bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Processing on the Physico‐Chemical Characteristics of Quinoa Flour (Chenopodium quinoa, Willd)
Authors: Ruales Jenny , Valencia Silvia , Nair Baboo 
Published: November 2006

AbstractThe nature and extent of the modification of starch in quinoa, caused by various processes like cooking and autoclaving of the seeds, drum drying of the flour and extrusion of the grits was investigated by measuring the physico‐chemical properties ‐ the water absorption, water solubility, swelling power, viscosity and degree of gelatinisation ‐ of the processed samples. Autoclaved samples showed the lowest degree of gelatinisation (32.5% by DSC) of the starch, while the degree of gelatinisation of the precooked/drum dried samples was found to be 97.4% by DSC method. Higher polymer degradation was observed in cooked samples than in autoclaved samples as seen in the gel chromatographic separation. The water solubility in cooked samples (5.44 to 15.58) and in autoclaved samples (7.02 to 9.64) increased with the process time. In the extrusion process, the moisture content as well as the compression ratio was found to affect the degree of starch modification significantly (p <0.01).
Studies on Modification of Enzymatic Saccharification Process
Authors: Slomińska Lucyna 
Published: November 2006

AbstractIn general the production of high DE starch hydrolysates in a sequence of continous process steps (liquefacion) and discontinuous steps (bath saccharification). The batchwise saccharification process requires long conversion time (48–72 h) what is connected with the necessity to operate large saccharification tank volumes. Attemps to change saccharification conditions for reduction in significant degree of enzymatic time degradation of liquefied starch combined with increasing substrate conversion have been made.
A Simple Laboratory Scale Method for Isolation of Amaranth Starch
Authors: Perez E. , Bahnassey Y. A. , Breene W. M. 
Published: November 2006

AbstractStarch was isolated from the seeds of Amaranthus hypochondriacus and Amaranthus cruentus by two established methods and a new simpler method involving steeping in dilute alkali, neutralization, and ambient air drying without using expensive or highly hazardous chemicals. The latter is recommended for isolating amaranth starch for human food uses on a laboratory scale.
Some Chemical, Physical, and Functional Properties of Native and Modified Starches of Amaranthus hypochondriacus and Amaranthus cruentus
Authors: Perez E. , Bahnassey Y. A. , Breene W. M. 
Published: November 2006

AbstractStarch isolated from A. hypochondriacus and A. cruentus was chemically modified by cross‐linking with phosphate. Native and modified starches from both species did not differ in crude protein or fat content and overall purity and contained about 90% amylopectin and 10% amylose. Phosphorus and ash contents were highly correlated (r = 0.98). Modification eliminated swelling power at 85°C and increased gelatinization temperature range, gel consistency, and peak and overall consistencies while decreasing resistence to mechanical breakdown, blue value and initial pasting temperature. Modification effects were greater for A. hypochondriacus than for A. cruentus starch. Acidification to pH 4.5 decreased overall viscosity more in modified than in native forms.
Synergistic Action of α‐Amylase and Glucoamylase on Raw Corn
Authors: Arasaratnam Vasanthi , Balasubramaniam Kandiah 
Published: November 2006

AbstractOptimum ratio of glucoamylase to α‐amylase for synergistic hydrolysis of starch in corn flour was 1.8 AGU/1.0 KNU. The rate of hydrolysis of starch in dry milled corn was faster than that of waxy maize starch and wet processed corn. Hydrolysis of the starch in dry milled corn was the most efficient compared with that of wet milled, corn steeped in water or NaOH.
Annealing of Granular Rice Starches — Interpretation of the Effect on Phase Transitions Associated with Gelatinization
Authors: Seow C. C. , Teo C. H. 
Published: November 2006

AbstractThe effects of annealing on phase transitions associated with gelatinization at different moisture contents of an atypical non‐waxy rice starch exhibiting a clearer‐than‐usual glass transition were studied by differential scanning calorimetry. Consistent with observations on synthetic glassy polymers, annealing at temperatures below the glass transition for limited periods caused an elevation of Tg which is attributed to the slow relaxation of the amorphous regions of the starch granules to their equilibrium glassy states. The crystalline regions were significantly affected only after annealing at temperatures above the glass transition, the resulting increase in crystallite melting temperatures and narrowing of the gelatinization range being ascribed to crystal growth and/or perfection. Passage through the glass transition (which precedes crystallite melting) appears to give rise to an apparent endotherm which becomes even more prominent on sub‐Tg annealing of samples at low moisture contents. Annealing of an ordinary rice starch (with no clearly discernible glass transition) at a temperature below its onset gelatinization temperature (T0) produced effects which paralleled those observed after sub‐Tg annealing of the atypical rice starch. The conclusion drawn is that a glass transition is superposed on the crystalline melt at the leading edge of the single endothermic peak observed at high moisture contents. Where biphasic endotherms at intermediate moisture levels are concerned, however, the present results suggest that the first or G endotherm very likely arises from a glassy‐to‐rubbery state transformation while the second or M1 endotherm is associated with crystallite melting.
Physicochemical Properties of Defatted Oat Starch
Authors: Gibiński M. , Palasiński M. , Tomasik P. 
Published: November 2006

AbstractThree Polish varieties of oat starch were subjected to defatting by a cold extraction with the chloroform‐methanol‐water (3:2:1) mixture followed by a hot extraction with 1‐propanol. A comparison of results allowed discussion of the effectiveness of the extraction procedures, their effect on the structure of original starch as well as the structure of oat starch‐lipid inclusion complexes.
Effects of Shrunken and Other Mutations on the Properties of Rice Endosperm Starch
Authors: Asaoka Masako , Okuno Kazutoshi , Yano Masahiro , Fuwa Hidetsugu 
Published: November 2006

AbstractStarch granules were isolated from rice endosperms of twenty mutants, included two kinds of shrunken (shr) mutant, and two cultivars of their normal counterparts. The shr mutants, EM‐20 and Kenkei 2088, showed opposite effects on the amylose content, that is, EM‐20 had 5% higher than its normal counterpart and Kenkei 2088 had 3% lower than its one. The amylopectin of EM‐20 was composed of slightly shorter chains on the average than its normal one. The gelatinization temperature and heat of gelatinization were affected by the mutation of shr, EM‐20. The amylose extender (ae) mutant, Kenkei 2064, had a comparable amylose content with its normal counterpart but its amylopectin had higher content of long chain than the normal one. Twelve kinds of dull (du) mutant reduced the amylose content which varied from 2% to 16%.
Molecular Properties of Cereal Based Breakfast Foods
Authors: Tan Yen , Chinnaswamy Rangan 
Published: November 2006

AbstractMolecular status of starch in ready‐to‐eat breakfast cereal foods and its relationship with cereal produkt functional properties such as water solubility index and water absorption index were studied. Gel chromatographic separation of cereal product polymers dispersed in DMSO gave three major fractions. Factions I and II reflected starch content, whereas Fraction III reflected the sugar content in the product formulation. Contents of Fraction I, II and III varied from 0.31 to 3.53 mg, 0.06 to 2.82 mg, and O to 4.63 mg, respectively. Water absorption index increased while water solubility index decreased with increasing Fraction I or Fraction II contents. Conversely, water absorption index decreased whereas water solubility index increased with increasing Fraction III content. Iodine blue values showed that Fraction I and Fraction II mainly composed of amylopectin and amylose, respectively. λmax values of Fraction I and II varied from 511 to 584 nm, 490 to 661 nm, respectively. Iodine binding capacity which was indicative of the amount of amylose present, varied from 0.37% (Kellogg's Corn Flakes) to 2.84% (Kellogg's Honey Smacks).
Structural Studies of Pullulan by Nuclear Magnetic Resonance Spectroscopy
Authors: McLntyre Deane D. , Calgary Hans J. Vogel 
Published: November 2006

AbstractNuclear Magnetic Resonance (NMR) spectroscopy was used to probe the primary structure of the glucan pullulan. Carbon‐13, proton and phosphorus‐31 NMR spectra in aqueous solution of the intact poly‐saccharide obtained from three different sources indicate that significant structural differences can occur among these samples. In particular, two samples consist solely of α(1 → 6) linked maltotriose units, in accord with the generally accepted structure. However a third sample has fewer α(1 → 6) linkages and appears to consist of higher α(1 → 6) linked maltooligosaccharides in addition to maltotriose. Unlike the other samples, this sample was also phosphorylated. Enzymatic digestion of pullulan followed by NMR spectroscopy using pullulanase confirmed these results, as did HPLC analysis of the resulting digest, which showed the presence of maltooligosaccharides consisting of ten and more glucose units. However, HPLC analysis of acid hydrolysed pullulan indicated that no sugars other than glucose were present in any of the samples examined.
Changes of Carbohydrate Compositions During Enzymatic Hydrolysis of Starches of Various Origin
Authors: Nebesny E. 
Published: November 2006

AbstractHydrolysis of starch of various origin, liquefied with bacterial α‐amylase to DE 13.5 and then saccharified only with glucoamylase and simultaneously with pullulanase to DE 97–98, was investigated. It was found that the hydrolysis of wheat starch was delayed in relation to the hydrolysis of potato and maize starch, particularly in the first period of saccharification. The delay decreased with time but at the end of the saccharification it was still 24 h. The carbohydrate composition of wheat starch hydrolyzates differed from the hydrolyzates of potato‐ and maize starch in a smaller content of glucose and lower oligosaccharides (G1‐G4) and a greater content of higher oligosaccharides and dextrins (G5‐Gn). This, among other things, could have an influence on higher viscosity of solutions of wheat starch hydrolyzates in relation to respective hydrolyzates of potato and maize starch.
Thermal Hysteresis of Infrared Spectra of Corn Starch/Water Systems
Authors: Mizoguchi Masaru 
Published: November 2006

AbstractInfrared spectra of O.10mm thick corn starch‐water systems were measured with a FTIR spectrometer. With increasing temperature from 25 to 95°C, the absorbance at 2700cm−1 decreased abruptly around 80°C due to sol‐gel process. The absorbance of the gel increased by freezing and returned to the unfrozen value after thawing. The present method of using the absorbance at 2700cm−1 is promising to investigate the interaction between water and starch including sol‐gel process.
Influence of Surfactants on the Rheological Behavior of Starch/Gelatin Gels and Gel‐Emulsions
Authors: Daković Ljubomir , Milošević Svetlana , Sovilj Verica 
Published: November 2006

AbstractThixotropic behavior of mixed 8% starch/gelatin gels and gel‐emulsions (8% of the sunflower oil dispersed in the starch/gelatin gel), prepared with the addition of different emulsifiers, by means of the rotational viscometer with coaxial cylinders, has been investigated. Different emulsifiers (Na‐dodecyl sulfate, cetyl alcohol, mono‐ and diglycerides of fatty acids and alkyl polyglycolethers) were applied before (at 40°C) and after (at 96°C) gelatinization of the starch. Thixotropic properties, i.e. the coefficients of thixotropy of gels and emulsions were determined by the thixotropic loop method. Samples were taken in different time intervals (up to 72 h), in order to investigate the ageing effects. Very stable gels and gel emulsions (containing carbohydrate, protein and fatty component), with high aging stability can be obtained.
Enzymatic Starch Hydrolysis of Extruded Potato Peels
Authors: Camire Mary Ellen , Camire Alex L. 
Published: November 2006

AbstractPotato peels discarded by potato processors are a potential source of dietary fiber and starch. This starch may be hydrolyzed for fermentation to value‐added products. Dried steam peels were extruded at 135°C and 22% feed moisture and digested with α‐amylase and/or amyloglucosidase. Two barrel temperatures and feed moistures were also studied. Glucose was measured colorimetrically at O,1,2,4,8 and 24h of incubation. All peels treated with either no enzymes or α‐amylase alone produced minimal glucose. Nonextruded peels digested with both enzymes produced more glucose than did those treated with amyloglucosidase alone. Complete digestion of starch occurred in extruded peels digested with amyloglucosidase, but not when α‐amylase was used.
Some Studies on Starch Carbamate
Authors: Khalil M. I. , Farag S. , Mostafa Kh. M. , Hebeish A. 
Published: November 2006

AbstractStarch carbamate was prepared by reacting maize starch with urea using solid state technique. The different factors affecting this reaction were studied. These factors include urea concentration, type of starch, reaction and duration. The carbamate extent and carbamation reaction efficiency (%) were traced by estimating the nitrogen content of the reaction product. Solubility, viscosity and total ester content of starch carbamate samples were estimated. The carbamate extent increases by increasing urea concentration as well as reaction temperature and duration. Increasing the reaction temperature and duration has the same effect on carbamation reaction efficiency (%), while increasing urea concentration do the reverse. The solubility (%) of starch carbamate samples depends on urea concentration, reaction temperature and duration as well as the type of starch used. The maximum solubility obtained was 63% and 43% for starch carbamate derived from pregelled and native starch, respectively. Tentative mechanism for the reaction between starch and urea has been proposed.
Conformational Contributions of Amylose and Amylopectin to the Structural Properties of Starches from Various Sources
Authors: Aberle Th. , Burchard W. , Vorwerg W. , Radosta S. 
Published: November 2006

AbstractSix starches of different amylose content were studied by static light scattering from very dilute aqueous solutions at 20°C. Reproducible results were obtained after submitting the solutions to a controlled autoclaving step where the solutions were heated up to 135‐155°C. Amylose rich starches exhibited significantly different angular dependences from those with low amylose content. The high experimental accuracy of the angular dependences allowed separate determination of the molar masses Mw and radii of gyration Rg for both components in the mixture. Molar masses of 60‐106 to 110‐ 106 and radii around 220nm were found for the amylopectins from the various starches. Unexpectedly high molar masses between 450‐103 and 2.5‐106 were found for the amylose components but only low radii of gyration. Comparison with synthetic amyloses indicate strong intra and intermolecular aggregation in the form of laterally (side‐by‐side) aligned chains which could contain up to 35 amylose chains. The possibility of a quantitative determination of the degree of branching via the shrinking factor g (=Rg2Ap/Rg2Am I at the same molar mass) is discussed at some length.
A Study of Starch Granular Aggregation
Authors: Wang Shaw S. , Qu Di , Chiew Yee C. 
Published: November 2006

AbstractThe aggregation behavior of starch granules during cooking was investigated. Granular aggregation was found to depend mainly on water content and degree of conversion (cooking) of starch. There were threshold values of water content and degree of conversion for powdery starch to undergo a phase transition from a nonaggregated to an aggregated state. A method for determining such threshold values of the transition was developed. A mathematical model was also developed to describe the aggregation behavior of cooked starch. Its potential application to food systems, especially to the simulation of starch extrusion process, was discussed.
Thermal Behaviour of Calcium‐Hydroxypropyl Rice Starch Complexes
Authors: Islam M. Nurul , Azemi B. M. N. Mohd. 
Published: November 2006

AbstractThermal behaviour of hydroxypropyl rice starches and their calcium complexes was determined by using Differential Scanning Calorimetry (DSC) with starch: water in the ratio of 1:1. Glass transition and gelatinization temperatures were reduced by hydroxypropyl groups and enhanced by calcium treatment. Gelatinization enthalpies were reduced by both hydroxypropyl groups and calcium treatment. The interaction of hydroxypropyl groups and calcium with starch altered the two endothermic peaks observed in native starch into a single melting peak.
Spectrophotometric Titration of Starch Polysaccharides with Iodine
Authors: Richter Manfred 
Published: November 2006

AbstractTwo methods of Spectrophotometric titration (SPT) are described. Method A describes the determination of the extinction (E) at 4 wavelengths (WL) 714, 625, 555, and 500 nm and of 16 concentrations of iodine in the range of [I] = 2.5 and 166.7 · 10−5 N I2 or pI = 4.60 and 2.28 (pI = ‐log [I]) as well as the calculation of the extinction‐relationship R of two WL for 6 possible pair combinations. The dependence of E respectively of log [I] in form of E‐ or R‐curves of amyloses, amylopectins, Nägeli‐amylodextrin and starches of several botanical sources are discussed under the aspect of the reaction of helical segments of molecules with iodine. Method B of the SPT defines E of the 4 wavelengths at pI 3.6 and 3.0 and calculation of the extinction relation ships R(M) and R(H) of middle (M) and high (H) concentrations of iodine. The position of the parameters R(M) and D=R(M) — R(H) of the 6 wavelength combinations in each X‐Y‐diagram depends on the botanical origin of potato, tapioca, wheat and regular maize starch.
Chemical Modification of Guaran Gum. Part 3: Carboxymethylation in non‐Aqueous Medium
Authors: Ragheb A. A. , Kamel M. , El‐Thalouth I. Abd , Nassar S. H. 
Published: November 2006

AbstractGuar gum was isolated from the seeds and subjected to modification via non‐aqueous carboxymethylation. Highly substituted carboxymethyl guaran derivatives could be obtained via repeating the reaction four times, where a product of degree of substitution (D.S.) 2.07 was obtained indicating that the free hydroxyl groups of both glucose and mannose (which form the main constituents of guaran) can react with monochloro acetic acid. The modification increases the solubility of the gum in cold water, and increases the stability of its pastes to microorganisms. Pastes of these derivatives are characterized by non‐Newtonian pseudoplastic behaviour regardless of their D.S. or the measuring temperature, while their apparent viscosity decreases by increasing the D.S. and/or the measuring temperature.
Microscopic Observation and X‐Ray Diffractometry of Heat/Moisture‐Treated Starch Granules
Authors: Kawabata Akiko , Takase Naoaki , Miyoshi Emako , Sawayama Shigeru , Kimura Toshiaki , Kudo Kenichi 
Published: November 2006

AbstractHeat/moisture‐treated potato and corn starch granules were observed by microscopy and X‐ray diffraction patterns were obtained. A scanning electron microscope (SEM) photograph of the cross section of the heat/moisture‐treated potato and corn starch granules showed a large hollow area about 1/3 of the diameter at the center of the starch granules and a layered structure resembling growth rings. From the X‐ray diagrams it was confirmed that heat/moisture‐treatment caused an alteration from the B‐type in the direction an A‐type structure in potato, whereas corn starch did not change and maintained an A‐type structure. The enzymatic digestibility of heat/moisture‐treated starch was found to be less resistant than that of native starch.
The Significance of Starch Polymorphism in Commercially Produced Parboiled Rice
Authors: Ong Mei H. , Blanshard John M. V. 
Published: November 2006

AbstractA study of eight commercial parboiled samples derived from two varieties of rice produced by four different processes has shown that depending on the parboiling process, the starch component itself can be present as native and/or retrograded starch in addition to the amylose‐lipid complex. Further, it was demonstrated that the polymorphic states of starch can influence the texture and behaviour of cooked rice. The parboiled rice samples which had all three states of starch (i.e. ungelatinized and recrystallized amylopectin plus the amylose‐lipid complex) possessed the hardest eating property but the lowest solubility. A negative linear relationship was demonstrated between the hardness and the solubility of cooked, parboiled rice. Overall, the observations suggest the existence of different forms of starch in parboiled rice which vary with the different parboiling protocols. The conditions governing their formation need to be established before investigating the specific functionality of individual forms within the rice. This study further confirmed that retrograded starch (amylopectin) in parboiled rice did not exhibit a B‐tye X‐ray pattern but mixed A+V patterns.
Utilization of Potato Pulp for Baking of Bread
Authors: Nebesny E. 
Published: November 2006

AbstractAqueous potato pulp suspension of 5% d.s. was subjected to streaming under pressure of 1 atmosphere for 1h and, subsequently, bounded starch was enzymatically liquefied and saccharified, insoluble suspension was filtered and rest of sugars was washed out with hot water and dried to obtain a fiber preparation containing 79% d.s. of dietary fiber. The fiber preparation produced from raw pulp contained only 71.7% d.s. of dietary fiber. For baking of bread wheat meal containing 0,5% and 10% of the fiber preparation obtained from potato pulp was used. Organoleptic tests and physico‐chemical properties of wheat bread containing 5% fiber preparation in relation to wheat meal, appeared to be as good as in bread without this preparation. However, bread containing the fiber preparation was healthier for consumers.
Verwendung von Kartoffelpülpe und Kartoffelfruchtwasser als Nährmedium zur Anzucht von Laccase produzierenden Pilzen
Authors: Trojanowski Jerzy , Kharazipour Alireza , Mayer Frank , Hüttermann Aloys 
Published: November 2006

AbstractAbfallprodukte aus der Stärkeindustrie (Kartoffelpülpe und Kartoffelfruchtwasser) werden als Nährlösung zur Anzucht von ausgewählten Polyporaceae‐Stämmen verwendet, aus denen phenoloxidierende Enzyme (Laccase) gewonnen werden können. In den von uns isolierten Stämmen von Trametes villosa, Trametes versicolor und Polyporus brumalis wurde neben einer hohen Laccase‐Aktivität zum ersten Mal auch eine hohe amylolytische Aktivität nachgewiesen. Die ausgewählten Stämme sind in der Lage, die stärkehaltige Pülpe als einzige C‐Quelle zu verwerten. In dem Kartoffelfruchtwasser wurden hohe Aminosäuren‐Gehalte, insbesondere Asparagin und Asparaginsäure gefunden, die eine optimale N‐Quelle für die verwendeten Weißfäulepilze darstellen. Technischer Einsatz der bei der Stärkegewinnung anfallenden Abfallprodukte zur Produktion von pilzlichen Enzymen bietet eine wirtschaftlich interessante Alternative zum kostspieligen synthetischen Standardmedium.