Food Science and Technology
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/12092
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Resultados da Pesquisa
Item Development of a method for simultaneous analysis of caffeine and taurine in energy drinks by micellar electrokinetic chromatography with diode-array detector(Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2019-09-19) Alves, Alane Cangani; Meinhart, Adriana Dillenburg; Teixeira Filho, José; Godoy, Helena TeixeiraThe objective of this study was to develop, optimize and validate a fast and reliable method for the simultaneous determination of caffeine and taurine contents by micellar electrokinetic chromatography with diode array detector, using direct and indirect detection concomitantly. Multivariate statistical techniques were used as a central composite design and the simultaneous optimization method of responses of Derringer and Suich were used for optimization. The method was applied in the analysis of 73 samples of energy drinks commercialized in Brazil. The optimized method employed a capillary tube with an extended bulb of 50 µm i.d. x 72 cm total length, an electrolyte containing 16.20 mmol.L-1 of benzoic acid and 39.90 mmol.L-1 of SDS, a pH value of 7.26, + 30 kV voltage, direct detection of caffeine at 274 nm and indirect detection of taurine at 230 nm. Validation parameters have demonstrated the reliability and applicability of this method. It was found that more than 50% of the samples were out of the legal limits determined by the Brazilian government regarding the taurine content and 68 % contained caffeine below the value declared on the label. Therefore, the need for greater control concerning the composition of these drinks exists.Item Use of colour parameters for roasted coffee assessment(Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2012-07) Bicho, Natalina Cavaco; Leitão, António Eduardo; Ramalho, José Cochicho; Lidon, Fernando CebolaFast and non-destructive indicators were evaluated as tools to measure the technological quality of Arabica and Robusta coffee. Accordingly, considering the roasting intensity in highly valuable commercial samples, volume, mass, apparent density, moisture, total ash, ash insoluble in hydrochloric acid, and ether extract were characterized. The chromatic parameters L*, C*, H° were measured using illuminants D 65 and C. It was found that in roasted coffee beans, the parameters L∗, C*, H°, and coordinate b* had an antagonist interaction due to an increase in the roasting intensity, whereas after milling, only L* and H° decreased progressively. Considering that the parameters L* and H° followed similar patterns using both illuminants, D 65 and C, it can be concluded that they are appropriate to evaluate coffee colour changes during roasting, enabling a relationship with coffee quality.Item Sensory evaluation of “dulce de leche” with coffee and whey using different affective data analysis methods(Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2011-10) Ferreira, Larissa Oliveira; Pimenta, Carlos José; Pinheiro, Ana Carla Marques; Pereira, Patrícia Aparecida Pimenta; Santos, GabriellaThis study sought to evaluate the acceptance of “dulce de leche” with coffee and whey. The results were analyzed through response surface, ANOVA, test of averages, histograms, and preference map correlating the global impression data with results of physical, physiochemical and sensory analysis. The response surface methodology, by itself, was not enough to find the best formulation. For ANOVA, test of averages, and preference map it was observed that the consumers’ favorite “dulce de leche” were those of formulation 1 (10% whey and 1% coffee) and 2 (30% whey and 1% coffee), followed by formulation 9 (20% whey and 1.25% coffee). The acceptance of samples 1 and 2 was influenced by the higher acceptability in relation to the flavor and for presenting higher pH, L*, and b* values. It was observed that samples 1 and 2 presented higher purchase approval score and higher percentages of responses for the ‘ideal’ category in terms of sweetness and coffee flavor. It was found that consumers preferred the samples with low concentrations of coffee independent of the concentration of whey thus enabling the use of whey and coffee in the manufacture of dulce de leche, obtaining a new product.Item Detection of enterotoxins produced by B. cereus through PCR analysis of ground and roasted coffee samples in Rio de Janeiro, Brazil(Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2011-04) Souza, Cyllene de Matos Ornelas da Cunha Corrêa de; Abrantes, Shirley de Mello PereiraCoffee is one of the most appreciated drinks in the world. Coffee ground is obtained from the fruit of a small plant that belongs to the genus Coffea. Coffea arabica and Coffea canephora robusta are the two most commercially important species. They are more commonly known as arabica and robusta, respectively. Two-thirds of Coffea arabica plants are grown in South and Central America, and Eastern Africa - the place of origin for this coffee species. Contamination by microorganisms has been a major matter affecting coffee quality in Brazil, mainly due to the harvesting method adopted. Brazilian harvests are based on fruits collected from the ground mixed with those that fall on collection cloths. As the Bacillus cereus bacterium frequently uses the soil as its environmental reservoir, it is easily capable of becoming a contaminant. This study aimed to evaluate the contamination and potential of B. cereus enterotoxin genes encoding the HBL and NHE complexes, which were observed in strains of ground and roasted coffee samples sold in Rio de Janeiro. The PCR (Polymerase Chain Reaction) results revealed high potential of enterotoxin production in the samples. The method described by Speck (1984) was used for the isolation of contaminants. The investigation of the potential production of enterotoxins through isolates of the microorganism was performed using the B. cereus enterotoxin Reverse Passive Latex Agglutination test-kit (BCET-RPLA, Oxoid), according to the manufacturer’s instructions. The potential of enterotoxin production was investigated using polymerase chain reaction (PCR) methods for hblA, hblD and hblC genes (encoding hemolysin HBL) and for nheA, nheB and nheC genes (encoding non-hemolytic enterotoxin - NHE). Of all the 17 strains, 100% were positive for at least 1 enterotoxin gene; 52.9% (9/17) were positive for the 3 genes encoding the HBL complex; 35.3% (6/17) were positive for the three NHE encoding genes; and 29.4% (5/17) were positive for all enterotoxic genes.Item Total phenolic content and primary antioxidant capacity of aqueous extracts of coffee husk: chemical evaluation and beverage development(Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2019-06) Neves, Jorge Vitório Gomes das; Borges, Marília Viana; Silva, Daniel de Melo; Leite, Cristina Xavier dos Santos; Santos, Mariana Romana Correia; Lima, Neuma Gonçalves Barbosa de; Lannes, Suzana Caetano da Silva; Silva, Marcondes Viana daThis study aimed to evaluate the efficiency of aqueous extraction to obtain bioactive phytochemicals from grains and residual husk of organic Arabic coffee, as well as to develop a beverage with high antioxidant capacity and assess its sensorial acceptability. Aqueous extracts were obtained from dried and crushed coffee beans and husk. Various extraction methods were used to select the one capable of extracting the most amount of total phenolic constituents. The decoction without mechanical agitation was highlighted as the best method, from which the chemical characterization, antioxidant capacity and the presence of antinutrients were investigated. Three beverage formulations were prepared with coffee husk extract and added in different proportions to concentrated pineapple juice. The beverages were analyzed for antioxidant capacity, microbiological properties and sensorial acceptance. No hemagglutinins and low oxalate content were found in the samples. The antioxidant capacity of the aqueous husk extract was higher than that of the grains. The beverage made with the addition of concentrated pineapple juice was sensorially preferred by the tasters. In addition, it contributed to raise the antioxidant capacity of the beverage. It was concluded that the aqueous extract of coffee husk appears as a new alternative for the beverage industry.Item Oxidative stability of soybean oil added to coffee husk extract (Coffea arabica L.) under accelerated storage conditions(Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2017-12) Ribeiro, Elisa Franco; Jorge, NeuzaSeveral plants have been studied as potential sources of natural antioxidants for use in the food industry, especially polyphenols. The aim of this study was to evaluate the effects of hydroalcoholic extract from coffee husk on the oxidative stability of soybean oil when stored in an oven. Samples were maintained at a temperature of 60 °C and their oxidative stability was evaluated once every 5 days for a period of 20 days through the Rancimat equipament and analysis of peroxide value, conjugated dienes and tocopherols retention. The oxidation rate in terms of mass gain was evaluated once every 24 hours for a period of 24 days. Although the antioxidant TBHQ showed a better efficiency in the inhibition of oxidation, coffee husk extract showed a synergistic effect when used with the synthetic, delaying the appearance of degradation products. In addition, the freeze-dried extract showed the ability to reduce the mass-gain rate when used alone as well as when used in combination with the synthetic antioxidant butyl hydroxyanisole (BHA), noting a synergistic effect on oxidative stability between the extract and the BHA. Therefore, coffee husk extract could be considered a source of natural antioxidants for synthetic antioxidants substitution.Item Volatile compounds profiles in unroasted Coffea arabica and Coffea canephora beans from different countries(Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2017-07) Knysak, DanielAroma is the most important factor in assessing the quality of coffee. The volatile compounds profile could be very important to confirm the authenticity of Coffea arabica. The study was carried out on two species of unroasted coffee beans: Coffea arabica from Colombia and Nepal and Coffea robusta from Uganda and Vietnam. Both Coffea arabica and Coffea canephora were imported to the country of analysis approximately 5 months prior to the research. Before the analysis, the coffee beans were kept in a sealed, dark container, at 21 °C. The tests were performed using an electronic nose. Its functioning is based on gas chromatography with two columns of different polarities in parallel and with 2 ultra sensitive Flame Ionization Detectors (FID). With multivariate statistics – Principal Components Analysis – it was possible to reduce the number of links and present them in two dimensions, which allowed for the unambiguous identification and assignment of samples to a particular species of coffee. By using an electronic nose, one can distinguish and group unroasted coffee beans’ flavours depending on the country of origin and species.Item Personal characteristics of coffee consumers and non-consumers, reasons and preferences for foods eaten with coffee among adults from the Federal District, Brazil(Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2016-07) Sousa, Alessandra Gaspar; Machado, Liliane Maria Messias; Silva, Eduardo Freitas da; Costa, Teresa Helena Macedo daThe aim of this study is to describe the characteristics of consumers and non-consumers, the reasons and foods associated with coffee intake among adults from the Federal District, Brazil. This is a cross-sectional population-based survey conducted by telephone interview (n= 1,368). We collected information on detailed coffee intake, socio-demographic aspects and personal characteristics. The coffee had an average daily intake of 319 mL. Individuals were more likely to drink coffee at an older age (68%) and with higher body mass index (58%). The most cited reason for consuming coffee was the “personal pleasure” (48%), followed by “habit / tradition” of consuming coffee. Among non-consumers of this beverage, the main reason was not liking the taste and / or aroma of coffee (62%). The method of coffee preparation used was by infusion (86%) and sugar was the main sweetener used by 83% of consumers. The majority of consumers (59%) reported consuming coffee with certain foods such as bakery products. The results from our study may suggest that the popularity of coffee can be attributed to its taste, personal pleasure and habit, and the consumption is more likely to occur with the advance of age and with intake of other foods.Item Comparison of capillary electrophoresis and high performance liquid chromatography methods for caffeine determination in decaffeinated coffee(Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2013-01) Bizzotto, Carolina Schaper; Meinhart, Adriana Dillenburg; Ballus, Cristiano Augusto; Ghiselli, Gislaine; Godoy, Helena TeixeiraDecaffeinated coffee accounts for 10 percent of coffee sales in the world; it is preferred by consumers that do not wish or are sensitive to caffeine effects. This article presents an analytical comparison of capillary electrophoresis (CE) and high performance liquid chromatography (HPLC) methods for residual caffeine quantification in decaffeinated coffee in terms of validation parameters, costs, analysis time, composition and treatment of the residues generated, and caffeine quantification in 20 commercial samples. Both methods showed suitable validation parameters. Caffeine content did not differ statistically in the two different methods of analysis. The main advantage of the high performance liquid chromatography (HPLC) method was the 42-fold lower detection limit. Nevertheless, the capillary electrophoresis (CE) detection limit was 115-fold lower than the allowable limit by the Brazilian law. The capillary electrophoresis (CE) analyses were 30% faster, the reagent costs were 76.5-fold, and the volume of the residues generated was 33-fold lower. Therefore, the capillary electrophoresis (CE) method proved to be a valuable analytical tool for this type of analysis.Item Technological properties of precooked flour containing coffee powder and rice by thermoplastic extrusion(Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2013-01) Silva, Reginaldo Ferreira da; Pereira, Rosemary Gualberto Fonseca Alvarenga; Ascheri, José Luis Ramirez; Ascheri, Diego Palmiro RamirezAlthough Brazil is a country of tradition in both the production and consumption of coffee, the most of the coffee is consumed as a beverage, which reduces greatly the competitiveness on international market, for reducing the chances of supplying the product under other forms of consumption. Owing to that, the aim of this study was developing a precooked mixed flour containing coffee powder and rice for use in coffee flavored products. Mixtures of rice and coffee in the proportions of 900:100, 850:150 and 800:200 g, respectively, were processed in a single screw extruder (Brabender DS-20, Duisburg, German) and the effect of the extrusion process on the variables moisture content (16%, 18% and 20%) and temperature in the third extruding zone (140 °C, 160 °C and 180 °C) was studied. The results for expansion index ranged from 2.91 to 11.11 mm in diameter; the water absorption index from 4.59 to 6.33 g gel/g sample and the water solubility index varied from 4.05% to 8.57%. These results showed that, despite coffee powder influenced the variables studied, the expanded product after milling resulted in a extruded mixture with good absorption and water solubility indices, which favors the use of the precooked mixed flour for human consumption.