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| Registros recuperados: 25 | |
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| Cabrita, Luís; Fossen, Torgils; Flåten, Geir R.; Andersen, Øyvind M.. |
| The stability of cyanidin 3-glucoside towards five different factors (pH, anthocyanin concentration, sodium chloride concentration, ascorbic acid concentration, Oxygen) was studied during 60 days storage at room temperature using a 2^4-1 reduced factorial design. The influence of each individual parameter on anthocyanin stability was found to vary as a function of time. Sodium chloride and ascorbic acid were, respectively, the variables most contributing to and against anthocyanin stability. Results suggest there may be some degree of interaction between anthocyanin/ascorbic acid, and between pH/Oxygen, affecting anthocyanin degradation. |
| Tipo: ConferenceObject |
Palavras-chave: Anthocyanins; Colour stability; HPLC; UV-Vis; Chemometrics; Reduced factorial design. |
| Ano: 2002 |
URL: http://hdl.handle.net/10198/3210 |
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| Pereira,Antonio Carlos Prestes; Judacewski,Priscila; Coelho,Gabriel; Salem,Renata Dinnies Santos; Marinho,Marina Tolentino; Alberti,Aline; Zielinski,Acácio Antonio Ferreira; Demiate,Ivo Mottin; Nogueira,Alessandro. |
| ABSTRACT: There are no specific technical regulations regarding the identity and quality of white mold surface-ripened cheeses in Brazil. These cheeses are sold both whole (Camembert-type) and in wedges (Brie-type). The aim of the study was to evaluate the physical and chemical properties; technological parameters and microbiological safety of 20 whole cheeses (Camembert-type) and 16 cheese wedges (Brie-type) produced in Brazil. Samples showed a wide range in sodium (91.0-731.0 mg/100 g, cheeses wedges) and calcium (238.0-1100.0 mg/100g, whole cheeses) contents. The cheese groups presented no significant differences in relation to the majority of the analyzed parameters. Listeria monocytogenes was reported in 5% of the whole cheese samples. The other... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cheese quality; Chemometrics; Camembert-type cheese; Brie-type cheese. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782020000100752 |
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| COSTA, M. C. A.; MATALLO, M. B.; FERREIRA, M. M. C.; QUEIROZ, S. C. do N. de; ALMEIDA, S. D. B.; FRANCO, D. A. S.. |
| Abstract: Shikimic acid is a natural organic compound produced in the biochemical pathways of eukaryotic organisms and is generally utilized as a starting material of the antiviral drug Oseltamivir (Tamiflu®). This study shows the results of shikimic acid accumulation in Brachiaria plantaginea, an abundant, grassy plant found in Brazil and other countries in Africa and America, after glyphosate spraying at three different doses. B. plantaginea plants harvested after 6 days of exposure to the herbicide showed that shikimic acid accumulation increased by 345%, on average, compared to unsprayed plants. The combination of near infrared spectroscopy and multivariate analysis using partial least square regression was applied for the quantification of shikimic... |
| Tipo: Artigo em periódico indexado (ALICE) |
Palavras-chave: NIR spectroscopy; PLS regression; Brachiaria plantaginea; Gramínea; Shikimic acid; Chemometrics. |
| Ano: 2016 |
URL: http://www.alice.cnptia.embrapa.br/handle/doc/1066054 |
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| Belo,Renata França Cassimiro; Augusti,Rodinei; Lopes,Paulo Sérgio Nascimento; Junqueira,Roberto Gonçalves. |
| In order to determine the variability of pequi tree (Caryocar brasiliense Camb.) populations, volatile compounds from fruits of eighteen trees representing five populations were extracted by headspace solid-phase microextraction and analyzed by gas chromatography-mass spectrometry. Seventy-seven compounds were identified, including esters, hydrocarbons, terpenoids, ketones, lactones, and alcohols. Several compounds had not been previously reported in the pequi fruit. The amount of total volatile compounds and the individual compound contents varied between plants. The volatile profile enabled the differentiation of all of the eighteen plants, indicating that there is a characteristic profile in terms of their origin. The use of Principal Component Analysis... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chemometrics; Biodiversity; Cerrado native fruit. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-20612013000500018 |
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| Matos, L.C.; Cunha, S.C.; Amaral, J.S.; Pereira, J.A.; Andrade, P.B.; Seabra, R.M.; Oliveira, M.B.P.P.. |
| This paper evaluates the usefulness of three chemical parameters (compositions on tocopherols, sterols and fatty acids) as a tool to discriminate three varietal olive oils (Cvs. Cobrançosa, Madural and Verdeal Transmontana), which are permitted cultivars for the production of ‘‘Trás-os-Montes olive oil’’, a Portuguese protected designation of origin (PDO) product. The olives were collected during the year crop 2000/2001 from the same orchard, in order to eliminate the geographical and climatic influences. Lots with different maturation indices were prepared to allow the evaluation of the ripening stage on the characteristics of varietal olive oils produced from each cultivar. Statistical methods such as multivariate analysis of variance (MANOVA), principal... |
| Tipo: Article |
Palavras-chave: Portuguese virgin olive oil; Ripening; Chemometrics; PDO. |
| Ano: 2007 |
URL: http://hdl.handle.net/10198/754 |
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| BRAGA, D. C.. |
| A adstringência é uma sensação tátil, gerada pela redução da lubrificação na cavidade oral, comumente causada pela interação de compostos fenólicos com as proteínas salivares. No pedúnculo do cajueiro, a adstringência é o principal problema que limita a sua aceitabilidade, sendo um dos maiores obstáculos para a expansão do mercado. Este trabalho buscou caracterizar o perfil sensorial e o perfil de compostos fenólicos de pedúnculos de cajueiro, e por meio de quimiometria, correlaciona-los buscando os possíveis marcadores químicos da adstringência do caju. Foram analisados pedúnculos de nove clones da safra 2017. A análise sensorial foi baseada em uma análise descritiva de provadores previamente selecionados e treinados, registrando a intensidade dos... |
| Tipo: Tese/dissertação (ALICE) |
Palavras-chave: Anacardium occidentale L; UPLC; Análise sensorial; Chemometrics. |
| Ano: 2019 |
URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1106803 |
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| Campbell,Patrícia Morais da Matta; Fernandes Filho,Elpídio Inácio; Francelino,Márcio Rocha; Demattê,José Alexandre Melo; Pereira,Marcos Gervasio; and,Clécia Cristina Barbosa Guimarães; Pinto,Luiz Alberto da Silva Rodrigues. |
| ABSTRACT Quantification of soil properties is essential for better understanding of the environment and better soil management. The conventional techniques of laboratory analysis are sometimes costly and detrimental to the environment. Thus, development of new techniques for soil analysis that do not generate residues, such as spectroscopy, is increasingly necessary as a viable way to estimate a wide range of soil properties. The objective of this study was to predict the levels of organic carbon (OC), clay, and extractable phosphorus (P), from the spectral responses of soil samples in the visible and near infrared (Vis-NIR), medium infrared (MIR), and Vis-NIR-MIR using different preprocessing methods combined with five prediction models. Soil samples were... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Spectral analysis; Reflectance; Chemometrics. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832018000100314 |
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| Lima,Daniel Braga de; Agustini,Bruna Carla; Silva,Eliz Guimarães da; Gaensly,Fernanda; Cordeiro,Rodrigo Becker; Fávero,Maria Luiza Drechsel; Brand,Debora; Maraschin,Marcelo; Bonfim,Tania Maria Bordin. |
| Wine production in the northern Curitiba, Paraná, Brazil, specifically the communes of Colombo and Almirante Tamandaré, is based mainly on the utilization of Vitis labrusca grapes var. Bordô (Ives). Total sugar content, pH, and total acidity were analyzed in red wine samples from 2007 and 2008 vintages following official methods of analysis. Moreover, total phenolic, flavonoid, and tannin contents were analyzed by colorimetric methodologies and the antioxidant activity was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical methodology. Phenolic compounds were identified by high performance liquid chromatography. The total phenolic content of wine samples presented concentrations varying between 1582.35 and 2896.08 mg gallic acid.L-1 since... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Rural; Winery; Chemometrics; Common wine; HPLC; Viniculture. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-20612011000300038 |
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| Santos,Antonio Odair; Kaye,Oren. |
| Leaf water potential is a measure commonly used to describe crop water status and water stress dynamics. The established method for determining leaf water potential using a pressure chamber is cumbersome and subject to operator error as well as time/temperature limitations. These limitations prohibit the intensive sampling required to support proactive water management of commercial crops, including vineyards. Particular for grapevines there is need for faster, more precise and more reliable tools for determining leaf water potential in the field. Portable Near-infrared spectroscopy and multivariate data analysis were applied for the modeling and prediction of leaf water potential in grapevines. For field-grown wine grapes the most significant and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: PLS; Irrigation; Spectrometry; Chemometrics. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162009000300001 |
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| Jacq, Kévin; Perrette, Yves; Fanget, Bernard; Sabatier, Pierre; Coquin, Didier; Martinez-lamas, Ruth; Debret, Maxime; Arnaud, Fabien. |
| In the case of environmental samples, the use of a chemometrics-based prediction model is highly challenging because of the difficulty in experimentally creating a well-ranged reference sample set. In this study, we present a methodology using short wave infrared hyperspectral imaging to create a partial least squares regression model on a cored sediment sample. It was applied to a sediment core of the well-known Lake Bourget (Western Alps, France) to develop and validate a model for downcore high resolution LOI550 measurements used as a proxy of the organic matter. In lake and marine sediment, the organic matter content is widely used, for example, to reconstruct carbon flux variations through time. Organic matter analysis through routine analysis methods... |
| Tipo: Text |
Palavras-chave: Hyperspectral imaging; Chemometrics; Near-infrared spectroscopy; High resolution analysis; Organic matter. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00478/59018/61636.pdf |
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| Registros recuperados: 25 | |
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