Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
Más filtros











Intervalo de año de publicación
1.
J Food Sci Technol ; 59(8): 3307-3311, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35872728

RESUMEN

The present work aims to develop encapsulated NaCl in carnauba wax for bread application, to reduce the salt utilization and assess its impacts on the rheological dough parameters and saltiness perception. Encapsulated salt was obtained blending salt crystals and molten Carnauba wax. Four different bread formulations were produced: 2.0% non-encapsulated salt; 2.0% Encapsulated Salt; 1.5% Encapsulated Salt; 1.0% Encapsulated Salt. Farinograph and alveograph analyses were performed to assess the dough rheology parameters and sensory analysis was conducted to evaluate saltiness. Encapsulation was effective to control Na+ ions release. They vary from 17 to 32 ppm the dissolution of sodium ions in the non-encapsulated and encapsulated samples, respectively. The alveograph and farinograph analyses showed that the 1.5E bread formulation was the closest to the control sample in rheological properties. Finally, a sensory analysis showed no difference in the saltiness perception between control and 1.5% encapsulated salt (4.65 and 4.69 respectively), indicating that carnauba wax encapsulated salt effectively reduced until 35% of salt the bread without changing the saltiness.

2.
Food Chem ; 339: 127917, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32950898

RESUMEN

Andean beans (Phaseolus vulgaris) chemical compositions and cooking characteristics contribute to a healthy diet. The objective of this study was to evaluate the influence of chemical composition on the cooking quality of 14 Andean beans genotypes with different seed coat colors. More specifically, water retention (WR), cooking time (CT), and solids released in the broth, were analysed. WR values ranged from 128.4% to 160.7% and CT ranged from 13.7 (BRS Embaixador) to 21.7 min (KID44). Andean beans showed variability in chemical composition, mainly starch content (39.43 g 100 g-1, BRS Realce to 51.92 g 100 g-1, LP15-04) and polymer composition. The profile of starch and interactions among minerals and chemical compounds influenced the cooking profiles than do the individual compounds. Andean beans traits of cooking, mainly CT, were influenced by their chemical composition; however they can be incorporated into diets without drastic changes in preparation methods.


Asunto(s)
Culinaria/métodos , Phaseolus/química , Almidón/análisis , Amilopectina/análisis , Amilosa/análisis , Genotipo , Minerales/análisis , Análisis Multivariante , Phaseolus/genética , Phaseolus/metabolismo , Semillas/química , Semillas/genética , Semillas/metabolismo
3.
Clin Cosmet Investig Dent ; 12: 61-70, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32161504

RESUMEN

BACKGROUND: When a phosphoric acid is used, before applying an adhesive system, it is known that obtaining an effective adhesion to the root canal walls is a challenge. The aim of the present study was to evaluate the influence of phosphoric acid viscosity and application mode on the push-out bond strength (BS) values of fiberglass post to root dentin. The conditioning pattern on the root dentin was also evaluated. MATERIALS AND METHODS: The roots of 44 endodontically treated premolars were divided into 4 groups, of eleven teeth each, according to the combination of the main factors: phosphoric acid viscosity (liquid or gel) and application mode (passive or sonic). After application of the two-step etch-and-rinse adhesive system, the fiberglass posts were cemented with a dual-cure resin-cement. Roots were sectioned transversely into six 1-mm slices for push-out BS test at 0.5 mm/min. Some roots of each group were selected for evaluation of the conditioning pattern by scanning electron microscopy. BS results (three-way ANOVA and Tukey's test) and the conditioning pattern (Kruskal-Wallis test and Mann-Whitney test) were statistically evaluated (α= 0.05). RESULTS: The highest BS value was observed with a liquid phosphoric acid under sonic application mode (p < 0.05), being all other groups similar to one another (p < 0.05). Also, the highest BS value was observed in the cervical third, followed by the medium and the apical thirds (p < 0.05). The sonic application produced better smear layer removal and opening of dentinal tubules for both viscosities (p = 0.015). CONCLUSION: A better bonding of fiberglass posts to root canals can be achieved when the post spaces are conditioned with a liquid phosphoric acid under sonic application.

4.
Acta Physiol (Oxf) ; 227(3): e13328, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31177629

RESUMEN

AIM: Foetal growth restriction (FGR) is associated with endothelial dysfunction and cardiovascular diseases in adult subjects. Early vascular remodelling and epigenetic changes occurring on key endothelial genes might precede this altered vascular function. Further, it has been proposed that oxidative stress during development may determine some of these epigenetic modifications. To address this issue, we studied the in vivo and ex vivo vascular function and Nos3 promoter DNA methylation in arteries from eight-month-old guinea-pig born from control, FGR-treated and FGR-NAC-treated pregnancies. METHODS: Femoral and carotid arteries in vivo vascular function were determined by Doppler, whilst ex vivo vascular function and biomechanical properties were assessed by wire myography. Levels of eNOS mRNA and site-specific DNA methylation in Nos3 promoter in aorta endothelial cells (AEC) were determined by qPCR and pyrosequencing respectively. RESULTS: FGR adult showed an increased femoral vascular resistance (P < .05), stiffness (P < .05) and arterial remodelling (P < .01), along with an impaired NO-mediated relaxation (P < .001). These effects were prevented by maternal treatment with NAC. Endothelial-NOS mRNA levels were decreased in FGR adult compared with control and FGR-NAC (P < .05), associated with increased DNA methylation levels (P < .01). Comparison of Nos3 DNA methylation in AEC showed a differential methylation pattern between foetal and adult guinea-pigs (P < .05). CONCLUSION: Altogether, these data suggest that adult vascular dysfunction in the FGR does not result from early changes in Nos3 promoter DNA methylation, but from an altered vessel structure established during foetal development.


Asunto(s)
Retardo del Crecimiento Fetal , Óxido Nítrico Sintasa de Tipo III/metabolismo , Animales , Fenómenos Biomecánicos , Arterias Carótidas/patología , Metilación de ADN , Epigénesis Genética , Femenino , Arteria Femoral/patología , Desarrollo Fetal , Regulación del Desarrollo de la Expresión Génica , Cobayas , Óxido Nítrico Sintasa de Tipo III/genética , Embarazo
5.
Food Chem ; 292: 275-280, 2019 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-31054676

RESUMEN

This research aimed to correlate the composition of green Arabica coffee beans with the sensory quality coffee brews. The chemical composition of green Arabica coffee bean (66 samples) from three coffee quality contests was analyzed by near-infrared spectroscopy. Coffee brews with lower quality scores were correlated with high levels of caffeine, protein, chlorogenic acids and total titratable acidity (TTA) in the green coffee beans. High sucrose/TTA and cafestol/kahweol ratios in the green coffee beans were usually associated with higher scores for the coffee brews. By multivariate analysis techniques, the samples were separated into groups according to production years indicating a strong influence of the environmental conditions on the chemical composition. The profile of the composition of the crude coffee can be indicative of the sensory quality of the coffee brews, relevant information for producers and industry since the green beans are the material used for trading and purchasing coffee.


Asunto(s)
Cafeína/análisis , Café/química , Espectroscopía Infrarroja Corta , Ácido Clorogénico/análisis , Análisis por Conglomerados , Diterpenos/análisis , Calidad de los Alimentos , Análisis de Componente Principal
6.
Food Res Int ; 114: 72-80, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30361029

RESUMEN

Coffee production is the result of the relationship between local environmental conditions and coffee cultivars that grow in this place. Coffee plants develop original physico-chemical and sensory characteristics that together with the agricultural techniques practiced by growers define the terroir. The objective of this study was to describe the typicity of coffee prepared by coffee growers from seven coffee terroirs in Paraná, Brazil. The terroir categorization was based on the local latitude, longitude, altitude and annual average temperature. Coffee samples were prepared by the coffee growers according to their agricultural techniques. A multiple factor analysis (MFA) was applied to the groups of variables of the green and roasted coffee bean physico-chemical and sensory attributes. The variability in environmental conditions was sufficient to modify the green and roasted coffee bean characteristics and sensory attributes. The terroir description obtained with MFA description compared to that obtained with individual groups of variables was different among terroirs. Roasted coffee variables and sensory attributes caused the greatest differences. The individual use of these groups of variables may result in non-representative descriptions of coffee from different terroirs. Mandaguari and Ivaiporã terroirs were associated with high nitrogenous compounds content, high expansion volume and low density of roasted coffees, and the beverages showed a high turbidity and intense body. Apucarana, São Jerônimo da Serra and Ribeirão do Pinhal terroirs were associated with low lipids content, high density and low volume expansion roasted coffee, and the beverage showed intense coffee and sweet aromas and a low turbidity and body texture. In coffee from the Londrina terroir, medium nitrogenous compounds content and high sucrose and lipids contents were found. Their beverage showed a high turbidity and intense body as well as a grassy green taste and astringency. Coffee from Ribeirão Claro terroir presented high lipids and sucrose contents and low caffeine and phenolic compounds contents, and the main sensory attributes were a coffee aroma and sweet and sour tastes. In conclusion, a terroir formed by environmental conditions and agricultural techniques can produce coffee with a set of physico-chemical and sensory characteristics that define its typicity.


Asunto(s)
Coffea/química , Café/química , Café/clasificación , Brasil , Cafeína/análisis , Fenómenos Químicos , Análisis Factorial , Análisis de los Alimentos , Manipulación de Alimentos , Calor , Odorantes/análisis , Fenoles/análisis
7.
Food Res Int ; 108: 280-285, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29735059

RESUMEN

The results found in the literature concerning the effect of consuming filter coffee brews on increasing the blood cholesterol levels due to the presence of diterpenes, are divergent. Thus the present research evaluated the diterpene (cafestol and kahweol) concentrations in filter coffee brews prepared with paper filters of different sizes, colors and origins (Brazil, Japan, The United States of America, Germany, France and the Netherlands), with and without micro perforations. This is the first study that reports the physical characteristics of paper filter and its importance to obtain filter coffee brew with low cafestol content. Thus, a sample of Catuai cultivar coffee with high cafestol content was roasted to a medium-light degree and used to prepare the brews in a 1:10 ratio (coffee powder to water). The diterpenes were extracted by direct saponification and quantified and identified by HPLC-DAD-MS/MS. The paper filters were physically characterized by measuring their grammage, and the fat permeation rate calculated in order to better understand the differences between the filters which allow one to obtain higher or lower diterpene contents. The cafestol and kahweol concentrations in the brews varied from 1.62 to 2.98 mg/L and from 0.73 to 1.96 mg/L, respectively. The highest cafestol and kahweol concentrations were obtained using paper filters with micro perforations, considering similar sized paper filters. The paper filters showed high fat permeability and grammages between 50.46 and 67.48 g/m2. The diterpene retention capacities of the filters produced in the different countries were similar. The results showed that the porosity of the paper filter and the particle size of the ground roasted coffee were determinant factors in obtaining filter coffee brews with lower cafestol contents.


Asunto(s)
Café/química , Culinaria/instrumentación , Diterpenos/análisis , Filtración/instrumentación , Papel , Cromatografía Líquida de Alta Presión , Culinaria/métodos , Diseño de Equipo , Análisis de los Alimentos/métodos , Calor , Tamaño de la Partícula , Permeabilidad , Porosidad , Espectrometría de Masas en Tándem
8.
Sci Rep ; 8(1): 465, 2018 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-29323254

RESUMEN

Lipids, including the diterpenes cafestol and kahweol, are key compounds that contribute to the quality of coffee beverages. We determined total lipid content and cafestol and kahweol concentrations in green beans and genotyped 107 Coffea arabica accessions, including wild genotypes from the historical FAO collection from Ethiopia. A genome-wide association study was performed to identify genomic regions associated with lipid, cafestol and kahweol contents and cafestol/kahweol ratio. Using the diploid Coffea canephora genome as a reference, we identified 6,696 SNPs. Population structure analyses suggested the presence of two to three groups (K = 2 and K = 3) corresponding to the east and west sides of the Great Rift Valley and an additional group formed by wild accessions collected in western forests. We identified 5 SNPs associated with lipid content, 4 with cafestol, 3 with kahweol and 9 with cafestol/kahweol ratio. Most of these SNPs are located inside or near candidate genes related to metabolic pathways of these chemical compounds in coffee beans. In addition, three trait-associated SNPs showed evidence of directional selection among cultivated and wild coffee accessions. Our results also confirm a great allelic richness in wild accessions from Ethiopia, especially in accessions originating from forests in the west side of the Great Rift Valley.


Asunto(s)
Coffea/química , Diterpenos/análisis , Estudio de Asociación del Genoma Completo/métodos , Polimorfismo de Nucleótido Simple , Vías Biosintéticas , Coffea/genética , Diterpenos/metabolismo , Lípidos/análisis , Lípidos/biosíntesis , Proteínas de Plantas/genética , Sitios de Carácter Cuantitativo , Análisis de Secuencia de ADN/métodos
9.
Food Res Int ; 100(Pt 1): 798-803, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28873752

RESUMEN

Coffee brew presents sensory, stimulatory and antioxidant properties highly appreciated by consumers, despite being associated with an increase in the level of blood cholesterol due to the effects of the diterpenes, especially cafestol, present in the lipid fraction. Although it is believed that the paper filter retains the brew diterpenes, new studies have shown that sometimes coffee filtered through paper can also increase the blood cholesterol level, putting in doubt the efficiency of the paper filter in retaining the diterpenes. Thus the objective of the present study was to verify the distribution of cafestol between the paper filter, the spent coffee and the coffee brew itself, from two coffee samples containing high and low cafestol contents selected from 13 samples of different cultivars and from different locations. In addition, the effect of the roasting degree on the cafestol contents of the roasted coffee was evaluated and the relationship between particle size of the roasted coffee and the extraction of solids. The highest cafestol content was found in the lightly roasted coffee, and the coffee brew presented higher solids contents when the particle size of the coffee powder was below 500µm. The results showed that of the initial cafestol concentration present in the roasted coffee, the paper filter retained 12.41%, the spent coffee 87.45% and the brew 0.15%. Thus, one can conclude that the greater part of the coffee cafestol is retained by the spent coffee, due to the low extraction of the lipid fraction by the hot water.


Asunto(s)
Café/química , Culinaria/métodos , Diterpenos/análisis , Culinaria/instrumentación , Diterpenos/química , Espectrometría de Masas , Papel , Tamaño de la Partícula , Temperatura
10.
Plant Physiol Biochem ; 111: 340-347, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28002787

RESUMEN

Lipids are among the major chemical compounds present in coffee beans, and they affect the flavor and aroma of the coffee beverage. Coffee oil is rich in kaurene diterpene compounds, mainly cafestol (CAF) and kahweol (KAH), which are related to plant defense mechanisms and to nutraceutical and sensorial beverage characteristics. Despite their importance, the final steps of coffee diterpenes biosynthesis remain unknown. To understand the molecular basis of coffee diterpenes biosynthesis, we report the content dynamics of CAF and KAH in several Coffea arabica tissues and the transcriptional analysis of cytochrome P450 genes (P450). We measured CAF and KAH concentrations in leaves, roots, flower buds, flowers and fruit tissues at seven developmental stages (30-240 days after flowering - DAF) using HPLC. Higher CAF levels were detected in flower buds and flowers when compared to fruits. In contrast, KAH concentration increased along fruit development, peaking at 120 DAF. We did not detect CAF or KAH in leaves, and higher amounts of KAH than CAF were detected in roots. Using P450 candidate genes from a coffee EST database, we performed RT-qPCR transcriptional analysis of leaves, flowers and fruits at three developmental stages (90, 120 and 150 DAF). Three P450 genes (CaCYP76C4, CaCYP82C2 and CaCYP74A1) had transcriptional patterns similar to CAF concentration and two P450 genes (CaCYP71A25 and CaCYP701A3) have transcript accumulation similar to KAH concentration. These data warrant further investigation of these P450s as potential candidate genes involved in the final stages of the CAF and KAH biosynthetic pathways.


Asunto(s)
Coffea/genética , Sistema Enzimático del Citocromo P-450/genética , Diterpenos/metabolismo , Flores/enzimología , Frutas/crecimiento & desarrollo , Hojas de la Planta/enzimología , Raíces de Plantas/enzimología , Transcripción Genética , Cromatografía Líquida de Alta Presión , Coffea/crecimiento & desarrollo , Diterpenos/análisis , Flores/genética , Frutas/genética , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Estudios de Asociación Genética , Hojas de la Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/genética
11.
Bol. Centro Pesqui. Process. Aliment ; 31(01): 161-172, jan. 2013.
Artículo en Portugués | LILACS | ID: biblio-986359

RESUMEN

O presente trabalho refere-se à pesquisa de dois cafés exóticos comercializados no Brasil: o café Jacu, proveniente do estado de Espírito Santo, e o café Civeta procedente da Indonésia (cujos frutos maduros são ingeridos e "processados" no trato digestivo de animais). Suas características químicas e físicas foram comparadas às de cafés torrados e moídos comerciais brasileiros (Tradicional, Superior ou Premium e Gourmet). Os valores referentes à composição centesimal, teor de cafeína (1,04 a 1,45%) e sólidos solúveis totais (24,50 a 32,23%) de todas as amostras atenderam aos limites preconizados pela legislação brasileira. Os cafés exóticos, Jacu e Civeta, apresentaram os maiores e menores parâmetros de cor, respectivamente (L* = 20,46 e 11,55; h* = 58,13 e 51,06 e C* = 21,00 e 14,85). Os maiores teores (média de 35,21 mg em equivalente de ácido gálico/g amostra) de compostos fenólicos totais foram verificados nos cafés Tradicional e Premium. Os cafés Jacu e Gourmet apresentaram os maiores teores de 5-ACQ (média de 0,65%) e de trigonelina (média 0,63 g/100 g amostra) e os menores teores de ácido nicotínico (média de 0,022 g/100 g amostra). O café Premium continha os maiores teores de açúcar total (1,37 g glicose/100 g amostra) e o café Tradicional mostrou o maior teor de açúcares redutores (0,27 g sacarose/100 g amostra). O café Gourmet apresentou a maior acidez titulável total (171,13 mL NaOH 0,1 N/100 g amostra) e o Premium a menor (121,31 mL NaOH 0,1 N/100 g amostra).


Asunto(s)
Café/clasificación , Café/química , Compuestos Fenólicos
12.
Plant Physiol Biochem ; 46(5-6): 569-79, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18420417

RESUMEN

Coffee fruits grown in shade are characterized by larger bean size than those grown under full-sun conditions. The present study assessed the effects of shade on bean characteristics and sugar metabolism by analyzing tissue development, sugar contents, activities of sucrose metabolizing enzymes and expression of sucrose synthase-encoding genes in fruits of coffee (Coffea arabica L.) plants submitted to full-sun (FS) and shade (SH) conditions. Evolution of tissue fresh weights measured in fruits collected regularly from flowering to maturation indicated that this increase is due to greater development of the perisperm tissue in the shade. The effects of light regime on sucrose and reducing sugar (glucose and fructose) contents were studied in fresh and dry coffee beans. Shade led to a significant reduction in sucrose content and to an increase in reducing sugars. In pericarp and perisperm tissues, higher activities of sucrose synthase (EC 2.4.1.13) and sucrose-phosphate synthase (SPS: EC 2.4.1.14) were detected at maturation in the shade compared with full sun. These two enzymes also had higher peaks of activities in developing endosperm under shade than in full sun. It was also noted that shade modified the expression of SUS-encoding genes in coffee beans; CaSUS2 gene transcripts levels were higher in SH than in FS. As no sucrose increase accompanied these changes, this suggests that sucrose metabolism was redirected to other metabolic pathways that need to be identified.


Asunto(s)
Coffea/crecimiento & desarrollo , Coffea/metabolismo , Frutas/crecimiento & desarrollo , Frutas/metabolismo , Northern Blotting , Metabolismo de los Hidratos de Carbono/efectos de la radiación , Coffea/genética , Frutas/genética , Regulación del Desarrollo de la Expresión Génica/efectos de la radiación , Regulación de la Expresión Génica de las Plantas/efectos de la radiación , Glucosiltransferasas/genética , Glucosiltransferasas/metabolismo , Luz
13.
Semina ciênc. agrar ; 29(2): 331-338, 2008.
Artículo en Portugués | LILACS-Express | VETINDEX | ID: biblio-1498373

RESUMEN

The Brazilian coffee production plays important role both in the national and oversea trade. The quality and sanity of coffee depend on fungal contamination, with emphasis on ochratoxin A (OTA) producing species, which is a nephrotoxin with hazardous effect in public health. The exigency on continuous monitoring and control of OTA in agricultural commodity requires a simple, rapid and accessible analytical methodology. The objective of this research was to set up the spectrofluorimetric method for OTA detection intended for monitoring in coffee, which was developed in data-correlation with high efficiency liquid chromatography (HPLC). The performance of spectrofluorimetric analysis was evaluated using artificially contaminated coffee (10, 20 and 50 ng/g), and the data compared with HPLC. Although of the fault of former technique, with recovery of 40.14 % and correlation coefficient of 0.79 when compared to HPLC, i.e. low reliability and inadequate efficiency, the data showed perspective to follow the improvement inserting new tool, and further standardization and certification.


A cafeicultura brasileira apresenta grande importância ao mercado interno e comércio exterior. A qualidade e sanidade do café dependem da contaminação fúngica, com ênfase as espécies produtoras de ocratoxina A (OTA), uma nefrotoxina de efeito deletério à saúde pública. A necessidade de contínuo monitoramento e controle de OTA em produtos agrícolas requer metodologia analítica simples, rápida e acessível. O trabalho teve como objetivo padronizar um método espectrofluorimétrico para detecção de OTA visando monitoramento em grãos de café, correlacionando-o com a cromatografia líquida de alta eficiência (CLAE). A aplicabilidade da espectrofluorimetria foi avaliada em café artificialmente contaminado com OTA (10, 20 e 50 ng/g), comparando os resultados obtidos com a CLAE. Embora a fluorimetria tenha apresentado resultados insatisfatórios, com recuperação de 40,14 % e coeficiente de correlação de 0,79 em relação a CLAE, i.e. baixa confiabilidade e eficiência inadequada, a técnica constitui perspectiva para prosseguir o estudo inserindo novos ensaios referentes à sua padronização e certificação.

14.
Semina Ci. agr. ; 29(2): 331-338, 2008.
Artículo en Portugués | VETINDEX | ID: vti-471362

RESUMEN

The Brazilian coffee production plays important role both in the national and oversea trade. The quality and sanity of coffee depend on fungal contamination, with emphasis on ochratoxin A (OTA) producing species, which is a nephrotoxin with hazardous effect in public health. The exigency on continuous monitoring and control of OTA in agricultural commodity requires a simple, rapid and accessible analytical methodology. The objective of this research was to set up the spectrofluorimetric method for OTA detection intended for monitoring in coffee, which was developed in data-correlation with high efficiency liquid chromatography (HPLC). The performance of spectrofluorimetric analysis was evaluated using artificially contaminated coffee (10, 20 and 50 ng/g), and the data compared with HPLC. Although of the fault of former technique, with recovery of 40.14 % and correlation coefficient of 0.79 when compared to HPLC, i.e. low reliability and inadequate efficiency, the data showed perspective to follow the improvement inserting new tool, and further standardization and certification.


A cafeicultura brasileira apresenta grande importância ao mercado interno e comércio exterior. A qualidade e sanidade do café dependem da contaminação fúngica, com ênfase as espécies produtoras de ocratoxina A (OTA), uma nefrotoxina de efeito deletério à saúde pública. A necessidade de contínuo monitoramento e controle de OTA em produtos agrícolas requer metodologia analítica simples, rápida e acessível. O trabalho teve como objetivo padronizar um método espectrofluorimétrico para detecção de OTA visando monitoramento em grãos de café, correlacionando-o com a cromatografia líquida de alta eficiência (CLAE). A aplicabilidade da espectrofluorimetria foi avaliada em café artificialmente contaminado com OTA (10, 20 e 50 ng/g), comparando os resultados obtidos com a CLAE. Embora a fluorimetria tenha apresentado resultados insatisfatórios, com recuperação de 40,14 % e coeficiente de correlação de 0,79 em relação a CLAE, i.e. baixa confiabilidade e eficiência inadequada, a técnica constitui perspectiva para prosseguir o estudo inserindo novos ensaios referentes à sua padronização e certificação.

15.
Food Addit Contam ; 23(9): 902-9, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16901859

RESUMEN

The performance of an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) based on a monoclonal antibody (mAb) for ochratoxin A (OTA) detection was evaluated in a comparative study with high-performance liquid chromatography (HPLC) analysis using 68 freshly harvested coffee samples from the North of Paraná State, Brazil. The anti-OTA mAb showed high specificity and low cross-reactivity with OTA analogues (OTB and OTalpha), but cross-reacted with OTC. This ic-ELISA showed a detection limit of 3.75 ngg-1 sample, when compared to 0.80 ngg-1 by HPLC, with an ic-ELISA/HPLC correlation coefficient of 0.90. As regards OTA analysis of these coffee samples, natural contamination was detected in 10 samples (14.7%) by both methods, where the ic-ELISA values (range 3.9-7.3 ngg-1) were 1.1 to 1.6-fold higher than HPLC data (2.7-4.7 ngg-1). Five samples (7.4%) were OTA positive (range 0.84-1.30 ngg-1) only by HPLC assay, probably due to the higher detection limit reached by ic-ELISA. OTA was undetectable in 53 samples (77.9%) by both methods, while all positive samples (range 0.84-7.30 ngg-1) showed OTA levels lower than 8 ngg-1 (maximum limit recommended by the European Union). The matrix interference of green coffee was minimized by dilution of sample extracts before carrying out the ELISA assay. This mAb-based ic-ELISA can be effectively applied for OTA screening in coffee, because it is simple, sensitive and sample preparation is easy.


Asunto(s)
Café/química , Ensayo de Inmunoadsorción Enzimática/métodos , Contaminación de Alimentos/análisis , Ocratoxinas/análisis , Anticuerpos Monoclonales/inmunología , Carcinógenos/análisis , Cromatografía Líquida de Alta Presión/métodos , Análisis de los Alimentos/métodos , Humanos , Micotoxinas/análisis , Ocratoxinas/inmunología , Reproducibilidad de los Resultados
16.
Sci. agric ; 63(3)2006.
Artículo en Inglés | LILACS-Express | VETINDEX | ID: biblio-1496637

RESUMEN

The effect of thermal summation on orange fruit growth on different rootstocks has not been studied for the State of Paraná, Brazil. This research evaluated the growth of fruits by means of maturation curves, and quantified the growing degree-days (GDD) accumulation required for fruit maturation in 'Folha Murcha' orange trees budded on 'Rangpur' lime, 'Volkamer' lemon, 'Sunki' mandarin, and 'Cleopatra' mandarin, in Paranavaí and Londrina, PR. In both locations and all rootstocks, the fruits showed evolution in total soluble solids (TSS) content in relation to GDD accumulation, with a quadratic tendency of curve fitting; total titratable acidity (TTA) had an inverse quadratic fitting, and the (TSS/TTA) ratio showed a positive linear regression. Fruits in Paranavaí presented a higher development rate towards maturity than those in Londrina, for all rootstocks. The advancing of the initial maturation stage of fruits in Paranavaí in relation to those in Londrina occurred in the following descending order: 'Volkamer' lemon (92 days), 'Cleopatra' mandarin (81 days), 'Sunki' mandarin (79 days), 'Rangpur' lime (77 days). In Londrina, trees on 'Rangpur' lime and 'Volkamer' lemon were ready for harvest 8 and 15 days before those on the 'Cleopatra' and 'Sunki' mandarins, respectively. In Paranavaí, the beginning of fruit maturation in trees on 'Volkamer' lemon occurred 15, 19, and 28 days earlier than on 'Rangpur' lime, 'Cleopatra' mandarin, and 'Sunki' mandarin, respectively. Considering 12.8ºC as the lower base temperature, the thermal sum for fruit growth and maturation of 'Folha Murcha' orange ranged from 4,462 to 5,090 GDD.


O efeito da soma térmica no crescimento do fruto de laranja em diferentes porta-enxertos não tem sido estudado no Estado do Paraná, Brasil. Esta pesquisa avaliou o crescimento dos frutos por meio de curvas de maturação e quantificou os graus-dia acumulados (GDA) necessários para a maturação dos frutos em laranjeiras 'Folha Murcha' enxertadas em limão 'Cravo', limão 'Volcameriano', tangerina 'Sunki' e tangerina 'Cleópatra', em Paranavaí e Londrina, PR. Para os dois locais e em todos os porta-enxertos, os frutos apresentaram evolução do teor de sólidos solúveis totais (SST) em relação ao acúmulo de graus-dia com ajuste de tendência quadrática da curva de regressão; a acidez titulável total (ATT) com ajuste quadrático inverso e o ratio (SST/ATT) regressão linear positiva. Os frutos em Paranavaí apresentaram maior índice de maturação do que em Londrina para todos os porta-enxertos, com antecipação do ponto inicial de maturação na seguinte ordem: limão 'Volcameriano' (92 dias), tangerina 'Cleópatra' (81 dias), tangerina 'Sunki' (79 dias), limão 'Cravo' (77 dias). Em Londrina, as plantas sobre os limões 'Cravo' e 'Volcameriano' apresentaram início da colheita 8 e 15 dias antes daquelas nas tangerinas 'Cleópatra' e 'Sunki', respectivamente. Em Paranavaí, o início da maturação dos frutos das plantas em limão 'Volcameriano' ocorreu 15, 19 e 28 dias mais precoce que o limão 'Cravo', tangerina 'Cleópatra' e tangerina 'Sunki', respectivamente. A soma térmica para o crescimento e maturação dos frutos de laranja 'Folha Murcha' variou de 4.462 a 5.090 GDA.

17.
Sci. agric. ; 63(3)2006.
Artículo en Inglés | VETINDEX | ID: vti-440064

RESUMEN

The effect of thermal summation on orange fruit growth on different rootstocks has not been studied for the State of Paraná, Brazil. This research evaluated the growth of fruits by means of maturation curves, and quantified the growing degree-days (GDD) accumulation required for fruit maturation in 'Folha Murcha' orange trees budded on 'Rangpur' lime, 'Volkamer' lemon, 'Sunki' mandarin, and 'Cleopatra' mandarin, in Paranavaí and Londrina, PR. In both locations and all rootstocks, the fruits showed evolution in total soluble solids (TSS) content in relation to GDD accumulation, with a quadratic tendency of curve fitting; total titratable acidity (TTA) had an inverse quadratic fitting, and the (TSS/TTA) ratio showed a positive linear regression. Fruits in Paranavaí presented a higher development rate towards maturity than those in Londrina, for all rootstocks. The advancing of the initial maturation stage of fruits in Paranavaí in relation to those in Londrina occurred in the following descending order: 'Volkamer' lemon (92 days), 'Cleopatra' mandarin (81 days), 'Sunki' mandarin (79 days), 'Rangpur' lime (77 days). In Londrina, trees on 'Rangpur' lime and 'Volkamer' lemon were ready for harvest 8 and 15 days before those on the 'Cleopatra' and 'Sunki' mandarins, respectively. In Paranavaí, the beginning of fruit maturation in trees on 'Volkamer' lemon occurred 15, 19, and 28 days earlier than on 'Rangpur' lime, 'Cleopatra' mandarin, and 'Sunki' mandarin, respectively. Considering 12.8ºC as the lower base temperature, the thermal sum for fruit growth and maturation of 'Folha Murcha' orange ranged from 4,462 to 5,090 GDD.


O efeito da soma térmica no crescimento do fruto de laranja em diferentes porta-enxertos não tem sido estudado no Estado do Paraná, Brasil. Esta pesquisa avaliou o crescimento dos frutos por meio de curvas de maturação e quantificou os graus-dia acumulados (GDA) necessários para a maturação dos frutos em laranjeiras 'Folha Murcha' enxertadas em limão 'Cravo', limão 'Volcameriano', tangerina 'Sunki' e tangerina 'Cleópatra', em Paranavaí e Londrina, PR. Para os dois locais e em todos os porta-enxertos, os frutos apresentaram evolução do teor de sólidos solúveis totais (SST) em relação ao acúmulo de graus-dia com ajuste de tendência quadrática da curva de regressão; a acidez titulável total (ATT) com ajuste quadrático inverso e o ratio (SST/ATT) regressão linear positiva. Os frutos em Paranavaí apresentaram maior índice de maturação do que em Londrina para todos os porta-enxertos, com antecipação do ponto inicial de maturação na seguinte ordem: limão 'Volcameriano' (92 dias), tangerina 'Cleópatra' (81 dias), tangerina 'Sunki' (79 dias), limão 'Cravo' (77 dias). Em Londrina, as plantas sobre os limões 'Cravo' e 'Volcameriano' apresentaram início da colheita 8 e 15 dias antes daquelas nas tangerinas 'Cleópatra' e 'Sunki', respectivamente. Em Paranavaí, o início da maturação dos frutos das plantas em limão 'Volcameriano' ocorreu 15, 19 e 28 dias mais precoce que o limão 'Cravo', tangerina 'Cleópatra' e tangerina 'Sunki', respectivamente. A soma térmica para o crescimento e maturação dos frutos de laranja 'Folha Murcha' variou de 4.462 a 5.090 GDA.

18.
Ciênc. rural ; Ciênc. rural (Online);35(6): 1281-1286, nov.-dez. 2005. tab
Artículo en Portugués | LILACS | ID: lil-417664

RESUMEN

Esta pesquisa avaliou em Londrina, PR, plantas de laranjeira 'Folha Murcha' sobre os porta-enxertos: laranjeira 'Caipira' (Citrus sinensis (L.) Osb.), limoeiro 'Cravo' (Citrus limonia Osb.), tangerineira 'Sunki' (Citrus sunki Hort. ex Tan.), limoeiro 'Rugoso da Flórida (Citrus jambhiri Lush.), tangerineira 'Cleópatra' (Citrus reshni Hort. ex Tan.) e limoeiro 'Volcameriano' (Citrus volkameriana Ten. e Pasq.). O delineamento experimental utilizado foi o de blocos ao acaso, seis porta-enxertos como tratamentos, cinco repetições e duas plantas por parcela. A altura, diâmetro e volume da copa foram significativamente superiores em plantas enxertadas em laranjeira 'Caipira', quando comparadas com aquelas em limoeiro 'Volcameriano'. A menor diferença entre os diâmetros dos troncos abaixo/acima da enxertia ocorreu nas plantas em limoeiro 'Cravo' e tangerineira 'Sunki'. A produção acumulada foi superior nas plantas sobre limoeiro 'Cravo'e laranjeira 'Caipira', sem mostrar significância estatística entre si, porém significativamente diferentes daquelas sobre tangerineira 'Cleópatra' e limoeiro 'Volcameriano'. A eficiência da produção não foi influenciada pelos porta-enxertos estudados. O peso do fruto foi significativamente maior para as plantas em tangerineira 'Sunki', em comparação àqueles sobre limoeiros 'Cravo', limoeiro 'Rugoso da Flórida' e limoeiro vVolcameriano. Os sólidos solúveis totais (SST) apresentaram teores elevados nos frutos de laranjeiras 'Folha Murcha' sobre limoeiro æVolcameriano' e limoeiro 'Cravo', sem diferirem entre si. A acidez titulável total (ATT), o ratio (SST/ATT) e a cor do suco não foram influenciados pelos porta-enxertos testados. Os limões 'Cravo'e 'Volcameriano' proporcionaram valores de índice tecnológico significativamente maiores em relação aos porta-enxertos restantes. Os parâmetros de qualidade de suco avaliados estão dentro de padrões aceitáveis para variedades copa de laranja.


Asunto(s)
Citrus sinensis , Frutas , Plantas
19.
Artículo en Portugués | LILACS-Express | VETINDEX | ID: biblio-1476608

RESUMEN

This research evaluated, in Londrina, PR, Brazil, ‘Folha Murcha' orange trees on the rootstocks: ‘Caipira' orange (Citrus sinensis (L.) Osb.), ‘Rangpur' lime (Citrus limonia Osb.), ‘Sunki' mandarin (Citrus sunki Hort. ex Tan.), ‘Florida' rough lemon (Citrus jambhiri Lush.), ‘Cleopatra' mandarin (Citrus reshni Hort. ex Tan.), and ‘Volkamer' lemon (Citrus volkameriana Ten. & Pasq.). The experimental design was used as randomized blocks with six rootstocks as treatments, five replications and three plants per plot. Height, diameter, and canopy volume were significantly higher in trees budded on ‘Caipira' orange, when compared with those budded on ‘Volkamer' lemon. The smallest difference between trunk diameters below/above the bud occurred in trees on ‘Rangpur' lime and ‘Sunki' mandarin. Cumulative yield was superior for trees on ‘Rangpur' lime and ‘Caipira' orange, without showing statistical difference between themselves, but were significantly different from those on ‘Cleopatra' mandarin and ‘Volkamer' lemon. Yield efficiency was not influenced by the studied rootstocks. Fruit weight was significantly higher for trees on ‘Sunki' mandarin, compared to those on ‘Rangpur' lime, ‘Florida' rough lemon, and ‘Volkamer' lemon. Total soluble solids (TSS) showed high contents in fruits of ‘Folha Murcha' orange on ‘Volkamer' lemon and on ‘Rangpur' lime, without differences between themselves. Total titratable acidity (TTA), (TSS/TTA) ratio, and juice color were not influenced by the rootstocks tested. ‘Rangpur' lime and ‘Volkamer' lemon provided significantly higher technological index values in relation to the other rootstocks. The juice quality parameters evaluated were within the acceptable standards for orange canopy varieties.


Esta pesquisa avaliou em Londrina, PR, plantas de laranjeira ‘Folha Murcha' sobre os porta-enxertos: laranjeira ‘Caipira' (Citrus sinensis (L.) Osb.), limoeiro ‘Cravo' (Citrus limonia Osb.), tangerineira ‘Sunki' (Citrus sunki Hort. ex Tan.), limoeiro ‘Rugoso da Flórida (Citrus jambhiri Lush.), tangerineira ‘Cleópatra' (Citrus reshni Hort. ex Tan.) e limoeiro ‘Volcameriano' (Citrus volkameriana Ten. e Pasq.). O delineamento experimental utilizado foi o de blocos ao acaso, seis porta-enxertos como tratamentos, cinco repetições e duas plantas por parcela. A altura, diâmetro e volume da copa foram significativamente superiores em plantas enxertadas em laranjeira ‘Caipira', quando comparadas com aquelas em limoeiro ‘Volcameriano'. A menor diferença entre os diâmetros dos troncos abaixo/acima da enxertia ocorreu nas plantas em limoeiro ‘Cravo' e tangerineira ‘Sunki'. A produção acumulada foi superior nas plantas sobre limoeiro 'Cravo'e laranjeira ‘Caipira', sem mostrar significância estatística entre si, porém significativamente diferentes daquelas sobre tangerineira ‘Cleópatra' e limoeiro ‘Volcameriano'. A eficiência da produção não foi influenciada pelos porta-enxertos estudados. O peso do fruto foi significativamente maior para as plantas em tangerineira ‘Sunki', em comparação àqueles sobre limoeiros ‘Cravo', limoeiro ‘Rugoso da Flórida' e limoeiro ‘Volcameriano. Os sólidos solúveis totais (SST) apresentaram teores elevados nos frutos de laranjeiras ‘Folha Murcha' sobre limoeiro ‘Volcameriano' e limoeiro 'Cravo', sem diferirem entre si. A acidez titulável total (ATT), o ratio (SST/ATT) e a cor do suco não foram influenciados pelos porta-enxertos testados. Os limões 'Cravo'e ‘Volcameriano' proporcionaram valores de índice tecnológico significativamente maiores em relação aos porta-enxertos restantes. Os parâmetros de qualidade de suco avaliados estão dentro de padrões aceitáveis para variedades copa de laranja.

20.
Ci. Rural ; 35(6)2005.
Artículo en Portugués | VETINDEX | ID: vti-704823

RESUMEN

This research evaluated, in Londrina, PR, Brazil, ‘Folha Murcha' orange trees on the rootstocks: ‘Caipira' orange (Citrus sinensis (L.) Osb.), ‘Rangpur' lime (Citrus limonia Osb.), ‘Sunki' mandarin (Citrus sunki Hort. ex Tan.), ‘Florida' rough lemon (Citrus jambhiri Lush.), ‘Cleopatra' mandarin (Citrus reshni Hort. ex Tan.), and ‘Volkamer' lemon (Citrus volkameriana Ten. & Pasq.). The experimental design was used as randomized blocks with six rootstocks as treatments, five replications and three plants per plot. Height, diameter, and canopy volume were significantly higher in trees budded on ‘Caipira' orange, when compared with those budded on ‘Volkamer' lemon. The smallest difference between trunk diameters below/above the bud occurred in trees on ‘Rangpur' lime and ‘Sunki' mandarin. Cumulative yield was superior for trees on ‘Rangpur' lime and ‘Caipira' orange, without showing statistical difference between themselves, but were significantly different from those on ‘Cleopatra' mandarin and ‘Volkamer' lemon. Yield efficiency was not influenced by the studied rootstocks. Fruit weight was significantly higher for trees on ‘Sunki' mandarin, compared to those on ‘Rangpur' lime, ‘Florida' rough lemon, and ‘Volkamer' lemon. Total soluble solids (TSS) showed high contents in fruits of ‘Folha Murcha' orange on ‘Volkamer' lemon and on ‘Rangpur' lime, without differences between themselves. Total titratable acidity (TTA), (TSS/TTA) ratio, and juice color were not influenced by the rootstocks tested. ‘Rangpur' lime and ‘Volkamer' lemon provided significantly higher technological index values in relation to the other rootstocks. The juice quality parameters evaluated were within the acceptable standards for orange canopy varieties.


Esta pesquisa avaliou em Londrina, PR, plantas de laranjeira ‘Folha Murcha' sobre os porta-enxertos: laranjeira ‘Caipira' (Citrus sinensis (L.) Osb.), limoeiro ‘Cravo' (Citrus limonia Osb.), tangerineira ‘Sunki' (Citrus sunki Hort. ex Tan.), limoeiro ‘Rugoso da Flórida (Citrus jambhiri Lush.), tangerineira ‘Cleópatra' (Citrus reshni Hort. ex Tan.) e limoeiro ‘Volcameriano' (Citrus volkameriana Ten. e Pasq.). O delineamento experimental utilizado foi o de blocos ao acaso, seis porta-enxertos como tratamentos, cinco repetições e duas plantas por parcela. A altura, diâmetro e volume da copa foram significativamente superiores em plantas enxertadas em laranjeira ‘Caipira', quando comparadas com aquelas em limoeiro ‘Volcameriano'. A menor diferença entre os diâmetros dos troncos abaixo/acima da enxertia ocorreu nas plantas em limoeiro ‘Cravo' e tangerineira ‘Sunki'. A produção acumulada foi superior nas plantas sobre limoeiro 'Cravo'e laranjeira ‘Caipira', sem mostrar significância estatística entre si, porém significativamente diferentes daquelas sobre tangerineira ‘Cleópatra' e limoeiro ‘Volcameriano'. A eficiência da produção não foi influenciada pelos porta-enxertos estudados. O peso do fruto foi significativamente maior para as plantas em tangerineira ‘Sunki', em comparação àqueles sobre limoeiros ‘Cravo', limoeiro ‘Rugoso da Flórida' e limoeiro ‘Volcameriano. Os sólidos solúveis totais (SST) apresentaram teores elevados nos frutos de laranjeiras ‘Folha Murcha' sobre limoeiro ‘Volcameriano' e limoeiro 'Cravo', sem diferirem entre si. A acidez titulável total (ATT), o ratio (SST/ATT) e a cor do suco não foram influenciados pelos porta-enxertos testados. Os limões 'Cravo'e ‘Volcameriano' proporcionaram valores de índice tecnológico significativamente maiores em relação aos porta-enxertos restantes. Os parâmetros de qualidade de suco avaliados estão dentro de padrões aceitáveis para variedades copa de laranja.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA