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See detailTHE POTENTIAL USE OF NEAR-INFRARED SPECTROSCOPY FOR THE QUALITY ASSESSMENT OF EGGS AND EGG PRODUCTS
GALIŞ, Anca; Dale, Laura ULg; Boudry, Christelle ULg et al

in Scientific Works. C Series. Veterinary Medicine (2012), LVIII(3), 294-307

In a context of high productivity, eggs’ quality assessment is necessary for enhanced safety and quality assurance towards the consumers and feedback for producers. The quality assessment of eggs and egg ... [more ▼]

In a context of high productivity, eggs’ quality assessment is necessary for enhanced safety and quality assurance towards the consumers and feedback for producers. The quality assessment of eggs and egg products is performed using destructive and time-consuming methods, therefore the use of rapid tools becomes mandatory, especially in the case of a high production rate. Near Infrared (NIR) spectroscopy is considered a very reliable and rapid technique with large use in food industry. At the farm level, NIR spectroscopy technique would be an interesting tool to determine the chemical and physical properties of eggs, eggshell and internal quality and, moreover, this information may help the layer farm manager when a problem occurs in the flock. Its application in the egg industry is aimed at the quality changes in eggs during storage and quality assessment of the egg products, through the compositional analysis. It is possible and in some cases successful the prediction and/or determination of different parameters such as: protein, total lipid and total solids content (for liquid egg products), polyunsaturated fatty acids (for freeze-dried egg yolk), moisture, fat and protein content (for spray-dried whole eggs). In addition, for the white colored shell eggs, the detection of blood and meat spots is also successful. Further studies with NIR and near infrared hyper spectral imaging system (NIR-HSI) are needed in this direction, as the results obtained until now are very promising for the development of a rapid tool for quality assessment of eggs and egg products. [less ▲]

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See detailChemometric tools for NIRS and NIR hyperspectral imaging
Dale, Laura ULg; Thewis, André ULg; Rotar, Ioan et al

in Bulletin of USAVM Cluj Napoca, Agriculture (2012, September 27), 69(1), 70-76

Nowadays in agriculture, new analytical tools based on spectroscopic technologies are developed. Near Infrared Spectroscopy (NIRS) is a well known technology in the agricultural sector allowing the ... [more ▼]

Nowadays in agriculture, new analytical tools based on spectroscopic technologies are developed. Near Infrared Spectroscopy (NIRS) is a well known technology in the agricultural sector allowing the acquisition of chemical information from the samples with a large number of advantages, such as: easy to use tool, fast and simultaneous analysis of several components, non-polluting, non-invasive and non destructive technology, and possibility of online or field implementation. Recently, NIRS system was combined with imaging technologies creating the Near Infrared Hyperspectral Imaging system (NIR-HSI). This technology provides simultaneously spectral and spatial information from an object. The main differences between NIR-HSI and NIRS is that many spectra can be recorded simultaneously from a large area of an object with the former while with NIRS only one spectrum was recorded for analysis on a small area. In this work, both technologies are presented with special focus on the main spectrum and images analysis methods. Several qualitative and quantitative applications of NIRS and NIR-HSI in agricultural products are listed. Developments of NIRS and NIR-HSI will enhance progress in the field of agriculture by providing high quality and safe agricultural products, better plant and grain selection techniques or compound feed industry’s productivity among others. [less ▲]

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See detailIn vitro determination of prebiotic potential of sugar beet pulp extracted candidates and influence of production method
François, Emmanuelle ULg; Goffin, Dorothée ULg; combo, Agnan Marie-Michelle et al

Poster (2012, June 12)

Various prebiotic hydrolysates were produced starting from sugar beet pulp (SBP) using alternative solution to traditional acidic hydolysis. SBP pectin was first extracted by acid extraction and ethanol ... [more ▼]

Various prebiotic hydrolysates were produced starting from sugar beet pulp (SBP) using alternative solution to traditional acidic hydolysis. SBP pectin was first extracted by acid extraction and ethanol precipitation. Then two technics are used to produced pectic oligosaccharides (POS) : enzymatic hydrolysis (EnzPOS : Rapidase Smart (DSM) ; 50°C ; pH 5) and microwaves-assisted hydrolysis (MW1POS : 104°C/10min/pH 7; MW2POS : 110°C/15min/pH 7). Structural characterization of fractions gave rise to different structural profiles between the four products. Moreover, fermentation parameters obtained in-vitro (A, B, Rmax and Tmax) were also characteristic of the fractions and in favor of a tight relationship between POS structure and POS function. Finally, to avoid solvent use, POS production could be envisaged directly on SBP. Avoiding the step of acidic extraction will allow to meet the green chemistry principles. [less ▲]

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See detailDiscrimination of pure grassland species using NIR Hyperspectral Imaging
Dale, Laura ULg; Bogdan, Anca Dorina; Pacurar, Florin Simion et al

Poster (2012, June 03)

The objective of this study was to discriminate by hyperspectral imaging system, SWIR ImSpector N25E, different pure grassland species (Festuca rubra L., Trifolium repens L., Agrostis capillaris L ... [more ▼]

The objective of this study was to discriminate by hyperspectral imaging system, SWIR ImSpector N25E, different pure grassland species (Festuca rubra L., Trifolium repens L., Agrostis capillaris L., Hieracium aurantiacum L., Arnica montana L.) into grassland species mixtures. All the samples were collected from natural meadows of the National Apuseni Park, Apuseni Mountains, Gârda area (Romania). The samples were air-dried, then prepared using the protocol for NIRS analysis adapted on the scanning linear system. For images acquisition, the Hyper See program was used. Then a model build under MatLab (PLS–DA) was used to discriminate pure species from the mixtures of two or three species. This analysis was carried out in order to see, on images obtained previously from the floristic composition of experimental parcels, if the pure species are or are not recognized according to the spectral data base. More than 99% correct predictions for species discrimination were obtained. This study should guide us to verify if a toxic species is present or not in natural meadows used as food for animals. The floristic composition of a meadow can be determinate only if we have in the data base, spectra for each identified species, as being part of the mixture. [less ▲]

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See detailUse of medium without reducing agent for in vitro fermentation studies by bacteria isolated from pig intestine
POELAERT, Christine ULg; Boudry, Christelle ULg; Portetelle, Daniel ULg et al

in XII International Symposium on Digestive Physiology of Pigs (2012, May)

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See detailBiofuel by-product for poultry diets
Hissette, Mathias ULg; Destain, Jacqueline ULg; Thewis, André ULg et al

Poster (2012, February 28)

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See detailResearch on crude protein and digestibility of Arnica montana L. using conventional NIR spectrometry and hyperspectral imaging NIR
Dale, Laura ULg; Fernandez, Juan Antonio; Vermeulen, Philippe et al

in Journal of Food, Agriculture & Environment (2012), 10(1), 391-396

Arnica montana L. (AM) is considered a medicinal plant, used as hay in feed ration. The aim of this study is to assess the prediction of protein content and in vitro organic matter digestibility value in ... [more ▼]

Arnica montana L. (AM) is considered a medicinal plant, used as hay in feed ration. The aim of this study is to assess the prediction of protein content and in vitro organic matter digestibility value in grass mixtures containing Arnica montana L., and in a second step to check if these values have a positive or negative influence in the mixtures. Crude protein has been selected because it is one of the most important quality parameters of forages as nutritional element used in animal feeding. The protein is required on a daily basis for maintenance, lactation, growth and reproduction, but is important for agriculture too, because a high content of protein makes it an important source of feed. The digestibility is also important, because it refers to the extent to which a feedstuff is absorbed in the animal body as it passes through an animal’s digestive tract. In this study, the Weende system (the Kjeldahl method) for the protein content, together with the enzymatic technique for digestibility, was applied and used in combination with non-destructive methods, like those based on the Near Infrared Spectroscopy (NIRS) or the Near Infrared Hyperspectral Imaging. Based on NIR imaging system data, the PLS-DA was used to discriminate between the classes with AM and classes without AM, as well as to build a model that could be used to predict the composition of mixtures. More than 99% correct prediction for AM was obtained. The crude protein content of the hay determined by classical method decrease from the type of meadow Agrostis capillaris L. - Festuca rubra L. (15.22%) until to the pure sample of Arnica montana L. (11.19%); however, the digestibility was highest in the pure sample of Arnica montana L. (84.13%) and lowest in samples from the type of meadow Agrostis capillaris L. - Festuca rubra L. (57.18%) or in samples with the participation of Arnica montana L. This study should lead to a more important point, which is to verify whether the medicinal properties of Arnica montana L. can be transferred or not to milk production through the dairy cow feed. [less ▲]

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See detailD31-1254: Influence de l'âge et du poids d'abattage sur la qualité organoleptique du poulet de chair à croissance lente en Région wallonne (Rapport d'activités intermédiaire).
De Maeseneire, Coraline ULg; Beckers, Yves ULg; Thewis, André ULg

Report (2011)

Ces dernières années, la progression de la production avicole en Wallonie est, en grande partie, liée au développement de filières dites de qualité différenciée. En 2009, ce sont près de 2.000.000 de ... [more ▼]

Ces dernières années, la progression de la production avicole en Wallonie est, en grande partie, liée au développement de filières dites de qualité différenciée. En 2009, ce sont près de 2.000.000 de poulets qui ont été associés à ce type de production. Cependant, contrairement au poulet standard pour lesquels les pratiques sont très standardisées, les pratiques d’élevage en qualité différenciée peuvent varier, notamment la génétique, l’âge et le poids à l’abattage, le sexe de l’animal, l’accès à un parcours… Ces variations peuvent influencer l’homogénéité de la qualité organoleptique de la viande de poulet au sein d’une même filière ainsi que la perception (et la confiance) des consommateurs vis-à-vis de la viande des poulets qui en sont issus. L’objectif de ce projet est d’étudier et d’objectiver de manière scientifique la qualité organoleptique de la viande de poulet de chair au sein de trois filières avicoles de qualité différenciée afin de fournir aux détenteurs de ces filières des informations quant aux facteurs susceptibles de modifier la qualité organoleptique de leurs produits ainsi que la perception de ceux-ci par les consommateurs. [less ▲]

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See detailPure species of grass discrimination with the help of hyperspectral imaging NIR
Dale, Laura ULg; Rotar, Ioan; Bogdan, Anca Dorina et al

in Agronomy Series of Scientific Research = Lucrari Stiintifice Seria Agronomie (2011, December), 54(2), 23-27

The possibilities to discriminate with hyperspectral imaging system, SWIR ImSpector N25E in grass mixtures of the pure species Festuca rubra L., Trifolium repens L., Agrostis capillaris L., Hieracium ... [more ▼]

The possibilities to discriminate with hyperspectral imaging system, SWIR ImSpector N25E in grass mixtures of the pure species Festuca rubra L., Trifolium repens L., Agrostis capillaris L., Hieracium aurantiacum L., Arnica montana L.was the objective of this study. All the samples were collected from natural meadows, from the National Apuseni Park, Apuseni Mountains, from Gârda area. The samples were naturally dried then prepared using the protocol for NIRS analyze. The model built with PLS–DA, was used to demonstrate wether the classes discrimination between pure species is possible or not. The goal of this study was to see in other images if the pure species are or are not recognized according to the spectral data base. The potential of using the Hyperspectral Imaging NIR (Camera NIR) to discriminate or to identify pure species was confirmed. For this technique the MatLab program was used .A percentage of more than 96% correct prediction for species discrimination was obtained. This study should drive to a more important point, which is to verify whether the toxic species are or are not used as food for animals in the natural meadows. The floristic composition of a meadow can be determined only if we have in the data base, dates for each identified species, as being part of the mix. [less ▲]

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See detailUsefulness of a Vancomycin pretreatment when challenging chickens in order to evaluate anti-Salmonella preparations
Marcq, Christopher ULg; Cambier, Carole ULg; Thewis, André ULg et al

in Ceylan, Necmettin; Ciftci, Ibrahim; Adabi, Shahram (Eds.) 18th European Symposium on Poultry Nutrition: Proceedings (2011, October)

For many years, Salmonella infection models have been developed in chickens with the aim to study the effects of prophylactic or therapeutic measures on the colonization of the gut. However, although the ... [more ▼]

For many years, Salmonella infection models have been developed in chickens with the aim to study the effects of prophylactic or therapeutic measures on the colonization of the gut. However, although the literature includes numerous challenge models, few studies investigated the infection rates among the inoculated population. We have implemented an antibiotic pretreatment of the chickens (vancomycin hydrochloride, 25 mg/bird) as an infection promoter. Indeed, vancomycin affects the normal gut microflora and releases sites for Salmonella at the intestinal epithelium. Two experiments were undertaken and a presence/absence cloacal swab method was used to evaluate cecal colonization. In the first experiment, birds were orally inoculated with Salmonella Typhimurium at 21 days of age. Three inoculum doses (3 × 103, 3 × 106, 3 × 109 cfu/bird) and an uninfected control were compared according to whether or not vancomycin had been used. Higher levels of Salmonella colonization (more than 70 %) were achieved in the gut by pretreating birds with vancomycin before inoculation (P < 0.05). In the second experiment, chicks were inoculated at 7 days of age with 108 cfu/bird after a vancomycin pretreatment, leading to an infection rate of 87.5 %. In conclusion, vancomycin promotes efficiently the percentage of colonized birds in the challenged population, with either young animals or olders. [less ▲]

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See detailResearch on Crude Protein Contents in Medicago Sativa Hay Harvest During 2008-2009 Using FT-NIR Spectrometry
Dale, Laura ULg; Thewis, André ULg; Rotar, Ioan et al

in Bulletin UASVM Agriculture (2011, September 29)

Medicago sativa or Alfalfa is a flowering plant that belongs to Pea Family that is widely grown throughout the world as forage for cattle, and is most often harvested as hay. Medicago Sativa usually has ... [more ▼]

Medicago sativa or Alfalfa is a flowering plant that belongs to Pea Family that is widely grown throughout the world as forage for cattle, and is most often harvested as hay. Medicago Sativa usually has the highest nutritive value of all common hay crops. This work aims to highlight a way for direct, non-destructive analysis of crude protein content in Medicago sativa hays. The primary objective was to build a model for crude protein calibration for Medicago sativa based on FT-NIR spectroscopy. The samples for analysis were collected over two experimental years (2008-2009) from field trials from the research station– Agricultural Development, Jucu. In order to construct the model, references values are needed; for this reason, crude protein content was determined using the classical Kjeldahl method (Kjeltec Auto Analyser, Tecator). The values for crude protein ranged from 12.63% to 19.12% on the dry matter basis. The regression models build was based on Partial Least Squares (PLS) calculated with the SIMPLS algorithm, using different pre-processing techniques and leave-one-out cross validation. Calibration of the two years together drove to a coefficient of determination for cross validation,R2, of 0.965. The robustness of the model was confirmed by applying it to independent samples (external validation) where the coefficient of determination was R2 = 0.977, RMSEP = 0.8. The results obtained indicated that NIRS can be used to determine crude protein, which could be used as a criteria for quality control of Medicago sativa hays. [less ▲]

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