66 research outputs found

    Chicken skin gelatine as an alternative to pork and beef gelatines

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    Poultry meat-processing industry produces considerably large amounts of by-products (such as chicken skins, heads, feathers, viscera, bones and legs) containing significant volumes of proteins, particularly collagen. One of the possibilities of advantageous utilization of these under-used by-products can be their application as a raw material rich in collagen for preparation of gelatine, a partial hydrolysate of collagen. In the present study, chicken skins obtained as a by-product from the chicken-breast processing were purified from non-collagen proteins, pigments and fats. Collagen was treated with proteolytic enzymes and the gelatine extraction was performed in distilled water at temperatures of 40, 50, 60, 70 and 80 °C during the constant extraction time of 60 min. The influence of the technological conditions on gelatine functional properties including viscosity, clarity, water holding and fat binding capacity, emulsifying and foaming properties was explored. Certain functional properties of prepared gelatines were significantly affected by the extraction temperature, while on some other properties the extraction temperature had no significant effect. Viscosity of prepared chicken skin gelatines was in the range from 3 to 5.7 mPa.s -1 , clarity from 1.5 to 2%, water holding capacity from 3.8 to 5.6 mL.g -1 , fat binding capacity from 0.9 to 1.3 mL.g -1 , emulsion capacity from 35 to 50%, emulsion stability from 73 to 88%, foaming capacity from 18 to 61% and finally foaming stability was from 4 to 39%. Chicken skin gelatines were compared with commercial food grade pork and beef gelatines. Prepared chicken skin gelatines showed better viscosity, fat binding capacity and foaming stability than mammalian gelatines, while water holding capacity, emulsifying stability and foaming capacity were not as good as in beef and pork gelatines. Emulsifying capacity was comparable with commercial gelatines. Therefore, chicken skin gelatine has the potential as an alternative to traditional gelatines from mammalian sources, such as pork or beef bones and skins. © 2019 Potravinarstvo Slovak Journal of Food Sciences

    Preparation of collagen concentrate from chicken feet

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    The meat-processing industry produces a huge and ever greater amount of involuntary by-products at slaughterhouses, which increase significantly the waste amount. In terms of poultry, these comprise feet, heads, viscera and skin - items that are rich in protein, especially collagen. The latter can be gained through a procedure that involves grinding and defatting raw material, since poultry by-products from meat-processing industry contain a wide range of fat (15 – 70 %). Indeed, it is also necessary to extract other non-collagenic matter, such as pigment and water-soluble proteins. In this study, non-collagen components were removed by treatment of chicken feet in 0.1% NaOH. Three methods of defatting of raw material (applying NaHCO3, lipolytic enzyme and 10 different solvent systems) were tested. The use of solvent mixture of petroleum ether and ethanol proved to be the most efficient method of defatting chicken feet with a residual fat content of approximately 5 %. Collagen concentrate prepared this way possesses the potential to be utilized by commercial sectors, such as the food or pharmaceutical industry. © 2018 Computer Society of the Republic of China. All rights reserved

    Biotechnological preparation of gelatines from chicken feet

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    In the European Union (EU), about five tons of poultry by-product tissues are produced every year. Due to their high collagen content, they represent a significant raw material source for gelatine production. The aim of the paper was the biotechnological preparation of gelatine from chicken feet. The influence of selected process factors on the gelatine yield, gel strength, viscosity, and ash of gelatine was observed; a two-level factor design of experiments with three variable process factors (enzyme addition, enzyme treatment time, and gelatine extraction time) was applied. After grinding and separating soluble proteins and fat, the purified raw material was treated in water at pH 7.5 with the addition of endoprotease at 23 degrees C and after thorough washing with water at 80 degrees C, gelatine was extracted. By the suitable choice of process conditions, gelatine with high gel strength (220-320 bloom), low ash content (s can be prepared. The extraction efficiency was 18-38%. The presented technology is innovative mainly by the enzymatic processing of the source raw material, which is economically, technologically, and environmentally beneficial for manufacturers. Chicken gelatines are a suitable alternative to gelatines made from mammals or fish, and can be used in many food, pharmaceutical, and biomedical applications.Internal Grant Agency of the Faculty of Technology, Tomas Bata University in Zlin [IGA/FT/2019/003

    On the equivalence of soft wavelet shrinkage, total variation diffusion, total variation regularization, and SIDEs

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    Soft wavelet shrinkage, total variation (TV) diffusion, total variation regularization, and a dynamical system called SIDEs are four useful techniques for discontinuity preserving denoising of signals and images. In this paper we investigate under which circumstances these methods are equivalent in the 1-D case. First we prove that Haar wavelet shrinkage on a single scale is equivalent to a single step of space-discrete TV diffusion or regularization of two-pixel pairs. In the translationally invariant case we show that applying cycle spinning to Haar wavelet shrinkage on a single scale can be regarded as an absolutely stable explicit discretization of TV diffusion. We prove that space-discrete TV difusion and TV regularization are identical, and that they are also equivalent to the SIDEs system when a specific force function is chosen. Afterwards we show that wavelet shrinkage on multiple scales can be regarded as a single step diffusion filtering or regularization of the Laplacian pyramid of the signal. We analyse possibilities to avoid Gibbs-like artifacts for multiscale Haar wavelet shrinkage by scaling the thesholds. Finally we present experiments where hybrid methods are designed that combine the advantages of wavelets and PDE / variational approaches. These methods are based on iterated shift-invariant wavelet shrinkage at multiple scales with scaled thresholds

    Thermal stability of prepared chicken feet gelatine gel in comparison with commercial gelatines

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    Gelatine is, due to its functional properties, currently widely used not only in the food industry (in the production of confectionery, dairy products, canned food) but also in pharmacy (soft and hard capsules) and cosmetics (creams, lotions) where it applies its ability to form thermoreversible gel stronger than most other gelling agents. What is more, it provides further excellent properties including emulsifying, foaming, stabilizing, film-forming, water and fat binding, texturizing, thickening, and adhesive attributes which makes it a very important hydrocolloid. Gelatine is obtained from the raw material of animal tissues containing collagen, usually mammalian skin or bones. For religious reasons in some countries, pork or bovine gelatine must be replaced by an alternative form, such as poultry or fish gelatine. The quality of gelatine is assessed mostly by the strength of gelatine gel which strongly depends on ambient temperature or humidity. Extraction conditions may also significantly affect the quality of gelatine. This study examined possible changes in the strength of gelatine gels prepared from laboratory-produced chicken feet gelatine and compared them with commercially available pork and beef gelatines at temperatures of 23, 29, and 35 °C at 60 and 80% humidity. While at 23 °C thermal stability of prepared chicken gelatine was monitored higher than in commercial gelatines, experiments at 29 and 35 °C provided equivalent results for chicken and commercial gelatines. Therefore, prepared chicken gelatine offers a significant potential to become an alternative to traditional gelatines. The information about gelatine gels thermal stability is of great importance for applications not only in the food; but also in the pharmaceutical industry. © 2020 Potravinarstvo Slovak Journal of Food Sciences

    Cross-disease innate gene signature: Emerging diversity and abundance in RA comparing to SLE and SSc

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    Overactivation of the innate immune system together with the impaired downstream pathway of type I interferon-responding genes is a hallmark of rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and systemic sclerosis (SSc). To date, limited data on the cross-disease innate gene signature exists among those diseases. We compared therefore an innate gene signature of Toll-like receptors (TLRs), seven key members of the interleukin (IL)1/IL1R family, and CXCL8/IL8 in peripheral blood mononuclear cells from well-defined patients with active stages of RA (n=36, DAS28 >= 3.2), SLE (n=28, SLEDAI>6), and SSc (n=22, revisedEUSTARindex>2.25). Emerging diversity and abundance of the innate signature in RA patients were detected: RA was characterized by the upregulation of TLR3, TLR5, IL1RAP/IL1R3, IL18R1, and SIGIRR/IL1R8 when compared to SSc (Pcorr<0.02) and of TLR2, TLR5, and SIGIRR/IL1R8 when compared to SLE (Pcorr<0.02). Applying the association rule analysis, six rules (combinations and expression of genes describing disease) were identified for RA (most frequently included high TLR3 and/or IL1RAP/IL1R3) and three rules for SLE (low IL1RN and IL18R1) and SSc (low TLR5 and IL18R1). This first cross-disease study identified emerging heterogeneity in the innate signature of RA patients with many upregulated innate genes compared to that of SLE and SSc.Web of Science2019art. no. 357580

    Diffusion-inspired shrinkage functions and stability results for wavelet denoising

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    We study the connections between discrete 1-D schemes for non-linear diffusion and shift-invariant Haar wavelet shrinkage. We show that one step of a (stabilised) explicit discretisation of nonlinear diffusion can be expressed in terms of wavelet shrinkage on a single spatial level. This equivalence allows a fruitful exchange of ideas between the two fields. In this paper we derive new wavelet shrinkage functions from existing diffusivity functions, and identify some previously used shrinkage functions as corresponding to well known diffusivities. We demonstrate experimentally that some of the diffusion-inspired shrinkage functions are among the best for translation-invariant multiscale wavelet denoising. Moreover, by transferring stability notions from diffusion filtering to wavelet shrinkage, we derive conditions on the shrinkage function that ensure that shift invariant single-level Haar wavelet shrinkage is maximum-minimum stable, monotonicity preserving, and variation diminishing

    Nonlinear structure tensors

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    In this article we introduce nonlinear versions of the popular structure tensor, also known as second moment matrix. These nonlinear structure tensors replace the Gaussian smoothing of the classical structure tensor by discontinuity-preserving nonlinear diffusions. While nonlinear diffusion is a well-established tool for scalar and vector-valued data, it has not often been used for tensor images so far. Two types of nonlinear diffusion processes for tensor data are studied: an isotropic one with a scalar-valued diffusivity, and its anisotropic counterpart with a diffusion tensor. We prove that these schemes preserve the positive semidefiniteness of a matrix field and are therefore appropriate for smoothing structure tensor fields. The use of diffusivity functions of total variation (TV) type allows us to construct nonlinear structure tensors without specifying additional parameters compared to the conventional structure tensor. The performance of nonlinear structure tensors is demonstrated in three fields where the classic structure tensor is frequently used: orientation estimation, optic flow computation, and corner detection. In all these cases the nonlinear structure tensors demonstrate their superiority over the classical linear one. Our experiments also show that for corner detection based on nonlinear structure tensors, anisotropic nonlinear tensors give the most precise localisation

    Proposal of processing chicken by-products tissues into food-grade collagen

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    The consumption of poultry has been on rise and shows no signs of diminishing; hence greater importance is placed on subsequently treating animal by-products, which are divided into 3 categories. Such materials are produced in large quantities, and with respect to its biological nature, needs to be handled in a way that prevents polluting the environment. Finding an effective use for this by-products, for example, as a raw material which could be processed into other products, would constitute an ideal way to address the issue. Indeed, it contains large amounts of protein, especially collagen, as widely applied in the food sector and other industries. By-products that boast a high proportion of collagen include the skin of poultry, which can be obtained by a procedure involving controlled isolation of any undesirable components, i.e. fats, soluble non-collagenous proteins and pigments. Hence, what was once considered waste is turned into a valuable raw material rich in collagen, and further transformation of the latter translates into soluble collagen and collagen hydrolysate. As an example, chicken skin, which is high in fats (84%), can be effectively defatted by shaking of grinded raw material in a mixture of solvents for a certain period of time, the result being collagen with the residual fats content of approximately 14% using mixture of solvents petroleum ether and ethanol. The use of acetone brought a similar effect (18%). However, the use of NaHCO3solution did not lead to the acceptable result (81%). The shaking of the raw material in water solution with lipolytic enzymes was also tested. Three types of enzymes in different concentrations were used for this purpose, but the residual fats content was also much higher compared to chemical solvents (48 - 69%). Possibilities for further processing of the raw material into products with potential applications in industry were also proposed. © 2020 Czech Environment Management Center. All rights reserved.Univerzita Tomáše Bati ve Zlíně: IGA/FT/2020/002; European Regional Development Fund, FEDER: CZ.1.05/2.1.00/03.008

    Active optical fibers doped with ceramic nanocrystals

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    Erbium-doped active optical fiber was successfully prepared by incorporation of ceramic nanocrystals inside a core of optical fiber. Modified chemical vapor deposition was combined with solution-doping approach to preparing preform. Instead of inorganic salts erbium-doped yttrium-aluminium garnet nanocrystals were used in the solution-doping process. Prepared preform was drawn into single-mode optical fiber with a numerical aperture 0.167. Optical and luminescence properties of the fiber were analyzed. Lasing ability of prepared fiber was proofed in a fiber-ring set-up. Optimal laser properties were achieved for a fiber length of 20~m. The slope efficiency of the fiber-laser was about 15%. Presented method can be simply extended to the deposition of other ceramic nanomaterials
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