn starch to 209 in etherified one of DS 0.18. The etherified corn starch gelatinized at lower temperature than native corn starch due to their increase of DS. Maximum viscosity decreased from 93°C to 69°C for the modified corn starch. The retrogradation of starch was minimized by etherification as retrogradation ability of corn starch from its solution decrease from 22% to 6%. This is of great importance when starch is used as blood plasma volume expander. Variable results were obtained with etherified potato starch which might be due to its high contents of phosphorus.
Polystyrolgebundene Glucoamylase: Kinetisches Verhalten des Enzyms aus Endomycopsis bispora gegenüber technischen Substratlösungen
Authors: Fischer J. , Hettwer W. , Mansfeld H.‐W. , Wahl G. , Schellenberger A.
Published: November 2006

Glucoamylase aus Endomycopsis bispora wurde durch Glutar aldehyd kovalent an makroporöses Poly(ethylendiaminomethylstyrol) gebunden. Das Verhalten dieses Enzymderivates wurde im Rühr‐ und Kolonnenreaktor gegenüber säureverflüssigter Maisstärke (DE = 20,8%; DX = 4,5%)als Substrat kinetisch charakterisiert. Darüber hinaus wurden Reaktorgeometrie und Enzymharzmenge in der Reaktionssäule variiert und an Hand von experimentellen und berechneten Daten verschiedene Einflußgrößen bei der heterogenen Enzymreaktion diskutiert. Auf Grund der hohen spezifischen und relativen Aktivität und der günstigen mechanischen und hydrodynamischen Eigenschaften des Trägermaterials ist Polystyrol‐Glucoamylase für die technische Stärkeverzuckerung interessant.
Effect of Monoglyceride on Some Rehydrating Properties of Potato Granules
Authors: Hoover R. , Hadziyev D.
Published: November 2006

Monoglyceride incorporation in an Add‐Back (A – B) or Freeze‐Thaw (F – T) process decreases the potato granules Blue Value Index (BVI), Swelling Power (SP), rehydration rate and Water Binding Capacity (WBC), and increases the intact sound cell count. With 0.2% monoglyceride, SP, WBC and rehydration rate of A – B granules were 8.4, 6.7 and 6.4%, respectively, lower than F – T granules, while the BVI of A – B granules was 25.3% higher. Monoglyceride increase above 0.2% caused negligible changes. The intact sound cell count was higher when a precooking step was applied. The porous F – T and compact A – B granule structures partially accounted for differing water penetration rates. X‐ray analysis revealed a weak monoglyceride‐starch interaction during processing.
Preparation and Some Physicochemical Properties of Pyrodextrins of Ragi, Wheat, Jowar and Rice Starches
Authors: Wankhede D. B. , Umadevi S.
Published: November 2006

Ragi (Eleusine coracana), wheat (Triticum aestivum), jowar (Sorghum vulgare) and rice (Oryza sativa) starches (moisture content 8% ± 2%) were dextrinized in the absence of any added catalyst at 200°C ± 5°C. The changes in the physicochemical properties of dextrins during pyrodextrinization process were investigated. The results of the present investigation revealed that the progressive increase in the solubility, reducing power and alkali lability values while considerable decrease in β‐amylolysis limit and iodine affinity values of pyrodextrins could be correlated to the initial hydrolysis, increase in the degree of branching during transglycosidation and elaboration of thermal degraded products during the pyrodextrinization of starches.
Degradation of Dialdehyde Starch and Similar Dialdehydes with Sodium Sulfite. Part II. Simultaneous Conversion of Glyoxal Moiety into Tetrahydroxybenzoquinone
Authors: Abdel‐Akher M.
Published: November 2006

Degradation of dialdehyde starch with sodium sulfite gave rise to tetrahydroxybenzoquinone which was separated and characterized with its anilide derivative and its barium salt. The present views attribute the simultaneous conversion of the glyoxal moiety into tetrahydroxybenzoquinone to the formation of a transition intermediate containing bisulfite radical which under the alkaline conditions of the reaction gives rise to tetrahydroxybenzoquinone. This mechanism was confirmed by preparing monobisulfite dialdehyde starch which is degraded with sodium hydroxide giving rise to tetrahydroxybenzoquinone. All dialdehyde polysaccharides or glycosides tested and containing glyoxal moiety gave rise to tetrahydroxybenzoquinone while dialdehydes devoid of the glyoxal moiety such as inulin dialdehyde failed to give positive results.
Physical Properties of Starch from Cavendish Banana Fruit
Authors: Ling L.‐H. , Osman E. M. , Fernandes J. B. , Reilly P. J.
Published: November 2006

Starch was isolated from green Cavendish bananas after sodium hydroxide treatment, and its physical properties as they affected its potential acceptance as a food ingredient were measured and compared with those of corn, waxy corn, waxy corn diphosphate, acetylated waxy corn diphosphate, potato, and tapioca starches. Banana starch granules had a moisture content of 15.5%, an amylose content of 19.5% on a dry weight basis, and were highly irregular in shape and size, with the mode of characteristic length falling at 15 μm. The gelatinization range was 70.1 °C to 74.6 °C. Scanning electron micrography showed that in water the granules underwent surface cracking at 65 °C and progressively greater swelling, deformation, and erosion between 70 °C and 90 °C. At 95 °C, 6% banana starch paste in a Brabender Amylograph had a viscosity four times that of corn starch paste of the same concentration, and viscosity decreased rather slowly with stirring. The paste was somewhat longer than that of corn starch, but appreciably shorter than tapioca starch paste. Gelled banana starch was nearly as strong as corn starch, and also was nearly as opaque and reflective.
Processing of Cassava to Produce Ethanol – Effect of Raw Material Preparation
Authors: Greenfield P. F. , Lucia St. , Brooks R. B.
Published: November 2006

The effect of disintegration severity on starch hydrolysis and ethanol production from cassava roots and stems has been evaluated. It was found that a considerable fraction of the starch in the roots was made available for hydrolysis with relatively crude processing; all such material was readily fermented. To achieve a very high fermentables yield, either very intensive processing or, preferably, a two stage process, with the second stage being applied only to the oversize material, is required. Whether it is economically viable to process the oversize material further depends on a number of site‐specific factors. The two stage option appears the more attractive alternative especially in small to medium size cassava to ethanol plants because of the need to minimise power requirements and thereby steam usage.
Bestimmung des Gehaltes an Stärkekörnern gleichen spez. Gewichts und gleicher Größe
Authors: Wąchalewski T.
Published: November 2006

Verschiedene Methoden zur Bestimmung und Fraktionierung von Stärkekörnern verschiedener Größe und verschiedenen spez. Gewichts wurden untersucht. Am besten geeignet ist die Methode, bei der die Stärke mittels Zentrifuge in Fraktionen von bestimmten spez. Gewicht aufgetrennt wird. Die erhaltenen Fraktionen werden der kolorimetrischen Bestimmung des Gehaltes an Stärkekörnern verschiedener Größe unterzogen.
Starch Gelatinization: A Morphological Study of Triticeae and Other Starches
Authors: Williams M. R. , Bowler P.
Published: November 2006

Scanning electron microscopy has been used to study the swelling properties of potato, maize, rye, barley, field bean and oat starch in terms of morphological changes during heating in aqueous suspension. It is shown that starches from the endosperm of the Triticeae (wheat, barley and rye) studied here share a common mode of swelling which differs from the other starches examined.
Effects of Storage on Dynamic Rheological Properties of Wheat Starch Pastes
Authors: Wong R. B. K. , Lelievre J.
Published: November 2006

The variation of the dynamic rigidities of wheat starch pastes during storage at various temperatures has been measured. The results suggest that a crystallization process is responsible for the observed increase in dynamic rigidity with time. The Avrami equation was used to interpret the results in an attempt to establish the mechanism of crystallization.
Tentative Hypothesis to Explain How Electrolytes Affect the Gelatinization Temperature of Starches in Water
Authors: Oosten B. J.
Published: November 2006

An hypothesis is proposed to explain some phenomena arising from the interactions between starch and electrolytes in water. The basis of this hypothesis is formed by the following claims: a) starch is a weak acid ion exchanger; b) cations tend to protect and to stabilize the granule structure; c) anions are the gelatinizing agents by rupturing hydrogen bonds. Arguments are put forward to sustain these claims.
Effect of Chemical Treatments and Gamma Rays on Starch Content of Sweet Potatoes and Its Properties
Authors: Roushdi M. , Sarhan M. A. , Fahmy A. A.
Published: November 2006

The effect of soaking sweet potatoe slices in citric acid, sodium bisulphite and SO2 gas followed by drying, either in sun or in aerated oven, on starch content and its properties was investigated. The sweet potato tubers were also stored after irradiation with gamma rays. The starch was isolated and some of its poperties were studied. It was found that fuming with SO2, followed by sun drying and storing or irradiation of tubers at 5 krad gave very close results regarding yield of starch and its properties versus starch isolated from fresh tubers.
Rheological Properties of Concentrated Wheat Starch Gels
Authors: Eliasson A.‐C. , Bohlin L.
Published: November 2006

The rheological properties of concentrated wheat starch gels were measured with shear stress relaxation experiments in cone‐plate geometry. The water content of the investigated gels were 80, 60, 50 and 30% (w/w), respectively, and the relaxation modulus (G) and half relaxation time (T1/2) were studied after heating to different temperatures. For the gels with 50% and 60% (w/w) of water, a maximum value of G was obtained when the temperature interval for gelatinization was passed. When these gels were heated to higher temperatures, G decreased, and T1/2 increased, whereas gels with 30 and 80% (w/w) of water behaved differently. The influence of particle size distribution on the rheological properties of concentrated starch gels, was also investigated. It was found that G and T1/2 increased with a greater fraction of small starch granules.
Versuche zur Aufklärung der Struktur von Citratstärken. 1. Mitteilung. Spaltung der Esterbindung unter milden Reaktionsbedingungen
Authors: Klaushofer H. , Bleier J.
Published: November 2006

An einigen mittel‐ und hochveresterten Citratstärken (2,6 bis 3,75% esterartig gebundene Citronensäure) wurde das Ausmaß der Esterspaltung unter milden Reaktionsbedingungen (pH = 2,5 bzw. 4,4,8,0 und 8,5; Temperatur 40 bzw. 55 und 80 °C) untersucht. Im sauren Bereich werden in 100 h maximal 5% der esterartigen Bindungen gespalten. Im schwach alkalischen Bereich werden bei 40 °C ähnliche Werte gefunden, bei 80 °C und pH = 8.0 wurde jedoch innerhalb von 20 h der Citratester zu 80% verseift.
Purification and Characterization of a Thermophilic α‐Amylase of Aspergillus niger van Tieghem
Authors: Ramasesh N. , Sreekantiah K. R. , Murthy V. S.
Published: November 2006

The exocellular α‐amylase of a strain of Aspergillus niger van Tieghem (elaborating both dextrifying and saccharifying thermophilic amylases) was purified to homogeneity. Purification was achieved by providing cultural conditions for the organism to preferentially synthesize α‐amylase and fractionation of the culture filtrate by DEAE‐Sephadex chromatography. Its purity was established by gel electrophoresis and confirmed by sedimentation studies. The molecular weight of the enzyme was 56,230. Its Km values on different starches, temperature and pH optima for activity and energy of activation were established. Compared to literature values for other fungal α‐amylases, this enzyme exhibited a lower energy of activation, increased tolerance to lower pH and enhanced affinity to starch, highlighting its potential industrial application. While Ag+, Pb2+, Hg+, Al3+ and EDTA inhibited the activity of the enzyme, Ca2+ enhanced its activity, apart from conferring thermal stability and lowered activation energy. The product of its action on starch were maltooligosaccharides, maltose and glucose.
Herstellung von Gärungsethanol aus Nebenprodukten der Stärkeindustrie, insbesondere aus Kartoffelpülpe
Authors: Marihart J.
Published: November 2006

Es wird eine Anlage beschrieben, die in der Lage ist, Nebenprodukte höchst unterschiedlicher Qualität und ungleichmäßigen Anfalls aus Kartoffel‐ und Weizenstärkefabriken, Stärkederivatisierung, Stärkeverzuckerung und Kartoffelflockenerzeugung zu Ethanol zu verarbeiten.

Besonderes Interesse gilt dabei der Kartoffelpülpe, die mengenmäßig den größten Anteil darstellt und deren Absatz bisher als Futtermittel – gepreßt oder getrocknet ‐ bestenfalls gerade kostendeckend möglich ist oder im Falle der Trocknung erhebliche Kosten verursacht. Auf Grund der Zusammensetzung von Kartoffelpülpe – besonders durch den Gehalt an Quellstoffen wie Pektin und Hemicellulosen – ist eine Verwertung zu Ethylalkohol nach konventionellen Verfahren gleichfalls schwierig. Als Ergebnis diesbezüglicher einschlägiger Arbeiten wird ein Hydrolyse‐Verfahren auf Basis säure‐enzymatischer Methoden beschrieben, das insbesondere auf die Erzielung möglichst hoher Hydrolysattrockensubstanzen in Hinblick auf die Vergärung ausgerichtet ist.
Thermodynamics of Moist Grain
Authors: Lancaster E. B.
Published: November 2006

From thermodynamic theory, equations are developed for relating the heat of wetting of wheat flour to the relative humidity of air. For limited data on several grains and flours and for cotton fiber, the three pertinent parameters: ø, the thermodynamic potential; K, the equilibrium constant; and Ws, the saturation moisture content were determined. While K is remarkably uniform over all substances, ø varies with temperature and Ws with time and substance. The relative humidity relationship has the virtue of simplicity so that either relative humidity or moisture content can be calculated one from the other without difficulty once the parameters are known.
Recent Data on the Active Centre of Amylolytic Enzymes
Authors: Holló J. , Lászlo E. , Hoschke Á. , El Hawary F. , Bánky B.
Published: November 2006

The amount and configuration of products formed from starch are determined by the size, the structure and the functional groups of the active centre of amylolytic enzymes. In a previous publication we had determined the role of histidil and tyrosil side chains in the case of amylolytic enzymes. In this paper we have studied the role of tryptophyl‐, amino‐ and carboxyl groups. For this purpose the above groups have been modified by specific chemical reactions and the effect of modification on substrate binding and product formation has been determined for each enzyme.

Subsite maps of the individual enzymes were prepared on the basis of the probability of bond scission of 14C‐labelled maltodextrines. The effect of the modification of above functional groups on changes in the subsite maps has been determined. On the basis of the above, the individual functional groups could be located within the active centre. With knowledge and appropriate modification of the site of given functional groups the product spectrum of the individual α‐amylases could be changed. By this method, starch decomposition can be performed as required by practical demands.
Studies of Starch Size and Distribution in 33 Barley Varieties with a Celloscope
Authors: Mäkelä M. J. , Korpela T. , Laakso S.
Published: November 2006

Detailed starch particle distribution curves for 33 Finnish barley varieties were determined by a Celloscope technique. All of the curves showed two maxima with respect to both the number and mass. Reproducibility of the counting method was controlled by making duplicate samples to test critical points in the sample treatment. Amounts of the small granules in the barley varieties were rather similar, but average volumes of the large particles varied by even more than 100%. This showed that the essential differences between the varieties appeared in the region termed here as the medium size granules. Based on the knowledge of the accurate size distribution curves from 33 different barley varieties an easy and simple procedure was developed to evaluate granule size distributions of starch in barley samples well enough for practical purposes.
Equilibrium Reactions of Sugars During Chromatographic Analysis and Their Influence on Elution Time, Peakwidth and Molar Response in Modern Separation Systems
Authors: Verhaar L. A. T.
Published: November 2006

Solutes, especially sugars, can undergo several equilibrium reactions during liquid‐chromatographic elution like mutarotation, lactonization, isomerization, complexation and combinations of these. This can influence chromatographic parameters as: elution time, peak form and ‐width, and molar response.
Synthesis and Study of Polyacids from Soluble Starch and Chloroacetic Acids
Authors: Mofti A. , Hassan E. A. , Salama J. Y. , El‐Sabbah M. M. B.
Published: November 2006

The optimum conditions for the condensation of soluble starch with sodium salt of monochloroacetic acid in aqueous sodium hydroxide solution were determined. Condensation of soluble starch with sodium salts of di‐ and tri‐chloroacetic acids was carried out under the same optimum conditions. Higher values of yield, acid number, specific viscosity, and consequently degree of substitution are attained upon repeating the process of carboxylation. Apparent pK values were determined. The apparent strength which is lower than the corresponding chloroacetic acid, and the capacity derived from potentiometric titration curves, increase in presence of potassium chloride for all the three acids.
Hirse und Bruchreis als Basismaterial für die Glucosegewinnung
Authors: Tegge G. , Richter G.
Published: November 2006

Zwei stärkereiche Ausgangsprodukte, mexikanisches Hirsemehl und pakistanischer Bruchreis, wurden ohne vorherige Isolierung der Stärke zu verschiedenen Verzuckerungsprodukten verarbeitet. Die durch „direkte”︁ enzymatische Verzuckerung des Stärkeanteils erhaltenen dünnflüssigen Säfte wurden zu maltosereichem oder glucosereichem Sirup aufgearbeitet und letzterer auch der Isomerisierung mittels Glucoseisomerase unterzogen. Die verwendete immobilisierte Glucoseisomerase verlor sehr rasch ihre Aktivität und ließ sich auch durch Behandlung mit reiner Glucoselösung nicht wieder reaktivieren. Mit beiden Ausgangsmaterialien wurden Verzuckerungsprodukte mit geringerer Reinheit als bei gereinigten Stärken erhalten. Sowohl auf dem Lebensmittelsektor als auch in vielen technischen Bereichen stören die Begleitstoffe jedoch meistens gar nicht. Ist ihre Abtrennung trotzdem erforderlich, so ist dies in vielen Fällen bei der Weiterverarbeitung erst in einem späteren Stadium sinnvoll.
Activity and Activity Coefficient of Counter Monovalent Ions in Aqueous Polyelectrolyte Solutions from Carboxyalkylated Starch
Authors: Mofti A. , Hassan E. A. , Salama J. Y. , El‐Sabbah M. M. B.
Published: November 2006

Activity and activity coefficient were determined and compared for counter H+, Li+, Na+, K+ and Ag+ ions in polyelectrolyte solutions prepared from the condensation products of starch and sodium salts of mono‐, di‐, and trichloroacetic acids. Na‐glass electrode was used for measuring the activity of Na+ ions; Ag‐electrode for the measurement of the activity of Ag+ ions, and ion‐exchange permselective membrane were also used in concentration cells to determine the activities of H+, Na+, and K+ ions. For salt‐free polyelectrolyte solutions, the activity coefficient of each ion, at equal concentrations, increases in the above mentioned order of the polymer used. In all cases the activity coefficient increases in the following order of the studied monovalent cations: Ag+ < K+ < Na+ < Li+ < H+.
Preparation of Mixed Derivatives of Carboxymethyl Starch and Determination of Substitution Degree by a New Colorimetric Method
Authors: Roushdi M. , Abdel‐Akher M. , Ismail F. A. , Attia E.
Published: November 2006

Carboxymethyl starch (CMS) and mixed CMS‐benzoate derivatives were prepared and some physical properties were estimated. A new colorimetric method for determination of the substitution degree (D. S.) of CMS derivatives by using I‐acid was developed. The factors affecting the color development and stability of I‐acid method were studied and the most suitable conditions for color reaction were found. The substitution degrees of prepared CMS and its mixed derivatives were determined by the I‐acid method and the results were compared with those of classical methods.
Sulfur Containing Starches
Authors: Bączkowicz M. , Pałasiński M. , Tomasik P.
Published: November 2006

All the preparations, properties and applications are presented of starches which were chemically modified in order to introduce sulfur containing groups. Starch formulations bearing sulfur containing additives are also briefly discussed.
Vergleichende Untersuchung der Methoden zur Bestimmung der Aktivität bakterieller alpha‐Amylasen
Authors: Marciniak G. P. , Kula M.‐R.
Published: November 2006

Acht Methoden zur Bestimmung der bakteriellen α‐Amylaseaktivität wurden überprüft, und es wurde versucht, Umrechnungsfaktoren der verschiedenen Aktivitätseinheiten zu ermitteln. Der Phadebas‐Amylase‐Test hat sich dabei im Hinblick auf die gewünschte Empfindlichkeit, den geringen Arbeitsaufwand und die Anwendbarkeit zur Bestimmung der α‐Amylase in Gegenwart von Pullulanase und Glucoamylase als gut geeignet erwiesen. Die höchste Genauigkeit der Bestimmung sichern die amyloklastischen Methoden. Bemerkenswert ist es, daß die Anwesenheit von Pullulanase die dextrinogene Wirkung der α‐Amylase mindert. Die Methoden, die auf quantitativer Erfassung der reduzierenden Gruppen beruhen, sowie eine in den Vergleich einbezogene viskosimetrische Methode sind vergleichsweise weniger spezifisch und weniger genau.
Prinzipien der Dampf‐Kraft‐Koppelung am Beispiel der Stärke‐Herstellung
Authors: Hemmersbach K.
Published: November 2006

Die Kraft‐Wärme‐Kopplung ermöglicht eine ökonomische und umweltfreundliche Verwendung der Primär‐Energien mit Ausnutzungsgraden von 80–90% gegenüber 30–40% bei der separaten Strom‐Erzeugung. Anlagen zur Kraft‐Wärme‐Kopplung werden wegen der Einsparung an Primär‐Energie in vielen Ländern durch staatliche Investitions‐Beihilfen gefördert.

In der Stärke‐Industrie bietet sich von der Struktur des Bedarfs an Kraft und Wärme her die Anwendung der Kraft‐Wärme‐Kopplung an. Die Einsparung an Primär‐Energie durch die Kraft‐Wärme‐Kopplung ist eine Möglichkeit, langfristig durch eine einmalige Investition die Produktionskosten zu senken.

Die Technologie der Kraft‐Wärme‐Kopplung ist seit langem bekannt. Es stehen eine Vielzahl von Alternativen zur Verfügung, die im konkreten Einzelfall unter Berücksichtigung verschiedener begrenzender Faktoren den jeweiligen Erfordernissen anzupassen sind. Eine Weiterentwicklung der Technologien im Hinblick auf bessere Brennstoff‐Ausnutzung, mehr Umweltfreundlichkeit, Nutzung von ballastreicheren Brennstoffen ist weltweit zu beobachten.
The Starch of Pueraria tuberosa — Comparison with Maize Starch
Authors: Soni P. L. , Agarwal A.
Published: November 2006

Pueraria tuberosa starch was isolated from the tuber and purified. Scanning electron microscopy of the starch showed polygonal shaped granules which were almost of the same particle size as those of maize starch. P. tuberosa starch has lower amylose content, almost same gelatinization temperature range and water binding capacity, more swelling and solubility compared to maize starch. Paste viscosity characteristics show high peak viscosity but also indicate fragile nature of granules in comparison to maize starch.
Effect of Dehydration Methods on the Functionality of Plant Protein Concentrates
Authors: Knorr D. , Betschart A. A.
Published: November 2006

The significance of different dehydration methods for rice bran protein and soy protein coagulates on composition and functionality of the resulting protein concentrates was investigated. Minor compositional differences were found between the freeze‐, spray‐ or drum‐dried samples. Protein solubility data indicated limited effects of dehydration methods on heat coagulated samples but significant reduction of protein solubility by drum drying was found in the case of soy protein coagulated at room temperature. Water absorption capacity and emulsion properties were significant affected by dehydration methods but no consistent trends could be observed for fat absorption capacity. A significant increase of specific bread loaf volume, relaxation time of doughs and in some cases deformation of protein fortified samples was detected from freeze‐dried to drum‐dried samples. In general the effects of dehydration methods on protein functionality were more consistent for heat coagulated rice bran protein than for soy protein concentrates processed at ambient temperatures.
Buffalo Gourd Root Starch. Part I. Properties and Structure
Authors: Dreher M. L. , Berry J. W.
Published: November 2006

The structural and physico‐chemical properties of starch isolated from three genetically different populations of buffalo gourd (Cucurbita foetidissima HBK) were explored. The proximate composition of this starch was found to be similar to that of other starches. Granules were depicted to vary in shape (round, oval, truncated) and to resemble maize starch in size. A change in X‐ray diffraction behavior from a B‐ to a C‐type pattern was observed upon autoclaving raw gourd starch. Average physico‐chemical values were reported as follows: amylose content, 23.1%; water binding capacity, 112; and gelatinization temperature range, 61–69°C. Variation in alkali numbers among samples of this starch was extensive. A highly ordered internal structure of the granule was suggested by low values of swelling power and solubility and high initial pasting temperatures. Pasting curves of buffalo gourd starches were developed which revealed stable gel viscosities throughout the temperature cycle. Amylose fractions were found to be resistant to β‐amylase attack and exhibited an average DPη of 1915. Amylopectins were shown to have an average DPη of 2000, and an OCL to ICL of 1.3 to 1.
Yield Stresses in Cooked Wheat Starch Dispersions
Authors: Bagley E. B. , Christianson D. D.
Published: November 2006

Wheat starch dispersions of 8–15% concentrations were cooked in the temperature range 60°–75°C for periods up to 75 min. Viscosities of the cooked dispersions were determined in a rotational viscometer at 60°C and 23°C. No yield points were observed in the viscosity behavior at 60°C. At 23°C, viscosity measurements showed yield points in the range 200–3.000 dynes/cm2 dependent on cook time, cook temperature, concentration and cooling history. Plots of log viscosity versus log shear stress were useful in establishing the existence of yield points where the usual plots of shear rate versus shear stress were ambiguous.
Starch Hydrolysates with Very Low Degrees of Polydispersity
Authors: Çőrüşlü E. , Pekin B.
Published: November 2006

Acidic hydrolysis of starch, in contrast to enzymatic hydrolysis, gives a very low degree of multiple attack. By making use of this property it seems possible to prepare polysaccharide mixtures with very narrow ranges of molecular weight distribution. In a commercial sample of soluble starch the ratio of weight to number average molecular weights (M̄w/M̄n), which is a direct measure of polydispersity, is decreased from 3.1 to 1.2 by acid hydrolysis followed by ethanol‐water precipitation.
Physico‐chemical Characteristics of Starches from Chick Pea, Cow Pea and Horse Gram
Authors: Faki H. A. El , Desikachar H. S. R. , Paramahans S. V. , Tharanathan R. N.
Published: November 2006

Starches were isolated in 36, 37 and 28% yields, from chick pea, cow pea and horse gram, respectively. Study of their properties revealed mixed granule population; single stage swelling with high solubility in water for cow pea and horse gram starches in comparison to chick pea starch; slightly higher solubility in DMSO for chick pea starch followed by cow pea and horse gram starches; a relatively high viscosity in alkaline solution of cow pea starch; and Brabender amylograms indicating a low slurry viscosity and low set back in the case of chick pea starch compared to the other two starches which exhibited considerable peak viscosity as well as retrogradation. All the starches contained amylose in the range of 32 – 34%. X‐ray powder patterns showed chick pea and horse gram starches to be of B‐type, whereas cow pea starch was of A‐type.
Zwei Sorten von Stärkekörnern in reifen Maiskörnern?
Authors: Czaja A. Th.
Published: November 2006

Maiskörner im unreifen Kolben enthalten zunächst nur einheitliche Stärkekörner wie das Hornendosperm des reifen Kornes. Unter dem Einfluß des sich entwickelnden Scutellums mit dem Embryo werden bei der Nachreife der Körner die Stärkekörner in der nächsten Umgebung dieser fermentativ abgebaut. Auf diese Weise entsteht im Inneren der Maiskörner das sogenannte Mehlendosperm als optisch inaktiver Restkörper.
Carbohydrate Make‐up of Chick Pea, Cow Pea and Horse Gram
Authors: Faki H. A. El , Desikachar H. S. R. , Paramahans S. V. , Tharanathan R. N.
Published: November 2006

Extraction with 70% ethanol of chick pea, cow pea and horse gram yielded 7.1, 8.1 and 3.6%, respectively of free sugars, all showing the presence of galactose, glucose, sucrose, raffinose, stachyose and verbascose in varying proportions. Starch was isolated in 28 – 37% yields; whereas the unavailable carbohydrates were found to be 17.6, 14.5 and 24.2% respectively. All the fractions contained uronic acid, pentoses and hexoses in different proportions. No ethanol‐soluble sugar or starch was detectable in the husk. The husk was rich in cellulose which still contained small amounts of pentose constituents, indicating probably its incomplete extraction or a strong macromolecular association.
Explanations for Phenomena Arising from Starch‐Electrolytes Interactions
Authors: Oosten B. J.
Published: November 2006

In a previous contribution a hypothesis has been proposed to explain the substantial rise of the gelatinization temperature resulting from the addition of sodiumhydroxide to a salty starch suspension. Other phenomena arising from the interactions between starch and electrolytes as reversible swelling of starch, stable starch suspensions in concentrated solutions of electrolytes, influence of acids and changes in heats of adsorption and desorption can be explained by the same hypothesis. This contribution is devoted to explain these phenomena.