14 research outputs found

    Effect of Pasteurization on Rheological Properties of White Carrot Juice

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    AbstractThe rheological behaviour of untreated and pasteurized white carrot juice was modelled to investigate the influence of temperature on viscosity and its fluid type. The research was conducted using a rotational viscometer at shear rates ranging from 1 to 100 s-1 and temperatures between 10 and 60°C. The rheological behaviour of untreated white carrot juice was well described by the Newtonian model while the pasteurized juice showed a pseudoplastic behaviour and was satisfactorily fitted to Ostwald-de Waele model. The Arrhenius equation adequately described the effect of temperature on the viscosity. The activation energies were depended on kind of fluid and were 15.41 and 5.90kJ/mol for untreated and pasteurized white carrot juice, respectively

    Technology for Apple Pomace Utilization within a Sustainable Development Policy Framework

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    The aim of this study was to develop a concept, within the framework of sustainable agriculture, for utilizing apple pomace as a valuable raw material in food production. The proposal includes a description of the production technology of four food products together with the characteristics of their chemical composition, wholesome compounds, and physical properties. These new products were developed on the basis of apple pomace and wheat bran. In the developed technology, heat treatment in a convection oven, treatment with infrared radiation, and two types of barothermic treatments, i.e., extrusion and granulation, were implemented as the principal methods. All of the proposed technologies allow for the use of pomace for the production of food products to be made directly in the home plant and are relatively easy to implement in small processing facilities. It was found that the product consisting of fragmented apple pomace (mass fraction: 75%) and wheat bran (mass fraction: 25%), obtained using infrared radiation treatment, had the greatest value in terms of wholesome characteristics among the products obtained. This product had high contents of fiber and simple sugars, the highest content of polyphenols among the obtained products, and the ability to scavenge free radicals. It was also the only one with partially preserved vitamin C. The proposed method for processing pomace for food is in line with the sustainable agriculture movement

    Technology for Apple Pomace Utilization within a Sustainable Development Policy Framework

    No full text
    The aim of this study was to develop a concept, within the framework of sustainable agriculture, for utilizing apple pomace as a valuable raw material in food production. The proposal includes a description of the production technology of four food products together with the characteristics of their chemical composition, wholesome compounds, and physical properties. These new products were developed on the basis of apple pomace and wheat bran. In the developed technology, heat treatment in a convection oven, treatment with infrared radiation, and two types of barothermic treatments, i.e., extrusion and granulation, were implemented as the principal methods. All of the proposed technologies allow for the use of pomace for the production of food products to be made directly in the home plant and are relatively easy to implement in small processing facilities. It was found that the product consisting of fragmented apple pomace (mass fraction: 75%) and wheat bran (mass fraction: 25%), obtained using infrared radiation treatment, had the greatest value in terms of wholesome characteristics among the products obtained. This product had high contents of fiber and simple sugars, the highest content of polyphenols among the obtained products, and the ability to scavenge free radicals. It was also the only one with partially preserved vitamin C. The proposed method for processing pomace for food is in line with the sustainable agriculture movement

    Noise Measurements Of Resistors With The Use Of Dual-Phase Virtual Lock-In Technique

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    Measurement of low-frequency noise properties of modern electronic components is a very demanding challenge due to the low magnitude of a noise signal and the limit of a dissipated power. In such a case, an ac technique with a lock-in amplifier or the use of a low-noise transformer as the first stage in the signal path are common approaches. A software dual-phase virtual lock-in (VLI) technique has been developed and tested in low-frequency noise studies of electronic components. VLI means that phase-sensitive detection is processed by a software layer rather than by an expensive hardware lock-in amplifier. The VLI method has been tested in exploration of noise in polymer thick-film resistors. Analysis of the obtained noise spectra of voltage fluctuations confirmed that the 1/f noise caused by resistance fluctuations is the dominant one. The calculated value of the parameter describing the noise intensity of a resistive material, C = 1·10−21 m3, is consistent with that obtained with the use of a dc method. On the other hand, it has been observed that the spectra of (excitation independent) resistance noise contain a 1/f component whose intensity depends on the excitation frequency. The phenomenon has been explained by means of noise suppression by impedances of the measurement circuit, giving an excellent agreement with the experimental data

    Noise Properties of Graphene-Polymer Thick-Film Resistors

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    Graphene is a very promising material for potential applications in many fields. Since manufacturing technologies of graphene are still at the developing stage, low-frequency noise measurements as a tool for evaluating their quality is proposed. In this work, noise properties of polymer thick-film resistors with graphene nano-platelets as a functional phase are reported. The measurements were carried out in room temperature. 1/f noise caused by resistance fluctuations has been found to be the main component in the specimens. The parameter values describing noise intensity of the polymer thick-film specimens have been calculated and compared with the values obtained for other thick-film resistors and layers used in microelectronics. The studied polymer thick-film specimens exhibit rather poor noise properties, especially for the layers with a low content of the functional phase

    Ocena wybranych parametrów technicznych procesu tłoczenia oleju z nasion soi

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    The objective of the paper was to determine the impact of the value of the oil pressing pressure with the cold pressing method in a screw press on the pressing course and performance. Varied values of pressure were obtained through the use of three replaceable attachments of the pressing unit with a varied diameter of the outlet conduit (ф1=2 mm, ф2=4 mm and ф3=6 mm). The soya oil pressing process perfor-mance was determined in relation to the applied attachment and the soya cultivar. Seeds of 7 Polish non-genetically modified soya cultivars constituted research material. It was proved that both variable pressure values and the used soya cultivars have impact on the pressing performance. Based on the analysis of the obtained research results it was proved that varied technical parameters and soya cultivars influence both the process performance and the remaining parameters and pressing conditions.Celem pracy było określenie wpływu zmiennych wartości ciśnienia wytłaczania oleju metodą tłoczenia na zimno w prasie ślimakowej na przebieg i wydajność tłoczenia. Zróżnicowane wartości ciśnienia uzyskiwano poprzez zastosowanie trzech wymiennych końcówek zespołu tłoczącego o różnej średnicy kanału wylotowego (ф1=2 mm, ф2=4 mm i ф3=6 mm). Określano wydajność procesu tłoczenia oleju sojowego w zależności od zastosowanej końcówki oraz odmiany soi. Materiałem do badań były nasiona 7 polskich odmian soi niemodyfikowanej genetycznie. Wykazano, iż wpływ na efektywność wytłaczania mają zarówno zmienne wartości ciśnienia jak i wykorzystane odmiany soi. W oparciu o analizę uzyskanych wyników badań potwierdzono, iż zróżnicowane parametry techniczne i odmiany soi mają wpływ zarówno na wydajność tego procesu, jak i jego pozostałe parametry i warunki tłoczenia

    Noise Properties Of Thick-Film Conducting Lines For Integrated Inductors

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    Studies of noise properties of thick-film conducting lines from Au or PdAg conductive pastes on LTCC or alumina substrates are reported. Experiments have been carried out at the room temperature on samples prepared in the form of meanders by traditional screen-printing or laser-shaping technique. Due to a low resistance of the devices under test (DUTs), low-frequency noise spectra have been measured for the dc-biased samples arranged in a bridge configuration, transformer-coupled to a low-noise amplifier. The detailed analysis of noise sources in the signal path and its transfer function, including the transformer, has been carried out, and a procedure for measurement setup self-calibration has been described. The 1/f noise component originating from resistance fluctuations has been found to be dominant in all DUTs. The analysis of experimental data leads to the conclusion that noise is produced in the bends of meanders rather than in their straight segments. It occurs that noise of Au-based laser-shaped lines is significantly smaller than screen-printed ones. PdAg lines have been found more resistive but simultaneously less noisy than Au-based lines
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