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1.
Biomed Chromatogr ; 34(1): e4712, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31633799

RESUMO

Coffee and tea are the most widely consumed beverages worldwide. However, the consumer may be unaware of the exact amount of methyl xanthine (MX, i.e. caffeine [C], theobromine [TB] and theophylline [TH]) consumed, as most of the products do not list the proper amounts. This may lead to serious risks including cardiovascular, kidney and stimulant effects. The aim of the study was to determine the MX amount in ready-to-use beverages (coffee and tea) collected from various outlets in the city of Al-Khobar, Saudi Arabia. Forty different samples of espresso, black coffee and red tea were collected. A fast, reliable and efficient UHPLC-DAD method was developed and validated for MX determination. Total lipids were extracted and fractionated in order to determine glycolipids, phospholipids and neutral lipids. The r2 value for the method was 0.980-0.988 in a linearity range of 0.5-200 ppm. The range for MX (C [0.02-2.39 mg/ml], TB [0.00-0.10 mg/ml] and TH [0.00-0.004 mg/ml]) and total lipids was 1-5 g. The amount of glycolipids (3.1 g) was higher among the lipid fractions followed by phospholipids (1.8 g) and neutral lipids (0.25 g). In general, espresso beverages (20-30 ml) contained high amounts of MX whereas black coffee beverages contained high amount of lipids. Most of the beverages expressed C, TB, TH, lipids or their fractions; however, the product with high amounts of MX and lipids at the same time was espresso (brands Chemistry and Wogard). Although the MX and lipid levels in these beverages well below the allowed limits, care must still be taken, especially when using the beverages with high serving volumes (200-250 ml) or coffee prepared via the filter method i.e. black coffee, using a high temperature for a longer time.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Café/química , Chá/química , Xantinas , Culinária , Temperatura Alta , Lipídeos/análise , Reprodutibilidade dos Testes , Arábia Saudita , Xantinas/análise , Xantinas/química , Xantinas/isolamento & purificação
2.
Food Chem ; 302: 125370, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31442699

RESUMO

Four Arabica coffees (Brazil, Colombia, Ethiopia, and Guatemala) yield highly variant odours, attesting to the complexities of coffee aroma that command advanced analytical tools. In this study, their volatiles were extracted using solvent-assisted flavour evaporation (SAFE) and headspace solid-phase microextraction (HS-SPME). Due to matrix complexity, some trace odourants were detected in SAFE extracts by aroma extract dilution analysis (AEDA) but remained difficult to quantify by gas chromatography-mass spectrometry (GC-MS). This prompted the application of low energy electron ionisation (EI) coupled with GC-quadrupole time-of-flight (GC-QTOF). Optimal low EI GC-QTOF parameters (EI energy: 15 eV, acquisition rate: 3 Hz) were applied to achieve improved molecular ion signal intensity and reproducibility (relative standard deviation < 10%) across five compounds, which resulted in good linearity (R2 ≥ 0.999) and lowered detection levels (e.g. 0.025 ±â€¯0.005 ng/mL for 4-hydroxy-5-methyl-3(2H)-furanone). Therefore, this method potentially improves the measurement of trace odourants in complex matrices by increasing specificity and sensitivity.


Assuntos
Café/química , Análise de Alimentos/métodos , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Adulto , Brasil , Coffea/química , Colômbia , Etiópia , Feminino , Análise de Alimentos/estatística & dados numéricos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Guatemala , Humanos , Masculino , Pessoa de Meia-Idade , Olfatometria/métodos , Extratos Vegetais/química , Análise de Componente Principal , Reprodutibilidade dos Testes , Microextração em Fase Sólida/métodos , Paladar , Compostos Orgânicos Voláteis/isolamento & purificação
3.
Food Chem ; 302: 125345, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31445377

RESUMO

This paper compares the results of standard chemical analytical processes and electrochemical impedance spectroscopy (EIS) in the characterization of different beverages, namely ground coffee, soluble coffee, coffee substitutes, barley, cow milk, vegetable drinks, tea, plant infusions and plant mixtures. For the two approaches, the similarities between the experimental data are assessed by means of the Euclidean and Canberra distances. The resulting information is processed by means of the multidimensional scaling (MDS) clustering and visualization algorithm. The results of the chemical analytical processes and EIS reveal identical clusters for the two adopted distances. Furthermore, the robustness of the experimental and computational scheme are assessed by means of the Procrustes technique. The results confirm the effectiveness of combining the EIS and MDS.


Assuntos
Bebidas/análise , Visualização de Dados , Espectroscopia Dielétrica/métodos , Algoritmos , Animais , Técnicas de Química Analítica/métodos , Análise por Conglomerados , Café/química , Espectroscopia Dielétrica/estatística & dados numéricos , Análise de Alimentos/métodos , Análise de Alimentos/estatística & dados numéricos , Leite/química , Processamento de Sinais Assistido por Computador , Chá/química
4.
Food Chem ; 303: 125372, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31446360

RESUMO

The formation and partial degradation of acrylamide (AA), asparagine and low molecular weight sugars were evaluated during an industrial coffee roasting process, in which the temperature increased from 90° to about 215 °C. Arabica and Robusta varieties were roasted individually. AA content reached the maximum value at 10 min, corresponding to a temperature of 175-177 °C (1045 ±â€¯28 and 795 ±â€¯25 µg kg-1 for Arabica and Robusta, respectively). Successively, AA content decreased very quickly and at 14 min (203-205 °C) its concentration was lower than the benchmark level of 400 µg kg-1 for roast coffee set by the EU Commission Regulation (2017/2158). In the final product, AA content was close to 300 µg kg-1. Asparagine quickly decreased; contrary, the concentration of fructose and glucose increased reaching their maximum value at 12 min. Then, a quick degradation occurred; their increase could be mainly due to the hydrolysis of sucrose, which decreased in the same period.


Assuntos
Acrilamida/análise , Café/química , Manipulação de Alimentos , Temperatura Alta , Asparagina/química , Sacarose , Açúcares/química
5.
J Agric Food Chem ; 67(50): 13775-13777, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31779309

RESUMO

The Second International Flavor and Fragrance Conference was successfully held on May 28-31, 2018, in Wuxi, China. The congress shared the progresses and discoveries in the research areas of flavor and fragrance perception, flavor analysis, thermal and biomediated generation of flavor, biological activities of aroma and flavor, and flavor and fragrance encapsulation and delivery technologies. This special issue collected some original research papers as well as reviews on basic taste, flavor analysis, aroma and taste characterization, essential oil bioactivity, and other related topics.


Assuntos
Aromatizantes/química , Odorantes/análise , Animais , Café/química , Humanos , Alimentos Marinhos/análise , Tetraodontiformes , Vinho/análise
6.
J Food Sci ; 84(11): 3099-3108, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31645089

RESUMO

In this work, different chemometric tools were compared to classify n = 26 conventional (CONV) and n = 19 organic (ORG) coffees from the main Brazilian producing regions based on the chemical composition, physicochemical properties, and antioxidant activity. Principal component analysis separated ORG and CONV coffees but the distinction among the producing regions of Brazilian coffee was not possible. Partial least squares discriminant analysis classified all ORG and CONV coffees in the external validation. Similarly, linear discriminant analysis was able to discriminate 100% and 81% of ORG and CONV coffees in the external validation, respectively, in which total phenolic content (TPC), ferric reducing antioxidant activity, and caffeic acid were the main discriminant variables. Overall 100% of samples from Paraná, Minas Gerais, and blended samples were correctly classified, where TPC, flavonoids, inhibition of lipid peroxidation, caffeic acid, pH, and soluble solids were the main discriminant variables. Support vector machines classified 95% ORG and 88% CONV, 100% Coffea arabica, and 88% and 78% coffees produced in São Paulo and Minas Gerais. k-Nearest neighbors was effective in distinguishing 100% CONV, 89% ORG, 100% coffees from São Paulo, and 100% C. arabica coffees. Overall, HPLC data and simple physicochemical parameters allied to chemometrics were effective in authenticating the cultivation system and the botanical origin of Brazilian coffees. PRACTICAL APPLICATION: Coffee adulteration is a serious problem in the food chain as some fraudsters replace coffee powder by other cheaper products. In the case of organic coffee, this scenario is even worse as still there is not a universal method to differentiate conventionally grown coffee from its organic counterpart. In addition, Brazilian coffee is produced in different regions and the commercial value varies. Therefore, we analyzed some physicochemical, chemical, and antioxidant properties of Brazilian coffees from distinct origins and classified the samples using chemometrics. Our approach seems to be interesting for quality control purposes.


Assuntos
Coffea/química , Café/química , Contaminação de Alimentos/análise , Antioxidantes/análise , Antioxidantes/farmacologia , Brasil , Ácidos Cafeicos/análise , Fenômenos Químicos , Análise Discriminante , Flavonoides/análise , Concentração de Íons de Hidrogênio , Análise dos Mínimos Quadrados , Fenóis/análise , Análise de Componente Principal , Sementes/química
7.
Artigo em Inglês | MEDLINE | ID: mdl-31584863

RESUMO

In the period from 2007 to 2017 furan levels of foods were analysed by the Austrian Agency for Health and Food Safety. Based on these analytical data and the Austrian consumption data the dietary exposure of children and adults to furan was estimated by using a deterministic approach. For the adult population the mean and 95th percentile dietary exposures to furan were estimated at 0.31 µg/kg bodyweight per day and at 0.72 µg/kg bodyweight per day, respectively. The mean dietary exposure of children was estimated at 0.18 µg/kg bodyweight per day and is thus only about half as high as for Austrian adults. At the 95th percentile the dietary exposure of children was estimated at 0.49 µg/kg bodyweight per day. The main contributor to the total dietary exposure for adults is coffee followed by convenience products and for children the main contributors are grain products as well as convenience products, bread and snacks. Based on the BMDL10 of 0.064 mg/kg bodyweight per day for the development of cholangiofibrosis, the MOE-calculation revealed that the current levels of dietary exposure to furan are of concern for Austrian adult high consumers. The MOE-calculation, based on the BMDL10 of 1.31 mg/kg bodyweight per day for the development of hepatocellular adenomas, indicated a health concern for Austrian children and adults.


Assuntos
Exposição Dietética/análise , Contaminação de Alimentos/análise , Furanos/análise , Adulto , Áustria , Criança , Café/química , Grão Comestível/química , Humanos
8.
J Food Sci ; 84(10): 2983-2994, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31518452

RESUMO

The aim of this study was to monitor and characterize Greek coffee staling during home storage (secondary shelf life, SSL) using sensory evaluation techniques. Storage temperature (T) and product water activity (aw ) are considered as the major factors affecting SSL. Water sorption isotherms fitted to Guggenheim Anderson-de Boer model were used to predict product stability; coffee samples were stable at aw < 0.52. Coffee samples equilibrated at aw = 0.15 (the fresh sample), 0.22, 0.33, and 0.52 were stored at T = 25 °C, 35 °C, and 45 °C under simulated home storage conditions. Samples were obtained at appropriate times for each T and aw condition and sensorially evaluated. Greek coffee brews were prepared and freshly served during sensory evaluation. The use of Weibull hazard analysis provided an effective approach to SSL determination as a function of T and aw . SSL values ranged from 20 (Τ = 45 °C, aw = 0.52) to 104 days (Τ = 25 °C, aw = 0.15). Quality loss based on coffee aroma changes (aroma quality, aroma intensity, aftertaste, off-flavor) was also studied (Si , sensory scoring using 9-point magnitude scale) and kinetically modeled. Quality loss rates (ki ) were calculated and used to predict SSL values. Based on the results of both Weibull hazard analysis and sensory scoring of individual aroma characteristics, it was concluded that the lowest SSL was calculated for aw = 0.52 at T = 35 °C to 45 °C. The temperature dependence of aftertaste, aroma quality loss, and off-flavor production was not statistically significant for 0.15 < aw < 0.33 (P > 0.05); the aroma intensity was the most sensitive parameter. PRACTICAL APPLICATIONS: Secondary shelf life (SSL) represents the time after pack opening during which a food maintains an acceptable quality level. During home/catering usage, coffee is not consumed immediately after pack opening. During consumption, quality degradation reactions proceed with higher rates due to variable storage conditions mainly related to atmosphere changes in the pack, leading to the entrance of oxygen/moisture and temperature. Therefore, SSL is important, and can be used as a tool for product management during consumption reducing food waste. There is a lack of studies dealing with SSL prediction of coffee, while no studies have been carried out on Greek coffee.


Assuntos
Café/química , Água/química , Adulto , Culinária , Feminino , Aromatizantes/análise , Armazenamento de Alimentos , Grécia , Humanos , Masculino , Pessoa de Meia-Idade , Odorantes/análise , Paladar , Temperatura Ambiente , Adulto Jovem
9.
J Agric Food Chem ; 67(39): 10921-10929, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31496242

RESUMO

Free amino residues react with α-dicarbonyl compounds (DCs) contributing to the formation of advanced glycation end products (AGEs). Phenolic compounds can scavenge DCs, thus controlling the dietary carbonyl load. This study showed that high-molecular weight cocoa melanoidins (HMW-COM), HMW bread melanoidins (HMW-BM), and especially HMW coffee melanoidins (HMW-CM) are effective DC scavengers. HMW-CM (1 mg/mL) scavenged more than 40% DCs within 2 h under simulated physiological conditions, suggesting some physiological relevance. Partial acid hydrolysis of HMW-CM decreased the dicarbonyl trapping capacity, demonstrating that the ability to react with glyoxal, methylglyoxal (MGO), and diacetyl was mainly because of polyphenols bound to macromolecules. Caffeic acid (CA) and 3-caffeoylquinic acid showed a DC-scavenging kinetic profile similar to that of HMW-CM, while mass spectrometry data confirmed that hydroxyalkylation and aromatic substitution reactions led to the formation of a stable adduct between CA and MGO. These findings corroborated the idea that antioxidant-rich indigestible materials could limit carbonyl stress and AGE formation across the gastrointestinal tract.


Assuntos
Pão/análise , Cacau/química , Café/química , Diacetil/química , Depuradores de Radicais Livres/química , Extratos Vegetais/química , Polímeros/química , Cacau/metabolismo , Café/metabolismo , Diacetil/metabolismo , Depuradores de Radicais Livres/metabolismo , Trato Gastrointestinal/metabolismo , Glioxal/química , Humanos , Modelos Biológicos , Extratos Vegetais/metabolismo , Polímeros/metabolismo , Aldeído Pirúvico/química , Aldeído Pirúvico/metabolismo
10.
Phytother Res ; 33(11): 2918-2926, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31429515

RESUMO

Given the proliferation in studies investigating green coffee bean extract (GCBE) supplementation, the purpose of this study was to determine the efficacy and effectiveness of GCBE supplementation on indices of blood pressure. The literature search was performed in four databases, namely, PubMed/Medline, Scopus, the Cochrane Library, and Google Scholar, to identify clinical trials that examined the effects of green coffee supplements on systolic blood pressure (SBP) and diastolic blood pressure (DBP) up to February 2019. Mean change and standard deviation (SD) of the outcome measures were used to estimate the mean difference between the intervention group and the control group at follow-up. Nine studies reported SBP and DBP as an outcome measure. Results revealed significant reduction in SBP (weighted mean difference: -3.093 mmHg, 95% confidence interval [CI]: -3.914, -2.273; I2 = 0.0%) and DBP (-2.170 mmHg, 95% CI: -2.749, -1.590; I2 = 46.5%) after green coffee supplementation with low heterogeneity among the studies. In addition, in subgroup analysis, a significant reduction in SBP and DBP in studies with hypertensive patients, green coffee dosage <400 mg, and administered for 4 weeks was identified. The results of the current meta-analysis study support the use of GCBE supplementation for the improvement of blood pressure indices, with subgroup analysis highlighting improvements in hypertensive patients.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Café/química , Extratos Vegetais/farmacologia , Suplementos Nutricionais , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Extratos Vegetais/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos
11.
J Food Sci ; 84(9): 2628-2637, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31441950

RESUMO

Several factors have led to an increase in the consumption of sweeteners in substitution of sucrose. Studies on the behavior and the sensory properties of sweeteners are relevant, once they provide knowledge about both the adequate sweetener concentration with a sweetness equivalence to a sucrose-sweetened product and the possible sensory changes of the product. The addition of stevia with different rebaudioside A concentrations and sucralose to traditional and decaffeinated espresso coffee was studied, using the just-about-right scale and magnitude estimation method, to determine the ideal sweetness and the acceptance of the samples. The effect of the intensity of sensory attributes sweet taste, bitter taste, coffee flavor, and body in the acceptance was evaluated by penalty analysis. Decaffeinated presented proportionally lower sucrose concentration and sweetness equivalence than the traditional samples. Stevia concentrations were similar, despite the different rebaudioside A concentrations, for both traditional and decaffeinated samples, and rebaudioside A levels from stevia in espresso have no differences in sweetness intensity. Sucralose was the most intense sweetener in espresso. Although no differences were observed in the acceptance test in relation to appearance, aroma, and texture among the samples, the internal preference map showed segmentation of consumers with respect to the acceptability. This segmentation is more related to the type of sample than the added sweetener. Penalty analysis demonstrated that the most penalizing sensory characteristics were "coffee flavor" and "sweet," leading to a significant decrease in the acceptability of the samples. PRACTICAL APPLICATION: Conclusions obtained are important source of knowledge for the coffee industry, in the development and manufacture of beverages with coffee. The present findings can help to understand the behavior and the sensory properties of sweeteners. They provide knowledge about sensory perception of sweet and bitter tastes, and the factors that influence this perception and the sensory profile of the samples, once the behavior of sweeteners varies according to the product to which they are added.


Assuntos
Café/química , Preferências Alimentares , Edulcorantes/análise , Adulto , Diterpenos de Caurano/análise , Feminino , Glucosídeos/análise , Humanos , Masculino , Pessoa de Meia-Idade , Sacarose/análise , Paladar , Adulto Jovem
12.
Food Chem ; 301: 125187, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31387041

RESUMO

Solid and liquid components coexist into glassy and amorphous structures of food complex matrixes. Both states admit movements, promoting physical modifications to a more thermodynamically stable system. Green and roasted coffee beans are principally characterized by a glassy structure that slowly evolves during storage. The aim of this study was to assess calorimetric and dielectric properties in combination, as a useful multi-analytical technique to improve the understanding of the motion mechanism of localized molecules. After equilibration at different water activities (aw) for the determination of sorption isotherms of green and roasted coffee, the glass transition temperature (Tg) of the samples has been measured by using differential scanning calorimetry (DSC). Increasing the aw from 0.155 to 0.512, the Tg shifted from 48.76 (±0.04) to 34.89 (±0.02) °C for green coffee and from 45.73 (±0.05) to 40.15 (±0.10) °C for the roasted one. The spectroscopic fingerprint of the matrix has been determined by dielectric measurements in terms of "gain" spectra (related to the imaginary part of permittivity). The maximum values of the determination coefficient (R2), obtained by linear correlation between spectral data and water activity or glass transition values for a specific frequency of the whole range (1.6 GHz-2.7 GHz), were 0.999 and 0.943 for green, and 0.997 R2 and 0.925 R2 for roasted coffee respectively.


Assuntos
Coffea/química , Café/química , Varredura Diferencial de Calorimetria , Temperatura de Transição , Vitrificação , Água/química
13.
Molecules ; 24(17)2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31461962

RESUMO

This work investigates the feasibility of using coffee silverskin (CSS) as a reinforcing agent in biobased polyethylene (BioPE) composites, by adding it in bulk and thin film samples. The effect of two different treatments, alkali bleaching (CSS_A) and esterification with palmitoyl chloride (CSS_P), on mechanical, thermal, morphological and water absorption behavior of produced materials at different CSS loading (10, 20 and 30 wt %) was investigated. A reactive graft copolymerization of BioPE with maleic anhydride was considered in the case of alkali treated CSS. It was found that, when introduced in bulk samples, improvement in the elastic modulus and a reduction in strain at maximum stress were observed with the increase in CSS fraction for the untreated and treated CSS composites, while the low aspect ratio of the CSS particles and their poor adhesion with the polymeric matrix were responsible for reduced ductility in films, decreasing crystallinity values and reduction of elastic moduli. When CSS_A and CSS_P are introduced in the matrix, a substantial reduction in the water uptake is also obtained in films, mainly due to presence of maleated PE, that builds up some interactions to eliminate the amounts of OH groups and hydrophobized CSS, due to the weakened absorption capacity of the functionalized CSS.


Assuntos
Café/química , Anidridos Maleicos/química , Palmitatos/química , Módulo de Elasticidade , Esterificação , Estudos de Viabilidade , Teste de Materiais , Propriedades de Superfície
14.
Food Chem ; 301: 125250, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31377616

RESUMO

Untargeted LC/MS flavoromic profiling was utilized to identify compounds that positively impact coffee quality. The chemical profiles of eighteen coffee samples and the corresponding Specialty Coffee Association (SCA) cup scores were modeled by orthogonal partial least squares (OPLS) analysis with good fit and predictive ability (R2Y > 0.9, Q2 > 0.9). Four highly predictive chemical compounds positively correlated to cup score were subsequently isolated and purified (>90%) by multi-dimensional preparative LC/MS fractionation. Sensory recombination analysis by certified SCA Q-graders (n = 5) confirmed three out of four compounds significantly increased cup score when added to a control coffee (p < 0.001). Based on accurate mass spectrometry and NMR experiments, the compound structures were identified as novel compounds 3-O-caffeoyl-4-O-3-methylbutanoylquinic acid, and the corresponding lactone 3-O-caffeoyl-4-O-3-methylbutanoyl-1,5-quinide, as well as an unknown phenolic derivative containing a 3-methylbutanoyl moiety ([M-H]-1, m/z 671). No direct flavor activity was observed for each compound, indicating these compounds act as flavor-modifiers.


Assuntos
Café/química , Qualidade dos Alimentos , Paladar , Cromatografia Líquida , Lactonas/análise , Análise dos Mínimos Quadrados , Espectrometria de Massas
15.
Food Chem ; 301: 125264, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31377623

RESUMO

A straightforward and rapid preparation procedure for the extraction of the acrylamide from coffee beans, by means of the volatile silylated derivatives of acrylamide (AA) and headspace solid phase microextraction (HS-SPME) is described. Commercially available SPME fibre coated with polydimethylsiloxane (PDMS) was used. The silylation reactions of the AA were executed with N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA). The deuterium labelled d3-acrylamide was used as an internal standard. The acrylamide level was quantified using gas chromatography coupled with the mass spectrometry (GC-MS) in the selected ion monitoring (SIM) mode. The limit of quantification (LOQ) for measuring acrylamide was 3 µg/kg. The described method demonstrates satisfactory repeatability (RSD = 2.6%), with an intermediate precision (RSD = 9.4%) and recovery (99-105%).


Assuntos
Acrilamida/análise , Coffea/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Sementes/química , Microextração em Fase Sólida/métodos , Café/química , Dimetilpolisiloxanos
16.
Fungal Biol ; 123(8): 611-617, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31345415

RESUMO

The current investigation was aimed to estimate the prevalence and concentration of ochratoxin A (OTA) in different types of coffee and coffee-based products with the aid of a systematic review and meta-analysis. Therefore, the recommended databases including PubMed, Scopus, and Embase from Jan 1983 to Oct 2018 were screened to retrieve the related citations. In this regard, among 1041 explored articles in the identification step, thirty six articles with 3182 samples were included in the meta-analysis and meta-regression. According to findings, the global pooled concentration and prevalence of OTA was calculated as 3.21 µg/kg (95% CI: 3.08-3.34 µg/kg) and 53.0 % (95% CI: 43.0-62.0), respectively. Also, direct correlations between the increases in poverty as well as the amount of annual precipitation and prevalence of OTA was noted, while with decreasing in HDI the prevalence of OTA in coffee significantly was increased. Moreover, the lowest and highest concentrations of OTA in coffee were observed in Taiwan (0.35 µg/kg) and Turkey (79.0 µg/kg), respectively. The outcome of this meta-analysis can be used for the building of risk assessment models aiming to derive data for the development of specific actions to reduce the exposure to this mycotoxin in coffee and coffee-based products.


Assuntos
Coffea/química , Café/química , Contaminação de Alimentos/estatística & dados numéricos , Ocratoxinas/análise , Contaminação de Alimentos/análise , Sementes/química
17.
Environ Sci Pollut Res Int ; 26(26): 26529-26541, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31292868

RESUMO

The present study describes the impregnation of coffee extract (CE) into bacterial cellulose synthesized from kombucha tea fungus (KBC) of different cellulose content, incubated for different incubation periods (2, 4, and 10 days), to prepare biocomposites having the potential for wound healing applications. Total polyphenols in hydroalcoholic extracts from ground roasted coffee and its release from the prepared biocomposites were determined as gallic acid equivalent. The polyphenols content was found to be 13.66 mg/g and the minimum inhibitory concentration (MIC) of the CE was determined using colony-forming unit (CFU) method against Gram-negative bacteria Escherichia coli and Gram-positive bacteria Staphylococcus aureus where the growth inhibition was 86 and 97% respectively. Biocomposites (KBC/CE) with the lowest cellulose and CE content showed the highest wet tensile stress (3.35 MPa), absorption of pseudo extracellular fluid (154.32% ± 4.84), and water vapor transmission rate (3184.94 ± 198.07 g/m2/day), whereas it showed the lowest polyphenols' release (51.85% ± 2.94)when immersed in PBS buffer of pH 7.4. The impregnation of CE into KBC provided biocomposites that can enlarge the range of BC in the biomedical application.


Assuntos
Antibacterianos/farmacologia , Celulose/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Cicatrização/efeitos dos fármacos , Bandagens , Café/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Chá de Kombucha , Testes de Sensibilidade Microbiana
18.
Food Chem Toxicol ; 132: 110672, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31306686

RESUMO

The aim of this study was to evaluate the inhibitory potential of aqueous extracts from coffee silverskin (CSE) and husk (CHE) and their main phenolics on adipogenesis, obesity-related inflammation, mitochondrial dysfunction, and insulin resistance, in vitro. Coffee by-products extracts (31-500 µg mL-1) and pure phenolics (100 µmol L-1) reduced lipid accumulation and increased mitochondrial activity in 3T3-L1 adipocytes. Also reduced the expression of inducible nitric oxide synthase and cyclooxygenase-2 and diminished secretion of pro-inflammatory factors in LPS-stimulated RAW2643.7 macrophages. Cytokine release diminished (tumor necrosis factor α: 23-57%; monocyte chemoattractant protein 1: 42-60%; interleukin-6: 30-39%) and adiponectin increased (7-13- fold) in adipocytes treated with macrophage-conditioned media. ROS scavenging and activation of peroxisome proliferator-activated receptor γ coactivator 1-α pathway counteracted mitochondrial dysfunction. Increases in insulin receptor (1.4 to 4-fold), phosphoinositide 3-kinase (2 to 3-fold) and protein kinase B (1.3 to 3-fold) phosphorylation, in conjunction with a decrease in serine phosphorylation of insulin receptor substrate 1, evoked glucose transporter 4 translocation (8-15-fold) and glucose uptake (44-85%). CSE and CHE phenolics inhibited adipogenesis and elicited adipocytes browning. Suppressing macrophages-adipocytes interaction alleviated inflammation-triggered mitochondrial dysfunction and insulin resistance. CSE and CHE are beneficial in reducing adipogenesis and inflammation-related disorders.


Assuntos
Adipogenia/efeitos dos fármacos , Café/química , Inflamação/patologia , Resistência à Insulina , Mitocôndrias/efeitos dos fármacos , Fenóis/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Meios de Cultivo Condicionados , Camundongos , Mitocôndrias/fisiologia , Fenóis/isolamento & purificação , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo
19.
J Chromatogr A ; 1605: 360353, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31307792

RESUMO

The aim of this work was to develop a capillary electrophoresis-mass spectrometry (CE-ESI-QToF-MS) method to carry out the metabolic fingerprinting of green and roasted coffee samples (Arabica variety). To evaluate changes in the metabolic profiles of coffee occurring along the roasting process, green coffee beans were submitted to different roasting degrees. The effect of different parameters concerning the electrophoretic separation (background electrolyte, temperature, voltage, and injection time), the MS detection (temperature and flow of drying gas, sheath gas of jet stream temperature, and capillary, fragmentator, nozzle, skimmer, and octapole voltages) and the sheath liquid (composition and flow rate) was studied to achieve an adequate separation and to obtain the largest number of molecular features. The analyses were carried out in positive ESI mode allowing to detect highly polar cationic metabolites present in coffee beans. Non-supervised and supervised multivariate analyses were performed showing a good discrimination among the different coffee groups. Those features having a high variable importance in the projection values on supervised analyses were selected as significant metabolites for their identification. Thus, 13 compounds were proposed as potential markers of the coffee roasting process, being 7 of them tentatively identified and 2 of them unequivocally identified. Different families of compounds such as pyridines, pyrroles, betaines, or indoles could be pointed out as markers of the coffee roasting process.


Assuntos
Café/química , Café/metabolismo , Eletroforese Capilar/métodos , Metabolômica/métodos , Espectrometria de Massas em Tandem/métodos , Coffea/química , Análise Discriminante , Análise dos Mínimos Quadrados , Metaboloma , Análise de Componente Principal
20.
J Food Sci ; 84(8): 2297-2312, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31269246

RESUMO

In this work, discrimination tests, descriptive analysis, consumer tests, and total dissolved solids (TDS) were used to evaluate the effects of brew basket geometry on the sensory quality and consumer acceptance of drip brewed coffee. Two basic geometries, semi-conical and flat-bottom, were evaluated in conjunction with coffee roast and particle size. Initial discrimination tests showed that small differences in median particle size were not discernable, but that coffees brewed using either semi-conical or flat-bottom filter baskets were significantly different (P < 0.05, N = 45). Additionally, coffee brewed in the semi-conical basket had significantly higher %TDS, and we estimated a sensory difference threshold of 0.24 %TDS. A subsequent descriptive analysis (DA) showed significant differences by roast for 11 attributes and by grind for six attributes. Although brewing geometry, as a single factor, was only significantly different for three independent attributes (smoke aroma, sweetness, and tobacco flavor), roast × geometry interactions were significant for six attributes (berry flavor, bitterness, burnt wood/ash, citrus flavor, earthy flavor, and sourness) and the grind × geometry interaction was significant for two attributes (bitterness and floral aroma). Attributes showing significant interactions with brewing geometry were also key drivers of consumer liking/disliking. Overall consumer liking (9-point hedonic scale) was analyzed by cluster analysis (N = 85), which revealed four distinct preference clusters. For each cluster, a particular basket geometry and/or roast level showed lesser acceptance. Overall, the results strongly corroborate the hypothesis that basket geometry affects the sensory quality of drip brewed coffee. PRACTICAL APPLICATION: Most Americans consume drip brewed coffee. Improving our understanding of the effects of basket geometry, roast level, and grind size on the total dissolved solids, sensory properties, and acceptability of drip brewed coffee gives producers and consumers alike an opportunity to optimize the sensory quality of their coffee.


Assuntos
Café/química , Culinária/instrumentação , Preferências Alimentares , Paladar , Análise por Conglomerados , Coffea/química , Café/metabolismo , Comportamento do Consumidor , Culinária/métodos , Aromatizantes/análise , Humanos , Odorantes/análise , Sementes/química
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