bluuebunny/crossref_metadata_2025_split huggingface dataset:
Standardisierungsfähige Prüfmethode zur Bestimmung von Aflatoxin M1 in Milch und Milchprodukten (Wissenschaftlicher Kurzbericht)
Authors: Bauer S. , Schindler D. , Kroll J. 
Published: November 2006

AbstractMykotoxine werden unter bestimmten stofflichen und klimatischen Bedingungen von verschiedenen Schimmelpilzarten gebildet und mit Lebens‐ und Futtermitteln von Mensch und Tier aufgenommen. Zahl‐reiche Erkrankungen — Mykotoxikosen — gehen auf diese Mykotoxinaufnahme zurück [1, 2].Aflatoxin M1 wird im Stoffwechsel des tierischen Organismus durch Hydroxylierung aus mit dem Futter aufgenommenen Aflatoxin B1 neben anderen Produkten erhalten und bevorzugt mit der Milch ausgeschieden. Die durchschnittliche Übergangsrate — carry over — vom Aflatoxin B1 im Futter zum Aflatoxin M1 in der Milch beträgt 1 bis 3% [3, 4]. Da bei der Be‐ und Verarbeitung der Milch eine Entfernung bzw. Umsetzung von Aflatoxin M1 nicht nachgewiesen werden konnte, kommt der Bestimmung dieses Mykotoxins in Trinkmilch, Milchpulver und anderen Milchprodukten eine große Bedeutung zu [1, 3, 5, 6].Im Rahmen der vorliegenden Arbeit wird auf der Grundlage von in der Literatur beschriebenen dünnschichtchromatographischen Verfahren [7‐11] eine Methode erarbeitet, die wegen ihres geringen materiellen und zeitlichen Aufwandes, ihrer Empfindlichkeit, Richtigkeit und Genauigkeit als Standardmethode ZUT Bestimmung von Aflatoxin M1 in Milch und Milchprodukten geeignet ist.Die Untersuchungen werden an den Modellsystemen Aflatoxin M1/dest. Wasser und Aflatoxin M1/Vollmilchpulver/dest. Wasser zunächst mit den in der Literatur beschriebenen Methoden durchgeführt. Im Ergebnis dieser Untersuchungen wird festgestellt, daß die Methode von Serralheiro u. a. [11] den anderen Methoden [7–10] hinsichtlich Aufwand und Wiederfindungsrate überlegen ist. Auf der Grundlage dieser Erkenntnisse wird insbesondere durch Variation der chromatographischen Bedingungen eine eigene Methode entwickelt, die sich durch eine Nachweisempfindlichkeit von 0,1 μg/l, eine Wiederfindungsrate von 85% und eine relative Standardabweichung von 6% auszeichnet. Die Eignung dieser neuen Methode zur Standardisierung konnte im Rahmen einer Ringanalyse gemäß TGL 24131/01‐04 [12] mit einer Wiederholbarkeit von 0.08μg/l und einer Vergleichbarkeit von 0,2 μg/l nachgewiesen werden.
Study on taste substances of tomato Part 3. Sensory evaluations
Authors: Petró‐Turza M. , Teleky‐Vámossy Gy. 
Published: November 2006

AbstractThe authors wished to clarify the role played by amino acids and minerals in the formation of the taste of tomatoes by means of sensory evaluation of model solutions. In preparing the model solutions the results of the thorough analysis of two tomato cultivars (K‐549 and Mokka) were taken into account. It was established that the effect of free amino acids on the pH and the buffer capacity of the system cannot be neglected, in addition in the presence of minerals they affect taste advantageously, contributing to the development of tomato character. The effect of pyrrolidone‐carboxylic acid (PCA) on the taste was also investigated. The sensory threshold value of PCA in aqueous solution was found to be 500 ppm. The quality of taste was found sour, tart and occasionally bitter. On adding PCA to tomato puree the appearance of off‐flavour was not observed, indeed it was found that in certain concentrations it affected the taste of lower quality purees advantageously.
Study of the electronic and structural properties of the chemical compounds in garlic aroma
Authors: Bersuker I. B. , Dimoglo A. S. , Gorbachov M. Yu. , Greni A. I. , Vysotskaya L. E. , Mikhailova T. V. 
Published: November 2006

AbstractBy means of the electron‐topologic approach, combining the methods of the pattern recognition theory and the electron and geometric description of the molecular systems under consideration, the totality of 52 sulphur‐containing organic compounds is investigated. The electron‐topologic activity fragment found allows to characterize correctly all the compounds of the totality and to describe successfully the influence of the structural changes in the molecular systems investigated on the garlic odor appearance.
Volatile flavour substances of apricot and their changes during ripening
Authors: Tóth‐Markus M. , Boross F. , Blazsó M. , Kerek M. 
Published: November 2006

AbstractAroma content and composition of different Hungarian and foreign apricot cultivars were studied. Volatile flavour substances were isolated by simultaneous steam distillation‐extraction. GC and GC/MS analysis of the aroma extracts revealed 40 components, 12 of them have been reported for the first time in apricots. The changes in the aroma composition of the cultivar “Hungarian kajszi” during ripening were also studied.
Role of zinc in regulating the testicular function Part 3. Histopathological changes induced by dietary zinc deficiency in testes of male albino rats
Authors: Hafiez A. A. , El‐Kirdassy Z. H. M. , El‐Malkh N. M. , El‐Zayat E. M. I. 
Published: November 2006

AbstractZinc deficiency affects the testicular tissues adversely. The testes of zinc‐deficient rats showed variable degrees of degeneration compared to both control and zinc‐supplemented ones. Initially, there was an early pronounced spermatic arrest followed by a series of degeneration of the cellular layers constituting the seminiferous tubules in the zinc‐deficient rats. Degenerative changes were additionally demonstrated in the interstitial tissue cells of the zinc‐deficient rats. These histopathological observations in testes of zinc‐deficient rats run in parallel provide an additional support to our previous publications in which we recorded a significant reduction in both serum and testicular levels of testosterone in the same group of animals, since spermatogenesis in rodents appeared to depend primarily on testosterone level.
Use of oyster shell as calcium supplement. Part 1. Effect on the utilization of gossypol‐containing cotton seed cake by the chicken
Authors: Aletor V. A. , Onibi O. E. 
Published: November 2006

AbstractThe comparative utilization of cottonseed cake (CSC) diets supplemented with varying levels of oyster shell (0.00, 1.50, 3.00 and 4.50%) as a source of calcium, and groundnut cake (GNC) based diet were evaluated in a feeding trial using 100 day‐old HYPECO broiler‐chicks. The response criteria included performance, carcass traits and economics of production.The weight gains at the end of the trial were not significantly different. However, feed consumption significantly (P < 0.5) increased with increasing dietary calcium. Feed consumption was significantly (P < 0.05) correlated with dietary calcium levels with r = 0.96. Feed efficiency and protein efficiency ratio were significantly (P < 0.05) better in the GNC diets than CSC based diets in spite of the oyster shell supplementation of the latter. Both nitrogen retention and apparent nitrogen digestibility were not significantly influenced.The percent dressed weight, percent eviscerated weight and the relative weights of the thigh, drumstick, chest, back, head and belly fat were not significantly influenced by the dietary treatment. Only the relative weight of the shank was significantly (P < 0.05) influenced.The cost‐benefit analysis showed that although it was cheaper to formulate CSC diets, profits were identical with GNC diets when fed to the chicks.It was suggested that CSC could be a good substitute for GNC because of the ready availability of the former. Dietary calcium of up to 1.82% was beneficial in the utilization of the CSC.
Utilization of freeze‐shocked lactobacilli for enhancing flavour development of Ras cheese
Authors: Aly M. E. 
Published: November 2006

AbstractFreeze‐shocked cultures of Lactobacillus helveticus or Lactobacillus casei were added at levels of 1% and 2% to Ras cheese milk prior to renneting as an adjunct starter to enhance flavour development of cheese. These additives did not affect the gross chemical composition of the cheeses but increased the formation of soluble nitrogenous compounds, free volatile fatty acids, the flavour intensity and improved the body characteristic. Also, the counts of bacterial groups (total, proteolytic and lipolytic) of the cheese treated with freeze‐shocked lactobacilli were higher than in the control. Moreover, the ripening period was reduced to be 2 months compared with 4 months required for the control cheese. Also, using freeze‐shocked culture of L. helveticus was the most effective in this respect.
Fortschrittsbericht. Neuere Entwicklungen auf ausgewählten Gebieten der Lebensmittelbiotechnologie
Authors: Ruttloff H. 
Published: November 2006

AbstractAnhand der Literatur sowie eigener Arbeiten wird ein Überblick zum derzeitigen internationalen Kenntnisstand auf einigen speziellen Gebieten der Lebensmittelbiotechnologie gegeben. Besondere Berücksichtigung finden in diesem Zusammenhang vor allem ernährungswissenschaftlich relevante Probleme. Nach einer Einführung (hierbei Erörterung auch fermentationstechnischer, gentechnischer sowie proteintechnischer Entwicklungen) werden folgende Schwerpunkte behandelt: Einzellerproteine (Speisepilze, Hefen, Bakterien, Schimmelpilze, phototrophe Mikroorganismen), lösliche Enzyme, Enzyminhibitoren, immobilisierte Systeme (Enzyme, Zellen, neue Prozesse und Produkte), Aminosäuren, Süßungsmittel, mikrobielle Polysaccharide als Hydrokolloide, organische Genußsäuren, pflanzliche Zell‐ und Gewebekulturen sowie Aromen und Geschmacksstoffe (Enzyme, Mikroorganismen, pflanzliche Systeme).
Study on some trace elements content of certain internal organs and muscles of porkers
Authors: Krelowska‐Kułas M. 
Published: November 2006

AbstractThe aim of the investigations was the determination of the lead, cadmium, copper, zinc and iron content. It was found that lead and cadmium content in the kidneys and livers of porkers from the Cracow region was several times higher than in the case of porkers from an agricultural region (control). The average lead concentration in 35% of kidneys and livers coming from the porkers of the Cracow region exceeded the permissible norm.
Growth characteristics of enterococci isolated from Laban Rayeb
Authors: Hagrass A. E. A. , Fayed E. O. , Aly A. A. , El‐Samragy Y. A. 
Published: November 2006

AbstractEleven strains of Enterococcus (Streptococcus) faecalis isolated from Laban Rayeb, a type of fermented milk, had been studied when grew in milk. Enterococcus (Streptococcus) faecalis strains 19 and 22 were the most active strains in the production of lactic acid, acetaldehyde and diacetyl. Both strains exhibited a high proteolytic activity besides a good clean flavour. Based on the obtained results, Enterococcus (Streptococcus) faecalis 19 and 22 could be used to bring about the lactic fermentation during the manufacture of some cultured dairy products.
Effect of gamma irradiation and water activity on mycotoxin production of Alternaria in tomato paste and juice
Authors: Aziz N. H. , Farag S. , Hassanin M. A. 
Published: November 2006

AbstractGamma‐irradiation, water activity (aw) and incubation temperature were found to affect the production of tenuazonic acid (TZA) by Alternaria alternata in tomato paste and juice. By increasing the irradiation doses, the dry weight as well as TZA decreased greatly until complete inhibition at 4 kGy. Greatest production of TZA occurred at 0.98 aw(57.5 μg/g and 26.3 μg/g) for both tomato paste and juice, respectively, at 25°C. Changing temperature and awaltered the relative amounts of TZA produced in tomato paste und juice by unirradiated and irradiated conidia of A. alternata. Only trace amount of TZA was detected at 0,98 aw(1.50 μg/g) by 3 kGy‐irradiated conidia in tomato paste, while it was inhibited completely in juice. Increasing gamma‐irradiation doses and decreasing water activities decreased greatly or inhibited TZA production in both tomato paste and juice.
Determination of synthetic colourants by capillary isotachophore sis
Authors: Karovicova J. , Polonsky J. 
Published: November 2006

AbstractIt has been found that during technological processing of foods their colours vary from the original or required state to a large extent. Products lose their attractive appearance but consumers demand products with stable standard colour [1]. As natural pigments are mostly sensitive to environmental effects, synthetic colourants have quickly found extensive utilization in food industry.The quantity of additives in foods and therefore also of synthetic colourants must be controlled. Ye et al. [2] and Reynolds et al. [3] have used HPLC, including the use of diode‐array detectors, to determine synthetic dyes. Barros et al. [4] have approached such determination using differential pulsed polarography. We have investigated capillary isotachophoresis analysis for the separation, identification and determination of synthetic colourants in different food products.
Plasma and liver free amino acids in rats fed glycine supplemented casein diets
Authors: Petzke K. J. , Noack J. , Proll J. , Albrecht V. 
Published: November 2006

AbstractDifferences in the amino acid composition appear to be largely responsible for various actions of food proteins of vegetable or animal origin on lipid metabolism and atherogenesis. But it remains still unclear which amino acids or combinations of amino acids are mainly influencing the physiologic effects observed by mechanisms which has yet to be satisfactorily explained [1‐3]. Glycine has been shown to modify lipid metabolism in liver and blood lipid parameters significantly when supplemented to casein diets alleviating in some studies hypercholesterolemia and atherosclerosis [3–5].The present study investigates the effects of glycine supplemented casein diets on plasma and liver free amino acid patterns. The findings to be presented here support the possible role of amino acids in respect of modifying the risk factors for arteriosclerotic complications.
Biochemical dynamics and hypocholesterolemic action of Hibiscus sabdariffa (Karkade)
Authors: El‐Saadany S. S. , Sitohy M. Z. , Labib S. M. , El‐Massry R. A. 
Published: November 2006

AbstractMale albino rats were fed on a mixture of cholesterol and cholic acid for 12 weeks to induce hypercholesterolemia, then Karkade was administered at 5 and 10 % for 9 weeks to evaluate its hypocholesterolemic and hypolipemic effect. The experimental parameters include total lipids, cholesterol, triglycerides and phospholipids. Liver and kidney functions were also investigated in normal, hypo‐ and hypercholesterolemic rats administered Karkade. A remarkable progress (lowering effect) in the level of different lipid fractions was noticed in spite of the continued cholesterol and cholic acid loading during the treatment. However, blood phospholipids were increased after Karkade administration. Hypercholesterolemia has resulted in an effect on the activity of liver and kidney functions. Therefore, the measurement of serum enzyme activity has provided a useful tool for hepatic recovery. Although the administration of Karkade at 5 and 10 % induced a significant decrease in the activity of serum GOT and serum GPT, alkaline and acid phosphatase as well as total serum protein, the values nearly returned to the initial levels after 9 weeks of Karkade aministration.
Autoxidation of stored soybean lecithin
Authors: Reblova Z. , Pokorny J. , Panek J. 
Published: November 2006

AbstractSoybean phospholipid concentrates, generally called lecithins, can be stored for long time in a refrigerator or even at room temperature, without apparent changes of sensory properties, and their peroxide value usually remains low. This behaviour is related to the antioxidant activity of phospholipids in refined vegetable oils [1] which was attributed to their synergistic effect in presence of tocopherols [2, 3]. Both the low peroxide content and the inhibitory activity may be explained, at least partially, by the hydroperoxide decomposing activity of phospholipids [4], the rate of hydroperoxide decomposition being proportinal to the square root of the hydroperoxide content [5]. Therefore, we have analysed several samples of lecithin to find out whether the presence of phospholipids only affects the rate of hydroperoxide accumulation or the formation of total oxidation products, respectively.
Untersuchungen zur Aufbereitung von Lebensmittel‐ und Umweltproben für die Rückstandsbestimmung von Pestiziden und PCB mittels kontinuierlicher Wasserdampfdestillation
Authors: Hemmerling Ch. , Risto Ch. , Augustyniak B. , Jenner K. 
Published: November 2006

AbstractDie Aufarbeitung von Wasser‐, Boden‐ und Lebensmittelproben mit einer modifizierten Glasapparatur zur simultanen Wasserdampfdestillation/Lösungsmittelextraktion wird erprobt. Zusatzversuche mit 22 vorwiegend halogenhaltigen Pflanzenschutzmitteln und PCB ergaben nach einer Destillationsdauer von 1,5 h bei Wasserproben bzw. bis zu 5 h bei Boden‐ und pflanzlichen Lebensmittelproben gute bis sehr gute Wiederfindungen. Durch den geringen Lösungsmittelverbrauch (<10 ml) ist dieses Verfahren umweltfreundlich und kostengünstig und für viele Fragestellungen als schnelle Screeningmethode anwendbar.
Use of scanning electron microscopy techniques in the biocatalyst immobilization
Authors: Toldra F. , Lequerica J. L. 
Published: November 2006

AbstractScanning Electron Microscopy (SEM) has become a routine technique for the characterization of inert support materials for biocatalyst immobilization as well as for the observation of immobilized cells, especially cell colonization and cell‐support interaction. SEM is expected to have important future applications in the observation of immobilized enzymes and will prove a useful technique in the engineering design and scale‐up of immobilized biocatalyst systems.
Charakterisierung des Enzymspektrums von Pektinenzym‐ und Cellulase‐Präparaten sowie deren Wirkung auf die Zellwand‐polymeren der Möhre. 3. Mitt. Gelchromatographische Differenzierung löslicher Zellwandpolysaccharide
Authors: Schönfeld A. , Behnke U. 
Published: November 2006

AbstractDie alkoholunlösliche Substanz von Möhren wird mit einigen Pektinenzymen allein oder in Kombination mit Cellulase hydrolysiert. Im löslichen Hydrolysat werden die sauren und neutralen Saccharide vor und nach Differenzierung durch Gelchromatographie bestimmt. Eine Prüfung auf Korrelationen zwischen Einzelenzymaktivitäten (Polygalacturonase, Cellulase, Xylanase) der komplex zusammengesetzten Enzymgemische und den jeweils freigesetzten sauren bzw. neutralen Sacchariden ergibt nur im Fall der Polygalacturonase (Freisetzung saurer Galacturonide) eine schwache Signifikanz. Es besteht eine wesentliche synergistische Wirkung durch die jeweiligen Enzymkomponenten. Bei günstiger Enzymkombination liegen überwiegend Mono‐ und niedermolekulare Oligosaccharide als Abbauprodukte neben noch ungelösten Restanteilen vor.
Zur Wirkung unterschiedlicher Proteindiäten auf Lebensdauer und ausgewählte biochemische Parameter von alten Ratten
Authors: Medovar B. Ja. , Petzke K. J. , Semesko T. G. , Albrecht V. , Grigorov Ju. G. 
Published: November 2006

AbstractUntersucht wurde der Einfluß verschiedener Proteindiäten (NP‐Diät: 19 % Proteinanteil, davon 72 % tierischer Herkunft, LP‐Diät: 8,8 % Proteinanteil ausschließlich pflanzlicher Herkunft) auf einige Stoffwechselparameter sowie auf die Lebenserwartung (50 %ige Sterberate als Basis) von 23 Monate alten Ratten. Die LP‐Diät bewirkte im Langzeitfütterungsexperiment (200 Tage) eine Erhöhung der Quotienten der freien Aminosäuren Glycin + Alanin zu Tyrosin + Phenylalanin + verzweigtkettige Aminosäuren in der Leber, sowie niedrigere Phenylalaninspiegel und ein um das 12fache höheres Phenylalanin / Tyrosin‐Verhältnis bei gleichzeitig niedrigeren Harnstoffspiegeln in Serum und Leber. Hierzu kommen deutlich niedrigere Dopaminspiegel in lateralen und medialen und niedrigere Serotoninspiegel in lateralen Hypothalamusbereichen gegenüber der NP‐Diät. Im Noradrenalingehalt konnten keine Veränderungen gemessen werden. Die Überlebensrate in der LP‐Gruppe war um 24 % höher. Die Ergebnisse sprechen für eine größere Bedeutung der Nahrungsproteinkomponente für die Lebenserwartung als bisher angenommen. Die Beteiligung zentraler Regulationsmechanismen deutet sich an.
Effects of sodium metabisulphite, hydrogen peroxide and heat on aflatoxin B1 in lafun and gari ‐ two cassava products
Authors: Adegoke G. O. , Babalola A. K. , Akanni A. O. 
Published: November 2006

AbstractSodium metabisulphite and hydrogen peroxide alone or in combination with heat (50–70°C) were found to be effective in degrading aflatoxin B1 (AFB1) in lafun and gari. Hydrogen peroxide (H2O2) at a concentration of 3 % in the aqueous phase gave a 12.5 % degradation of aflatoxin B1 in lafun and at 50°C, degradation levels of 25 % and 50 % were obtained with 6.0 and 9.0 % H2O2, respectively. When sodium metabisulphite was applied during the production of gari (a fermented cassava product heated to 50‐70°C during production) AFB1 degradation levels were found to be 65.8 %, 60.9 %, 41.5 % and 36.6 %, respectively, for sodium metabisulphite levels of 1.0 %, 0.8 %, 0.5 % and 0.3 %.
Phenolic constituents in major fractions of tropical rapeseed
Authors: Bibi Nizakat , Sattar Abdus , Chaudry M. A. 
Published: November 2006

AbstractPhenolic constituents in major fractions such as seed, cotylendons and hulls of commercial rapeseed varieties Ganyou‐5, Westar, Raya‐brown and Raya yellow grown under tropical conditions in Pakistan, were determined. Quantitative determination in percentage of sinapine, catechin, tannic acid and total phenolics as well as in absorption units at 550 nm of procyanidine, proanthocyanidine and flavan‐4‐ols in relation to different extractants such as methanol, methanol‐HCl and their totals, were made. These varieties and their fractions widely varied in different phenolic constituents in respect of extractants used. Hulls of all cultivars contained higher levels of catechin, procyanidine, pronanthocyanidine and flavan‐4‐ols while lower amounts of sinapine, tannic acid and total phenols than the cotylendons. Cotylendons and hulls in seeds of raya‐brown were exceptionally high in procyanidine.
Effect of free fatty acids on the flavour of frying oil
Authors: Ledahudec J. , Pokorný J. 
Published: November 2006

AbstractLauric acid imparts soapy taste to edible oil and to fried bread in the concentration of less than 1 g·kg‐1, palmitic acid and stearic acid taste neutral in the concentration of up to 20 g·kg‐1, oleic acid is neutral in the same concentration range, while purified linoleic acid tastes slightly bitter, and the flavour of linolenic acid is bitter and rancid at the concentration of 1 g·kg‐1.
Some simple methods of home processing and their implication with weaning foods
Authors: Moussa Wafaa A. , Tadros Margerite D. , Mekhael Kamal G. , Darwish Abd El‐Moneim H. , Shakir Ahmed H. , Abd El‐Rehim Emam A. 
Published: November 2006

AbstractOne of the most practical solutions to combat protein energy malnutrition (PEM) in low income groups is the intelligent mixing of cereals and legumes to make available low cost weaning foods of high nutritional quality. One of the main obstacles to increase energy and nutrient density of weaning foods of cereals and legumes is the bulk factor. In this study some simple methods of home processing to improve the nutritional quality of the home prepared weaning foods were tested and the processed weaning foods were chemically and biologically evaluated.Biochemical evaluation revealed that the germination of wheat raised its protein and fat and reduced carbohydrate, while there was almost no change on lentils. Comparing germination with a special “chapati” process, protein and fat content were higher in the formula processed by the former method, while minerals were higher in the same formula but processed by the latter method. Biological evaluation of the formula processed by the two different methods showed that germination got the highest PER and NPU compared with chapati process figures were (2.02 and 81.0) and (1.70 and 40.0) respectively. Although further research is needed, germination of ingredients of weaning foods of vegetable origin seems to be a good option of the simple home processing technique.