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1.
Food Res Int ; 114: 72-80, 2018 12.
Article in English | MEDLINE | ID: mdl-30361029

ABSTRACT

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.


Subject(s)
Coffea/chemistry , Coffee/chemistry , Coffee/classification , Brazil , Caffeine/analysis , Chemical Phenomena , Factor Analysis, Statistical , Food Analysis , Food Handling , Hot Temperature , Odorants/analysis , Phenols/analysis
2.
Acta sci., Biol. sci ; 37(4): 411-417, Oct.-Dec. 2015. tab, ilus
Article in English | LILACS | ID: biblio-876365

ABSTRACT

The production of hyaluronic acid by Streptococcus zooepidemicus ATCC 39920 with varying rates of pH (6.0, 7.0, 8.0), temperature (34; 37; 40°C), agitation (100, 150, 200 rpm), glucose (10, 20, 30 g L -1) and yeast extract concentration (10, 20, 30 g L -1) was evaluated by statistical approaches. The best conditions for the production of hyaluronic acid was pH 8.0, 37°C and 100 rpm in a medium containing 30 g L- 1 glucose and yeast extract, for a production of 0.787 g L- 1. Temperature, pH and yeast extract were significant variables (p < 0.05). Yeast extract and pH had a positive effect on the production of the polymer. Lactate, formate and acetate synthesis were also analyzed. Current assay showed the feasibility of statistical tools to optimize the physical and nutritional parameters for the production of hyaluronic acid and the improvement of the fermentation process.


A produção de ácido hialurônico por Streptococcus zooepidemicus ATCC 39920 foi avaliada variando pH (6,0; 7,0, 8,0), temperatura (34; 37; 40°C), agitação (100, 150, 200 rpm) e concentração de glicose (10, 20, 30 g L-1) e extrato de levedura (10, 20, 30 g L-1) por metodologias estatísticas. A condição otimizada foi pH 8,0, 37°C e 100 rpm, em meio contendo 30 g L-1 de glicose e extrato de levedura atingindo a produção de 0,787 g L-1. O pH, temperatura e extrato de levedura foram as variáveis significativas (p < 0,05). Extrato de levedura e pH apresentaram efeito positivo para a produção do polímero. A síntese de ácido lático, fórmico e acético também foi analisada. Este estudo demonstra a viabilidade de utilização de ferramentas estatísticas para otimizar os parâmetros físicos e nutricionais para a produção de ácido hialurônico, permitindo a melhoria do processo fermentativo.


Subject(s)
Glycosaminoglycans , Hyaluronic Acid , Microbial Interactions , Nutritional Physiological Phenomena
3.
Acta Sci. Biol. Sci. ; 37(4): 411-417, 20150000. ilus, tab
Article in English | VETINDEX | ID: vti-334126

ABSTRACT

The production of hyaluronic acid by Streptococcus zooepidemicus ATCC 39920 with varying rates of pH (6.0, 7.0, 8.0), temperature (34; 37; 40°C), agitation (100, 150, 200 rpm), glucose (10, 20, 30 g L-1) and yeast extract concentration (10, 20, 30 g L-1) was evaluated by statistical approaches. The best conditions for the production of hyaluronic acid was pH 8.0, 37°C and 100 rpm in a medium containing 30 g L-1 glucose and yeast extract, for a production of 0.787 g L-1. Temperature, pH and yeast extract were significant variables (p 0.05). Yeast extract and pH had a positive effect on the production of the polymer. Lactate, formate and acetate synthesis were also analyzed. Current assay showed the feasibility of statistical tools to optimize the physical and nutritional parameters for the production of hyaluronic acid and the improvement of the fermentation process.(AU)


A produção de ácido hialurônico por Streptococcus zooepidemicus ATCC 39920 foi avaliada variando pH (6,0; 7,0, 8,0), temperatura (34; 37; 40°C), agitação (100, 150, 200 rpm) e concentração de glicose (10, 20, 30 g L-1) e extrato de levedura (10, 20, 30 g L-1) por metodologias estatísticas. A condição otimizada foi pH 8,0, 37°C e 100 rpm, em meio contendo 30 g L-1 de glicose e extrato de levedura atingindo a produção de 0,787 g L-1. O pH, temperatura e extrato de levedura foram as variáveis significativas (p 0,05). Extrato de levedura e pH apresentaram efeito positivo para a produção do polímero. A síntese de ácido lático, fórmico e acético também foi analisada. Este estudo demonstra a viabilidade de utilização de ferramentas estatísticas para otimizar os parâmetros físicos e nutricionais para a produção de ácido hialurônico, permitindo a melhoria do processo fermentativo.(AU)


Subject(s)
Animals , Fermentation , Hyaluronic Acid/biosynthesis , Streptococcus equi/metabolism
4.
Braz. arch. biol. technol ; Braz. arch. biol. technol;55(6): 927-936, Nov.-Dec. 2012. ilus, tab
Article in English | LILACS | ID: lil-660342

ABSTRACT

The objective of the present study was to develop a functional product from the osmo-dehydrated Fuji apple incorporating FOS with acceptable physical, chemical and sensorial characteristics and potential for commercial-scale production. Some treatments were discarded due to texture and water activity that did not reach the desired quality parameters. The products submitted to the osmo-dehydration treatments presented a greater vitamin C loss. All the treatments obtained sensory scores of 6 in a 9 points scale for all the attributes, except the crispness, indicating good acceptance. The sensory scores and incorporated FOS quantities indicated that the osmo-dehydrated apple products have potential for commercial-scale production.

5.
Ciênc. agrotec., (Impr.) ; 34(5): 1301-1305, Sept.-Oct. 2010. tab
Article in Portuguese | LILACS | ID: lil-567347

ABSTRACT

Foi utilizado o delineamento fatorial completo 2³ para estudar o efeito das variáveis de processo no descascamento químico de raízes do yacon, cultivadas na região metropolitana de Curitiba, estado do Paraná. Foram realizados 11 experimentos, com três repetições no ponto central, nos quais foram avaliados em três níveis a concentração da solução de hidróxido de sódio, por cento (g/100 mL) [6, 10, 14], temperatura da solução de hidróxido de sódio, °C [70, 80, 90] e tempo de permanência na solução de hidróxido de sódio, minutos [2,4,6]. Todas as variáveis estudadas afetaram de forma significativa (p<0,05) o rendimento das raízes submetidas ao descascamento químico. A variável mais importante para o rendimento foi o tempo de permanência na solução de hidróxido de sódio. O modelo obtido para a resposta percentual de rendimento foi adequado, com R² aj = 0,8497 e com falta de ajuste não significativa (p = 0,9312), podendo ser utilizado para fins preditivos. No ponto central, foi obtido um rendimento satisfatório (84 por cento a 87 por cento) e elevado percentual de casca removida (96 por cento a 98 por cento), indicando que o tratamento com 10 por cento de solução de hidróxido de sódio a temperatura de 80º C por 4 minutos, pode ser empregado no descascamento químico das raízes do yacon.


A full factorial design 2³ was used to evaluate the effect of process variables in chemical peeling of yacon roots, cultivated in Curitiba, State of Paraná. Eleven treatments, with three central points, were done in which they had been evaluated at three different levels of sodium hydroxide solution, percent (g/100 mL) [6, 10, 14], temperature of the same solution, °C [70, 80, 90], and residence time in the sodium hydroxide solution, minutes [2, 4, 6]. All the studied variables had affected significantly (p<0.05) the yield of yacon roots subjected to chemical peeling. The variable that most affected the yield was the time of permanence in the sodium hydroxide solution. The mathematical model obtained for the yield ( percent) was good with R² aj = 0.8497, and non significant lack of fit (p=0.9312).Therefore, the model can be used for predictive purposes. In the central point a satisfactory yield (84 percent to 87 percent) with a high percentage of removed peel was obtained (96 percent to 98 percent) indicating that the treatment with 10 percent of sodium hydroxide solution, temperature of 80º C per 4 minutes can be used in the chemical peeling of yacon roots.

6.
Acta sci., Biol. sci ; Acta sci., Biol. sci;32(3): 229-233, jul.-set. 2010. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1460664

ABSTRACT

The effect of the variables pantothenic acid, yeast extract and sodium chloride, as well as the cell permeabilization technique, were investigated on the formation of levan, ethanol, sorbitol and biomass of Zymomonas mobilis, using a 24-1 fraction factorial design. Cell growth was determined by turbidimetry at 605 nm, relating it to a biomass with a dry weight calibration curve. Reducing sugars were quantified according to Somogyi and Nelson. Total sugars were quantified by the phenol-sulfuric acid method, sorbitol by HPLC and ethanol. The levan produced was precipitated by the addition of absolute ethanol and quantified in fructose units. In levan biosynthesis, the variable that had the largest contribution was cell condition. The results suggested that the factors that most affected biomass and ethanol formation were sodium chloride concentration and cell condition that affected negatively on production. For sorbitol, the variable that had a significant effect was permeabilization, which decreased its synthesis. Studies to amplify the range of established factors would be important.


A influência das variáveis: ácido pantotênico, extrato de levedura, cloreto de sódio, e a técnica de permeabilização celular foram investigadas na formação de levana, sorbitol, etanol e biomassa de Zymomonas mobilis utilizando um delineamento estatístico fatorial fracionado 24-1. A biomassa foi determinada por turbidimetria, Os açúcares redutores foram quantificados por Somogy e Nelson, açúcar total por Fenol Sulfúrico, sorbitol por HPLC e etanol por micro-destilação. A levana produzida foi precipitada com etanol absoluto e determinada como unidade de frutose. Na biossíntese de levana, a variável que mais contribuiu foi a condição celular. Os resultados sugerem que, para a formação da biomassa e etanol, os fatores que mais interferiram foram a concentração de cloreto de sódio e a condição celular que influencia negativamente a produção. Para o sorbitol, a variável que teve efeito significativo foi a permeabilização celular que atuou diminuindo a sua síntese. Estudos que ampliam a faixa de variação dos fatores estabelecidos são interessantes.


Subject(s)
Biomass , Sodium Chloride/administration & dosage , Fructans/chemical synthesis , Sorbitol/chemical synthesis , Zymomonas/growth & development , Pantothenic Acid/administration & dosage , Ethanol/chemical synthesis , Yeasts/enzymology , Cell Membrane Permeability
7.
Acta sci., Biol. sci ; Acta sci., Biol. sci;32(3): 229-233, jul.-set. 2010.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1460666

ABSTRACT

The effect of the variables pantothenic acid, yeast extract and sodium chloride, as well as the cell permeabilization technique, were investigated on the formation of levan, ethanol, sorbitol and biomass of Zymomonas mobilis, using a 24-1 fraction factorial design. Cell growth was determined by turbidimetry at 605 nm, relating it to a biomass with a dry weight calibration curve. Reducing sugars were quantified according to Somogyi and Nelson. Total sugars were quantified by the phenol-sulfuric acid method, sorbitol by HPLC and ethanol. The levan produced was precipitated by the addition of absolute ethanol and quantified in fructose units. In levan biosynthesis, the variable that had the largest contribution was cell condition. The results suggested that the factors that most affected biomass and ethanol formation were sodium chloride concentration and cell condition that affected negatively on production. For sorbitol, the variable that had a significant effect was permeabilization, which decreased its synthesis. Studies to amplify the range of established factors would be important.


The effect of the variables pantothenic acid, yeast extract and sodium chloride, as well as the cell permeabilization technique, were investigated on the formation of levan, ethanol, sorbitol and biomass of Zymomonas mobilis, using a 24-1 fraction factorial design. Cell growth was determined by turbidimetry at 605 nm, relating it to a biomass with a dry weight calibration curve. Reducing sugars were quantified according to Somogyi and Nelson. Total sugars were quantified by the phenol-sulfuric acid method, sorbitol by HPLC and ethanol. The levan produced was precipitated by the addition of absolute ethanol and quantified in fructose units. In levan biosynthesis, the variable that had the largest contribution was cell condition. The results suggested that the factors that most affected biomass and ethanol formation were sodium chloride concentration and cell condition that affected negatively on production. For sorbitol, the variable that had a significant effect was permeabilization, which decreased its synthesis. Studies to amplify the range of established factors would be important.

8.
Acta Sci. Biol. Sci. ; 32(3): 229-233, 2010. tab, graf
Article in English | VETINDEX | ID: vti-6619

ABSTRACT

The effect of the variables pantothenic acid, yeast extract and sodium chloride, as well as the cell permeabilization technique, were investigated on the formation of levan, ethanol, sorbitol and biomass of Zymomonas mobilis, using a 24-1 fraction factorial design. Cell growth was determined by turbidimetry at 605 nm, relating it to a biomass with a dry weight calibration curve. Reducing sugars were quantified according to Somogyi and Nelson. Total sugars were quantified by the phenol-sulfuric acid method, sorbitol by HPLC and ethanol. The levan produced was precipitated by the addition of absolute ethanol and quantified in fructose units. In levan biosynthesis, the variable that had the largest contribution was cell condition. The results suggested that the factors that most affected biomass and ethanol formation were sodium chloride concentration and cell condition that affected negatively on production. For sorbitol, the variable that had a significant effect was permeabilization, which decreased its synthesis. Studies to amplify the range of established factors would be important.(AU)


A influência das variáveis: ácido pantotênico, extrato de levedura, cloreto de sódio, e a técnica de permeabilização celular foram investigadas na formação de levana, sorbitol, etanol e biomassa de Zymomonas mobilis utilizando um delineamento estatístico fatorial fracionado 24-1. A biomassa foi determinada por turbidimetria, Os açúcares redutores foram quantificados por Somogy e Nelson, açúcar total por Fenol Sulfúrico, sorbitol por HPLC e etanol por micro-destilação. A levana produzida foi precipitada com etanol absoluto e determinada como unidade de frutose. Na biossíntese de levana, a variável que mais contribuiu foi a condição celular. Os resultados sugerem que, para a formação da biomassa e etanol, os fatores que mais interferiram foram a concentração de cloreto de sódio e a condição celular que influencia negativamente a produção. Para o sorbitol, a variável que teve efeito significativo foi a permeabilização celular que atuou diminuindo a sua síntese. Estudos que ampliam a faixa de variação dos fatores estabelecidos são interessantes.(AU)


Subject(s)
Fructans/chemical synthesis , Sorbitol/chemical synthesis , Zymomonas/growth & development , Biomass , Pantothenic Acid/administration & dosage , Sodium Chloride/administration & dosage , Ethanol/chemical synthesis , Cell Membrane Permeability , Yeasts/enzymology
9.
Acta sci., Biol. sci ; 32(3): 229-233, 2010.
Article in English | VETINDEX | ID: vti-765735

ABSTRACT

The effect of the variables pantothenic acid, yeast extract and sodium chloride, as well as the cell permeabilization technique, were investigated on the formation of levan, ethanol, sorbitol and biomass of Zymomonas mobilis, using a 24-1 fraction factorial design. Cell growth was determined by turbidimetry at 605 nm, relating it to a biomass with a dry weight calibration curve. Reducing sugars were quantified according to Somogyi and Nelson. Total sugars were quantified by the phenol-sulfuric acid method, sorbitol by HPLC and ethanol. The levan produced was precipitated by the addition of absolute ethanol and quantified in fructose units. In levan biosynthesis, the variable that had the largest contribution was cell condition. The results suggested that the factors that most affected biomass and ethanol formation were sodium chloride concentration and cell condition that affected negatively on production. For sorbitol, the variable that had a significant effect was permeabilization, which decreased its synthesis. Studies to amplify the range of established factors would be important.


The effect of the variables pantothenic acid, yeast extract and sodium chloride, as well as the cell permeabilization technique, were investigated on the formation of levan, ethanol, sorbitol and biomass of Zymomonas mobilis, using a 24-1 fraction factorial design. Cell growth was determined by turbidimetry at 605 nm, relating it to a biomass with a dry weight calibration curve. Reducing sugars were quantified according to Somogyi and Nelson. Total sugars were quantified by the phenol-sulfuric acid method, sorbitol by HPLC and ethanol. The levan produced was precipitated by the addition of absolute ethanol and quantified in fructose units. In levan biosynthesis, the variable that had the largest contribution was cell condition. The results suggested that the factors that most affected biomass and ethanol formation were sodium chloride concentration and cell condition that affected negatively on production. For sorbitol, the variable that had a significant effect was permeabilization, which decreased its synthesis. Studies to amplify the range of established factors would be important.

10.
Semina ciênc. agrar ; 31(2): 391-404, 2010. tab, ilus, graf
Article in Portuguese | VETINDEX | ID: biblio-1498594

ABSTRACT

Water loss and sugar gain were modeling during the osmotic dehydration process of cylinders of apple. The transfer of solute to the fruit and the water to the solution was based on Ficks 2nd law generalized for simultaneous diffusion and solved by the finite element method using the software COMSOL Multiphysics 3.2. The main and cross diffusion coefficients, the relationship between the mass transfer and mass conductivity coefficients, as well, the Biot number were determined on the simulation with the implementation of the simplex optimization method through minimization of the percentage deviations. The value of deviation between the experimental and the simulated data were 5,76% for sucrose and 2,95 for water. The simulation despising the Biot number indicated that the resistance of the film can be disregarded in the phenomenon of mass transfer studied. The system developed to simulate solute and water diffusion will permit control and modulation of the sugar content in cylinder of apple.


A perda de água e o ganho de açúcar foram modelados durante o processo de desidratação osmótica de cilindros de maçã. A transferência de soluto para a fruta e de água para a solução,  foi modelada com base na 2ª Lei generalizada de Fick para difusão simultânea e resolvida por meio do método de elementos finitos utilizando o software COMSOL Multiphysics 3.2. Os coeficientes de difusão principais e cruzados, a relação entre o coeficiente de transferência de massa e o de condutividade mássica bem como o número de Biot foram determinados na simulação com a aplicação do método de otimização simplex por meio da minimização dos desvios percentuais. O valor dos desvios entre os dados experimentais e simulados foi de 5,76% para a sacarose e 2,95% para a água. A simulação, desprezando o número de Biot, indicou que a resistência externa pode ser desconsiderada no fenômeno de transferência de massa estudado. O sistema desenvolvido para simular a difusão da água e do soluto permitirá o controle e a modulação do conteúdo de açúcar nos cilindros de maçã.


Subject(s)
Osmosis , Malus , Dehydration , Diffusion
11.
Cell Biochem Funct ; 26(3): 320-8, 2008 Apr.
Article in English | MEDLINE | ID: mdl-17990295

ABSTRACT

The effects of chlorogenic acid (CA) on hepatic glucose output, blood glucose levels and on glucose tolerance were analysed. Hepatic uptake of CA and its effects on hepatic catabolism of L-alanine and glucose-6-phosphatase (G-6-Pase) activity were also evaluated. CA (1 mM) inhibited about 40% of G-6-Pase activity (p < 0.05) in the microsomal fraction of hepatocytes, but no effect was observed on production of glucose from gluconeogenesis or on L-alanine catabolism, at various concentrations of CA (0.33, 0.5 and 1 mM), in liver perfusion experiments. Since there were indications of a lack of uptake of CA by the liver, it is possible that this compound did not reach sufficiently high intracellular levels to inhibit the target enzyme. Accordingly, intravenous administration of CA also failed to provoke a reduction in blood glucose levels. However, CA did promote a significant reduction (p < 0.05) in the plasma glucose peak at 10 and 15 min during the oral glucose tolerance test, probably by attenuating intestinal glucose absorption, suggesting a possible role for it as a glycaemic index lowering agent and highlighting it as a compound of interest for reducing the risk of developing type 2 diabetes.


Subject(s)
Blood Glucose/drug effects , Chlorogenic Acid/pharmacology , Liver/metabolism , Animals , Area Under Curve , Chlorogenic Acid/administration & dosage , Glucose/biosynthesis , Glucose Tolerance Test , Glucose-6-Phosphatase/metabolism , Glycerol/metabolism , Hydrogen-Ion Concentration/drug effects , Lactic Acid/metabolism , Liver/drug effects , Liver/enzymology , Male , Pyruvic Acid/metabolism , Rats , Rats, Wistar , Urea/metabolism
12.
Semina cienc. biol. saude ; 26(3): 353-362, jul.-set. 2005. tab
Article in Portuguese | LILACS | ID: lil-429335

ABSTRACT

Este trabalho teve como objetivo desenvolver um aplicativo com métodos de gradiente eficazes na otimização de sistemas alimentares com respostas múltiplas utilizando as funções de Derringer & Suich, incluindo um polinômio de 4º grau para a remoção das descontinuidades dessas funções. O aplicativo foi testado em três sistemas alimentares selecionados na literatura especializada: 1) inativação da lipoxigenase e lípase preservando-se a atividade da fitase durante o processamento hidrotérmico da cevada; 2) otimização simultânea das respostas na formulação de misturas de proteínas; 3) otimização simultânea dos parâmetros de torração de gérmen de milho visando aplicação como ingrediente em alimentos. O programa desenvolvido mostrou ser eficiente e confiável para a otimização em sistemas alimentares multirresposta


Subject(s)
Process Optimization
13.
Braz. arch. biol. technol ; Braz. arch. biol. technol;47(3): 391-397, July 2004. tab, graf
Article in English | LILACS | ID: lil-363418

ABSTRACT

Desenvolvimento microbiano, ação enzimática e reações químicas influenciam a qualidade de suco de laranja natural não-pasteurizado, podendo comprometer características sensoriais e provocar perdas nutricionais. A estabilidade do suco, obtido em extrator de pequeno porte e acondicionado em embalagem de polietileno, foi avaliada em condições isotérmicas e não-isotérmicas de armazenamento em temperaturas entre 4 e 12oC por 72h. Valores de pH, acidez titulável e sólidos solúveis totais não se alteraram significativamente ao longo do armazenamento em todas as condições. Resultados da análise microbiológica mostraram alta contagem inicial de bolores e leveduras, que aumentaram no suco armazenado por 72h na condição não isotérmica onde houve abuso de temperatura (12oC por 4h). Os testes sensoriais mostraram uma pequena redução na aceitação do produto nessa mesma condição. Constatou-se que o suco, no período preconizado como prazo de validade (48h), apresentou perdas inferiores a 20% do teor inicial de ácido ascórbico, independentemente do tratamento. A partir deste momento, a degradação se acentuou, chegando, com 72h de armazenamento, a retenções de 72 a 85%.

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