Rio de Janeiro, Brazil
Rio de Janeiro, Brazil

Time filter

Source Type

Deliza R.,Embrapa Food Technology | Rosenthal A.,Embrapa Food Technology | Hedderley D.,Crop and Food Research | Jaeger S.R.,The Horticulture and Food Research Institute of New Zealand Ltd
Journal of Sensory Studies | Year: 2010

Papaya is a popular fruit among Brazilian consumers, but one problem is that fruit ripens quickly due to the high temperatures of the country. Irradiation is an effective way of slowing down ripening, hereby increasing shelf-life, but consumer acceptance of this novel technology is paramount for its successful introduction by industry. Using conjoint analysis, this research measures consumer acceptance of irradiated papaya fruit in a sample of urban Brazilian consumers. The study assesses the joint influence of product appearance, price and information about the use of irradiation for consumer choice. Real fruit was used and consumer responses were collected through intercept interviews in supermarkets. These two empirical aspects add external validity to the research. The responses from a convenience sample of 168 consumers from Rio de Janeiro revealed that the product appearance, as a proxy for product quality, was the most important factor influencing decision to purchase papaya. Price was of lesser importance. The participants in this study did not reject papaya due to the labelled information about the use of irradiation. This suggests irradiation as a viable alternative for fruit producers. Consumers demonstrated no knowledge about food irradiation, and education initiatives may be useful as a strategy to aid commercial introduction of irradiated papaya in Brazil. © 2009, Wiley Periodicals, Inc.


Silva-Angulo A.B.,Biopolis S.L. | Zanini S.F.,Federal University of Espirito Santo | Rodrigo D.,CSIC - Institute of Agricultural Chemistry and Food Technology | Rosenthal A.,Embrapa Food Technology | Martinez A.,CSIC - Institute of Agricultural Chemistry and Food Technology
Food Control | Year: 2014

The aim of this work was to compare the growth kinetics of Listeria innocua and Listeria monocytogenes serovar 4b exposed to carvacrol, considering two initial inoculum sizes, and the occurrence of sublethal damage in these cell populations, by plating them in selective and non-selective medium. Bacteria were grown in TSB supplemented with carvacrol: 0.0μL/mL (control), 0.100μL/mL and 0.175μL/mL. The increase in carvacrol concentration resulted in an extended lag phase and lower maximum growth rate in comparison with the untreated cells (p≤0.05). In the presence of carvacrol, the lower inoculum size showed an increased growth rate and relatively longer lag phase compared to the higher inoculum size (p≤0.05). The cells of L.innocua and L.monocytogenes had a greater extension of lag time, slower growth rate and higher percentage of injured cells when treated with carvacrol (p≤0.05). Results also indicated that L.monocytogenes grows faster than L.innocua when treated with carvacrol, this scenery could compromise the use of L.innocua as a surrogate for L.monocytogenes serovar 4b for this antimicrobial substance. Finally, it was shown that good growth control of Listeria was achieved with 0.175μL/mL of carvacrol. © 2013 Elsevier Ltd.


Carvalho C.W.P.,Embrapa Food Technology | Takeiti C.Y.,Embrapa Food Technology | Onwulata C.I.,U.S. Department of Agriculture | Pordesimo L.O.,ADM Alliance Nutrition Inc.
Journal of Food Engineering | Year: 2010

Corn meal of various particle sizes ranging from 180 to 710 μm were processed in a twin-screw extruder to produce directly expanded extrudates. The extrusion process effects on the specific mechanical energy (SME), expansion indexes (radial, longitudinal and volumetric), pasting viscosity, water absorption index (WAI) texture properties, and microstructure were determined. Increasing the particle size decreased the SME input. Extrudates produced with corn meal of higher particle sizes expanded more than extrudates produced with smaller particle sizes. For all treatments there was no peak viscosity at 95 °C. But expanded corn meal extrudate from the 180 μm fraction showed a discontinuous gel matrix phase. Increasing corn meal particle size decreased WAI values. The mechanical resistance of the extrudates from the smallest particle size was significantly higher (p < 0.05) than that of the largest particle size. The microstructure of raw corn meal revealed large fractured particles with small rounded particles adhering to the surface. © 2009 Elsevier Ltd.


Candea T.V.,New University of Lisbon | Monteiro F.S.,Federal University of Rio de Janeiro | Tonon R.V.,Embrapa Food Technology | Cabral L.M.C.,Embrapa Food Technology
Food Engineering Reviews | Year: 2015

The aim of this work was to study the effect of process variables on the production of flaxseed oil emulsions by cross-flow membrane emulsification. The process was carried out using an ultrafiltration α-alumina membrane with mean pore size of 0.2 µm, and Tween 20 was used as surfactant. The effect of transmembrane pressure (1.5–4.5 bar), cross-flow velocity (3–8 m/s) and surfactant concentration (1–3 %) on the dispersed phase flux, emulsion stability and droplet size distribution and uniformity was evaluated according to a 23 central composite experimental design. Results showed that all the emulsions presented unimodal droplets distribution, and the average droplet diameter was 1.50 μm. Among all the variables studied, only transmembrane pressure had significant influence on the dispersed phase flux—the increase in transmembrane pressure resulted in higher dispersed phase flux. The other variables did not affect any of the analyzed responses within the studied ranges. © 2014, Springer Science+Business Media New York.


Gurak P.D.,Federal University of Rio de Janeiro | Cabral L.M.C.,Embrapa Food Technology | Rocha-Leao M.H.M.,Federal University of Rio de Janeiro | Matta V.M.,Embrapa Food Technology | Freitas S.P.,Federal University of Rio de Janeiro
Journal of Food Engineering | Year: 2010

The objective of this work was to evaluate the concentration of grape juice by reverse osmosis (RO). Preliminarily, a factorial design was carried out in which the independent variables were transmembrane pressure (40, 50 and 60 bar) and temperature (20, 30 and 40 °C) of the process, and the dependent variables were pH, content of soluble solids, acidity, concentration of phenolic compounds and those of monomeric and total anthocyanins, colour index, colour density, and permeate flux. None of the experiments resulted in significant changes in the juice characteristics. The best process conditions, 60 bar transmembrane pressure and 40 °C, was selected based on the resulting high permeate flux value. Subsequently, a new trial was performed in order to determine whether increasing the temperature from 40 to 50 °C would result in any changes in the juice characteristics. The transmembrane pressure was kept at 60 bar, which was also the maximum value that could be applied by the equipment. Under these conditions, an increase in permeate flux was achieved with no significant difference in the physical or chemical parameters of the product compared to the best condition corresponding to the factorial design. The physical and chemical properties of the concentrated juice increased in proportion to the volumetric concentration factor, indicating the technical feasibility of reverse osmosis for pre-concentrating grape juice. © 2009 Elsevier Ltd. All rights reserved.


Nascimento E.M.D.G.C.D.,Federal Rural University of Rio de Janeiro | Carvalho C.W.P.,Embrapa Food Technology | Takeiti C.Y.,Embrapa Food Technology | Freitas D.D.G.C.,Embrapa Food Technology | Ascheri J.L.R.,Embrapa Food Technology
Food Research International | Year: 2012

In the production of oil from sesame (Sesamum indicum L.) seeds, a coproduct is obtained which is rich in protein and fiber contents. Mixtures of semi-defatted sesame cake (SDSC) (0-20%) and corn grits were processed in a single screw extruder at screw speed ranging from 324 to 387. rpm to improve the nutritional value of corn expanded extrudates. Chemical composition of raw and extruded materials, sectional expansion index (SEI), texture properties, color, paste viscosity, microstructure and sensory analysis of the extrudates were performed. The addition of SDSC increased protein, fat and ash content of corn extrudates, whereas carbohydrate content was reduced. The addition of SDSC reduced the sectional expansion of the corn extrudates and increased puncture force. SDSC-corn extrudates were darker than non-SDSC-corn extrudates. Increasing SDSC increased the number of cells similar to those of commercial corn extrudates with small cells. Sensory analysis showed 20% SDSC-corn extrudates to be acceptable and nutritional balanced. The use of SDSC on corn extrudates up to 20% is an alternative to improve nutritional value keeping good sensory characteristics. © 2011 Elsevier Ltd.


Ares G.,University of the Republic of Uruguay | De Saldamando L.,University of the Republic of Uruguay | Gimenez A.,University of the Republic of Uruguay | Deliza R.,Embrapa Food Technology
Appetite | Year: 2014

Interest in understanding how foods affect consumers' perceived wellbeing has grown in the last decade due to the increasing need to modify dietary patterns. Considering that wellbeing is a broad concept that lacks of a unique definition, in order to use and measure this concept it is necessary to explore how consumers understand it, particularly in the context of food consumption. The aim of the present work was to investigate consumers' perception of wellbeing in a food-related context using an exploratory qualitative approach. A study was carried out with 120 Uruguayan participants using three qualitative techniques: word association, open-ended questions and free listing. Wellbeing in a food-related context was strongly associated with physical health. The expected effects of foods on wellbeing were mainly related to non-communicable diseases such as high cholesterol levels, hypertension, and cardiovascular diseases. However, hedonic and emotional aspects of food consumption were also salient for consumers perceived wellbeing. The information gathered in this study can contribute to the development of scales for measuring consumer perceived wellbeing when consuming foods. © 2013 Elsevier Ltd.


Garcia L.C.,University of Campinas | Tonon R.V.,Embrapa Food Technology | Hubinger M.D.,University of Campinas
Drying Technology | Year: 2012

The objective of this work was to evaluate the influence of oil concentration and homogenization pressure on the emulsion and particle properties during the microencapsulation of basil essential oil by spray drying, using gum arabic as the wall material. Experiments were planned according a 2 2 rotational central composite design. The independent variables were oil concentration with respect to total solids (10-25%) and homogenization pressure (0-100 MPa). Emulsions were analyzed for droplet mean diameter, stability, and viscosity, and particles were analyzed for oil retention, moisture content, particle size, and morphology. Emulsion viscosity was not affected by any of the independent variables. The increase in the homogenization pressure from 0 to 100 MPa resulted in smaller emulsion droplet size (down to 0.40 μm) and, consequently, higher oil retention (up to 95%). On the other hand, higher oil loads (25%) resulted in poorer oil retention (51.22%). Microencapsulation of basil essential oil using gum arabic as the wall material proved to be a suitable process to obtain powdered basil essential oil, presenting great oil retention with the use of lower oil concentration and higher homogenization pressure. © 2012 Copyright Taylor and Francis Group, LLC.


Carneiro H.C.F.,University of Campinas | Tonon R.V.,Embrapa Food Technology | Grosso C.R.F.,University of Campinas | Hubinger M.D.,University of Campinas
Journal of Food Engineering | Year: 2013

This study aimed at evaluating the potential of maltodextrin combination with different wall materials in the microencapsulation of flaxseed oil by spray drying, in order to maximize encapsulation efficiency and minimize lipid oxidation. Maltodextrin (MD) was mixed with gum Arabic (GA), whey protein concentrate (WPC) or two types of modified starch (Hi-Cap 100™ and Capsul TA®) at a 25:75 ratio. The feed emulsions used for particle production were characterized for stability, viscosity and droplet size. The best encapsulation efficiency was obtained for MD:Hi-Cap followed by the MD:Capsul combination, while the lowest encapsulation efficiency was obtained for MD:WPC, which also showed poorer emulsion stability. Particles were hollow, with the active material embedded in the wall material matrix, and had no apparent cracks or fissures. During the oxidative stability study, MD:WPC combination was the wall material that best protected the active material against lipid oxidation. © 2012 Elsevier Ltd. All rights reserved.


Bisconsin-Junior A.,São Paulo State University | Rosenthal A.,Embrapa Food Technology | Monteiro M.,São Paulo State University
Food and Bioprocess Technology | Year: 2014

The influence of high hydrostatic pressure (HHP) on Pêra Rio orange juice was investigated using response surface methodology. A central composite design was used to evaluate the effects of three processing conditions (independent variables), namely pressure (100-600 MPa), temperature (30-60 °C) and time (30-360 s), on the native microflora and pectin methylesterase (PME) activity of orange juice. Analysis of variance showed that second-order polynomial models fitted well with the experimental data for PME residual activity (R 2 = 0.9586, p < 0.001) and aerobic microorganism count (R 2 = 0.9879, p < 0.001). The optimum HHP processing conditions to produce orange juice with PME residual activity of less than 20 % and low microorganism count (<2 log cycles CFU/mL) were 550 to 600 MPa, 55 to 60 °C and 330 to 360 s. © 2013 Springer Science+Business Media New York.

Loading Embrapa Food Technology collaborators
Loading Embrapa Food Technology collaborators