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1.
J Agric Food Chem ; 67(37): 10352-10360, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31503479

RESUMO

The potential for apple peels to mitigate the deleterious effects of a high-fat diet in mice was investigated here. Mice were fed a high-fat diet supplemented with apple powders from three apple varieties or a commercial apple polyphenol. Polyphenols were characterized using colorimetric assays and high-performance liquid chromatography. Mice were tested for standard metabolic parameters. There was a dose response to dietary apple peels, with the higher intake leading to reduced weight gain and adipose tissue mass relative to the lower intake, but none of the treatments were statistically different from the control. The gene expression of liver enzyme stearoyl-CoA desaturase (Scd-1) was correlated with adipose weight, and liver enzyme cytochrome P51 (Cyp51) was downregulated by the apple diets. The feces from a subset of mice were analyzed for polyphenols and for bacteria taxa by next-generation sequencing. The results revealed that the makeup of the fecal microbiota was related to the metabolism of dietary polyphenols.


Assuntos
Biflavonoides/análise , Catequina/análise , Fezes/química , Frutas/metabolismo , Microbioma Gastrointestinal , Malus/metabolismo , Obesidade/dietoterapia , Proantocianidinas/análise , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biflavonoides/metabolismo , Catequina/metabolismo , Dieta Hiperlipídica/efeitos adversos , Frutas/química , Humanos , Masculino , Malus/química , Camundongos , Obesidade/genética , Obesidade/metabolismo , Obesidade/microbiologia , Polifenóis/análise , Polifenóis/metabolismo , Proantocianidinas/metabolismo , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo , Esterol 14-Desmetilase/genética , Esterol 14-Desmetilase/metabolismo
2.
Food Chem ; 301: 124590, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31398674

RESUMO

In this study the effect of agavin and inulin addition on the microstructural, textural, thermal and sensory properties of apple leathers was investigated. Agavins and inulin were added to leathers at two concentration levels (6 and 4%) individually and as a mixture. Scanning Electron Microscopy (SEM) revealed more compact and less porous matrices in the 6% concentration with respect to the control, influencing leather texture. In formulations with agavins the texture was significantly (p < 0.05) smoother than in those with inulin. No relationship was found between hardness and glass transition temperature (Tg), but there was a significant difference between treated leathers and the control. The acceptability of the product showed a direct relationship with the hardness. There were significant changes in the leathers after storage. Agavins and inulin exhibited different technological properties and considering the texturising effect of the agavins, their potential for use in the food industry is promising.


Assuntos
Inulina/química , Malus/química , Paladar , Agave/química , Indústria de Processamento de Alimentos , Humanos , Microscopia Eletrônica de Varredura , Prebióticos
3.
J Sci Food Agric ; 99(14): 6644-6648, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31325326

RESUMO

BACKGROUND: Apple juice is rich in polyphenolic compounds, especially in chlorogenic acid. A sour and bitter taste has been attributed to the compound. Chlorogenic acid in coffee powder was quickly hydrolysed by a p-coumaryl esterase of Rhizoctonia solani (RspCAE) at its optimal pH of 6.0. It was unknown, however, if RspCAE would also degrade chlorogenic acid under the strongly acidic conditions (pH 3.3) present in apple juice. RESULTS: Treatment of apple juice with RspCAE led to a chlorogenic acid degradation from 53.38 ± 0.94 mg L-1 to 21.02 ± 1.47 mg L-1 . Simultaneously, the caffeic acid content increased from 6.72 ± 0.69 mg L-1 to 19.33 ± 1.86 mg/L-1 . The aroma profile of the enzymatically treated sample and a control sample differed in only one volatile. Vitispirane had a higher flavour dilution factor in the treated juice. Sensory analysis showed no significant difference in the taste profile ( p < 0.05). CONCLUSION: These results demonstrated a high stability and substrate specificity of RspCAE. An increase in caffeic acid and a concurrent decrease in chlorogenic acid concentration may exert a beneficial effect on human health. © 2019 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Ácido Clorogênico/química , Esterases/química , Sucos de Frutas e Vegetais/análise , Proteínas Fúngicas/química , Malus/química , Rhizoctonia/enzimologia , Aromatizantes/química , Concentração de Íons de Hidrogênio , Hidrólise , Odorantes/análise , Especificidade por Substrato
4.
Anal Bioanal Chem ; 411(23): 6057-6066, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31278555

RESUMO

In this study, we report a direct surface plasmon resonance (SPR) biosensor based on an oriented assembly of antibody for the rapid detection of chlorpyrifos residue in agricultural samples. In this covalent-orientated strategy, staphylococcal protein A (SPA) was first covalently bound to the surface for monitoring chlorpyrifos residue, with subsequent binding of the antibody in an orientated fashion via its fragment crystallizable (Fc) region. Consequently, the SPA-modified biosensor exhibited a satisfactory specificity and a low detection limit of 0.056 ng mL-1 for chlorpyrifos, with a linear detection range of 0.25-50.0 ng mL-1. Under optimal conditions, the sensor chip could be regenerated for at least 210 cycles. The results presented here indicate that the SPA-modified sensor chip can successfully improve the sensitivity and obviating the need of the modification of the antibody. The developed SPR biosensor method has the great potential for rapid, sensitive, and specific detection with broad applications in areas of environmental monitoring and food safety. Graphical abstract.


Assuntos
Clorpirifos/análise , Análise de Perigos e Pontos Críticos de Controle/métodos , Inseticidas/análise , Proteína Estafilocócica A/química , Ressonância de Plasmônio de Superfície/métodos , Anticorpos Imobilizados/química , Brassica/química , Contaminação de Alimentos/análise , Imunoensaio/métodos , Limite de Detecção , Malus/química , Zea mays/química
5.
J Food Sci ; 84(8): 2147-2158, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31313833

RESUMO

Multiple analytical methods are used for quantification of total polyphenols and total flavanols in fruit juices and beverages. Four methods were evaluated in this study: Folin-Ciocalteu (F-C), Lowenthal permanganate (L-P), 4-dimethylaminocinnamaldehyde (DMAC), and the bovine serum albumin (BSA) precipitation method. Method validation parameters, including working range, limit of detection, limit of quantitation, precision (repeatability), accuracy, and specificity, were assessed and compared. The F-C method was not specific to polyphenols, and the L-P method had the widest working range but lacked accuracy. The DMAC method was the most specific to flavanols, and the BSA method was not suitable for quantification of smaller flavanols, such as catechin and epicatechin. Quantitative performance was evaluated using commercial fruit juice samples (n = 14), apple juice samples of different cultivars (n = 22), and commercial ciders (n = 17). In general, the L-P titration method and DMAC method resulted in higher quantitative values than the F-C method and BSA precipitation method, respectively. However, ratios of results obtained by the L-P and F-C method ranged from 1 to 28, and ratios of results obtained by the DMAC and BSA precipitation method ranged from <1 to 280. This tremendous variation is likely due to variation in polyphenol composition and sample matrix. This information provides perspective for comparison of results obtained through these different methods, and a basis for choosing the most appropriate analytical method for quantification of polyphenols to address a specific research question when working with commercial fruit juice, apple juice from different apple cultivars, and commercial ciders. PRACTICAL APPLICATION: This study compared results obtained when four common polyphenol quantification methods were applied to a diverse selection of fruit juices and beverages with distinct polyphenol composition and sample matrix. The matrix and polyphenol composition of the samples significantly influenced the results. Our findings can help manufacturers of fruit-based products choose the most appropriate analytical method for polyphenol quantification as part of a quality assurance program or to convey information on dietary polyphenol content to consumers. An assessment of analytical method validation parameters is provided for each of the four methods, which will help users of these methods to understand their limitations.


Assuntos
Flavanonas/análise , Análise de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Polifenóis/análise , Frutas/química , Malus/química
6.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(3): 209-214, 2019 May 28.
Artigo em Chinês | MEDLINE | ID: mdl-31257800

RESUMO

OBJECTIVE: To investigate the effects of apple polyphenols on pulmonary vascular remodeling in rats with pulmonary arterial hypertension and its mechanism. METHODS: Rats were randomly divided into 4 groups:control (Con) group, monocrotaline (MCT) group, apple polyphenol (APP) group,monocrotaline + apple polyphenol (MCT+APP) group. In Con group, rats received a subcutaneous injection of physical saline. In APP group, rats received intraperitoneal injection of 20 mg/kg APP, every other day. In MCT group, rats received a single subcutaneous injection of MCT(60 mg/kg). In MCT+APP group, rats received subcutaneous injection of 60 mg/kg MCT followed by an intraperitoneal injection of 20 mg/kg APP every other day. All the disposal lasted 3 weeks. Then the PAH-relevant indicators, such as mean pulmonary artery pressure(mPAP), pulmonary vascular resistance(PVR), right ventricular hypertrophy index (RVHI) ,wall thickness (WT%) and wall area (WA%) were tested. After that, the inflammatory pathway related indicators, such as interleukin1(IL-1),interleukin1(IL-6), tumor necrosis factor α(TNF-α), cyclooxygenase 2(COX-2) and myeloperoxidase(MPO) in pulmonary tissue and free intracellular Ca2+ in pulmonary smooth muscle cell(PASMC), content of eNOS and NO in endothelial cells were determined. RESULTS: Compared with the control group, the levels of mPAP, PVR, RVHI, WA%, WT%, and IL-1, IL-6, TNF-α, COX-2, MPO in tissue and the expression of Ca2 + in PASMC of MCT group were increased significantly, while the contents of eNOS and NO in endothelial cells were decreased significantly (P<0.05). Compared with the MCT group, the apple polyphenol treatment could improve the above mentioned situation, and the COX-2 and Ca2+ indicators of the apple polyphenol treatment group were decreased significantly (P<0.05). CONCLUSION: MCT can increase COX-2 expression and intracellular Ca2+ in pulmonary artery smooth muscle cells, decrease the contents of eNOS and NO in endothelial cells, while apple polyphenols can significantly inhibit these effects.


Assuntos
Malus/química , Polifenóis/farmacologia , Artéria Pulmonar/efeitos dos fármacos , Remodelação Vascular/efeitos dos fármacos , Animais , Cálcio/metabolismo , Ciclo-Oxigenase 2/metabolismo , Citocinas/metabolismo , Monocrotalina , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Artéria Pulmonar/patologia , Distribuição Aleatória , Ratos
7.
Food Chem ; 300: 125189, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31325754

RESUMO

Since the intake of quercetin glucosides has healthy benefits, the analysis of quercetin glucosides in food is useful. The electrochemical determination of individual quercetin glucosides (quercetin-3-glucoside (Q3G), quercetin-4'-glucoside (Q4'G), and quercetin-3,4'-diglucoside (Q34'G)) in food is carried out. For the detection of quercetin glucosides, a long-length carbon nanotube electrode offers attractive properties such as well-defined current peaks, high sensitivity, and high reproducibility. Cyclic voltammetry (CV) demonstrates distinct and specific peak currents: the oxidation peaks at +0.37, +0.45, and +0.78 V are assigned to the catechol group in the B-ring of Q3G, the 3-hydroxy group in the C-ring of Q4'G, and the resorcinol group in the A-ring of both Q4'G and Q34'G, respectively. Currents, which are determined by CV, of individual quercetin glucosides at the peak potential are proportional to the concentrations of onion, apple peel, and tartary buckwheat, which show good agreement with those obtained by high-performance liquid chromatography.


Assuntos
Técnicas Eletroquímicas/instrumentação , Eletrodos , Análise de Alimentos/métodos , Glucosídeos/análise , Quercetina/análise , Técnicas Eletroquímicas/métodos , Fagopyrum/química , Análise de Alimentos/instrumentação , Malus/química , Nanotubos de Carbono , Cebolas/química , Oxirredução , Quercetina/análogos & derivados , Quercetina/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
Plant Foods Hum Nutr ; 74(3): 430-435, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31302831

RESUMO

The beneficial health effects of apple consumption are well known, however, little is known about the potential of its phenolic fractions to inhibit α-glucosidases and thereafter to treat diseases related to the carbohydrate metabolism, such as postprandial hyperglycemia and diabetes. In the present study, the α-glucosidase inhibition and antioxidant activity of different phenolic fractions of apple were evaluated using the 2,2-diphenyl-1-picrylhydrazyl and hydroxyl radical scavenging activity. Moreover, the phenolic fractions were chemically characterized by LC-MS in order to identify the compounds responsible for the biological properties. The purified extract (not fractionated) had the highest α-glucosidase and hydroxyl radical inhibitions. The purified extract and fractions III and IV were more active against the enzyme activity than the positive control acarbose, the drug used by diabetic patients to treat postprandial hyperglycaemia. Our results show that apple phenolic extracts strongly inhibit α-glucosidase acitivity, validating their potential to be used in the management of type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores de Glicosídeo Hidrolases/farmacologia , Hiperglicemia/tratamento farmacológico , Malus/química , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Metabolismo dos Carboidratos , Fenóis/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/isolamento & purificação , alfa-Glucosidases/metabolismo
9.
J Agric Food Chem ; 67(31): 8599-8608, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31287302

RESUMO

Because foods are perceived through combined inputs from taste and odor, which are determined by the concentration of the individual odor and taste molecules, the unified high-throughput quantitation of volatile odorants and non-volatile tastants with the very same instrumental setup has been a long-standing but yet unmet dream. The research presented here for the first time demonstrates, after only minimal sample workup, the highly accurate, rapid, and sensitive unified quantitation of odorants and tastants of key flavor molecules in apple juice on a single ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) platform over a large dynamic range of up to 6 orders of magnitude. While flavor-active aldehydes, ketones, and organic acids were analyzed after derivatization with 3-nitrophenylhydrazine, taste-active polyphenols and odor-active esters were directly analyzed by means of UHPLC-MS/MS with and without target analyte enrichment through stir-bar sorptive extraction. This "unified flavor quantitation" approach holds promise to accelerate the transition of today's labor and time-consuming, low-throughput analysis of odorants and tastants into a new era of high-performance quantitation of key flavor molecules.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Aromatizantes/química , Ensaios de Triagem em Larga Escala/métodos , Odorantes/análise , Espectrometria de Massas em Tandem/métodos , Sucos de Frutas e Vegetais/análise , Malus/química , Compostos Orgânicos Voláteis/química
10.
Anal Chim Acta ; 1074: 131-141, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31159933

RESUMO

Semiconducting single-walled carbon nanotubes (s-SWCNTs) have been demonstrated as an excellent material for transistors, miniaturized devices and sensors due to their high carrier mobility, stability, scattering-free ballistic transport of carriers etc. Herein, we have designed a biosensor to selectively detect methyl parathion (MP, organophosphorus pesticide) using glutaraldehyde (Glu) cross-linked with acetylcholinesterase (AChE) immobilized on s-SWCNTs wrapped with bovine serum albumin (BSA). The fabricated biosensor was characterized and confirmed by Fourier-transform infrared spectroscopy (FT-IR), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and square wave voltammetry (SWV). In the presence of MP, the effective interaction between AChE and MP favours the accumulation of MP-AChE complex on the glassy carbon electrode (GCE) surface which reduces the electron transfer property. Based on this interaction, detection of various concentration of MP was demonstrated by SWV using BSA/AChE-Glu-s-SWCNTs composite modified electrode. The proposed biosensor exhibited a wide linear range (WLR) for MP target in 100 mM phosphate buffered saline solution (PBS) (pH 7.4) from 1 × 10-10 M to 5 × 10-6 M with a limit of detection (LOD) of 3.75 × 10-11 M. In addition, the BSA/AChE-Glu-s-SWCNTs/GCE biosensor showed good repeatability and reproducibility for MP detection. Moreover, the proposed biosensor showed better electrode stability when stored at 4 °C. This new electrochemical biosensor is also exhibited high selectivity and sensitivity for MP, which made it possible to test MP in real strawberry and apple juices. Furthermore, the BSA/AChE-Glu-s-SWCNTs/GCE offered a favourable electron transfer between the acetylthiocholine chloride (ATCl) and electrode interface than BSA/AChE-s-SWCNTs/GCE, s-SWCNTs/GCE and bare GCE.


Assuntos
Acetilcolinesterase/química , Inseticidas/análise , Metil Paration/análise , Nanocompostos/química , Nanotubos de Carbono/química , Soroalbumina Bovina/química , Animais , Técnicas Biossensoriais/métodos , Carbono , Bovinos , Reagentes para Ligações Cruzadas/química , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Electrophorus , Enzimas Imobilizadas/química , Contaminação de Alimentos/análise , Fragaria/química , Glutaral/química , Inseticidas/química , Limite de Detecção , Malus/química , Metil Paration/química , Reprodutibilidade dos Testes
11.
Food Chem ; 295: 189-197, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174749

RESUMO

The presented study examined the influence of hydroxypropylmethylcellulose (HPMC), sugar beet fibre (SBF) and apple fibre (AF) incorporation coupled with adequate water levels on gluten-free (GF) batter rheology, bread quality and sensory characteristics. A Box-Behnken experimental design with independent variables: HPMC quantity (2-4 g/100 g), SBF and AF quantity (3-7 g/100 g) and water quantity (180-230 g/100 g depending on the fibre type) based on a maize flour/starch mixture was applied. GF breads with 4 g/100 g HPMC coupled with 3 g/100 g SBF and 7 g/100 g AF reached the highest specific volumes (2.44 cm3/g and 3.97 cm3/g) accompanied with the lowest crumb hardness (2.29 and 2.10 N, respectively). Appealing crust and crumb colour and good sensory characteristics were achieved in GF breads with 4 g/100 g HPMC and 3, 5 and 7 g/100 g SBF or AF. The corresponding GF breads showed enhanced fibre content (4.56-6.07 g/100 g).


Assuntos
Beta vulgaris/química , Pão , Malus/química , Adulto , Dieta Livre de Glúten , Fibras na Dieta , Feminino , Farinha , Qualidade dos Alimentos , Dureza , Humanos , Derivados da Hipromelose , Masculino , Pessoa de Meia-Idade , Reologia , Amido , Paladar , Zea mays/química
12.
Food Chem ; 295: 254-258, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174756

RESUMO

In this work, we report a simple and rapid surface-enhanced Raman scattering (SERS) method for the screening of pesticide residues on fruit peels using a portable Raman spectrometer. Adhesive tapes were used as the sampling media; the effectiveness of different tape brands was examined. Collection efficiencies were found to be 60.2 ±â€¯7.6%, 54.3 ±â€¯5.0%, and 52.3 ±â€¯9.0% on glass, aluminum foil, and fruit peels, respectively. SERS was achieved by applying silver nanoparticles (Ag NPs) to the surface of the tape after analyte collection. Preparation of the Ag NPs was optimized for pesticide detection. The limit of detection of triazophos on apple peels was 25 ng/cm2 with the portable Raman spectrometer. Considering the least favorable conditions, the calculated detection limit was 0.0225 mg/kg, which is an order of magnitude less than the maximum residue limit (MRL, 0.2 mg/kg) in China. The method is sufficiently sensitive for use in field analysis.


Assuntos
Contaminação de Alimentos/análise , Frutas/química , Resíduos de Praguicidas/análise , Análise Espectral Raman/métodos , Adesivos/química , China , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Limite de Detecção , Malus/química , Nanopartículas Metálicas/química , Organotiofosfatos/análise , Prata/química , Análise Espectral Raman/instrumentação , Triazóis/análise
13.
J Sci Food Agric ; 99(13): 5662-5670, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31150567

RESUMO

BACKGROUND: The fruit of two apple cultivars - 'Braeburn', which is susceptible to inoculation with Botrytis cinerea, and the less susceptible cv. 'Golden Delicious' - were investigated with respect to their response to inoculation with B. cinerea. Successful infection by B. cinerea leads to an oxidative burst and perturbation of plant redox homeostasis. To investigate the interaction between apple fruit and B. cinerea, antioxidant metabolism in fruit samples from sun-exposed and shaded sides of different tissue types was measured over time. RESULTS: The sun-exposed tissue of 'Braeburn' had higher initial levels of total vitamin C in the peel and phenolic compounds in the flesh than 'Golden Delicious', despite its greater susceptibility to gray mold. A substantial antioxidant response was recorded in diseased 'Braeburn' fruit 14 days after inoculation, which involved an elevated superoxide dismutase activity and ascorbate peroxidase activity, a progressive oxidation of total vitamin C, and a decrease in peroxidase activity and phenolic content. Disease development was slower on the sun-exposed sides than on the shaded sides. CONCLUSION: The two cultivars appeared to utilize different strategies to defend themselves against B. cinerea. 'Golden Delicious' almost entirely escaped infection. Preharvest exposure of apple fruit to high light / temperature stress appears to prepare them to better resist subsequent postharvest attack and disease. © 2019 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Antioxidantes/metabolismo , Botrytis/fisiologia , Frutas/microbiologia , Malus/microbiologia , Doenças das Plantas/microbiologia , Ácido Ascórbico/análise , Ácido Ascórbico/metabolismo , Cor , Frutas/química , Frutas/metabolismo , Malus/química , Malus/metabolismo , Fenóis/química , Fenóis/metabolismo , Explosão Respiratória
14.
J Sci Food Agric ; 99(14): 6182-6190, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31250438

RESUMO

BACKGROUND: Apples from different regions of China show different qualities and internal characteristics, and appeal to different customers. However, these aspects have not been studied in depth. We characterized the profiles of 14 elements in 317 apple samples collected from five regions of China. Principal component analysis (PCA), linear discriminant analysis (LDA), and back-propagation artificial neural networks analysis (BP-ANN) were used to build models for apple authentication. RESULTS: Fourteen elements were successfully identified in apple samples by performing graphite furnace atomic absorption spectrometry (GFAAS) and inductively coupled plasma atomic emission spectroscopy (ICP-AES) analyses. Comparative analysis showed significantly different element profiles in samples from different regions. The first five principal components obtained by PCA accounted for 71.8% of the total variance. The LDA obtained 70.0% classification rates. The BP-ANN obtained 82.7% classification rates. CONCLUSION: This study indicated the possibility that apples could be authenticated based on differences in their element profiles, and provided a basis for further geographical origin studies. © 2019 Society of Chemical Industry.


Assuntos
Malus/química , Oligoelementos/química , China , Análise Discriminante , Frutas/química , Frutas/classificação , Malus/classificação , Análise de Componente Principal , Espectrofotometria Atômica
15.
J Sci Food Agric ; 99(14): 6248-6257, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31250453

RESUMO

BACKGROUND: Osmotic pretreatment is an effective processing unit for improving the textural quality of dried fruit and vegetable snacks, whereas nutrition loss and high calorie after impregnation is still a noteworthy shortcoming of sugar-immersed products. Therefore, the use of apple juice concentrate as a clean label solution to improve the qualities of instant controlled pressure drop (DIC)-dried carrot chips was investigated. RESULTS: Apple juice concentrate impregnation substantially enhanced the physical properties of the carrot chips, including hardness (38.28 N), crispness (2.01 mm), porosity (66.72%) and homogeneous microstructure, comparable to chips obtained using sucrose and maltiltol based osmotic solutions. Additionally, compared to the sucrose and maltiltol impregnated chips, a higher retention of carotenoids (302.81 µg g-1 , dry basis), a higher multiplicity of phenolic compounds, stronger antioxidant activities and a superior sensory score were observed in the chips pretreated with apple juice concentrate. CONCLUSION: Apple juice concentrate could be used as a clean label osmotic solution to enhance the organoleptic attributes and fortify the nutritional properties of DIC-dried carrot snacks. © 2019 Society of Chemical Industry.


Assuntos
Daucus carota/química , Aditivos Alimentares/análise , Sucos de Frutas e Vegetais/análise , Malus/química , Carotenoides/análise , Manipulação de Alimentos/métodos , Humanos , Valor Nutritivo , Osmose , Fenóis/análise , Pressão , Lanches , Paladar
16.
Food Chem ; 296: 142-149, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31202298

RESUMO

Little data are available on the impact of pomace pre-treatment, notably drying, on the nature and yield of polyphenols. Pomace from two apple varieties ('Avrolles' and 'Kermerrien'), pressed with and without oxidation, were air-dried to different degrees. Drying led to the loss of native molecules, notably 5-O-caffeoylquinic acid and flavan-3-ols. Total polyphenol yields, after sequential pressurized liquid extraction (water 10 MPa, 70 °C, then ethanol 48%, 10 MPa, 70 °C), varied between 5 and 15 g/kg dry weight but showed no marked trend with drying. Extracts from dried pomace contained few native polyphenols. Water extracts from 'Kermerrien' contained flavonols, flavanols and phloridzin and those from 'Avrolles' contained phloridzin. Water:ethanol extracts were rich in procyanidins, especially from 'Avrolles', where they represented >80% of analysable polyphenols. Presence of polyphenol molecules with modified structures in the extracts of dried pomaces might lead to different biological properties than those with native molecules.


Assuntos
Dessecação/métodos , Malus/química , Extratos Vegetais/química , Polifenóis/química , Flavanonas/química , Malus/metabolismo , Polifenóis/isolamento & purificação , Polissacarídeos/química , Proantocianidinas/química
17.
J Agric Food Chem ; 67(26): 7435-7447, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31244205

RESUMO

Pectic oligosaccharides (POS) from citrus and apple pectin hydrolysis using ViscozymeL and Glucanex200G have been obtained. According to the results, maximum POS formation was achieved from citrus pectin after 30 min of hydrolysis with ViscozymeL, with a yield of 652 mg g-1 and average molecular mass ( Mw) of 0.8-2.5 kDa, while with Glucanex200G, the yield was 518 mg g-1 and Mw was 0.8-7.1 kDa. Digalacturonic and trigalacturonic acids were identified among other low Mw compounds as di- and tri-POS. In addition, differences in GC-MS spectra of all oligosaccharides found in the hydrolysates were studied by employing random forests and other algorithms to identify structural differences between the obtained POS, and high prediction rates were shown for new samples. Chemical structures were proposed for some influential m/ z ions, and 12 association rules that explain differences according to pectin and enzyme origin were built. This information could be used to establish structure-function relationships of POS.


Assuntos
Citrus/química , Malus/química , Complexos Multienzimáticos/química , Oligossacarídeos/química , Pectinas/química , Extratos Vegetais/química , Biocatálise , Cromatografia Gasosa-Espectrometria de Massas , Hidrólise , Peso Molecular
18.
Food Chem Toxicol ; 131: 110563, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31199992

RESUMO

Apple pomace (AP) utilised for analysis of triterpenic acids (TTAs) using HPLC-MS/MS. The methanol, ethanol and ethyl acetate extracts showed high phenolic content with significant antioxidant activity compared to chloroform and n-hexane. AP TTAs; ursolic acid, betulinic acid and maslinic acid showed potent antioxidant and enzyme inhibitory effects. The IC50 values were 13.2-30.8 µg/mL (tyrosinase), 19.6-42.5 µg/mL (xanthine oxidase) and 16.6-38.6 µg/mL (urease) for AP extracts and 8.4-25.8 µg/mL (tyrosinase), 12.6-30.2 µg/mL (xanthine oxidase) and 10.1-28.6 µg/mL (urease) for TTAs, compared to the positive controls; kojic acid (10.4 ±â€¯0.06 µg/mL), allopurinol (9.6 ±â€¯0.04 µg/mL) and thiourea (8.9 ±â€¯0.02 µg/mL) towards respective enzymes. UA showed a competitive type of inhibition for tyrosinase, while BA showed a noncompetitive type of inhibition towards xanthine oxidase. In addition, the AP extracts and TTAs exerted significant cytotoxic effects towards the proliferation of cancer cell lines. AP methanol extract (IC50 of 38.5 ±â€¯4.1, 47.1 ±â€¯3.5, 70.6 ±â€¯2.3, and 50.5 ±â€¯3.9 µg/mL) and ursolic acid (IC50 of 6.5 ±â€¯0.7, 15.5 ±â€¯1.4, 20.8 ±â€¯1.3, and 5.6 ±â€¯0.8 µg/mL) showed prominent anticancer activity on Hela, Skov-3, Caski, and NCL cancer cell lines, respectively. Thus, this study shows that the AP & TTAs could be utilized for functional food development and as a potent antioxidant, anticancer, skin whitening, and anti-urolithic agents.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Depuradores de Radicais Livres/farmacologia , Frutas/química , Malus/química , Triterpenos/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Cães , Ensaios Enzimáticos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Depuradores de Radicais Livres/química , Depuradores de Radicais Livres/isolamento & purificação , Humanos , Células Madin Darby de Rim Canino , Monofenol Mono-Oxigenase/antagonistas & inibidores , Extratos Vegetais/análise , Extratos Vegetais/química , Extração em Fase Sólida , Triterpenos/química , Triterpenos/isolamento & purificação , Urease/antagonistas & inibidores , Xantina Oxidase/antagonistas & inibidores
19.
J Agric Food Chem ; 67(28): 8045-8052, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31241326

RESUMO

n-Octadecylamine was adopted as a cleanup agent to develop a novel solidification of a switchable solvent-based QuEChERS method. At higher temperatures (such as 55 °C), n-octadecylamine can melt into a liquid, allowing effective extraction of matrix interferences in acetonitrile solution (i.e., in dispersive liquid-liquid microextraction). At lower temperatures, n-octadecylamine carrying matrix interferences can rapidly solidify and easily separate from the acetonitrile solution. The results demonstrated that n-octadecylamine possessed a better ability to remove matrix interferences and reduce matrix effects than those of traditional solid-phase dispersive extraction cleanup agents of primary secondary amine and octadecyl bonded silica gel. By coupling it with gas chromatography-mass spectrometry, the proposed method was applied to the detection of 16 pesticides in cucumber. The recoveries were from 80.9 to 112.6% with relative standard deviations less than 12.9%. Satisfactory results were also obtained for the detection of 16 pesticides in pear, orange, apple, pepper, lettuce, and tomato.


Assuntos
Frutas/química , Microextração em Fase Líquida/métodos , Resíduos de Praguicidas/química , Resíduos de Praguicidas/isolamento & purificação , Verduras/química , Acetonitrilos/química , Aminas/química , Citrus sinensis/química , Cucumis sativus/química , Cromatografia Gasosa-Espectrometria de Massas , Alface/química , Microextração em Fase Líquida/instrumentação , Lycopersicon esculentum/química , Malus/química , Solventes/química
20.
J Sci Food Agric ; 99(13): 5792-5798, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31162672

RESUMO

BACKGROUND: Recently, a producer of fermented ciders observed 'vinyl' off-odors formed during fermentation of pear juice previously depectinized at ≥ 49 °C but not if depectinized at lower temperatures. The objective of this study was to investigate the source of this spoilage and evaluate factors that affect formation. RESULTS: Analysis of untainted and tainted samples obtained from the producer determined the causative agent to be indole, a compound sometimes produced by yeast (Saccharomyces cerevisiae) during fermentation. To mimic commercial depectinization conditions, pectinases were added to pear juices held at 35 °C for 45 min (Treatment A), 49 °C for 45 min (Treatment B), or 49 °C for 90 min (Treatment C). Juice processing conditions did not affect yeast growth nor progress of alcoholic fermentation. Although neither yeast strain (DV10 or MERIT) synthesized indole during fermentation of Treatment A juices, the compound was produced by MERIT in Treatments B (27.05 µg L-1 ) and C (469.9 µg L-1 ). Supplementation of Treatment C juice with pyridoxine (vitamin B6 ) prior to fermentation resulted in no detectable indole formed. However, juices from Treatments A, B, or C contained similar concentrations of pyridoxine and non-detectable amounts of tryptophan, a potential precursor to indole. Furthermore, indole was not detected during fermentations of a synthetic pear juice medium without pyridoxine. CONCLUSION: Supplementation of cider musts with pyridoxine prior to fermentation and choice of yeast strain can lower the risk of formation of off-odors caused by indole. However, other unidentified factors are present which affect its formation in perry. © 2019 Society of Chemical Industry.


Assuntos
Bebidas Alcoólicas/análise , Etanol/metabolismo , Manipulação de Alimentos/métodos , Indóis/metabolismo , Pectinas/metabolismo , Pyrus/química , Saccharomyces cerevisiae/metabolismo , Bebidas Alcoólicas/microbiologia , Etanol/análise , Fermentação , Sucos de Frutas e Vegetais/análise , Sucos de Frutas e Vegetais/microbiologia , Indóis/análise , Malus/química , Malus/microbiologia , Odorantes/análise , Poligalacturonase/química , Pyrus/microbiologia
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