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161.
Research was undertaken to study the technological properties of six carrageenan fractions and their usefulness as fat substitutes in frankfurter type sausages. In the first stage of the experiment hardness of gels made of 3% solutions of carrageenan preparations with different pH (5.5, 6.0 and 6.5) was evaluated. The highest Fmax. values were noted in gels obtained from G-WG carrageenan (kappa I fraction). In the second stage of the study frankfurter type sausages were produced, containing 20% and 10% of fat in meat batter with or without (control) kappa I carrageenan (G-WG). Carrageenan as a fat substitute caused a reduction in cooking and storage weight losses, increased hardness, gumminess and chewiness. All frankfurters produced with carrageenan, irrespective of fat content, were characterized by significantly higher sensory evaluation scores for texture, color and taste in comparison to control sausages. 相似文献
162.
163.
Monika Grote Hans Georg Fromme 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1982,175(3):191-194
Summary By morphometric analysis of transmission electron-micrographs the degree of cell wall swelling in rehydrated vegetables (carrots and green beans) was examined as a function of various blanching, dehydration and storing parameters. The results show a clear correlation between food technology parameters and cellular morphology of the samples.
The present study was supported by grant No. 3668 of the Arbeitsgemeinschaft Industrieller Forschungsvereinigungen e. V. and Forschungskreis der Ernährungsindustrie e. V. 相似文献
Morphometrische Messungen der Zellwandquellung bei rehydratisierten Karotten und grünen Bohnen: Der Einfluß verschiedener Blanchier-, Trocknungs- und Lagerparameter
Zusammenfassung Mit Hilfe morphometrischer Messungen an transmissionselektronen-mikroskopischen Bildern wurde der Grad der Zellwandquellung bei rehydratisiertem Trockengemüse (Karotten und grünen Bohnen) in Abhängigkeit von verschiedenen Blanchier-, Trocknungs- und Lagerbedingungen analysiert. Die Ergebnisse lassen eine eindeutige Korrelation zwischen lebensmitteltechnologischen Verfahren und der Zellmorphologie der Proben erkennen.
The present study was supported by grant No. 3668 of the Arbeitsgemeinschaft Industrieller Forschungsvereinigungen e. V. and Forschungskreis der Ernährungsindustrie e. V. 相似文献
164.
Barbara Kramhöller Monika Pischetsrieder Theodor Severin 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1993,197(3):227-229
When dextrins or starch are heated with propyl-amine in neutral aqueous solution at 100–130° C a brown colouration is observed. From the reaction mixture 3-hydroxy-2-methyl-1-propyl-4(1H)-pyridone11, 1,4-dihy-dro-2-methyl-1-propyl-4-propylimino-3-pyridinol12 and 5-hydroxymethyl-1-propyl-pyrrol-2-aldehyde13 can be extracted with organic solvents and separated by HPLC. Enzymatic hydrolysis effects the release of 1(3-hydroxy-1-propyl-2-pyrrolyl)-1-ethanone10 from a glycosidically bound precursor.
Maillard Reaktionen von Dextrinen und Stärke
Zusammenfassung Erhitzt man Dextrine oder Stärke mit Propylamin in neutraler wäßriger Lösung auf 100–130 °C, so beobachtet man eine braune Färbung. Aus der Reaktionsmischung lassen sich 3-Hydroxy-2-methyl-1-propyl-4(1H)-pyridon11, 1,4-Dihydro-2-methyl-1-pro-pyl-4-propylimino-3-pyridinol12 und 5-Hydroxymethyl-1-propyl-pyrrol-2-aldehyd13 mit organischen Lösungsmitteln extrahieren und durch HPLC trennen. Nach enzymatischer Hydrolyse der wasserlöslichen Fraktion ist 1(3-Hydroxy-1-propyl-2-pyrrolyl)-1-ethanon10 isolierbar.相似文献
165.
The development of dislocation configurations in a single-crystal superalloy during creep and especially the shear mechanism
of theγ′ phase is investigated by a transmission electron microscopy (TEM) study. Detailed analysis shows that at low strains and
at coherent interfaces, shearing occurs by dissociation of matrix dislocations at theγ/γ′ interfaces, while at high strains and incoherent interfaces, cutting of theγ′ phase is achieved by antiphase boundary (APB) coupled dislocation pairs. The results are discussed in their connection to
creep behavior. 相似文献
166.
Michael Spenke Heinz Muhlenbein Monika Mevenkamp Friedemann Mattern Christian Beilken 《Software》1984,14(11):1095-1107
An efficient and systematic LL(1) error recovery method is presented that has been implemented for an LL(1) parser generator. Error messages which provide good diagnostic information are generated automatically. Error correction is done by discarding some input symbols and popping up some symbols from the parsing-stack in order to restore the parser to a valid configuration. Thus, symbol deletions and insertions are simulated. The choice between different possible corrections is made by comparing the cost of the inserted (popped) symbols with the reliability value of the recovery symbol (the first input symbol that is not discarded). Our concept of reliability is based on the observation that input symbols differ from each other in their ability to serve as recovery points. A high reliability value of a symbol asserts that it was probably not placed in the input by accident. So it is reasonable not to discard that symbol but to resume parsing. This is done even if a string with high insert-cost has to be inserted before that symbol in order to fit it to the part of the program that has already been analysed. The error recovery routine is invoked only when an error is detected. Thus, there is no additional time required for parsing correct programs. Error-correcting parsers for different languages, including Pascal, have been generated. Some experimental results are summarized. 相似文献
167.
The infrared spectra of four samples of soft brown coal of Miocene age which varied systematically both in colour and in attrinite:densinite ratio have been determined. The spectra of the coals were very similar to each other as were those of the coals which had been benzoylated or acetylated and this suggests that the chemical structures of attrinite and densinite must be similar and that little difference exists between the lithotypes. 相似文献
168.
Manjubala I Woesz A Pilz C Rumpler M Fratzl-Zelman N Roschger P Stampfl J Fratzl P 《Journal of materials science. Materials in medicine》2005,16(12):1111-1119
Bone and cartilage generation by three-dimensional scaffolds is one of the promising techniques in tissue engineering. One approach is to generate histologically and functionally normal tissue by delivering healthy cells in biocompatible scaffolds. These scaffolds provide the necessary support for cells to proliferate and maintain their differentiated function, and their architecture defines the ultimate shape. Rapid prototyping (RP) is a technology by which a complex 3-dimensional (3D) structure can be produced indirectly from computer aided design (CAD). The present study aims at developing a 3D organic-inorganic composite scaffold with defined internal architecture by a RP method utilizing a 3D printer to produce wax molds. The composite scaffolds consisting of chitosan and hydroxyapatite were prepared using soluble wax molds. The behaviour and response of MC3T3-E1 pre-osteoblast cells on the scaffolds was studied. During a culture period of two and three weeks, cell proliferation and in-growth were observed by phase contrast light microscopy, histological staining and electron microscopy. The Giemsa and G?m?ri staining of the cells cultured on scaffolds showed that the cells proliferated not only on the surface, but also filled the micro pores of the scaffolds and produced extracellular matrix within the pores. The electron micrographs showed that the cells covering the surface of the struts were flattened and grew from the periphery into the middle region of the pores. 相似文献
169.
Berná J Leigh DA Lubomska M Mendoza SM Pérez EM Rudolf P Teobaldi G Zerbetto F 《Nature materials》2005,4(9):704-710
Nature uses molecular motors and machines in virtually every significant biological process, but demonstrating that simpler artificial structures operating through the same gross mechanisms can be interfaced with-and perform physical tasks in-the macroscopic world represents a significant hurdle for molecular nanotechnology. Here we describe a wholly synthetic molecular system that converts an external energy source (light) into biased brownian motion to transport a macroscopic cargo and do measurable work. The millimetre-scale directional transport of a liquid on a surface is achieved by using the biased brownian motion of stimuli-responsive rotaxanes ('molecular shuttles') to expose or conceal fluoroalkane residues and thereby modify surface tension. The collective operation of a monolayer of the molecular shuttles is sufficient to power the movement of a microlitre droplet of diiodomethane up a twelve-degree incline. 相似文献
170.
Tomas Cajka Katerina RiddellovaEva Klimankova Monika CernaFrantisek Pudil Jana Hajslova 《Food chemistry》2010
An automated head-space solid-phase microextraction (HS-SPME)-based sampling procedure, coupled to gas chromatography–ion trap mass spectrometry (GC–ITMS), was developed and employed for fast characterisation of olive oil volatiles. In total, 914 samples were collected, over three production seasons, in north-western Italy—Liguria (n = 210) and other regions—in addition to the rest of Italy, Spain, France, Greece, Cyprus, and Turkey (n = 704) with the aim to distinguish, based on analytical (profiling) data, the olive oils labelled as “Ligurian” (protected denomination of origin region, PDO) from all the others (“non-Ligurian”). For the chemometric analysis, linear discriminant analysis (LDA) and artificial neural networks with multilayer perceptrons (ANN-MLP) were tested. Employing LDA, somewhat lower recognition (81.4%) and prediction (61.7%) abilities were obtained. The classification model was significantly improved using ANN-MLP. Under these conditions, the recognition (90.1%) and prediction (81.1%) abilities were achieved. The diagnostic value of the data obtained by one-dimensional GC–ITMS were compared with those generated by two-dimensional gas chromatography–time-of-flight mass spectrometry (GC × GC–TOFMS), allowing a comprehensive analysis of olive oil volatiles. 相似文献