bluuebunny/crossref_metadata_2025_split huggingface dataset:
Functional properties of plant proteins Part 7. Rheological properties of succinylated protein isolates from faba beans (Vicia faba L.)
Authors: Prahl L. , Schwenke K. D. 
Published: November 2006

AbstractThe flow behaviour of unmodified and succinylated protein isolates from faba beans (FBPI) was studied in dependence on the degree of succinylation, temperature and protein concentration. The dispersions of exhaustively succinylated I‐BPI which represent unfolded proteins show structural viscosity and high yield values at room temperature and tend to jellify without heating. There exists a critical degree of succinylation (between 50 and 80%) at which the unfolding of the proteins begins. In the unmodified and moderately succinylated proteins this unfolding is characterized by a minimum of viscosity at a transition temperature and a sharp viscosity increase by further heating in the cyclic heating‐cooling diagram. The “transition” temperature of unmodified FBPI is identical with the “critical” temperature of aggregation in dilute solution. Flow curves of 10% dispersions of FBPI show a decrease of shear stress t with increasing succinylation up to a moderate degree of modification. The 49% succinylated sample shows the lowest value of t and nearly Newtonian fluid behaviour.
Stichprobenverfahren bei Rohfleisch
Authors: Schöberl E. , Körmendy L. , Erdös Z. 
Published: November 2006

AbstractDie Regelung der Zusammensetzung von Fleischprodukten erfolgt aufgrund der Kenntnis der chemischen Zusammensetzung der Rohstoffe, die deshalb möglichst genau bekannt sein muß. Da die für die Rohstoffzusammensetzung charakteristische Standardabweichung stark von den verwendeten Stichprobenverfahren abhängig ist, war unser Ziel die Ausarbeitung eines Verfahrens, das auf mathematisch‐statistischer Grundlage eine Anleitung zur entsprechenden Stichprobenentnahme unter Betriebsverhältnissen gibt. Die Standardabweichung ist vom Umfang der Stichprobe abhängig, während die zur gegebenen Standardabweichung gehörende Stichprobenmasse durch den Zerkleinerungsgrad und den Fettgehalt des Fleisches beeinflußt wird. Deshalb wurde in unseren Versuchen der Fettgehalt von durch Scheiben verschiedener Lochweite im Fleischwolf zerkleinerten Schweine‐ und Rindfleischproben bestimmt; die Ergebnisse wurden mit mathematisch‐statistischen Methoden ausgewertet, und es wurde eine Stichprobenverfahren‐Tabelle zusammengestellt. In ihr sind die zu den von uns festgesetzten Standardabweichungen gehörenden benötigten Stichprobenmassen bei drei verschiedenen Fettgehalten in Abhängigkeit von Scheiben verschiedener Lochdurchmesser angeführt.Bei Schweine‐ und Rindfleisch verschiedenen Zerkleinerungsgrades wurde auch eine Teilchenzählung vorgenommen; denn anhand der Teilchenmasse kann das Zerkleinern besser charakterisiert werden, als durch die Angabe der nominalen Lochweite der Scheibe allein.
Evaluation of protein mixtures in adults on the basis of scoring pattern deduced from Kofrányi's results
Authors: Dvořák Z. , Knesel L. 
Published: November 2006

AbstractMinimum protein requirements for adult males found by KOFRÁNYI in testing protein mixtures were compared with amino acid scoring pattern in which total non‐essential amino acids were also included. For protein mixtures composed of different ratios of animal and plant proteins the least minimum of protein required corresponded to the maximum of the courses of chemical score when non‐essential amino acids, lysine, sulfur amino acids or tryptophan respectively were taken as limiting. Particular comparisons indicate that total nonessential amino acids ought to be included in amino acid scoring pattern.
Zur Wirkung von Phenylquecksilberacetat und Nitrat bei kombinierter Verabreichung an Ratten: Schilddrüse, Enzyme der Leber, morphologische Befunde an Gehirn und Nieren
Authors: Höring H. , Ellinger Ch. , Nagel M. , Páldy A. , Dési I. 
Published: November 2006

AbstractRats were exposed to nitrate (NO−3) in drinking water. to phenylmercuryacetate (PMA) by gavage and to NO−3 and PMA together during 4 different experiments. PMA impaired kidneys, NO−3 thyroid gland, and NO−3 and PMA together both organs. In the last case a synergistic effect on the thyroid gland was shown. The lowest effective concentration of NO−3 was 40 mg/l. It resulted in histomorphological changes of the thyroid epithel cells. That low effective dose of NO−3 and possible synergistic effects should give a further impulse to take into consideration not only a low iodide intake but also goitrogenic environmental chemicals when evaluating the endemic goitre prevalence.
Functional properties of plant proteins. Part 8. Effect of succinylation on some functional properties of the main globulin fraction from rapeseed (Brassica napus L.)
Authors: Nitecka Elzbieta , Schwenke K. D. 
Published: November 2006

AbstractThe changes of some functional properties ‐ solubility, emulsifying and foaming properties, heat‐induced aggregation ‐ of a native rapeseed globulin preparation after succinylation has been studied. In correspondence with the results obtained with the purified rapeseed 12 S globulin and other globulin preparations from plant seeds, a total blocking of the amino groups of the rapeseed globulin could not be attained. The highest degree of modification reached was 83%. The unmodified protein has high foam capacity and stability. Succinylation until 61% did not change these properties. The emulsifying activity and emulsion stability were slightly improved after a modification at a low or moderate level. The heat‐coagulation of the native protein is depressed by increasing succinylation.
Herstellung weitgehend polygalacturonasefreier Pektinesterasepräparate
Authors: Dongowski G. , Bock W. 
Published: November 2006

AbstractZur Herstellung hochmolekularer niederveresterter Pektine mit statistisch verteilten Carboxylgruppen und gutem Geliervermögen werden Pektinesterase (PE; EC 3. 1. 1. 11)‐Präparate benötigt, die möglichst keine Pektindepolymeraseaktivitäten vom Endo‐Typ, insbesondere der Polygalacturonasen (PG; EC 3. 2. 1. 15), enthalten dürfen. Gereinigte PE‐Präparate aus verschiedenen Schimmelpilzen besitzen diese gewünschten Eigenschaften [1–4]. Handelsübliche Pektinasepräparate aus Schimmelpilzen sind jedoch stets Gemische pektinspaltender Enzyme und können außerdem eine Reihe von Begleitenzymen (Cellulasen, Hemicellulasen, Amylasen) enthalten. Chromatographische und elektrophoretische Laborverfahren liefern nur kleine Mengen gereinigter PE‐Präparate. Zur weitgehenden Inaktivierung bzw. Abtrennung der Pektindepolymerasen auf einfache Weise im vergrößerten Maßstab wurden mehrere Verfahren für eine Behandlung mikrobieller Pektinasen, z. B. nach einem speziellen Temperatur‐ und pH‐Wert‐Regime [5] bzw. mittels Tetrahydrofurfurylalkohol [6] oder Harnstoff und Thioharnstoff in wäßrigem Milieu [7], vorgeschlagen. Durch eine Harnstoffbehandlung, die u. a. eine Dissoziation von Proteinuntereinheiten bewirken kann [8], sollen auch amylolytische [9] und cellulolytische Enzympräparate [10] von pektinspaltenen Aktivitäten befreit werden können.Im folgenden wird über die weitgehende Inaktivierung der PG in handelsüblichen Pektinasepräparate durch Harnstoffbehandlung in alkoholisch‐wäßriger Lösung berichtet.
Mercury content in some fresh‐water fish from Alexandria
Authors: Moharram Y. G. , Moustafa E. K. , El‐Sokkary A. , Attia M. 
Published: November 2006

AbstractThe total‐Hg was determined and the distribution among the different organs of 3 fresh‐water fish caught from the lake Maruit at Alexandria was studied. Because one of these species (Mugil Cephalus) grows in both fresh and sea‐water the effect of growing medium was also investigated. It was found that the total‐Hg values differed according to species, size, and organs of fish as well as to fishing ground. It was also noticed that there was an interaction effect between the various factors on the accumulation of total‐Hg in fish. Generally, fish obtained from fresh water had lower levels of mercury compared with that collected from sea‐water.
Proteolytic activity of crude cell‐free extract of Lactobacillus casei and Lactobacillus plantarum
Authors: Hegazi F. Z. , Abo‐Elnaga I. G. 
Published: November 2006

AbstractCrude cell‐free extracts of some strains of each L. casei and L. plantarum were assayed for their amino‐, imino‐ and endopeptidase as well as the caseinolytic activity. L‐alanine‐, L‐phenylalanine‐ and L‐leucine‐p‐nitroanilide but not L‐glutamic acid‐p‐nitroanilide, were hydrolyzed by all the strains indicating an amino‐peptidase activity. The activity of proline iminopeptidase was very low compared to that of the aminopeptidase. L. casei could be distinguished from L. plantarum by its high endopeptidase activity against succinyl‐phenylalanine‐ and glutaryl‐phenylalanine‐p‐nitroanilide. The caseinolytic activity of cell‐free extract of L. casei ATCC 393 was about one seventh the caseinolytic activity of intact cells, suggesting that the bulk of the cellular proteinase activity is located in the cell wall. It appears that a metallo aminopeptidase and a probable cysteine one are involved in the hydrolysis of amino acid‐p‐nitroanilide, whereas the endopeptidase activity appears to be related to a cysteine enzyme. Incubation of gels with L‐leucine‐p‐nitroanilide after electrophoresis allowed the revealing of 2 zones of aminopeptidase activity in a strain of L. casei and only one in two others, but in L. plantarum it did not allow the revealing of any. The high proteolytic activities of L. casei compared to those of L. plantarum may explain its more frequent occurence in cheese and its probable role in the ripening of many cheese varities.
Qualitätsveränderungen während der Lagerung von Gemüseerbsen (Pisum sativum L.) 1. Mitt. Äußere und sensorische Qualitätsmerkmale
Authors: Böttcher H. 
Published: November 2006

AbstractWährend der Lagerung von Gemüseerbsen sind bei den Frischmasseverlusten, der kombinierten Druck‐ und Scherfestigkeit und den Boniturnoten für die äußere und sensorische Qualität meist lineare oder mit der Lagerdauer degressiv ablaufende Veränderungen in Richtung eines Qualitätsabbaues festzustellen. Bei den Fäuleverlusten (y = β1(x — z)n; x = Lagerdauer in Tagen; x > z) variiert vor allem die makroskopisch symptomfreie Zeitspanne z sehr stark. Bei allen Merkmalen erweist sich der Einfluß der Lagertemperatur als dominant, bei einigen zusätzlich auch die Ernteform (mit und ohne Hülsen), während jährliche Anbaubedingungen und Sorten in ihrer Bedeutung stark zurücktreten. Lagergut ohne Hülsen zeigt einen schnelleren Rückgang der äußeren Qualität, der sensorischen Qualitätsmerkmale und der fäulnisfreien Zeitspanne z als solches mit Hülsen, so daß die temperaturabhängige Haltbarkeit nur durch zwei verschiedene Regressions‐funktionen mit dem Modell y = β1e‐cθ (Θ = Lagertemperatur in °C; c = Maßzahl der Schnelligkeit des Rückganges der Lagerdauer) dargestellt werden kann. Lagertemperaturen von 0 °C verhindern bei Gemüseerbsen die Nachreifeerscheinungen nicht, verzögern sie aber sehr.
Fractionation of proteins in reconstituted skim‐milk
Authors: Omar M. M. , Śmietana Z. 
Published: November 2006

AbstractProperties of the dried milk were improved when calcium chloride was added to the raw milk prior to the drying process. Solubility, wettability, undenatured whey protein and protein retention indices of the dried milk were increased and the reconstitutability was improved. The elution profile of the protein fractions on a Sephadex G‐100 column differed according to the forward preheating of the raw milk and the addition of calcium chloride.
Charakterisierung und Einsatzmöglichkeiten einer Pektatlyase aus Erwinia carotovora
Authors: Wegener Ch. , Henniger H. 
Published: November 2006

AbstractDas phytopathogene Bakterium Erwinia carotovora bildet bei Kultur im submersen Verfahren extrazellulär Pektatlyase. Der Einfluß von Substrat, Temperatur, Wasserstoffionenkonzentration, Ca+ + und PO4− − − auf die Aktivität dieses Enzyms sowie seine Temperaturstabilität wurden untersucht.Cx‐Cellulase und Protease treten als Nebenaktivitäten auf und wurden teilweise in die Untersuchungen einbezogen.Mögliche Anwendungsgebiete der Pektatlyase in der Lebensmittelindustrie und im wissenschaftlichen Bereich werden diskutiert.
Determination of foaming properties of proteins
Authors: Gassmann B. , Kroll J. , Cifuentes S. 
Published: November 2006

AbstractComparing typical examples of equipment for performing the whipping operation, dispersions and colloidal solutions (13%) respectively of 9 diverse protein based whipping agents were differently aerated, and the foaming properties were determined. Whipping was performed in an industrial manner (batch operation at atmospheric pressure and continuous operation using compressed air and static dispersors) as well as devices widely used in laboratory (household‐type mixer and motor‐driven plungers moving in vertical glass cylinders) were employed. Moreover a new direct current motor‐driven whisk/stirrer, the steplessly adjustable rotation speed of which had been made constant and independent of the rheological properties of the protein solutions to be whipped, was tested.Foaming properties measured suggest that only the new laboratory whipping principle reflects the actual performance of protein based whipping agents and that it is far better adapted to large‐scale processing then the laboratory equipment most commonly used. Optimum foam forming need distinct rotation speeds and stirring times as well as pH values typical for each product. In creating sugar containing protein foams with a high degree of aeration however in no case of laboratory operational conditions the amount of energy and air available for whipping was sufficiently large. Because of the advantages of the new whipping principle over the otherwise tested ones the motor output and the stirring conditions now are being improved.
Die quantitative Bestimmung des Proteingehaltes der Milch mittels Ultraviolettspektralphotometrie 4. Mitt. Die Bestimmung des Proteins aus konservierten Milchproben
Authors: Reichardt W. , Schüler E. , Sieber L. , Schüler E. 
Published: November 2006

AbstractEs wird über die Ergebnisse der quantitativen Bestimmung des Proteingehaltes von konservierten Milchproben mit Hilfe der Ultraviolettspektralphotometrie berichtet. Außer der Konservierung mittels Borsäure, Bronopol, Kupfersulfat, Kaliumdichromat und Ammoniumperoxodisulfat sind die Lagerung der Milch bei Temperaturen unter 0 °C und die Gefriertrocknung geprüft worden. Neben Bronopol und Kupfersulfat erweisen sich bei der Proteinbestimmung mittels Absorbanzmessungen bei 210 nm, 235 und 280 nm sowie 210 und 220 nm besonders die physikalischen Konservierungsverfahren als geeignet. Für die tägliche Justierung des Spektralphotometers wird die Anwendung von Lösungen und Quarzfiltern mit definierter Absorbanz empfohlen.
Comparative study of the influence of an inhibitor of monoaminooxidase (nialamide) on the calcium and phosphorus metabolism in slow and fast‐growing rats
Authors: Campos M. S. , Barrionuevo M. , Reche A. 
Published: November 2006

AbstractNialamide was supplied to slow‐growing animals in doses of 20 mg/100 g of diet for 15 or 30 days. The dose for fast‐growing animals was 10 mg/100 g of diet. The digestive utilization of calcium and phosphorus decreases significantly when adult slow‐growing rats receive the drug for 30 days. This fall is already important in fast‐growing rats when they receive nialamide for only 15 days. In the same way the falls in the retention of calcium and phosphorus in adult rats are only evident when the period of treatment is through 30 days, even females being in negative balance of phosphorus. The amount of calcium retained decreases significantly in fast‐growing rats and so does phosphorus impressively after only 15 days of treatment.
Water binding of proteins in the processing frankfurter‐type sausages Part. 1. Water‐binding ability of freeze‐dried meat fractions containing myofibrillar and stromal proteins
Authors: Heinevetter L. , Gassmann B. , Kroll J. 
Published: November 2006

AbstractAs soon as possible and 48 h after slaughter respectively, from both blade‐bone muscle groups of cattle and pig carcasses the „thick pieces”︁ were excised, extracted, and fractionated. Residues and precipitates from water and salt extracts resulted were freeze‐dried, and an improved Baumann capillary suction apparatus was used to measure their water binding capacity (WBC) with and without addition of 2% sodium chloride and/or heating to 80 °C. With one exception the WBC results followed a relative pattern demonstrating the final residues (stromal proteins and leavings of myofibrillar proteins) binding the highest amount of added water, precipitates of dialysis (mainly containing myofibrillar proteins) a remarkable amount and powdered meats the least. As scanning electron micrographs confirmed, there were no fibrous structures in the precipitates resulted from dialysis of salt solutions (1.0 mol/1). Heating decreased the spontaneous water uptake of all fractions. Addition of sodium chloride had only a noticeable capillary‐suction and swelling effect on unheated samples. Hence swelling of undissolved protein structures (extraction of myosin and possibly of actomyosin) is therefore not the only way for water binding in frankfurter‐type sausages.
Fate of phytic acid during bread making
Authors: Chhabra P. , Sidhu J. S. 
Published: November 2006

AbstractThe effect of malt addition and yeast concentration on the hydrolysis of phytic acid during different stages of bread making has been reported. There was a considerable hydrolysis of phytic acid with the addition of yeast and malt. In the breads of S‐308 and WL‐711 wheat varieties, the loss of phytic phosphorus was 6.6. 8,1; 24.6, 23.0 and 26.6, 27.7% in case of nonyeasted, 1.5% and 3% yeasted dough of whole wheat flour (Atta) respectively. However in white bread, the loss of phytic phosphorus was 14.0 and 18.4; 46.2 and 41.5; 51.7 and 49.4%, in non‐yeasted, 1.5% and 3% yeasted doughs of S‐308 and WL‐711 wheat varieties respectively. A significant loss of phytic acid was observed at a yeast level of 1.5 and 3% and with 0.4% malt addition as compared with the control. Most of the phytic acid was hydrolysed during the fermentation and proofing stages in both types of bread samples.
Phytate hydrolysis during breadmaking in several sorts of Polish bread
Authors: Bartnik M. , Florysiak J. 
Published: November 2006

AbstractThe quantitative changes of phytates taking place during preparation of some sorts of Polish bread were investigated. Sorts of bread chosen for investigation were produced from raw materials with a high phytate content: flour of high extraction, soy bean flour, bran and wheat germ. The content of phytic phosphorus was determined in all components (raw materials), intermediate products and bread. The degree of phytate hydrolysis during preparation of different sorts of bread varied and depended both on the initial amount of these compounds in raw materials used and on the technological process adopted. The most intensive hydrolysis of phytate took place during preparation of rye breads: about 80% of the initial value were hydrolyzed. Almost in all sorts of wheat bread the degree of hydrolysis of phytate was much less: only about 25–60% of these compounds were decomposed. In case of “mixed” bread (wheat and rye one) undecomposed phytate varied from 6% to 49% of the initial value.
Orientierende Untersuchungen zum Stoffwechsel verschiedenartiger akalorischer Verbindungen mit fettähnlichen Eigenschaften bei der Ratte
Authors: Aust L. , Mieth G. , Proll J. , Elsner A. , Behrens H. , Gerhard W. , Brückner J. , Noack R. 
Published: November 2006

AbstractPseudofette auf der Basis vollständig substituierter langkettiger Ester und Ether von Polyhydroxyverbindungen (Saccharose, Triglycerol und Polyethylenglycol) verhalten sich mehr oder weniger indifferent gegen‐über gastrointestinalen Enzymsystemen, entfalten aber zugleich spezifische metabolische Wirkungen auf den Lipidstoffwechsel, insbesondere auf die Cholesterolsynthese in der Leber, den Lipidspiegel des Serums und die fäkale Cholesterolexkretion. Zwischen den getesteten verschiedenartigen Verbindungen bestehen Gemeinsamkeiten und Unterschiede, die als Indizes für eine Struktur‐Wirkungsspezifität zu werten sind. Diesbezügliche Beziehungen werden im Rahmen der Arbeit näher untersucht und kritisch beleuchtet.
Chromatographische Trennungen mono‐ und oligomerer Kohlenhydrate aus biologischen Materialien mit Hilfe von HPLC‐Glassäulen
Authors: Gey M. , Müller W. 
Published: November 2006

AbstractMit Hilfe der HPLC werden mono‐ und oligomere Kohlenhydrate an Silikagelen mit chemisch gebundenen Aminopropylgruppen oder mit in situ imprägniertem Aminmodifier (Piperazin) getrennt. Grundlage der Zuckeranalysen sind selbstgefüllte HPLC‐Säulen aus Glas. Diese zeichnen sich durch hohe Trennleistungen aus, besitzen praktikable Säulenverschlüsse, sind chemisch inert und können in verschiedenen Längen auch mit anderen HPLC‐Sorbentien gepackt werden.An Hand von qualitativen und quantitativen Ermittlungen der Kohlenhydrate in verschiedenen Lebens‐und Genußmitteln und in säurehydrolytisch oder enzymatisch abgebauten Polysacchariden (z. B. Stärke, Regeneratfaser) werden die Einsatzmöglichkeiten der HPLC‐Analysentechnik mit Glastrennsäulen demonstriert.
Studies on freezing of partially dehydrated spinach
Authors: Ragab M. 
Published: November 2006

AbstractSpinach (Spinacea oleracea) was dehydrated at 70 °C, partially dehydrated frozen (dried to its critical moisture ratio and frozen at −20 °C) and frozen at −20 °C. Results indicated that the time required for spinach dehydration was 7 h. Thus, the moisture ratio was 10.1 and 0.054 for the fresh and dried spinach, respectively. The critical moisture ratio during dehydration process was 2.20 after 2.65 h of drying time.Reducing sugars, free amino nitrogen, ash, iron and magnesium were slightly decreased in the partially dehydrated frozen spinach relative to the fresh samples. Dehydration markedly degraded the total chlorophyll, chlorophyll a, chlorophyll b, carotenoides and ascorbic acid whereas the freezing of partially‐dehydrated spinach and freezing process were less effective. On the other hand, freezing of partially dehydrated spinach increased phaeophytin. There were no changes in pH‐values of studied preserved samples.Freezing of partially dehydrated spinach improved the reconstitution of product at 100 °C and at room temperature (25 °C) comparing to dehydration. The drip loss of frozen spinach was 16.4% after 105 min of thawing time.Cooked fresh and frozen spinach were better in colour, flavour, texture, appearance and shape and over‐all acceptability than that of dehydrated cooked one. Moreover, freezing of partially dehydrated spinach improved the aforementioned properties.
Estimation of the biological value of food proteins by a modified equation of the essential amino acid index and the chemical score
Authors: Ihekoronye A. I. 
Published: November 2006

AbstractA modified essential amino acid index equation incorporating a digestibility factor (MEAAI), and a chemical score index (CSI) were developed from the essential amino acid profile of 18 different food proteins hydrolysed by the combined but sequential action of papain and pronase E enzyme systems. The essential amino acid composition of whole egg was used as a reference standard. The following equations were proposed.magnified imageIn which a is the value of the limiting amino acid in the sample, and ae is the corresponding value in whole egg.Both equations were used to calculate the biological value of different protein foodstuffs. There was a close agreement between values obtained using the equations and reported values for the same foodstuffs published in the literature. There was also a close correlation (r = 0.665) between data obtained using MEAAI and those obtained using CSI in estimating biological values, suggesting that either equation could be used reliably and solely to estimate protein biological value of foods.