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1.
Artigo em Inglês | MEDLINE | ID: mdl-36293801

RESUMO

This study aimed to investigate the effect of spray drying (SD) and freeze-drying (FD) on the microencapsulation of green coffee extracts by using polydextrose (PD) and inulin (IN) as encapsulating agents and their physicochemical, bioactive compounds' stability, phenolic compounds' bioaccessibility after digestion, and sensory effects in unfermented dairy beverages. The extract encapsulated with IN by FD had lower moisture content, water activity, and hygroscopicity, while particles encapsulated by SD exhibited a spherical shape and the structure of the FD products was irregular. No difference was observed in phenolic compounds' bioaccessibility. Dairy beverages with added encapsulated extracts had higher total phenolic content and antioxidant activity. Microencapsulation allowed a controlled release of the bioactive compounds with an increase in the content of caffeine, chlorogenic acid, and trigonelline during storage. The dairy beverage with added extract encapsulated with IN by FD had the highest scores of acceptability regarding the overall impression and purchase intent.


Assuntos
Coffea , Extratos Vegetais , Antioxidantes/química , Bebidas , Cafeína/análise , Ácido Clorogênico/análise , Preparações de Ação Retardada , Inulina/química , Fenóis/química , Extratos Vegetais/química , Laticínios
2.
J Food Sci ; 87(9): 4056-4067, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35986622

RESUMO

Spent coffee grounds (SCG) are a coproduct that causes environmental impacts worldwide. Thus, consciously reusing the SCG is an eminent need. This work aimed to encapsulate phenolic compounds and antioxidants obtained from SCG extracts through spray- and freeze-drying techniques using different isolated and combined wall materials. The dried powders produced were evaluated for moisture content, water activity, bulk density, hygroscopicity, color, content of phenolic compounds and antioxidants, and the results were compared. The results showed that all evaluated treatments resulted in a powdered product with low values of bulk density, moisture and water activity, especially for freeze-drying. The freeze-dried product also showed higher hygroscopicity. Regarding the content of phenolic compounds and antioxidants, both drying methods showed high levels of these compounds in the dried product and good encapsulation efficiency, reaching 83.43%. In most cases, spray-drying and freeze-drying did not differ statistically (p > 0.05) in relation to bioactive compound content and encapsulation efficiency. In relation to wall materials, albumin showed the worst performance in the retention of bioactive compounds. On the other hand, pure gum arabic combined with maltodextrin led to better preservation of these compounds. PRACTICAL APPLICATION: Spent coffee grounds are a coproduct generated in large quantities in the world. The encapsulation of phenolic and antioxidant compounds protects and enables their application in different food matrices. Therefore, the evaluation of different encapsulation methods and wall materials is important to define good process conditions.


Assuntos
Antioxidantes , Café , Albuminas , Antioxidantes/análise , Goma Arábica , Fenóis/análise , Pós , Água
3.
Food Res Int ; 151: 110844, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34980382

RESUMO

The Hedonic Threshold Methodology (HTM), through the determination of compromised acceptance threshold (CAT) and hedonic rejection threshold (HRT), has several applications by the food industry. In order to further increase the field of application of HTM, the objective was to use a mixture design in the Hedonic Threshold Methodology, to enable the determination of hedonic thresholds (CAT and HRT) by varying the intensity of three stimuli simultaneously. It was investigated how much it is possible to replace the NaCl content (1.8% flour weight basis) with two other ingredients (KCL/yeast extract or KCL/enzyme preparation), without compromising the acceptance (CAT) and without resulting in sensory rejection (HRT) of crackers. Reduction in the acceptance started to occur by reducing the NaCl content by around 64% (from 1.81% to 0.651%), with the addition of 1.149% KCl. Two combinations of KCl and yeast extract (1.783% and 0.017%, or 0.693% and 1.107%, respectively) allowed producing a cracker with no NaCl without sensory rejection. The reduction in acceptance also started to occur by reducing the NaCl content by around 40% (from 1.81% to 1.086%), with adding of 0.358% KCl and 0.356% enzyme preparation. A sensory rejection begins to occur by reducing the NaCl content by around 99% (1.81-0.012%), with the addition of 1.215% KCl and 0.573% enzyme preparation (transglutaminase). The use of the mixture design in HTM allowed the unprecedented determination of hedonic thresholds varying three stimuli. This expands the possibilities for applications of sensory thresholds.


Assuntos
Cloreto de Sódio , Paladar , Alimentos , Limiar Sensorial
4.
Food Res Int ; 150(Pt A): 110798, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34865813

RESUMO

Excessive sodium consumption is a worldwide public health concern. The substitution of sodium chloride (NaCl) for potassium chloride (KCl) has been adopted to reduce the sodium concentration in processed foods. The challenge is to make this substitution without affecting the sensory acceptance of foods. In this context, the objective was to determine from which concentrations the replacement of NaCl by KCl results in reduced acceptance (compromised acceptance threshold - CAT) and begins the sensory rejection (hedonic rejection threshold - HRT) of cracker-type biscuits. Using the hedonic thresholds methodology (HTM) by varying a stimulus, CAT and HRT were determined for the concentration of NaCl in crackers and, by varying two stimuli, CAT and HRT, for replacing NaCl with KCl in crackers were determined. Without the addition of KCl, the reduction in acceptance started to occur by reducing the NaCl content by around 60% (from 1.81% to 0.73%); and sensory rejection began to appear by reducing the NaCl content by approximately 93% (1.81% to 0.13%). Reduction in the acceptance started to occur by lowering the NaCl content by around 78% (from 1.81% to 0.397%), with the addition of 0.896% KCl. In addition, by adding KCl, it was possible to reduce 100% NaCl without sensory rejection of the crackers. With these results, cracker industries can reduce the sodium content of their products, contributing to the reduction of population salt intake.


Assuntos
Cloreto de Sódio , Paladar , Fast Foods , Cloreto de Potássio , Sódio
5.
J Sci Food Agric ; 100(6): 2488-2493, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31960433

RESUMO

BACKGROUND: Coffee is a raw material of global interest. Due to its relevance, this work evaluated the performance of calibration models constructed from spectral data obtained using near-infrared spectroscopy (FT-NIR) to determine the pH values and acidity in coffee beans in a practical and non-destructive way. Partial least squares regression was used during the calibration and the cross-validation to optimize the number of latent variables. The predictive capacity of the spectral pre-processing methods was also accessed. RESULTS: The results obtained showed that the best methods of pre-processing were the first derivative for the pH variable and the standard normal variate for the acidity, which produced models with correlations of 0.78 and 0.92, ratios of prediction to deviation of 2.061 and 2.966 and biases of -0.00011 and -0.152 to test set validation, respectively. The average errors between predicted and experimental values were lower than 7%. CONCLUSIONS: FT-NIR was successfully applied to predict properties related to the quality of coffee. The method was demonstrated to be a fast and non-destructive tool which allows the rapid inline evaluation of samples facilitating industrial and commercial processing. © 2020 Society of Chemical Industry.


Assuntos
Coffea/química , Concentração de Íons de Hidrogênio , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Calibragem , Análise dos Mínimos Quadrados , Sementes/química
6.
J Food Sci Technol ; 56(9): 4147-4157, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31477986

RESUMO

Color is a sensory attribute that influences the acceptance of food and dyes are added into food products to provide them attractiveness. In this context, anthocyanins have merged as an alternative to synthetic dyes. This study aimed to develop food model systems of fermented or unfermented dairy beverages containing added microencapsulated anthocyanin-rich extracts from juçara palm fruit. The stabilities of both pigment and beverage throughout storage in opaque or transparent packaging have been evaluated. Acidity, pH and anthocyanin content in both beverages did not vary during 28 days of storage, and the content of bioactive compounds did not decrease over time. A slight overall color difference that is probably invisible to naked eyes was detected between the beverages analyzed at days 0 and 28. The potential of applying microencapsulated natural pigments into dairy matrices is an effort to increase their nutritional and sensorial values.

7.
J Agric Food Chem ; 66(1): 323-330, 2018 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-29286652

RESUMO

Semisynthetic phenol derivatives were obtained from the natural phenols: thymol, carvacrol, eugenol, and guaiacol through catalytic oxychlorination, Williamson synthesis, and aromatic Claisen rearrangement. The compounds characterization was carried out by 1H NMR, 13C NMR, and mass spectrometry. The natural phenols and their semisynthetic derivatives were tested for their antimicrobial activity against the bacteria: Staphylococcus aureus, Escherichia coli, Listeria innocua, Pseudomonas aeruginosa, Salmonella enterica Typhimurium, Salmonella enterica ssp. enterica, and Bacillus cereus. Minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values were determined using concentrations from 220 to 3.44 µg mL-1. Most of the tested compounds presented MIC values ≤220 µg mL-1 for all the bacteria used in the assays. The molecular properties of the compounds were computed with the PM6 method. Through principle components analysis, the natural phenols and their semisynthetic derivatives with higher antimicrobial potential were grouped.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Fenol/farmacologia , Antibacterianos/química , Cimenos , Escherichia coli/efeitos dos fármacos , Eugenol/química , Eugenol/farmacologia , Listeria/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Monoterpenos/química , Monoterpenos/farmacologia , Fenol/síntese química , Fenol/química , Salmonella typhimurium/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Timol/química , Timol/farmacologia
8.
J Environ Manage ; 166: 429-39, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26555099

RESUMO

Searches related to global warming have provided important insights into the response of terrestrial ecosystems, but few have examined the impacts on agricultural crops, particularly those associated with the monitoring of agrotoxin residues. In this context, the agriclimatological zoning is an important tool in the planning and consolidation of crops and should be considered in any initiative that involves such planning. This tool is particularly important in the analysis of agrotoxin residues and may be applied by the Program Analysis of Agrotoxin Residues in Food (PARA) created by the National Health Vigilance Agency of Brazil (ANVISA), which enables greater food security and contributes to the improvement of human health. The aim of this study was to elaborate the current and future agriclimatological zoning for the tomato crop, relating it with the monitoring of samples collected by PARA in Espírito Santo State, Brazil. The results indicate that a temperature increase of 5 °C creates a decrease in apt areas from 37.3% to 4.3%, for a total reduction of 33 percentage points (-88.5%). It is noted that of the 41 producing municipalities, only 26 have apt areas greater than 50%, highlighting the municipalities with apt areas greater than 90%, represented by Mantenópolis (100%), Guaçuí (98.5%), São José do Calçado (97.8%), Irupi (94.4%), Santa Teresa (92.3%), and Marechal Floriano (91.4%). The veracity of agriclimatological zoning is proved by a Kendall rank correlation coefficient of 0.876, indicating that the distribution of the variables of apt areas and productivity are similar at the significance level of 0.05 with a confidence interval 95%. After validation of the agriclimatological zoning for the tomato crop, it is recommended that the PARA should monitor 36 municipalities rather than the current 18, representing an increase of 100%. The methodology can be adjusted to agricultural crops of other countries.


Assuntos
Produtos Agrícolas , Contaminação de Alimentos/análise , Sistemas de Informação Geográfica , Solanum lycopersicum , Brasil , Ecossistema , Monitoramento Ambiental , Análise de Alimentos/métodos , Aquecimento Global
9.
Bol. Centro Pesqui. Process. Aliment ; 27(1): 1-10, jan.-jun. 2009. ilus, graf, tab
Artigo em Português | LILACS | ID: lil-530585

RESUMO

Este trabalho teve como objetivo analisar a pervaporação para a recuperação e concentração de compsotos do aroma da bebida de café torrado e moído. Utilizou-se café torrado e moído de marca comercial como matéria-prima e membrana de etileno-propileno-dieno na pervaporação. O perfil aromático da bebioda de café e do concentrado aromático foi caracterizado por cromatografia a gás e espectrometria de massa. O bteve-se extrato concentrado dos componentes do aroma de café, indicando que a pervaporação é capaz de concentrar o aroma da bebida de café. A membrana constituída pelo terpolímero etileno-propileno-dieno apresentou bom desempenho nesse processo.


Assuntos
Cromatografia , Coffea Cruda , Tecnologia de Alimentos
10.
Ciênc. agrotec., (Impr.) ; 31(6): 1624-1629, nov.-dez. 2007. graf, tab
Artigo em Português | LILACS | ID: lil-471675

RESUMO

Objetivou-se neste trabalho avaliar o crescimento vegetativo e a produtividade de cafeeiros conilon (Coffea canephora Pierre ex Froehner), oriundos de mudas produzidas por estacas plantadas inicialmente em tubetes plásticos de 50 cm³ de capacidade. O experimento foi constituído de cinco tratamentos, que corresponderam aos tempos de permanência das estacas nos tubetes: 0; 15; 30; 45 e 60 dias. Transcorridos esses tempos as mudas foram, sucessivamente, transplantadas para sacos de polietileno, contendo mistura de terra, esterco de curral e adubo químico, enviveiradas em um viveiro coberto com sombrite (50 por cento), provido de micro aspersão automática. As mudas permaneceram no viveiro com micro aspersão automática por 150 dias, quando então foram transferidas para o viveiro de aclimatação, onde ficaram por mais 30 dias. Após esse período, em setembro de 1999, as mudas foram plantadas em condições de campo, na área experimental do CCA-UFES, em Alegre, Sul do Estado do Espírito Santo. Foram feitas as seguintes medições: crescimento de ramos ortotrópicos e plagiotrópicos no segundo ano após o plantio e as quatro primeiras colheitas. A produção inicial de mudas de café conilon em tubetes não afetou o crescimento vegetativo, tampouco a produção de frutos.


The objective of this work was to evaluate the vegetative growth and productivity of conilon coffee-tree (Coffea canephora Pierre ex Froehner), proceeding from seedlings produced of deep-rooted cuttings initially in plastic tubes with capacity of 50 cm³. The treatments were constituted of permanence period in plastic tube for 0; 15; 30; 45 and 60 days. After these periods the plants were transplanted for polyethylene bags filled with substrate (soil + sand + manure bovine and chemical fertilization) maintained on the greenhouse with environment under shading canvas (50 percent) and automatic micro aspersion during 150 days. After this time the plants were maintained during 30 days in acclimatization greenhouse management. Field experiment was set up in September of 1999, at experimental area CCA-UFES, in Alegre, south state of the Espírito Santo, Brasil. The following measurements were made: length of orthotropic and plagiotropic branches after first year and the first four productions. The results showed there were no differences either in vegetative growth and fruits production.

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