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Fourier transform infrared spectroscopy coupled with chemometrics for the monitoring of virgin olive oil quality during storage up to 18 months
No full textInternational audienceThis study examines the feasibility of using mid infrared (MIR) spectroscopy for monitoring the quality of 14 Moroccan virgin olive oil samples belonging to three (3) varieties, originated from three (3) geographical origins, extracted with different systems, irrigated and fertilised with different modes.The application of principal component analysis (PCA) and factorial discriminant analysis (FDA) on MIR spectra dataallowed to discriminate perfectly the samples according to their storage time with 96.87% of correct classification.The obtained results were confirmed following the application of three different multivariate regression tools namely partial least squares regression (PLSR), principal component regression (PCR) and support vector machine regression (SVMR) applied on MIR spectra data, since excellent prediction of R2 = 0.99 and RMSEP = 17.05 days was observed. In addition, the evaluation of the effectiveness of MIR spectroscopy to predict the chemical parameters allowed to obtain excellent validation models with R2 ranging between 0.98 and 0.99 for free acidity, peroxide value, chlorophyll level, k232 and k270
A preliminary study on the potential of front face fluorescence spectroscopy for the discrimination of Moroccan virgin olive oils and the prediction of their quality
No full textInternational audienceThis study examines the feasibility of using front face fluorescence spectroscopy (FFFS) to authenticate 41 virgin olive oil (VOO) samples collected from 5 regions in Morocco during 2 consecutive crop seasons
Application of new emerging techniques in combination with classical methods for the determination of the quality and authenticity of olive oil: a review
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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Preliminary study on the potential application of Fourier‐transform mid‐infrared for the evaluation of overall quality and authenticity of Moroccan virgin olive oil
No full textInternational audienceBACKGROUND Olive oil provides a wide range of health-promoting compounds. The quality of olive oil is an even more complex concept as it is affected by several factors, such as variety, season, stage of maturation, extraction processing, and so on. The main objective of this study was to determine the potential of chemical and mid-infrared spectroscopy techniques to determine the quality and authenticity of virgin olive oil (VOO). For this, we studied 41 VOOs originating from five regions of Morocco (Fez/Meknes, Eastern, Northern, Beni-Mellal/Khenifra, and Marrakech/Safi) and produced using different agricultural and technological conditions during two successive crop seasons (2015-2016 and 2016-2017).RESULTS By applying principal component analysis and factorial discriminant analysis with leave-one-out validation to the mid-infrared spectroscopy, clear discrimination between VOO samples according to their geographic origin and variety was observed, with correct classification rates of 91.87% and 91.87% being observed respectively. The application of partial least-squares regression to mid-infrared and chemical data sets allowed excellent prediction of free acidity, peroxide value, k(270), and chlorophyll level with R-2 of 0.99, 0.97, 0.98, and 0.93 respectively, and good prediction of k(232) (R-2 = 0.84).CONCLUSION The results demonstrate that mid-infrared spectroscopy coupled with chemometric tools could be used as a rapid screening tool for evaluating the overall quality and authenticity of VOO. (c) 2020 Society of Chemical Industr
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Two extraction methods of essential oils: conventional and non-conventional hydrodistillation
No full textThe traditional extraction of essential oils exposes plant material to high temperatures for hours, which may lead to the production of artifacts, even originating unpleasant odors and loss of quality. In addition, this procedure is energy-consuming, which makes it an expensive method. The present work has been focused on a method that combines hydrodistillation and subsequent extraction with water vapor and volatiles of essential oil in the same apparatus, that we called non-conventional hydrodistillation (NCH). Three aromatic plants were used: Rosmarinus officinalis leaves (X-1), Lavandula angustifolia flowers (X-2), and Citrus aurantium leaves (X-3). In the processes, the operating parameters as vegetal mass moisture, total sum vegetal mass used, and water flux rate have been fixed at 17 %, 100 g, and 0.97 L/h, respectively. The extraction process was made using mixture experimental design, taking into account the plants used (one plant, binary and ternary combinations); the position of the plants in the apparatus to study essential oils' yields. The results showed that NCH of binary and ternary mixtures allows obtaining higher yields than expected with values superior to 2 % for the following combinations: X-1:X-2 (50:50), X-1:X-3 (50:50); X-1:X-2:X-3 (33:33:33) and X-1:X-2:X-3 (0.67: 0.16:0.16). The new NCH had a high kinetic coefficient k (2.98) and lower extraction time (70 min) than conventional hydrodistillation (CH), which means less energy consumption.info:eu-repo/semantics/publishedVersio
L\u27aviculture non industrielle au Maroc: Une étude par enquête dans la région de Rabat-Salé-Kénitra
Get PDFTraditional poultry farming is an important alternative for the increase in the animal protein contribution in the rural environment. Surveys were carried outin 98 poultry farms in four provinces of the Rabat-Salé-Kénitra region to characterize the traditional poultry farming in this region. These surveys focused on the characteristics of the farms (socio-economic status of the farmer, the farming method, and the composition of the poultry, the avian species, the infrastructure, the business, the feed, the diseases, the mortality rate and the treatments used).The analysis of the collected data showed that women are primarily responsible for poultry farming (80%); 94.9% of the surveyed breeders have no technical training in poultry farming; the experience in the surveyed farms varies between 10 and 50 years (p <0.0001); high numbers of poultry are included in the majority (49%) between 20 and 100 individuals; poultry feed in the study areas was based primarily on natural resources (28%), followed by bran (23%) and wheat (22%); the most common diseases in the “Beldi chicken” are coccidiosis (22%) and avian influenza (21%), followed by E. coli (16%) and smallpox (11%). The majority of breeders practice traditional treatments (63%), whereas only 37% of breeders used veterinary treatments (p <0.001). Thus, poor production performance is recorded in these farms: a median mortality rate of 10% is related to the characteristics of the farms and farmers (Technical training, level of hygiene practiced in farms, etc.). Diseases, lack of supervision and financial means are the main constraints of the sector. Keywords: Traditional poultry farming, poultry diseases, traditional treatments, surveys, food, Rabat-Salé-KénitraDes enquêtes ont été menées dans 98 exploitations avicoles réparties sur 4 provinces de la région de Rabat-Salé-Kénitra afin de caractériser les élevages avicoles traditionnels de cette région. Ces enquêtes ont porté sur les caractéristiques des élevages (état socio-économique de l’éleveur, mode d’élevage, la composition de la basse-cour, les espèces aviaires, l’infrastructure, la commercialisation, l’alimentation, les maladies, le taux de mortalité et les traitements utilisés). L’analyse des données recueillies a montré que les femmes sont les principales responsables des élevages avicoles (80%) ; 94.90% des éleveurs enquêtés n’ont aucune formation technique en aviculture; l’expérience dans les élevages enquêtés varie entre 10 et 50 ans (p<0,0001); les effectifs de volailles élevés sont compris en majorité (48,98%) entre 20 et 100 individus ; la nourriture de la volaille dans les régions étudiées était basée essentiellement sur les ressources naturelles (28%), suivi par le son (23%) et le blé (22%); les maladies les plus répondues chez le poulet Beldi sont la coccidiose (22%) et la peste aviaire (21%), suivis par E.Coli (16%) et la variole (11%). La majorité des éleveurs pratiquent des traitements traditionnels (63%), alors que seuls 37 % des éleveurs avaient recours aux traitements vétérinaires (p < 0,001). Ainsi, de faibles performances de production sont enregistrées dans ces élevages : une valeur médiane du taux de mortalité de 10 %, a une relation avec les caractéristiques des exploitations et des exploitants (Formation technique, niveau d’hygiène pratiqué dans les élevages etc..). Les maladies, le manque d’encadrement et de moyens financiers constituent les principales contraintes de la filière.
Mots clés: L\u27aviculture traditionnelle, maladies avicoles, traitements traditionnels, enquête, alimentation, Rabat-Salé-Kénitr
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